Merge pull request #1609 from github/v1.7.2

v1.7.2

.gitattributes

@@ -18,4 +18,8 @@ yarn.lock                    merge=binary
 # https://mirrors.edge.kernel.org/pub/software/scm/git/docs/gitattributes.html
 # suggests that this might interleave lines arbitrarily, but empirically
 # it keeps added chunks contiguous
-CHANGELOG.md                merge=union
+CHANGELOG.md                merge=union
+
+# Mark some JSON files containing test data as generated so they are not included
+# as part of diffs or language statistics.
+extensions/ql-vscode/src/stories/remote-queries/data/*.json     linguist-generated

.github/ISSUE_TEMPLATE/bug_report.md

@@ -10,7 +10,12 @@ assignees: ''
 **Describe the bug**
 A clear and concise description of what the bug is.
 
-**To Reproduce**
+**Version**
+The CodeQL and VS Code version in which the bug occurs.
+<!-- To copy version information for the CodeQL extension, click "CodeQL CLI vX.X.X" in the status bar at the bottom of the screen. 
+To copy detailed version information for VS Code itself, see https://code.visualstudio.com/docs/supporting/FAQ#_how-do-i-find-the-version. -->
+
+**To reproduce**
 Steps to reproduce the behavior.
 
 **Expected behavior**

.github/ISSUE_TEMPLATE/new-extension-release.md

@@ -1,18 +0,0 @@
----
-name: New extension release
-about: Create an issue with a checklist for the release steps (write access required
-  for the steps)
-title: Release Checklist for version xx.xx.xx
-labels: ''
-assignees: ''
-
----
-
-- [ ] Update this issue title to refer to the version of the release
-- [ ] Trigger a release build on Actions by adding a new tag on branch `main` of the format `vxx.xx.xx`
-- [ ] Monitor the status of the release build in the `Release` workflow in the Actions tab.
-- [ ] Download the VSIX from the draft GitHub release that is created when the release build finishes.
-- [ ] Log into the [Visual Studio Marketplace](https://marketplace.visualstudio.com/manage/publishers/github).
-- [ ] Click the `...` menu in the CodeQL row and click **Update**.
-- [ ] Drag the `.vsix` file you downloaded from the GitHub release into the Marketplace and click **Upload**.
-- [ ] Publish the draft GitHub release and confirm the new release is marked as the latest release at https://github.com/github/vscode-codeql/releases.

.github/dependabot.yml

@@ -0,0 +1,22 @@
+version: 2
+updates:
+  - package-ecosystem: "npm"
+    directory: "extensions/ql-vscode"
+    schedule:
+      interval: "weekly"
+      day: "thursday" # Thursday is arbitrary
+    labels:
+      - "Update dependencies"
+    ignore:
+      - dependency-name: "*"
+        update-types: ["version-update:semver-minor", "version-update:semver-patch"]
+  - package-ecosystem: "github-actions"
+    directory: ".github"
+    schedule:
+      interval: "weekly"
+      day: "thursday" # Thursday is arbitrary
+    labels:
+      - "Update dependencies"
+    ignore:
+      - dependency-name: "*"
+        update-types: ["version-update:semver-minor", "version-update:semver-patch"]

.github/pull_request_template.md

@@ -9,4 +9,4 @@ Replace this with a description of the changes your pull request makes.
 
 - [ ] [CHANGELOG.md](https://github.com/github/vscode-codeql/blob/main/extensions/ql-vscode/CHANGELOG.md) has been updated to incorporate all user visible changes made by this pull request.
 - [ ] Issues have been created for any UI or other user-facing changes made by this pull request.
-- [ ] `@github/docs-content-dsp` has been cc'd in all issues for UI or other user-facing changes made by this pull request.
+- [ ] _[Maintainers only]_ If this pull request makes user-facing changes that require documentation changes, open a corresponding docs pull request in the [github/codeql](https://github.com/github/codeql/tree/main/docs/codeql/codeql-for-visual-studio-code) repo and add the `ready-for-doc-review` label there.

.github/workflows/codeql.yml

@@ -2,24 +2,31 @@ name: "Code Scanning - CodeQL"
 
 on:
   push:
+    branches: [main]
   pull_request:
+    branches: [main]
   schedule:
-    - cron: '0 0 * * 0'
+    - cron: '21 17 * * 0'
 
 jobs:
   codeql:
-    strategy:
-      fail-fast: false
     runs-on: ubuntu-latest
+
+    permissions:
+      contents: read
+      security-events: write
+      pull-requests: read
+
     steps:
       - name: Checkout repository
         uses: actions/checkout@v2
 
       - name: Initialize CodeQL
-        uses: github/codeql-action/init@v1
+        uses: github/codeql-action/init@main
         with:
             languages: javascript
             config-file: ./.github/codeql/codeql-config.yml
+            tools: latest
 
       - name: Perform CodeQL Analysis
-        uses: github/codeql-action/analyze@v1
+        uses: github/codeql-action/analyze@main

.github/workflows/dependency-review.yml

@@ -0,0 +1,16 @@
+name: 'Dependency Review'
+on:
+  - pull_request
+  - workflow_dispatch
+
+permissions:
+  contents: read
+
+jobs:
+  dependency-review:
+    runs-on: ubuntu-latest
+    steps:
+      - name: 'Checkout Repository'
+        uses: actions/checkout@v3
+      - name: 'Dependency Review'
+        uses: actions/dependency-review-action@v1

.github/workflows/main.yml

@@ -1,6 +1,8 @@
 name: Build Extension
 on:
+  workflow_dispatch:
   pull_request:
+    types: [opened, synchronize, reopened, ready_for_review]
   push:
     branches:
       - main
@@ -20,17 +22,19 @@ jobs:
 
       - uses: actions/setup-node@v1
         with:
-          node-version: '10.18.1'
+          node-version: '16.14.2'
 
       - name: Install dependencies
+        working-directory: extensions/ql-vscode
         run: |
-          cd extensions/ql-vscode
           npm install
         shell: bash
 
       - name: Build
+        working-directory: extensions/ql-vscode
+        env:
+          APP_INSIGHTS_KEY: '${{ secrets.APP_INSIGHTS_KEY }}'
         run: |
-          cd extensions/ql-vscode
           npm run build
         shell: bash
 
@@ -47,9 +51,26 @@ jobs:
           name: vscode-codeql-extension
           path: artifacts
 
+  find-nightly:
+    name: Find Nightly Release
+    runs-on: ubuntu-latest
+    outputs:
+      url: ${{ steps.get-url.outputs.nightly-url }}
+    steps:
+      - name: Get Nightly Release URL
+        id: get-url
+        env:
+          GITHUB_TOKEN: '${{ secrets.GITHUB_TOKEN }}'
+        shell: bash
+        # This workflow step gets an unstable testing version of the CodeQL CLI. It should not be used outside of these tests.
+        run: |
+          LATEST=`gh api repos/dsp-testing/codeql-cli-nightlies/releases --jq '.[].tag_name' --method GET --raw-field 'per_page=1'`
+          echo "::set-output name=nightly-url::https://github.com/dsp-testing/codeql-cli-nightlies/releases/download/$LATEST"
+
   test:
     name: Test
     runs-on: ${{ matrix.os }}
+    needs: [find-nightly]
     strategy:
       matrix:
         os: [ubuntu-latest, windows-latest]
@@ -61,57 +82,116 @@ jobs:
 
       - uses: actions/setup-node@v1
         with:
-          node-version: '10.18.1'
+          node-version: '16.14.0'
 
-      # We have to build the dependencies in `lib` before running any tests.
       - name: Install dependencies
+        working-directory: extensions/ql-vscode
         run: |
-          cd extensions/ql-vscode
           npm install
         shell: bash
 
       - name: Build
+        working-directory: extensions/ql-vscode
+        env:
+          APP_INSIGHTS_KEY: '${{ secrets.APP_INSIGHTS_KEY }}'
         run: |
-          cd extensions/ql-vscode
           npm run build
         shell: bash
 
       - name: Lint
+        working-directory: extensions/ql-vscode
         run: |
-          cd extensions/ql-vscode
           npm run lint
 
-      - name: Install CodeQL
-        run: |
-          mkdir codeql-home
-          curl -L --silent https://github.com/github/codeql-cli-binaries/releases/latest/download/codeql.zip -o codeql-home/codeql.zip
-          unzip -q -o codeql-home/codeql.zip -d codeql-home
-          unzip -q -o codeql-home/codeql.zip codeql/codeql.exe -d codeql-home
-          rm codeql-home/codeql.zip
-        shell: bash
-
       - name: Run unit tests (Linux)
+        working-directory: extensions/ql-vscode
         if: matrix.os == 'ubuntu-latest'
         run: |
-          cd extensions/ql-vscode
-          CODEQL_PATH=$GITHUB_WORKSPACE/codeql-home/codeql/codeql npm run test
+          npm run test
 
       - name: Run unit tests (Windows)
         if: matrix.os == 'windows-latest'
+        working-directory: extensions/ql-vscode
         run: |
-          cd extensions/ql-vscode
-          $env:CODEQL_PATH=$(Join-Path $env:GITHUB_WORKSPACE -ChildPath 'codeql-home/codeql/codeql.exe')
           npm run test
 
       - name: Run integration tests (Linux)
         if: matrix.os == 'ubuntu-latest'
+        working-directory: extensions/ql-vscode
+        env:
+          VSCODE_CODEQL_GITHUB_TOKEN: '${{ secrets.GITHUB_TOKEN }}'
         run: |
-          cd extensions/ql-vscode
           sudo apt-get install xvfb
           /usr/bin/xvfb-run npm run integration
 
       - name: Run integration tests (Windows)
         if: matrix.os == 'windows-latest'
+        working-directory: extensions/ql-vscode
+        env:
+          VSCODE_CODEQL_GITHUB_TOKEN: '${{ secrets.GITHUB_TOKEN }}'
         run: |
-          cd extensions/ql-vscode
           npm run integration
+
+  cli-test:
+    name: CLI Test
+    runs-on: ${{ matrix.os }}
+    needs: [find-nightly]
+    strategy:
+      matrix:
+        os: [ubuntu-latest, windows-latest]
+        version: ['v2.6.3', 'v2.7.6', 'v2.8.5', 'v2.9.4', 'v2.10.5', 'v2.11.1', 'nightly']
+    env:
+      CLI_VERSION: ${{ matrix.version }}
+      NIGHTLY_URL: ${{ needs.find-nightly.outputs.url }}
+      TEST_CODEQL_PATH: '${{ github.workspace }}/codeql'
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+
+      - uses: actions/setup-node@v1
+        with:
+          node-version: '16.14.0'
+
+      - name: Install dependencies
+        working-directory: extensions/ql-vscode
+        run: |
+          npm install
+        shell: bash
+
+      - name: Build
+        working-directory: extensions/ql-vscode
+        run: |
+          npm run build
+        shell: bash
+
+      - name: Decide on ref of CodeQL repo
+        id: choose-ref
+        shell: bash
+        run: |
+          if [[ "${{ matrix.version }}" == "nightly" ]]
+          then
+            REF="codeql-cli/latest"
+          else
+            REF="codeql-cli/${{ matrix.version }}"
+          fi
+          echo "::set-output name=ref::$REF"
+
+      - name: Checkout QL
+        uses: actions/checkout@v2
+        with:
+          repository: github/codeql
+          ref: ${{ steps.choose-ref.outputs.ref }}
+          path: codeql
+
+      - name: Run CLI tests (Linux)
+        working-directory: extensions/ql-vscode
+        if: matrix.os == 'ubuntu-latest'
+        run: |
+          /usr/bin/xvfb-run npm run cli-integration
+
+      - name: Run CLI tests (Windows)
+        working-directory: extensions/ql-vscode
+        if: matrix.os == 'windows-latest'
+        run: |
+          npm run cli-integration

.github/workflows/release.yml

@@ -6,10 +6,6 @@
 
 name: Release
 on:
-  pull_request:
-    paths:
-      - '**/workflows/release.yml'
-
   workflow_dispatch:
 
   push:
@@ -20,23 +16,25 @@ jobs:
   build:
     name: Release
     runs-on: ubuntu-latest
-    # TODO Share steps with the main workflow.
     steps:
       - name: Checkout
         uses: actions/checkout@v2
 
       - uses: actions/setup-node@v1
         with:
-          node-version: '10.18.1'
+          node-version: '16.14.2'
 
       - name: Install dependencies
         run: |
           cd extensions/ql-vscode
-          npm install
+          npm ci
         shell: bash
 
       - name: Build
+        env:
+          APP_INSIGHTS_KEY: '${{ secrets.APP_INSIGHTS_KEY }}'
         run: |
+          echo "APP INSIGHTS KEY LENGTH: ${#APP_INSIGHTS_KEY}"
           cd extensions/ql-vscode
           npm run build -- --release
         shell: bash
@@ -55,9 +53,6 @@ jobs:
           REF_NAME="$(echo ${{ github.ref }} | sed -e 's:^refs/tags/::' | sed -e 's:/:-:g')"
           echo "::set-output name=ref_name::$REF_NAME"
 
-      # Uploading artifacts is not necessary to create a release.
-      # This is just in case the release itself fails and we want to access the built artifacts from Actions.
-      # TODO Remove if not useful.
       - name: Upload artifacts
         uses: actions/upload-artifact@v2
         with:
@@ -93,6 +88,10 @@ jobs:
           asset_name: ${{ format('vscode-codeql-{0}.vsix', steps.prepare-artifacts.outputs.ref_name) }}
           asset_content_type: application/zip
 
+      ###
+      # Do Post release work: version bump and changelog PR
+      # Only do this if we are running from a PR (ie- this is part of the release process)
+
       # The checkout action does not fetch the main branch.
       # Fetch the main branch so that we can base the version bump PR against main.
       - name: Fetch main branch
@@ -126,3 +125,41 @@ jobs:
           body: This PR was automatically generated by the GitHub Actions release workflow in this repository.
           branch: ${{ format('version/bump-to-{0}', steps.bump-patch-version.outputs.next_version) }}
           base: main
+          draft: true
+
+  vscode-publish:
+    name: Publish to VS Code Marketplace
+    needs: build
+    environment: publish-vscode-marketplace
+    runs-on: ubuntu-latest
+    env:
+      VSCE_TOKEN: ${{ secrets.VSCE_TOKEN }}
+    steps:
+      - name: Download artifact
+        uses: actions/download-artifact@v2
+        with:
+          name: vscode-codeql-extension
+
+      - name: Publish to Registry
+        run: |
+          npx vsce publish -p $VSCE_TOKEN --packagePath *.vsix || \
+            echo "Failed to publish to VS Code Marketplace. \
+                  If this was an authentication problem, please make sure the \
+                  auth token hasn't expired."
+
+  open-vsx-publish:
+    name: Publish to Open VSX Registry
+    needs: build
+    environment: publish-open-vsx
+    runs-on: ubuntu-latest
+    env:
+      OPEN_VSX_TOKEN: ${{ secrets.OPEN_VSX_TOKEN }}
+    steps:
+      - name: Download artifact
+        uses: actions/download-artifact@v2
+        with:
+          name: vscode-codeql-extension
+
+      - name: Publish to Registry
+        run: |
+          npx ovsx publish -p $OPEN_VSX_TOKEN *.vsix

.gitignore

@@ -4,6 +4,7 @@
 # Generated files
 /dist/
 out/
+build/
 server/
 node_modules/
 gen/

.vscode/extensions.json

@@ -1,9 +1,9 @@
 {
-  // See http://go.microsoft.com/fwlink/?LinkId=827846 to learn about workspace recommendations.
+  // See https://go.microsoft.com/fwlink/?LinkId=827846 to learn about workspace recommendations.
   // Extension identifier format: ${publisher}.${name}. Example: vscode.csharp
   // List of extensions which should be recommended for users of this workspace.
   "recommendations": [
-    "eamodio.tsl-problem-matcher",
+    "amodio.tsl-problem-matcher",
     "dbaeumer.vscode-eslint",
     "eternalphane.tsfmt-vscode"
   ],

.vscode/launch.json

@@ -8,9 +8,10 @@
       "request": "launch",
       "runtimeExecutable": "${execPath}",
       "args": [
-        "--extensionDevelopmentPath=${workspaceRoot}/extensions/ql-vscode"
+        "--extensionDevelopmentPath=${workspaceRoot}/extensions/ql-vscode",
+        // Add a reference to a workspace to open. Eg-
+        // "${workspaceRoot}/../vscode-codeql-starter/vscode-codeql-starter.code-workspace"
       ],
-      "stopOnEntry": false,
       "sourceMaps": true,
       "outFiles": [
         "${workspaceRoot}/extensions/ql-vscode/out/**/*.js",
@@ -19,6 +20,9 @@
         // change to 'true' debug the IDE or Query servers
         "IDE_SERVER_JAVA_DEBUG": "false",
         "QUERY_SERVER_JAVA_DEBUG": "false",
+        "CLI_SERVER_JAVA_DEBUG": "false",
+        // Uncomment to set the JAVA_HOME for the codeql instance to use
+        // "CODEQL_JAVA_HOME": "/Library/Java/JavaVirtualMachines/jdk-12.0.1.jdk/Contents/Home"
       }
     },
     {
@@ -31,6 +35,9 @@
       "runtimeArgs": [
         "--inspect=9229"
       ],
+      "env": {
+        "LANG": "en-US"
+      },
       "args": [
         "--exit",
         "-u",
@@ -39,9 +46,22 @@
         "--diff",
         "-r",
         "ts-node/register",
+        "-r",
+        "test/mocha.setup.js",
         "test/pure-tests/**/*.ts"
       ],
-      "port": 9229,
+      "stopOnEntry": false,
+      "sourceMaps": true,
+      "console": "integratedTerminal",
+      "internalConsoleOptions": "neverOpen"
+    },
+    {
+      "name": "Launch Unit Tests - React (vscode-codeql)",
+      "type": "node",
+      "request": "launch",
+      "program": "${workspaceFolder}/extensions/ql-vscode/node_modules/jest/bin/jest.js",
+      "showAsyncStacks": true,
+      "cwd": "${workspaceFolder}/extensions/ql-vscode",
       "stopOnEntry": false,
       "sourceMaps": true,
       "console": "integratedTerminal",
@@ -54,9 +74,11 @@
       "runtimeExecutable": "${execPath}",
       "args": [
         "--extensionDevelopmentPath=${workspaceRoot}/extensions/ql-vscode",
-        "--extensionTestsPath=${workspaceRoot}/extensions/ql-vscode/out/vscode-tests/no-workspace/index"
+        "--extensionTestsPath=${workspaceRoot}/extensions/ql-vscode/out/vscode-tests/no-workspace/index",
+        "--disable-workspace-trust",
+        "--disable-extensions",
+        "--disable-gpu"
       ],
-      "stopOnEntry": false,
       "sourceMaps": true,
       "outFiles": [
         "${workspaceRoot}/extensions/ql-vscode/out/**/*.js",
@@ -70,13 +92,63 @@
       "args": [
         "--extensionDevelopmentPath=${workspaceRoot}/extensions/ql-vscode",
         "--extensionTestsPath=${workspaceRoot}/extensions/ql-vscode/out/vscode-tests/minimal-workspace/index",
+        "--disable-workspace-trust",
+        "--disable-extensions",
+        "--disable-gpu",
         "${workspaceRoot}/extensions/ql-vscode/test/data"
       ],
-      "stopOnEntry": false,
       "sourceMaps": true,
       "outFiles": [
         "${workspaceRoot}/extensions/ql-vscode/out/**/*.js",
       ],
+    },
+    {
+      "name": "Launch Integration Tests - With CLI",
+      "type": "extensionHost",
+      "request": "launch",
+      "runtimeExecutable": "${execPath}",
+      "args": [
+        "--extensionDevelopmentPath=${workspaceRoot}/extensions/ql-vscode",
+        "--extensionTestsPath=${workspaceRoot}/extensions/ql-vscode/out/vscode-tests/cli-integration/index",
+        "--disable-workspace-trust",
+        "--disable-gpu",
+        "--disable-extension",
+        "eamodio.gitlens",
+        "--disable-extension",
+        "github.codespaces",
+        "--disable-extension",
+        "github.copilot",
+        "${workspaceRoot}/extensions/ql-vscode/src/vscode-tests/cli-integration/data",
+        // Uncomment the last line and modify the path to a checked out 
+        // instance of the codeql repository so the libraries are
+        // available in the workspace for the tests.
+        // "${workspaceRoot}/../codeql"
+      ],
+      "env": {
+        // Optionally, set the version to use for the integration tests.
+        // Use "nightly" to use the latest nightly build.
+        // "CLI_VERSION": "2.7.0",
+
+        // If CLI_VERSION is set to nightly, set this to the url of the nightly build.
+        // "NIGHTLY_URL": "some url to grab the nightly build",
+
+        // Optionally, add a path to the codeql executable to be used during these tests.
+        // If not specified, one will be downloaded automatically.
+        // This option overrides the CLI_VERSION option.
+        // "CLI_PATH": "${workspaceRoot}/../semmle-code/target/intree/codeql/codeql",
+      },
+      "sourceMaps": true,
+      "outFiles": [
+        "${workspaceRoot}/extensions/ql-vscode/out/**/*.js",
+      ],
+    },
+    {
+      "name": "Launch Storybook",
+      "type": "node",
+      "request": "launch",
+      "cwd": "${workspaceFolder}/extensions/ql-vscode",
+      "runtimeExecutable": "npm",
+      "runtimeArgs": ["run-script", "storybook"]
     }
   ]
 }

.vscode/settings.json

@@ -22,19 +22,19 @@
     "common/temp": true,
     "**/.vscode-test": true
   },
-  "typescript.tsdk": "./common/temp/node_modules/typescript/lib", // we want to use the TS server from our node_modules folder to control its version
+  "typescript.tsdk": "./extensions/ql-vscode/node_modules/typescript/lib", // we want to use the TS server from our node_modules folder to control its version
+  "typescript.enablePromptUseWorkspaceTsdk": true,
   "eslint.validate": [
     "javascript",
     "javascriptreact",
     "typescript",
     "typescriptreact"
   ],
-  "eslint.options": {
-    // This is necessary so that eslint can properly resolve its plugins
-    "resolvePluginsRelativeTo": "./extensions/ql-vscode"
-  },
+  // This is necessary to ensure that ESLint can find the correct configuration files and plugins.
+  "eslint.workingDirectories": ["./extensions/ql-vscode"],
   "editor.formatOnSave": false,
   "typescript.preferences.quoteStyle": "single",
   "javascript.preferences.quoteStyle": "single",
-  "editor.wordWrapColumn": 100
+  "editor.wordWrapColumn": 100,
+  "jest.rootPath": "./extensions/ql-vscode"
 }

CODEOWNERS

@@ -0,0 +1,3 @@
+**/* @github/codeql-vscode-reviewers
+**/remote-queries/ @github/code-scanning-secexp-reviewers
+**/variant-analysis/ @github/code-scanning-secexp-reviewers

CONTRIBUTING.md

@@ -25,12 +25,13 @@ Here are a few things you can do that will increase the likelihood of your pull
 * Follow the [style guide][style].
 * Write tests. Tests that don't require the VS Code API are located [here](extensions/ql-vscode/test). Integration tests that do require the VS Code API are located [here](extensions/ql-vscode/src/vscode-tests).
 * Keep your change as focused as possible. If there are multiple changes you would like to make that are not dependent upon each other, consider submitting them as separate pull requests.
-* Write a [good commit message](http://tbaggery.com/2008/04/19/a-note-about-git-commit-messages.html).
+* Write a [good commit message](https://tbaggery.com/2008/04/19/a-note-about-git-commit-messages.html).
 
 ## Setting up a local build
 
-Make sure you have a fairly recent version of vscode (>1.32) and are using nodejs
-version >=v10.13.0. (Tested on v10.15.1 and v10.16.0).
+Make sure you have installed recent versions of vscode, node, and npm. Check the `engines` block in [`package.json`](https://github.com/github/vscode-codeql/blob/main/extensions/ql-vscode/package.json) file for compatible versions. Earlier versions may work, but we no longer test against them.
+
+To automatically switch to the correct version of node, we recommend using [nvm](https://github.com/nvm-sh/nvm), which will pick-up the node version from `.nvmrc`.
 
 ### Installing all packages
 
@@ -57,7 +58,6 @@ We recommend that you keep `npm run watch` running in the backgound and you only
 
 1. on first checkout
 2. whenever any of the non-TypeScript resources have changed
-3. on any change to files included in the webview
 
 ### Installing the extension
 
@@ -77,11 +77,25 @@ $ vscode/scripts/code-cli.sh --install-extension dist/vscode-codeql-*.vsix # if
 
 You can use VS Code to debug the extension without explicitly installing it. Just open this directory as a workspace in VS Code, and hit `F5` to start a debugging session.
 
-### Running the unit/integration tests
+### Storybook
 
-Ensure the `CODEQL_PATH` environment variable is set to point to the `codeql` cli executable.
+You can use [Storybook](https://storybook.js.org/) to preview React components outside VSCode. Inside the `extensions/ql-vscode` directory, run:
 
-Outside of vscode, run:
+```shell
+npm run storybook
+```
+
+Your browser should automatically open to the Storybook UI. Stories live in the `src/stories` directory.
+
+Alternatively, you can start Storybook inside of VSCode. There is a VSCode launch configuration for starting Storybook. It can be found in the debug view.
+
+More information about Storybook can be found inside the **Overview** page once you have launched Storybook.
+
+### Running the unit tests and integration tests that do not require a CLI instance
+
+Unit tests and many integration tests do not require a copy of the CodeQL CLI.
+
+Outside of vscode, in the `extensions/ql-vscode` directory, run:
 
 ```shell
 npm run test && npm run integration
@@ -89,39 +103,89 @@ npm run test && npm run integration
 
 Alternatively, you can run the tests inside of vscode. There are several vscode launch configurations defined that run the unit and integration tests. They can all be found in the debug view.
 
+Only the _With CLI_ tests require a CLI instance to run. See below on how to do that.
+
+Running from a terminal, you _must_ set the `TEST_CODEQL_PATH` variable to point to a checkout of the `github/codeql` repository. The appropriate CLI version will be downloaded as part of the test.
+
+### Running the integration tests
+
+You will need to run CLI tests using a task from inside of VS Code called _Launch Integration Tests - With CLI_.
+
+The CLI integration tests require the CodeQL standard libraries in order to run so you will need to clone a local copy of the `github/codeql` repository.
+
+From inside of VSCode, open the `launch.json` file and in the _Launch Integration Tests - With CLI_ task, uncomment the `"${workspaceRoot}/../codeql"` line. If necessary, replace value with a path to your checkout, and then run the task.
+
 ## Releasing (write access required)
 
 1. Double-check the `CHANGELOG.md` contains all desired change comments and has the version to be released with date at the top.
     * Go through all recent PRs and make sure they are properly accounted for.
     * Make sure all changelog entries have links back to their PR(s) if appropriate.
-1. Double-check that the extension `package.json` has the version you intend to release. If you are doing a patch release (as opposed to minor or major version) this should already be correct.
+1. Double-check that the node version we're using matches the one used for VS Code. If it doesn't, you will then need to update the node version in the following files:
+    * `.nvmrc` - this will enable `nvm` to automatically switch to the correct node version when you're in the project folder
+    * `.github/workflows/main.yml` - all the "node-version: <version>" settings
+    * `.github/workflows/release.yml` - the "node-version: <version>" setting
+1. Double-check that the extension `package.json` and `package-lock.json` have the version you intend to release. If you are doing a patch release (as opposed to minor or major version) this should already be correct.
 1. Create a PR for this release:
     * This PR will contain any missing bits from steps 1 and 2. Most of the time, this will just be updating `CHANGELOG.md` with today's date.
     * Create a new branch for the release named after the new version. For example: `v1.3.6`
     * Create a new commit with a message the same as the branch name.
     * Create a PR for this branch.
     * Wait for the PR to be merged into `main`
-1. Trigger a release build on Actions by adding a new tag on branch `main` named after the release, as above. Note that when you push to upstream, you will need to fully qualify the ref. A command like this will work:
+1. Switch to `main` and add a new tag on the `main` branch with your new version (named after the release), e.g.
+    ```bash
+    git checkout main
+    git tag v1.3.6
+    ```
+
+   If you've accidentally created a badly named tag, you can delete it via 
+    ```bash
+    git tag -d badly-named-tag
+    ```
+1. Push the new tag up:
+
+   a. If you're using a fork of the repo:
 
     ```bash
     git push upstream refs/tags/v1.3.6
     ```
+   
+   b. If you're working straight in this repo:
+
+    ```bash
+    git push origin refs/tags/v1.3.6
+    ``` 
+   
+   This will trigger [a release build](https://github.com/github/vscode-codeql/releases) on Actions.
 
     * **IMPORTANT** Make sure you are on the `main` branch and your local checkout is fully updated when you add the tag.
     * If you accidentally add the tag to the wrong ref, you can just force push it to the right one later.
-
 1. Monitor the status of the release build in the `Release` workflow in the Actions tab.
+    * DO NOT approve the "publish" stages of the workflow yet.
 1. Download the VSIX from the draft GitHub release at the top of [the releases page](https://github.com/github/vscode-codeql/releases) that is created when the release build finishes.
 1. Unzip the `.vsix` and inspect its `package.json` to make sure the version is what you expect,
    or look at the source if there's any doubt the right code is being shipped.
-1. Log into the [Visual Studio Marketplace](https://marketplace.visualstudio.com/manage/publishers/github).
-1. Click the `...` menu in the CodeQL row and click **Update**.
-1. Drag the `.vsix` file you downloaded from the GitHub release into the Marketplace and click **Upload**.
-1. Go to the draft GitHub release, click 'Edit', add some summary description, and publish it.
+1. Install the `.vsix` file into your vscode IDE and ensure the extension can load properly. Run a single command (like run query, or add database).
+1. Go to the actions tab of the vscode-codeql repository and select the [Release workflow](https://github.com/github/vscode-codeql/actions?query=workflow%3ARelease).
+    - If there is an authentication failure when publishing, be sure to check that the authentication keys haven't expired. See below.
+1. Approve the deployments of the correct Release workflow. This will automatically publish to Open VSX and VS Code Marketplace.
+1. Go to the draft GitHub release in [the releases tab of the repository](https://github.com/github/vscode-codeql/releases), click 'Edit', add some summary description, and publish it.
 1. Confirm the new release is marked as the latest release at <https://github.com/github/vscode-codeql/releases>.
 1. If documentation changes need to be published, notify documentation team that release has been made.
 1. Review and merge the version bump PR that is automatically created by Actions.
 
+## Secrets and authentication for publishing
+
+Repository administrators, will need to manage the authentication keys for publishing to the VS Code marketplace and Open VSX. Each requires an authentication token. The VS Code marketplace token expires yearly.
+
+To regenerate the Open VSX token:
+
+1. Log in to the [user settings page on Open VSX](https://open-vsx.org/user-settings/namespaces).
+1. Make sure you are a member of the GitHub namespace.
+1. Go to the [Access Tokens](https://open-vsx.org/user-settings/tokens) page and generate a new token.
+1. Update the secret in the `publish-open-vsx` environment in the project settings.
+
+To regenerate the VSCode Marketplace token, please see our internal documentation. Note that Azure DevOps PATs expire every 90 days and must be regenerated.
+
 ## Resources
 
 * [How to Contribute to Open Source](https://opensource.guide/how-to-contribute/)

README.md

@@ -16,7 +16,6 @@ To see what has changed in the last few versions of the extension, see the [Chan
 * Provides an easy way to run queries from the large, open source repository of [CodeQL security queries](https://github.com/github/codeql).
 * Adds IntelliSense to support you writing and editing your own CodeQL query and library files.
 
-
 ## Project goals and scope
 
 This project will track new feature development in CodeQL and, whenever appropriate, bring that functionality to the Visual Studio Code experience.

extensions/ql-vscode/.eslintrc.js

@@ -10,7 +10,7 @@ module.exports = {
     node: true,
     es6: true,
   },
-  extends: ["eslint:recommended", "plugin:@typescript-eslint/recommended"],
+  extends: ["eslint:recommended", "plugin:@typescript-eslint/recommended", "plugin:jest-dom/recommended"],
   rules: {
     "@typescript-eslint/no-use-before-define": 0,
     "@typescript-eslint/no-unused-vars": [
@@ -22,8 +22,10 @@ module.exports = {
       },
     ],
     "@typescript-eslint/explicit-function-return-type": "off",
+    "@typescript-eslint/explicit-module-boundary-types": "off",
     "@typescript-eslint/no-non-null-assertion": "off",
     "@typescript-eslint/no-explicit-any": "off",
+    "@typescript-eslint/no-floating-promises": [ "error", { ignoreVoid: true } ],
     "prefer-const": ["warn", { destructuring: "all" }],
     indent: "off",
     "@typescript-eslint/indent": "off",

extensions/ql-vscode/.npmrc

@@ -0,0 +1,2 @@
+# Storybook requires this option to be set. See https://github.com/storybookjs/storybook/issues/18298
+legacy-peer-deps=true

extensions/ql-vscode/.nvmrc

@@ -0,0 +1 @@
+v16.14.2

extensions/ql-vscode/.storybook/main.ts

@@ -0,0 +1,19 @@
+import type { StorybookConfig } from '@storybook/core-common';
+
+const config: StorybookConfig = {
+  stories: [
+    '../src/**/*.stories.mdx',
+    '../src/**/*.stories.@(js|jsx|ts|tsx)'
+  ],
+  addons: [
+    '@storybook/addon-links',
+    '@storybook/addon-essentials',
+    '@storybook/addon-interactions'
+  ],
+  framework: '@storybook/react',
+  core: {
+    builder: '@storybook/builder-webpack5'
+  }
+};
+
+module.exports = config;

extensions/ql-vscode/.storybook/manager.ts

@@ -0,0 +1,7 @@
+import { addons } from '@storybook/addons';
+import { themes } from '@storybook/theming';
+
+addons.setConfig({
+  theme: themes.dark,
+  enableShortcuts: false,
+});

extensions/ql-vscode/.storybook/preview.ts

@@ -0,0 +1,38 @@
+import { themes } from '@storybook/theming';
+import { action } from '@storybook/addon-actions';
+
+// Allow all stories/components to use Codicons
+import '@vscode/codicons/dist/codicon.css';
+
+import '../src/stories/vscode-theme.css';
+
+// https://storybook.js.org/docs/react/configure/overview#configure-story-rendering
+export const parameters = {
+  // All props starting with `on` will automatically receive an action as a prop
+  actions: { argTypesRegex: "^on[A-Z].*" },
+  // All props matching these names will automatically get the correct control
+  controls: {
+    matchers: {
+      color: /(background|color)$/i,
+      date: /Date$/,
+    },
+  },
+  // Use a dark theme to be aligned with VSCode
+  docs: {
+    theme: themes.dark,
+  },
+  backgrounds: {
+    default: 'dark',
+    values: [
+      {
+        name: 'dark',
+        value: '#1e1e1e',
+      },
+    ],
+  }
+};
+
+(window as any).acquireVsCodeApi = () => ({
+  postMessage: action('post-vscode-message'),
+  setState: action('set-vscode-state'),
+});

extensions/ql-vscode/CHANGELOG.md

@@ -1,5 +1,244 @@
 # CodeQL for Visual Studio Code: Changelog
 
+## 1.7.2 - 14 October 2022
+
+- Fix a bug where results created in older versions were thought to be unsuccessful. [#1605](https://github.com/github/vscode-codeql/pull/1605)
+
+## 1.7.1 - 12 October 2022
+
+- Fix a bug where it was not possible to add a database folder if the folder name starts with `db-`. [#1565](https://github.com/github/vscode-codeql/pull/1565)
+- Ensure the results view opens in an editor column beside the currently active editor. [#1557](https://github.com/github/vscode-codeql/pull/1557)
+
+## 1.7.0 - 20 September 2022
+
+- Remove ability to download databases from LGTM. [#1467](https://github.com/github/vscode-codeql/pull/1467)
+- Remove the ability to manually upgrade databases from the context menu on databases. Databases are non-destructively upgraded automatically so for most users this was not needed. For advanced users this is still available in the Command Palette. [#1501](https://github.com/github/vscode-codeql/pull/1501)
+- Always restart the query server after a manual database upgrade. This avoids a bug in the query server where an invalid dbscheme was being retained in memory after an upgrade. [#1519](https://github.com/github/vscode-codeql/pull/1519)
+
+## 1.6.12 - 1 September 2022
+
+- Add ability for users to download databases directly from GitHub. [#1485](https://github.com/github/vscode-codeql/pull/1485)
+- Fix a race condition that could cause a failure to open the evaluator log when running a query. [#1490](https://github.com/github/vscode-codeql/pull/1490)
+- Fix an error when running a query with an older version of the CodeQL CLI. [#1490](https://github.com/github/vscode-codeql/pull/1490)
+
+## 1.6.11 - 25 August 2022
+
+No user facing changes.
+
+## 1.6.10 - 9 August 2022
+
+No user facing changes.
+
+## 1.6.9 - 20 July 2022
+
+No user facing changes.
+
+## 1.6.8 - 29 June 2022
+
+- Fix a bug where quick queries cannot be compiled if the core libraries are not in the workspace. [#1411](https://github.com/github/vscode-codeql/pull/1411)
+- Fix a bug where quick evaluation of library files would display an error message when using CodeQL CLI v2.10.0. [#1412](https://github.com/github/vscode-codeql/pull/1412)
+
+## 1.6.7 - 15 June 2022
+
+- Prints end-of-query evaluator log summaries to the Query Log. [#1349](https://github.com/github/vscode-codeql/pull/1349)
+- Be consistent about casing in Query History menu. [#1369](https://github.com/github/vscode-codeql/pull/1369)
+- Fix quoting string columns in exported CSV results. [#1379](https://github.com/github/vscode-codeql/pull/1379)
+
+## 1.6.6 - 17 May 2022
+
+No user facing changes.
+
+## 1.6.5 - 25 April 2022
+
+- Re-enable publishing to open-vsx. [#1285](https://github.com/github/vscode-codeql/pull/1285)
+
+## 1.6.4 - 6 April 2022
+
+No user facing changes.
+
+## 1.6.3 - 4 April 2022
+
+- Fix a bug where the AST viewer was not synchronizing its selected node when the editor selection changes. [#1230](https://github.com/github/vscode-codeql/pull/1230)
+- Avoid synchronizing the `codeQL.cli.executablePath` setting. [#1252](https://github.com/github/vscode-codeql/pull/1252)
+- Open the directory in the finder/explorer (instead of just highlighting it) when running the "Open query directory" command from the query history view. [#1235](https://github.com/github/vscode-codeql/pull/1235)
+- Ensure query label in the query history view changes are persisted across restarts. [#1235](https://github.com/github/vscode-codeql/pull/1235)
+- Prints end-of-query evaluator log summaries to the Query Server Console. [#1264](https://github.com/github/vscode-codeql/pull/1264)
+
+## 1.6.1 - 17 March 2022
+
+No user facing changes.
+
+## 1.6.0 - 7 March 2022
+
+- Fix a bug where database upgrades could not be resolved if some of the target pack's dependencies are outside of the workspace. [#1138](https://github.com/github/vscode-codeql/pull/1138)
+- Open the query server logs for query errors (instead of the extension log). This will make it easier to track down query errors. [#1158](https://github.com/github/vscode-codeql/pull/1158)
+- Fix a bug where queries took a long time to run if there are no folders in the workspace. [#1157](https://github.com/github/vscode-codeql/pull/1157)
+- [BREAKING CHANGE] The `codeQL.runningQueries.customLogDirectory` setting is deprecated and no longer has any function. Instead, all query log files will be stored in the query history directory, next to the query results. [#1178](https://github.com/github/vscode-codeql/pull/1178)
+- Add a _Open query directory_ command for query items. This command opens the directory containing all artifacts for a query. [#1179](https://github.com/github/vscode-codeql/pull/1179)
+- Add options to display evaluator logs for a given query run. Some information that was previously found in the query server output may now be found here. [#1186](https://github.com/github/vscode-codeql/pull/1186)
+
+## 1.5.11 - 10 February 2022
+
+- Fix a bug where invoking _View AST_ from the file explorer would not view the selected file. Instead it would view the active editor. Also, prevent the _View AST_ from appearing if the current selection includes a directory or multiple files. [#1113](https://github.com/github/vscode-codeql/pull/1113)
+- Add query history items as soon as a query is run, including new icons for each history item. [#1094](https://github.com/github/vscode-codeql/pull/1094)
+- Save query history items across restarts. Items will be saved for 30 days and can be overwritten by setting the `codeQL.queryHistory.ttl` configuration setting. [#1130](https://github.com/github/vscode-codeql/pull/1130)
+- Allow in-progress query items to be cancelled from the query history view. [#1105](https://github.com/github/vscode-codeql/pull/1105)
+
+## 1.5.10 - 25 January 2022
+
+- Fix a bug where the results view moved column even when it was already visible. [#1070](https://github.com/github/vscode-codeql/pull/1070)
+- Add packaging-related commands. _CodeQL: Download Packs_ downloads query packs from the package registry that can be run locally, and _CodeQL: Install Pack Dependencies_ installs dependencies for packs in your workspace. [#1076](https://github.com/github/vscode-codeql/pull/1076)
+
+## 1.5.9 - 17 December 2021
+
+- Avoid creating a third column when opening the results view. The results view will always open to the right of the active editor, unless the active editor is in the rightmost editor column. In that case open in the leftmost column. [#1037](https://github.com/github/vscode-codeql/pull/1037)
+- Add a CodeLens to make the Quick Evaluation command more accessible. Click the `Quick Evaluation` prompt above a predicate definition in the editor to evaluate that predicate on its own. You can enable/disable this feature in the `codeQL.runningQueries.quickEvalCodelens` setting. [#1035](https://github.com/github/vscode-codeql/pull/1035) & [#1052](https://github.com/github/vscode-codeql/pull/1052)
+- Fix a bug where the _Alerts_ option would show in the results view even if there is no alerts table available. [#1038](https://github.com/github/vscode-codeql/pull/1038)
+
+## 1.5.8 - 2 December 2021
+
+- Emit a more explicit error message when a user tries to add a database with an unzipped source folder to the workspace. [#1021](https://github.com/github/vscode-codeql/pull/1021)
+- Ensure `src.zip` archives are used as the canonical source instead of `src` folders when importing databases. [#1025](https://github.com/github/vscode-codeql/pull/1025)
+
+## 1.5.7 - 23 November 2021
+
+- Fix the _CodeQL: Open Referenced File_ command for Windows systems. [#979](https://github.com/github/vscode-codeql/pull/979)
+- Support large SARIF results files (>4GB) without crashing VS Code. [#1004](https://github.com/github/vscode-codeql/pull/1004)
+- Fix a bug that shows 'Set current database' when hovering over the currently selected database in the databases view. [#976](https://github.com/github/vscode-codeql/pull/976)
+- Fix a bug with importing large databases. Databases over 4GB can now be imported directly from LGTM or from a zip file. This functionality is only available when using CodeQL CLI version 2.6.0 or later. [#971](https://github.com/github/vscode-codeql/pull/971)
+- Replace certain control codes (`U+0000` - `U+001F`) with their corresponding control labels (`U+2400` - `U+241F`) in the results view. [#963](https://github.com/github/vscode-codeql/pull/963)
+- Allow case-insensitive project slugs for GitHub repositories when adding a CodeQL database from LGTM. [#978](https://github.com/github/vscode-codeql/pull/961)
+- Add a _CodeQL: Preview Query Help_ command to generate Markdown previews of `.qhelp` query help files. This command should only be run in trusted workspaces. See [the CodeQL CLI docs](https://codeql.github.com/docs/codeql-cli/testing-query-help-files) for more information about query help. [#988](https://github.com/github/vscode-codeql/pull/988)
+- Make "Open Referenced File" command accessible from the active editor menu. [#989](https://github.com/github/vscode-codeql/pull/989)
+- Fix a bug where result set names in the result set drop-down were disappearing when viewing a sorted table. [#1007](https://github.com/github/vscode-codeql/pull/1007)
+- Allow query result locations with 0 as the end column value. These are treated as the first column in the line. [#1002](https://github.com/github/vscode-codeql/pull/1002)
+
+## 1.5.6 - 07 October 2021
+
+- Add progress messages to LGTM download option. This makes the two-step process (selecting a project, then selecting a language) more clear. [#960](https://github.com/github/vscode-codeql/pull/960)
+- Remove line about selecting a language from the dropdown when downloading database from LGTM. This makes the download progress visible when the popup is not expanded. [#957](https://github.com/github/vscode-codeql/pull/957)
+- Fix a bug where copying the version information fails when a CodeQL CLI cannot be found. [#958](https://github.com/github/vscode-codeql/pull/958)
+- Avoid a race condition when deleting databases that can cause occasional errors. [#959](https://github.com/github/vscode-codeql/pull/959)
+- Update CodeQL logos. [#965](https://github.com/github/vscode-codeql/pull/965)
+
+## 1.5.5 - 08 September 2021
+
+- Fix bug where a query is sometimes run before the file is saved. [#947](https://github.com/github/vscode-codeql/pull/947)
+- Fix broken contextual queries, including _View AST_. [#949](https://github.com/github/vscode-codeql/pull/949)
+
+## 1.5.4 - 02 September 2021
+
+- Add support for filename pattern in history view. [#930](https://github.com/github/vscode-codeql/pull/930)
+- Add an option _View Results (CSV)_ to view the results of a non-alert query. The existing options for alert queries have been renamed to _View Alerts_ to avoid confusion. [#929](https://github.com/github/vscode-codeql/pull/929)
+- Allow users to specify the number of paths to display for each alert. [#931](https://github.com/github/vscode-codeql/pull/931)
+- Adjust pagination controls in _CodeQL Query Results_ to always be visible [#936](https://github.com/github/vscode-codeql/pull/936)
+- Fix bug where _View AST_ fails due to recent refactoring in the standard library and query packs. [#939](https://github.com/github/vscode-codeql/pull/939)
+
+## 1.5.3 - 18 August 2021
+
+- Add a command _CodeQL: Run Query on Multiple Databases_, which lets users select multiple databases to run a query on. [#898](https://github.com/github/vscode-codeql/pull/898)
+- Autodetect what language a query targets. This refines the _CodeQL: Run Query on Multiple Databases_ command to only show relevant databases. [#915](https://github.com/github/vscode-codeql/pull/915)
+- Adjust test log output to display diffs only when comparing failed test results with expected test results. [#920](https://github.com/github/vscode-codeql/pull/920)
+
+## 1.5.2 - 13 July 2021
+
+- Add the _Add Database Source to Workspace_ command to the right-click context menu in the databases view. This lets users re-add a database's source folder to the workspace and browse the source code. [#891](https://github.com/github/vscode-codeql/pull/891)
+- Fix markdown rendering in the description of the `codeQL.cli.executablePath` setting. [#908](https://github.com/github/vscode-codeql/pull/908)
+- Fix the _Open Query Results_ command in the query history view. [#909](https://github.com/github/vscode-codeql/pull/909)
+
+## 1.5.1 - 23 June 2021
+
+No user facing changes.
+
+## 1.5.0 - 14 June 2021
+
+- Display CodeQL CLI version being downloaded during an upgrade. [#862](https://github.com/github/vscode-codeql/pull/862)
+- Display a helpful message and link to documentation when a query produces no results. [#866](https://github.com/github/vscode-codeql/pull/866)
+- Refresh test databases automatically after a test run. [#868](https://github.com/github/vscode-codeql/pull/868)
+- Allow users to specify a custom directory for storing query server logs (`codeQL.runningQueries.customLogDirectory`). The extension will not delete these logs automatically. [#863](https://github.com/github/vscode-codeql/pull/863)
+- Support the VS Code [Workspace Trust feature](https://code.visualstudio.com/docs/editor/workspace-trust). This extension is now enabled in untrusted workspaces, but it restricts commands that contain arbitrary paths. [#861](https://github.com/github/vscode-codeql/pull/861)
+- Allow the `codeQL.cli.executablePath` configuration setting to be set in workspace-scoped configuration files. This means that each workspace can now specify its own CodeQL CLI compiler, a feature that is unblocked due to implementing Workspace Trust. [#861](https://github.com/github/vscode-codeql/pull/861)
+
+## 1.4.8 - 05 May 2021
+
+- Copy version information to the clipboard when a user clicks the CodeQL section of the status bar. [#845](https://github.com/github/vscode-codeql/pull/845)
+- Ensure changes in directories that contain tests will be properly updated in the test explorer. [#846](https://github.com/github/vscode-codeql/pull/846)
+- Remind users to choose a language when downloading a database from LGTM. [#852](https://github.com/github/vscode-codeql/pull/852)
+
+## 1.4.7 - 23 April 2021
+
+- Fix a bug that prevented the results view from being loaded. [#842](https://github.com/github/vscode-codeql/pull/842)
+
+## 1.4.6 - 21 April 2021
+
+- Avoid showing an error popup when running a query with `@kind table` metadata. [#814](https://github.com/github/vscode-codeql/pull/814)
+- Add an option to jump from a .qlref file to the .ql file it references. [#815](https://github.com/github/vscode-codeql/pull/815)
+- Avoid opening the results panel when a database is deleted. [#831](https://github.com/github/vscode-codeql/pull/831)
+- Forward all query metadata to the CLI when interpreting results. [#838](https://github.com/github/vscode-codeql/pull/838)
+
+## 1.4.5 - 22 March 2021
+
+- Avoid showing an error popup when user runs a query without `@kind` metadata. [#801](https://github.com/github/vscode-codeql/pull/801)
+- Fix running of tests when the `ms-python` extension is installed. [#803](https://github.com/github/vscode-codeql/pull/803)
+
+## 1.4.4 - 19 March 2021
+
+- Introduce evaluator options for saving intermediate results to the disk cache (`codeQL.runningQueries.saveCache`) and for limiting the size of this cache (`codeQL.runningQueries.cacheSize`). [#778](https://github.com/github/vscode-codeql/pull/778)
+- Respect the `codeQL.runningQueries.numberOfThreads` setting when creating SARIF files during result interpretation. [#771](https://github.com/github/vscode-codeql/pull/771)
+- Allow using raw LGTM project slugs for fetching LGTM databases. [#769](https://github.com/github/vscode-codeql/pull/769)
+- Better error messages when BQRS interpretation fails to produce SARIF. [#770](https://github.com/github/vscode-codeql/pull/770)
+- Implement sorting of the query history view by name, date, and results count. [#777](https://github.com/github/vscode-codeql/pull/777)
+- Add a configuration option to pass additional arguments to the CLI when running tests. [#785](https://github.com/github/vscode-codeql/pull/785)
+- Introduce option to view query results as CSV. [#784](https://github.com/github/vscode-codeql/pull/784)
+- Add some snippets for commonly used QL statements. [#782](https://github.com/github/vscode-codeql/pull/782)
+- More descriptive error messages on QL test failures. [#788](https://github.com/github/vscode-codeql/pull/788)
+
+## 1.4.3 - 22 February 2021
+
+- Avoid displaying an error when removing orphaned databases and the storage folder does not exist. [#748](https://github.com/github/vscode-codeql/pull/748)
+- Add better error messages when AST Viewer is unable to create an AST. [#753](https://github.com/github/vscode-codeql/pull/753)
+- Cache AST viewing operations so that subsequent calls to view the AST of a single file will be extremely fast. [#753](https://github.com/github/vscode-codeql/pull/753)
+- Ensure CodeQL version in status bar updates correctly when version changes. [#754](https://github.com/github/vscode-codeql/pull/754)
+- Avoid deleting the quick query file when it is re-opened. [#747](https://github.com/github/vscode-codeql/pull/747)
+
+## 1.4.2 - 2 February 2021
+
+- Add a status bar item for the CodeQL CLI to show the current version. [#741](https://github.com/github/vscode-codeql/pull/741)
+- Fix version constraint for flagging CLI support of non-destructive updates. [#744](https://github.com/github/vscode-codeql/pull/744)
+- Add a _More Information_ button in the telemetry popup that opens the [telemetry documentation](https://codeql.github.com/docs/codeql-for-visual-studio-code/about-telemetry-in-codeql-for-visual-studio-code) in a browser tab. [#742](https://github.com/github/vscode-codeql/pull/742)
+
+## 1.4.1 - 29 January 2021
+
+- Reword the telemetry modal dialog box. [#738](https://github.com/github/vscode-codeql/pull/738)
+
+## 1.4.0 - 29 January 2021
+
+- Fix bug where databases are not reregistered when the query server restarts. [#734](https://github.com/github/vscode-codeql/pull/734)
+- Fix bug where upgrade requests were erroneously being marked as failed. [#734](https://github.com/github/vscode-codeql/pull/734)
+- On a strictly opt-in basis, collect anonymized usage data from the VS Code extension, helping improve CodeQL's usability and performance. See the [telemetry documentation](https://codeql.github.com/docs/codeql-for-visual-studio-code/about-telemetry-in-codeql-for-visual-studio-code) for more information on exactly what data is collected and what it is used for. [#611](https://github.com/github/vscode-codeql/pull/611)
+
+## 1.3.10 - 20 January 2021
+
+- Include the full stack in error log messages to help with debugging. [#726](https://github.com/github/vscode-codeql/pull/726)
+
+## 1.3.9 - 12 January 2021
+
+- No changes visible to end users.
+
+## 1.3.8 - 17 December 2020
+
+- Ensure databases are unlocked when removing them from the workspace. This will ensure that after a database is removed from VS Code, queries can be run on it from the command line without restarting the IDE. Requires CodeQL CLI 2.4.1 or later. [#681](https://github.com/github/vscode-codeql/pull/681)
+- Fix bug when removing databases where sometimes the source folder would not also be removed from the workspace or the database files would not be deleted from the workspace storage location. [#692](https://github.com/github/vscode-codeql/pull/692)
+- Query results with no string representation will now be displayed with placeholder text in query results. Previously, they were omitted. [#694](https://github.com/github/vscode-codeql/pull/694)
+- Add a label for the language of a database in the databases view. This will only take effect for new databases created with the CodeQL CLI v2.4.1 or later. [#697](https://github.com/github/vscode-codeql/pull/697)
+- Add clearer error message when running a query using a missing or invalid qlpack. [#702](https://github.com/github/vscode-codeql/pull/702)
+- Add clearer error message when trying to run a command from the query history view if no item in the history is selected. [#702](https://github.com/github/vscode-codeql/pull/702)
+- Fix a bug where it is not possible to download some database archives. This fix specifically addresses large archives and archives whose central directories do not align with file headers. [#700](https://github.com/github/vscode-codeql/pull/700)
+- Avoid error dialogs when QL test discovery or database cleanup encounters a missing directory. [#706](https://github.com/github/vscode-codeql/pull/706)
+- Add descriptive text and a link in the results view. [#711](https://github.com/github/vscode-codeql/pull/711)
+- Fix the _Set Label_ command in the query history view. [#710](https://github.com/github/vscode-codeql/pull/710)
+- Add the _CodeQL: View AST_ command to the right-click context menu when a source file in a database source archive is open in the editor. [#712](https://github.com/github/vscode-codeql/pull/712)
+
 ## 1.3.7 - 24 November 2020
 
 - Editors opened by navigating from the results view are no longer opened in _preview mode_. Now they are opened as a persistent editor. [#630](https://github.com/github/vscode-codeql/pull/630)

extensions/ql-vscode/README.md

@@ -1,6 +1,6 @@
 # CodeQL extension for Visual Studio Code
 
-This project is an extension for Visual Studio Code that adds rich language support for [CodeQL](https://help.semmle.com/codeql) and allows you to easily find problems in codebases. In particular, the extension:
+This project is an extension for Visual Studio Code that adds rich language support for [CodeQL](https://codeql.github.com/docs/) and allows you to easily find problems in codebases. In particular, the extension:
 
 - Enables you to use CodeQL to query databases generated from source code.
 - Shows the flow of data through the results of path queries, which is essential for triaging security results.
@@ -12,7 +12,7 @@ To see what has changed in the last few versions of the extension, see the [Chan
 ## Quick start overview
 
 The information in this `README` file describes the quickest way to start using CodeQL.
-For information about other configurations, see the separate [CodeQL help](https://help.semmle.com/codeql/codeql-for-vscode.html).
+For information about other configurations, see the separate [CodeQL help](https://codeql.github.com/docs/codeql-for-visual-studio-code/).
 
 ### Quick start: Installing and configuring the extension
 
@@ -22,7 +22,7 @@ For information about other configurations, see the separate [CodeQL help](https
 
 ### Quick start: Using CodeQL
 
-1. [Import a database from LGTM](#importing-a-database-from-lgtm).
+1. [Import a database from GitHub](#importing-a-database-from-github).
 1. [Run a query](#running-a-query).
 
 ---
@@ -40,9 +40,9 @@ The CodeQL extension requires a minimum of Visual Studio Code 1.39. Older versio
 
 ### Checking access to the CodeQL CLI
 
-The extension uses the [CodeQL CLI](https://help.semmle.com/codeql/codeql-cli.html) to compile and run queries. The extension automatically manages access to the CLI for you by default (recommended). To check for updates to the CodeQL CLI, you can use the **CodeQL: Check for CLI Updates** command.
+The extension uses the [CodeQL CLI](https://codeql.github.com/docs/codeql-cli/) to compile and run queries. The extension automatically manages access to the CLI for you by default (recommended). To check for updates to the CodeQL CLI, you can use the **CodeQL: Check for CLI Updates** command.
 
-If you want to override the default behavior and use a CodeQL CLI that's already on your machine, see [Configuring access to the CodeQL CLI](https://help.semmle.com/codeql/codeql-for-vscode/procedures/setting-up.html#configuring-access-to-the-codeql-cli).
+If you want to override the default behavior and use a CodeQL CLI that's already on your machine, see [Configuring access to the CodeQL CLI](https://codeql.github.com/docs/codeql-for-visual-studio-code/setting-up-codeql-in-visual-studio-code/#configuring-access-to-the-codeql-cli).
 
 If you have any difficulty with CodeQL CLI access, see the **CodeQL Extension Log** in the **Output** view for any error messages.
 
@@ -52,7 +52,7 @@ When you're working with CodeQL, you need access to the standard CodeQL librarie
 Initially, we recommend that you clone and use the ready-to-use [starter workspace](https://github.com/github/vscode-codeql-starter/).
 This includes libraries and queries for the main supported languages, with folders set up ready for your custom queries. After cloning the workspace (use `git clone --recursive`), you can use it in the same way as any other VS Code workspace—with the added advantage that you can easily update the CodeQL libraries.
 
-For information about configuring an existing workspace for CodeQL, [see the documentation](https://help.semmle.com/codeql/codeql-for-vscode/procedures/setting-up.html#updating-an-existing-workspace-for-codeql).
+For information about configuring an existing workspace for CodeQL, [see the documentation](https://codeql.github.com/docs/codeql-for-visual-studio-code/setting-up-codeql-in-visual-studio-code/#updating-an-existing-workspace-for-codeql).
 
 ## Upgrading CodeQL standard libraries
 
@@ -73,18 +73,19 @@ If you're using your own clone of the CodeQL standard libraries, you can do a `g
 
 You can find all the commands contributed by the extension in the Command Palette (**Ctrl+Shift+P** or **Cmd+Shift+P**) by typing `CodeQL`, many of them are also accessible through the interface, and via keyboard shortcuts.
 
-### Importing a database from LGTM
+### Importing a database from GitHub
 
-While you can use the [CodeQL CLI to create your own databases](https://help.semmle.com/codeql/codeql-cli/procedures/create-codeql-database.html), the simplest way to start is by downloading a database from LGTM.com.
+While you can use the [CodeQL CLI to create your own databases](https://codeql.github.com/docs/codeql-cli/creating-codeql-databases/), the simplest way to start is by downloading a database from GitHub.com.
 
-1. Open [LGTM.com](https://lgtm.com/#explore) in your browser.
-1. Search for a project you're interested in, for example [Apache Kafka](https://lgtm.com/projects/g/apache/kafka).
-1. Copy the link to that project, for example `https://lgtm.com/projects/g/apache/kafka`.
-1. In VS Code, open the Command Palette and choose the **CodeQL: Download Database from LGTM** command.
+1. Find a project that you're interested in on GitHub.com, for example [Apache Kafka](https://github.com/apache/kafka).
+1. Copy the link to that project, for example `https://github.com/apache/kafka`.
+1. In VS Code, open the Command Palette and choose the **CodeQL: Download Database from GitHub** command.
 1. Paste the link you copied earlier.
 1. Select the language for the database you want to download (only required if the project has databases for multiple languages).
 1. Once the CodeQL database has been imported, it is displayed in the Databases view.
 
+For more information, see [Choosing a database](https://codeql.github.com/docs/codeql-for-visual-studio-code/analyzing-your-projects/#choosing-a-database) on codeql.github.com.
+
 ### Running a query
 
 The instructions below assume that you're using the CodeQL starter workspace, or that you've added the CodeQL libraries and queries repository to your workspace.
@@ -100,13 +101,17 @@ If there are any problems running a query, a notification is displayed in the bo
 
 ## What next?
 
-For more information about the CodeQL extension, [see the documentation](https://help.semmle.com/codeql/codeql-for-vscode.html). Otherwise, you could:
+For more information about the CodeQL extension, [see the documentation](https://codeql.github.com/docs/codeql-for-visual-studio-code/). Otherwise, you could:
 
-- [Create a database for a different codebase](https://help.semmle.com/codeql/codeql-cli/procedures/create-codeql-database.html).
+- [Create a database for a different codebase](https://codeql.github.com/docs/codeql-cli/creating-codeql-databases/).
 - [Try out variant analysis](https://help.semmle.com/QL/learn-ql/ql-training.html).
-- [Learn more about CodeQL](https://help.semmle.com/QL/learn-ql/).
+- [Learn more about CodeQL](https://codeql.github.com/docs/).
 - [Read how security researchers use CodeQL to find CVEs](https://securitylab.github.com/research).
 
 ## License
 
 The CodeQL extension for Visual Studio Code is [licensed](LICENSE.md) under the MIT License. The version of CodeQL used by the CodeQL extension is subject to the [GitHub CodeQL Terms & Conditions](https://securitylab.github.com/tools/codeql/license).
+
+## Data and Telemetry
+
+If you specifically opt-in to permit GitHub to do so, GitHub will collect usage data and metrics for the purposes of helping the core developers to improve the CodeQL extension for VS Code. This data will not be shared with any parties outside of GitHub. IP addresses and installation IDs will be retained for a maximum of 30 days. Anonymous data will be retained for a maximum of 180 days. For more information about telemetry, [see the documentation](https://codeql.github.com/docs/codeql-for-visual-studio-code/about-telemetry-in-codeql-for-visual-studio-code).

extensions/ql-vscode/gulpfile.ts/appInsights.ts

@@ -0,0 +1,17 @@
+import * as gulp from 'gulp';
+// eslint-disable-next-line @typescript-eslint/no-var-requires
+const replace = require('gulp-replace');
+
+/** Inject the application insights key into the telemetry file */
+export function injectAppInsightsKey() {
+  if (!process.env.APP_INSIGHTS_KEY) {
+    // noop
+    console.log('APP_INSIGHTS_KEY environment variable is not set. So, cannot inject it into the application.');
+    return Promise.resolve();
+  }
+
+  // replace the key
+  return gulp.src(['out/telemetry.js'])
+    .pipe(replace(/REPLACE-APP-INSIGHTS-KEY/, process.env.APP_INSIGHTS_KEY))
+    .pipe(gulp.dest('out/'));
+}

extensions/ql-vscode/gulpfile.ts/deploy.ts

@@ -1,5 +1,4 @@
 import * as fs from 'fs-extra';
-import * as jsonc from 'jsonc-parser';
 import * as path from 'path';
 
 export interface DeployedPackage {
@@ -13,6 +12,7 @@ const packageFiles = [
   'CHANGELOG.md',
   'README.md',
   'language-configuration.json',
+  'snippets.json',
   'media',
   'node_modules',
   'out'
@@ -27,7 +27,7 @@ async function copyPackage(sourcePath: string, destPath: string): Promise<void>
 
 export async function deployPackage(packageJsonPath: string): Promise<DeployedPackage> {
   try {
-    const packageJson: any = jsonc.parse(await fs.readFile(packageJsonPath, 'utf8'));
+    const packageJson: any = JSON.parse(await fs.readFile(packageJsonPath, 'utf8'));
 
     // Default to development build; use flag --release to indicate release build.
     const isDevBuild = !process.argv.includes('--release');

extensions/ql-vscode/gulpfile.ts/index.ts

@@ -1,10 +1,27 @@
 import * as gulp from 'gulp';
-import { compileTypeScript, watchTypeScript, copyViewCss } from './typescript';
+import { compileTypeScript, watchTypeScript, cleanOutput } from './typescript';
 import { compileTextMateGrammar } from './textmate';
 import { copyTestData } from './tests';
-import { compileView } from './webpack';
+import { compileView, watchView } from './webpack';
 import { packageExtension } from './package';
+import { injectAppInsightsKey } from './appInsights';
 
-export const buildWithoutPackage = gulp.parallel(compileTypeScript, compileTextMateGrammar, compileView, copyTestData, copyViewCss);
-export { compileTextMateGrammar, watchTypeScript, compileTypeScript };
-exports.default = gulp.series(exports.buildWithoutPackage, packageExtension);
+export const buildWithoutPackage =
+  gulp.series(
+    cleanOutput,
+    gulp.parallel(
+      compileTypeScript, compileTextMateGrammar, compileView, copyTestData
+    )
+  );
+
+export {
+  cleanOutput,
+  compileTextMateGrammar,
+  watchTypeScript,
+  watchView,
+  compileTypeScript,
+  copyTestData,
+  injectAppInsightsKey,
+  compileView,
+};
+export default gulp.series(buildWithoutPackage, injectAppInsightsKey, packageExtension);

extensions/ql-vscode/gulpfile.ts/tests.ts

@@ -1,6 +1,17 @@
 import * as gulp from 'gulp';
 
 export function copyTestData() {
+  copyNoWorkspaceData();
+  copyCliIntegrationData();
+  return Promise.resolve();
+}
+
+function copyNoWorkspaceData() {
   return gulp.src('src/vscode-tests/no-workspace/data/**/*')
     .pipe(gulp.dest('out/vscode-tests/no-workspace/data'));
 }
+
+function copyCliIntegrationData() {
+  return gulp.src('src/vscode-tests/cli-integration/data/**/*')
+    .pipe(gulp.dest('out/vscode-tests/cli-integration/data'));
+}

extensions/ql-vscode/gulpfile.ts/textmate.ts

@@ -219,14 +219,14 @@ function transformFile(yaml: any) {
 }
 
 export function transpileTextMateGrammar() {
-  return through.obj((file: Vinyl, _encoding: string, callback: Function): void => {
+  return through.obj((file: Vinyl, _encoding: string, callback: (err: string | null, file: Vinyl | PluginError) => void): void => {
     if (file.isNull()) {
       callback(null, file);
     }
     else if (file.isBuffer()) {
       const buf: Buffer = file.contents;
       const yamlText: string = buf.toString('utf8');
-      const jsonData: any = jsYaml.safeLoad(yamlText);
+      const jsonData: any = jsYaml.load(yamlText);
       transformFile(jsonData);
 
       file.contents = Buffer.from(JSON.stringify(jsonData, null, 2), 'utf8');

extensions/ql-vscode/gulpfile.ts/tsconfig.json

@@ -1,11 +1,11 @@
 {
-  "$schema": "http://json.schemastore.org/tsconfig",
+  "$schema": "https://json.schemastore.org/tsconfig",
   "compilerOptions": {
     "declaration": true,
     "strict": true,
     "module": "commonjs",
     "target": "es2017",
-    "lib": ["es6"],
+    "lib": ["ES2021"],
     "moduleResolution": "node",
     "sourceMap": true,
     "rootDir": ".",
@@ -16,7 +16,8 @@
     "noImplicitReturns": true,
     "experimentalDecorators": true,
     "noUnusedLocals": true,
-    "noUnusedParameters": true
+    "noUnusedParameters": true,
+    "esModuleInterop": true
   },
   "include": ["*.ts"]
 }

extensions/ql-vscode/gulpfile.ts/typescript.ts

@@ -2,6 +2,7 @@ import * as colors from 'ansi-colors';
 import * as gulp from 'gulp';
 import * as sourcemaps from 'gulp-sourcemaps';
 import * as ts from 'gulp-typescript';
+import * as del from 'del';
 
 function goodReporter(): ts.reporter.Reporter {
   return {
@@ -20,6 +21,10 @@ function goodReporter(): ts.reporter.Reporter {
 
 const tsProject = ts.createProject('tsconfig.json');
 
+export function cleanOutput() {
+  return tsProject.projectDirectory ? del(tsProject.projectDirectory + '/out/*') : Promise.resolve();
+}
+
 export function compileTypeScript() {
   return tsProject.src()
     .pipe(sourcemaps.init())
@@ -34,9 +39,3 @@ export function compileTypeScript() {
 export function watchTypeScript() {
   gulp.watch('src/**/*.ts', compileTypeScript);
 }
-
-/** Copy CSS files for the results view into the output directory. */
-export function copyViewCss() {
-  return gulp.src('src/view/*.css')
-    .pipe(gulp.dest('out'));
-}

extensions/ql-vscode/gulpfile.ts/webpack.config.ts

@@ -1,11 +1,11 @@
 import * as path from 'path';
 import * as webpack from 'webpack';
+import * as MiniCssExtractPlugin from 'mini-css-extract-plugin';
 
 export const config: webpack.Configuration = {
   mode: 'development',
   entry: {
-    resultsView: './src/view/results.tsx',
-    compareView: './src/compare/view/Compare.tsx',
+    webview: './src/view/webview.tsx'
   },
   output: {
     path: path.resolve(__dirname, '..', 'out'),
@@ -13,7 +13,10 @@ export const config: webpack.Configuration = {
   },
   devtool: 'inline-source-map',
   resolve: {
-    extensions: ['.js', '.ts', '.tsx', '.json']
+    extensions: ['.js', '.ts', '.tsx', '.json'],
+    fallback: {
+      path: require.resolve('path-browserify')
+    }
   },
   module: {
     rules: [
@@ -27,9 +30,7 @@ export const config: webpack.Configuration = {
       {
         test: /\.less$/,
         use: [
-          {
-            loader: 'style-loader'
-          },
+          MiniCssExtractPlugin.loader,
           {
             loader: 'css-loader',
             options: {
@@ -49,17 +50,31 @@ export const config: webpack.Configuration = {
       {
         test: /\.css$/,
         use: [
-          {
-            loader: 'style-loader'
-          },
+          MiniCssExtractPlugin.loader,
           {
             loader: 'css-loader'
           }
         ]
+      },
+      {
+        test: /\.(woff(2)?|ttf|eot)$/,
+        use: [
+          {
+            loader: 'file-loader',
+            options: {
+              name: '[name].[ext]',
+              outputPath: 'fonts/',
+              // We need this to make Webpack use the correct path for the fonts.
+              // Without this, the CSS file will use `url([object Module])`
+              esModule: false
+            }
+          },
+        ],
       }
     ]
   },
   performance: {
     hints: false
-  }
+  },
+  plugins: [new MiniCssExtractPlugin()],
 };

extensions/ql-vscode/gulpfile.ts/webpack.ts

@@ -2,27 +2,50 @@ import * as webpack from 'webpack';
 import { config } from './webpack.config';
 
 export function compileView(cb: (err?: Error) => void) {
-  webpack(config).run((error, stats) => {
+  doWebpack(config, true, cb);
+}
+
+export function watchView(cb: (err?: Error) => void) {
+  const watchConfig = {
+    ...config,
+    watch: true,
+    watchOptions: {
+      aggregateTimeout: 200,
+      poll: 1000,
+    }
+  };
+  doWebpack(watchConfig, false, cb);
+}
+
+function doWebpack(internalConfig: webpack.Configuration, failOnError: boolean, cb: (err?: Error) => void) {
+  const resultCb = (error: Error | undefined, stats?: webpack.Stats) => {
     if (error) {
       cb(error);
     }
-    console.log(stats.toString({
-      errorDetails: true,
-      colors: true,
-      assets: false,
-      builtAt: false,
-      version: false,
-      hash: false,
-      entrypoints: false,
-      timings: false,
-      modules: false,
-      errors: true
-    }));
-    if (stats.hasErrors()) {
-      cb(new Error('Compilation errors detected.'));
-      return;
+    if (stats) {
+      console.log(stats.toString({
+        errorDetails: true,
+        colors: true,
+        assets: false,
+        builtAt: false,
+        version: false,
+        hash: false,
+        entrypoints: false,
+        timings: false,
+        modules: false,
+        errors: true
+      }));
+      if (stats.hasErrors()) {
+        if (failOnError) {
+          cb(new Error('Compilation errors detected.'));
+          return;
+        } else {
+          console.error('Compilation errors detected.');
+        }
+      }
+      cb();
     }
+  };
 
-    cb();
-  });
+  webpack(internalConfig, resultCb);
 }

extensions/ql-vscode/jest.config.js

@@ -0,0 +1,214 @@
+/*
+ * For a detailed explanation regarding each configuration property and type check, visit:
+ * https://jestjs.io/docs/configuration
+ */
+
+module.exports = {
+  // All imported modules in your tests should be mocked automatically
+  // automock: false,
+
+  // Stop running tests after `n` failures
+  // bail: 0,
+
+  // The directory where Jest should store its cached dependency information
+  // cacheDirectory: "/private/var/folders/6m/1394pht172qgd7dmw1fwjk100000gn/T/jest_dx",
+
+  // Automatically clear mock calls, instances, contexts and results before every test
+  // clearMocks: true,
+
+  // Indicates whether the coverage information should be collected while executing the test
+  // collectCoverage: false,
+
+  // An array of glob patterns indicating a set of files for which coverage information should be collected
+  // collectCoverageFrom: undefined,
+
+  // The directory where Jest should output its coverage files
+  // coverageDirectory: undefined,
+
+  // An array of regexp pattern strings used to skip coverage collection
+  // coveragePathIgnorePatterns: [
+  //   "/node_modules/"
+  // ],
+
+  // Indicates which provider should be used to instrument code for coverage
+  coverageProvider: 'v8',
+
+  // A list of reporter names that Jest uses when writing coverage reports
+  // coverageReporters: [
+  //   "json",
+  //   "text",
+  //   "lcov",
+  //   "clover"
+  // ],
+
+  // An object that configures minimum threshold enforcement for coverage results
+  // coverageThreshold: undefined,
+
+  // A path to a custom dependency extractor
+  // dependencyExtractor: undefined,
+
+  // Make calling deprecated APIs throw helpful error messages
+  // errorOnDeprecated: false,
+
+  // The default configuration for fake timers
+  // fakeTimers: {
+  //   "enableGlobally": false
+  // },
+
+  // Force coverage collection from ignored files using an array of glob patterns
+  // forceCoverageMatch: [],
+
+  // A path to a module which exports an async function that is triggered once before all test suites
+  // globalSetup: undefined,
+
+  // A path to a module which exports an async function that is triggered once after all test suites
+  // globalTeardown: undefined,
+
+  // A set of global variables that need to be available in all test environments
+  // globals: {},
+
+  // The maximum amount of workers used to run your tests. Can be specified as % or a number. E.g. maxWorkers: 10% will use 10% of your CPU amount + 1 as the maximum worker number. maxWorkers: 2 will use a maximum of 2 workers.
+  // maxWorkers: "50%",
+
+  // An array of directory names to be searched recursively up from the requiring module's location
+  // moduleDirectories: [
+  //   "node_modules"
+  // ],
+
+  // An array of file extensions your modules use
+  moduleFileExtensions: [
+    'js',
+    'mjs',
+    'cjs',
+    'jsx',
+    'ts',
+    'tsx',
+    'json'
+  ],
+
+  // A map from regular expressions to module names or to arrays of module names that allow to stub out resources with a single module
+  'moduleNameMapper': {
+    '\\.(jpg|jpeg|png|gif|eot|otf|webp|svg|ttf|woff|woff2|mp4|webm|wav|mp3|m4a|aac|oga)$': '<rootDir>/test/__mocks__/fileMock.ts',
+    '\\.(css|less)$': '<rootDir>/test/__mocks__/styleMock.ts'
+  },
+
+  // An array of regexp pattern strings, matched against all module paths before considered 'visible' to the module loader
+  // modulePathIgnorePatterns: [],
+
+  // Activates notifications for test results
+  // notify: false,
+
+  // An enum that specifies notification mode. Requires { notify: true }
+  // notifyMode: "failure-change",
+
+  // A preset that is used as a base for Jest's configuration
+  preset: 'ts-jest',
+
+  // Run tests from one or more projects
+  // projects: undefined,
+
+  // Use this configuration option to add custom reporters to Jest
+  // reporters: undefined,
+
+  // Automatically reset mock state before every test
+  // resetMocks: false,
+
+  // Reset the module registry before running each individual test
+  // resetModules: false,
+
+  // A path to a custom resolver
+  // resolver: undefined,
+
+  // Automatically restore mock state and implementation before every test
+  // restoreMocks: false,
+
+  // The root directory that Jest should scan for tests and modules within
+  // rootDir: undefined,
+
+  // A list of paths to directories that Jest should use to search for files in
+  // roots: [
+  //   "<rootDir>"
+  // ],
+
+  // Allows you to use a custom runner instead of Jest's default test runner
+  // runner: "jest-runner",
+
+  // The paths to modules that run some code to configure or set up the testing environment before each test
+  // setupFiles: [],
+
+  // A list of paths to modules that run some code to configure or set up the testing framework before each test
+  setupFilesAfterEnv: ['<rootDir>/test/jest.setup.ts'],
+
+  // The number of seconds after which a test is considered as slow and reported as such in the results.
+  // slowTestThreshold: 5,
+
+  // A list of paths to snapshot serializer modules Jest should use for snapshot testing
+  // snapshotSerializers: [],
+
+  // The test environment that will be used for testing
+  testEnvironment: 'jsdom',
+
+  // Options that will be passed to the testEnvironment
+  // testEnvironmentOptions: {},
+
+  // Adds a location field to test results
+  // testLocationInResults: false,
+
+  // The glob patterns Jest uses to detect test files
+  testMatch: [
+    '**/__tests__/**/*.[jt]s?(x)'
+  ],
+
+  // An array of regexp pattern strings that are matched against all test paths, matched tests are skipped
+  // testPathIgnorePatterns: [
+  //   "/node_modules/"
+  // ],
+
+  // The regexp pattern or array of patterns that Jest uses to detect test files
+  // testRegex: [],
+
+  // This option allows the use of a custom results processor
+  // testResultsProcessor: undefined,
+
+  // This option allows use of a custom test runner
+  // testRunner: "jest-circus/runner",
+
+  // A map from regular expressions to paths to transformers
+  transform: {
+    '^.+\\.tsx?$': [
+      'ts-jest',
+      {
+        tsconfig: 'src/view/tsconfig.spec.json',
+      },
+    ],
+    'node_modules': [
+      'babel-jest',
+      {
+        presets: [
+          '@babel/preset-env'
+        ],
+        plugins: [
+          '@babel/plugin-transform-modules-commonjs',
+        ]
+      }
+    ]
+  },
+
+  // An array of regexp pattern strings that are matched against all source file paths, matched files will skip transformation
+  'transformIgnorePatterns': [
+    // These use ES modules, so need to be transformed
+    'node_modules/(?!(?:@vscode/webview-ui-toolkit|@microsoft/.+|exenv-es6)/.*)'
+  ],
+
+  // An array of regexp pattern strings that are matched against all modules before the module loader will automatically return a mock for them
+  // unmockedModulePathPatterns: undefined,
+
+  // Indicates whether each individual test should be reported during the run
+  // verbose: undefined,
+
+  // An array of regexp patterns that are matched against all source file paths before re-running tests in watch mode
+  // watchPathIgnorePatterns: [],
+
+  // Whether to use watchman for file crawling
+  // watchman: true,
+};

extensions/ql-vscode/media/dark/github.svg

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extensions/ql-vscode/media/dark/sort-num.svg

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extensions/ql-vscode/media/drive.svg

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+</svg>

extensions/ql-vscode/media/globe.svg

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+<circle cx="7.5" cy="7.5" r="7" stroke="#959DA5"/>
+<mask id="mask0_394_2982" style="mask-type:alpha" maskUnits="userSpaceOnUse" x="0" y="0" width="15" height="15">
+<circle cx="7.5" cy="7.5" r="7.5" fill="#C4C4C4"/>
+</mask>
+<g mask="url(#mask0_394_2982)">
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+<line y1="7.5" x2="15" y2="7.5" stroke="#959DA5"/>
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extensions/ql-vscode/media/light/github.svg

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+<g clip-path="url(#clip0)">
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+</defs>
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+	</g>
+</g>
+</svg>

extensions/ql-vscode/media/logo.svg

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-</svg>
+<svg width="16" height="16" viewBox="0 0 16 16" fill="none" xmlns="http://www.w3.org/2000/svg">
+<path d="M8.19789 8C8.19789 8.51894 8.1155 8.97538 7.95073 9.36932C7.78595 9.76326 7.56152 10.0871 7.27743 10.3409L8.10982 11.3864H6.96209L6.49334 10.8097C6.17705 10.929 5.83709 10.9886 5.47346 10.9886C4.95641 10.9886 4.4924 10.8712 4.08141 10.6364C3.67042 10.4015 3.34562 10.0611 3.10698 9.61506C2.86834 9.16903 2.74902 8.63068 2.74902 8C2.74902 7.36553 2.86834 6.82576 3.10698 6.38068C3.34562 5.9356 3.67042 5.59612 4.08141 5.36222C4.4924 5.12831 4.95641 5.01136 5.47346 5.01136C5.98861 5.01136 6.45167 5.12831 6.86266 5.36222C7.27365 5.59612 7.59893 5.9356 7.83851 6.38068C8.0781 6.82576 8.19789 7.36553 8.19789 8ZM5.04732 8.88636H6.09277L6.52459 9.44034C6.65906 9.27936 6.7637 9.0786 6.83851 8.83807C6.91332 8.59754 6.95073 8.31818 6.95073 8C6.95073 7.38257 6.81626 6.91146 6.54732 6.58665C6.27838 6.26184 5.92043 6.09943 5.47346 6.09943C5.02648 6.09943 4.66853 6.26184 4.39959 6.58665C4.13065 6.91146 3.99618 7.38257 3.99618 8C3.99618 8.61553 4.13065 9.08617 4.39959 9.41193C4.66853 9.73769 5.02648 9.90057 5.47346 9.90057C5.5852 9.90057 5.69126 9.89015 5.79164 9.86932L5.04732 8.88636ZM9.52695 11V5H10.7571V9.9858H13.2514V11H9.52695Z" fill="#24292F"/>
+<path fill-rule="evenodd" clip-rule="evenodd" d="M13 1.5H3C2.17157 1.5 1.5 2.17157 1.5 3V13C1.5 13.8284 2.17157 14.5 3 14.5H13C13.8284 14.5 14.5 13.8284 14.5 13V3C14.5 2.17157 13.8284 1.5 13 1.5ZM3 0C1.34315 0 0 1.34315 0 3V13C0 14.6569 1.34315 16 3 16H13C14.6569 16 16 14.6569 16 13V3C16 1.34315 14.6569 0 13 0H3Z" fill="#24292F"/>
+</svg>

extensions/ql-vscode/scripts/forbid-mocha-only

@@ -0,0 +1,6 @@
+if grep -rq --include '*.test.ts' 'it.only\|describe.only' './test' './src'; then
+    echo 'There is a .only() in the tests. Please remove it.'
+    exit 1;
+else
+    exit 0;
+fi

extensions/ql-vscode/snippets.json

@@ -0,0 +1,134 @@
+{
+  "Query Metadata": {
+    "prefix": "querymetadata",
+    "body": [
+      "/**",
+      " * @name $1",
+      " * @description $2",
+      " * @kind $3",
+      " * @id $4",
+      " * @tags $5",
+      " */"
+    ],
+    "description": "Metadata for a query"
+  },
+  "Class": {
+    "prefix": "class",
+    "body": ["class $1 extends $2 {", "\t$0", "}"],
+    "description": "A class"
+  },
+  "From/Where/Select": {
+    "prefix": "from",
+    "body": ["from $1", "where $2", "select $3"],
+    "description": "A from/where/select statement"
+  },
+  "Predicate": {
+    "prefix": "predicate",
+    "body": ["predicate $1($2) {", "\t$0", "}"],
+    "description": "A predicate"
+  },
+  "Dataflow Tracking Class": {
+    "prefix": "dataflowtracking",
+    "body": [
+      "class $1 extends DataFlow::Configuration {",
+      "\t$1() { this = \"$1\" }",
+      "\t",
+      "\toverride predicate isSource(DataFlow::Node node) {",
+      "\t\t${2:none()}",
+      "\t}",
+      "\t",
+      "\toverride predicate isSink(DataFlow::Node node) {",
+      "\t\t${3:none()}",
+      "\t}",
+      "}"
+    ],
+    "description": "Boilerplate for a dataflow tracking class"
+  },
+  "Taint Tracking Class": {
+    "prefix": "tainttracking",
+    "body": [
+      "class $1 extends TaintTracking::Configuration {",
+      "\t$1() { this = \"$1\" }",
+      "\t",
+      "\toverride predicate isSource(DataFlow::Node node) {",
+      "\t\t${2:none()}",
+      "\t}",
+      "\t",
+      "\toverride predicate isSink(DataFlow::Node node) {",
+      "\t\t${3:none()}",
+      "\t}",
+      "}"
+    ],
+    "description": "Boilerplate for a taint tracking class"
+  },
+  "Count": {
+    "prefix": "count",
+    "body": ["count($1 | $2 | $3)"],
+    "description": "A count aggregate"
+  },
+  "Max": {
+    "prefix": "max",
+    "body": ["max($1 | $2 | $3)"],
+    "description": "A max aggregate"
+  },
+  "Min": {
+    "prefix": "min",
+    "body": ["min($1 | $2 | $3)"],
+    "description": "A min aggregate"
+  },
+  "Average": {
+    "prefix": "avg",
+    "body": ["avg($1 | $2 | $3)"],
+    "description": "An average aggregate"
+  },
+  "Sum": {
+    "prefix": "sum",
+    "body": ["sum($1 | $2 | $3)"],
+    "description": "A sum aggregate"
+  },
+  "Concatenation": {
+    "prefix": "concat",
+    "body": ["concat($1 | $2 | $3)"],
+    "description": "A concatenation aggregate"
+  },
+  "Rank": {
+    "prefix": "rank",
+    "body": ["rank[$1]($2 | $3 | $4)"],
+    "description": "A rank aggregate"
+  },
+  "Strict Sum": {
+    "prefix": "strictsum",
+    "body": ["strictsum($1 | $2 | $3)"],
+    "description": "A strict sum aggregate"
+  },
+  "Strict Concatenation": {
+    "prefix": "strictconcat",
+    "body": ["strictconcat($1 | $2 | $3)"],
+    "description": "A strict concatenation aggregate"
+  },
+  "Strict Count": {
+    "prefix": "strictcount",
+    "body": ["strictcount($1 | $2 | $3)"],
+    "description": "A strict count aggregate"
+  },
+  "Unique": {
+    "prefix": "unique",
+    "body": ["unique($1 | $2 | $3)"],
+    "description": "A unique aggregate"
+  },
+  "Exists": {
+    "prefix": "exists",
+    "body": ["exists($1 | $2 | $3)"],
+    "description": "An exists quantifier"
+  },
+  "For All": {
+    "prefix": "forall",
+    "body": ["forall($1 | $2 | $3)"],
+    "description": "A for all quantifier"
+  },
+  "For All and Exists": {
+    "prefix": "forex",
+    "body": ["forex($1 | $2 | $3)"],
+    "description": "A for all and exists quantifier"
+  }
+}

extensions/ql-vscode/src/abstract-webview.ts

@@ -0,0 +1,129 @@
+import {
+  WebviewPanel,
+  ExtensionContext,
+  window as Window,
+  ViewColumn,
+  Uri,
+  WebviewPanelOptions,
+  WebviewOptions
+} from 'vscode';
+import * as path from 'path';
+
+import { DisposableObject } from './pure/disposable-object';
+import { tmpDir } from './helpers';
+import { getHtmlForWebview, WebviewMessage, WebviewView } from './interface-utils';
+
+export type WebviewPanelConfig = {
+  viewId: string;
+  title: string;
+  viewColumn: ViewColumn;
+  view: WebviewView;
+  preserveFocus?: boolean;
+  additionalOptions?: WebviewPanelOptions & WebviewOptions;
+}
+
+export abstract class AbstractWebview<ToMessage extends WebviewMessage, FromMessage extends WebviewMessage> extends DisposableObject {
+  protected panel: WebviewPanel | undefined;
+  protected panelLoaded = false;
+  protected panelLoadedCallBacks: (() => void)[] = [];
+
+  constructor(
+    protected readonly ctx: ExtensionContext
+  ) {
+    super();
+  }
+
+  public async restoreView(panel: WebviewPanel): Promise<void> {
+    this.panel = panel;
+    this.setupPanel(panel);
+  }
+
+  protected get isShowingPanel() {
+    return !!this.panel;
+  }
+
+  protected getPanel(): WebviewPanel {
+    if (this.panel == undefined) {
+      const { ctx } = this;
+
+      const config = this.getPanelConfig();
+
+      this.panel = Window.createWebviewPanel(
+        config.viewId,
+        config.title,
+        { viewColumn: config.viewColumn, preserveFocus: config.preserveFocus },
+        {
+          enableScripts: true,
+          enableFindWidget: true,
+          retainContextWhenHidden: true,
+          ...config.additionalOptions,
+          localResourceRoots: [
+            ...(config.additionalOptions?.localResourceRoots ?? []),
+            Uri.file(tmpDir.name),
+            Uri.file(path.join(ctx.extensionPath, 'out'))
+          ],
+        }
+      );
+      this.setupPanel(this.panel);
+    }
+    return this.panel;
+  }
+
+  protected setupPanel(panel: WebviewPanel): void {
+    const config = this.getPanelConfig();
+
+    this.push(
+      panel.onDidDispose(
+        () => {
+          this.panel = undefined;
+          this.panelLoaded = false;
+          this.onPanelDispose();
+        },
+        null,
+        this.ctx.subscriptions
+      )
+    );
+
+    panel.webview.html = getHtmlForWebview(
+      this.ctx,
+      panel.webview,
+      config.view,
+      {
+        allowInlineStyles: true,
+      }
+    );
+    this.push(
+      panel.webview.onDidReceiveMessage(
+        async (e) => this.onMessage(e),
+        undefined,
+        this.ctx.subscriptions
+      )
+    );
+  }
+
+  protected abstract getPanelConfig(): WebviewPanelConfig;
+
+  protected abstract onPanelDispose(): void;
+
+  protected abstract onMessage(msg: FromMessage): Promise<void>;
+
+  protected waitForPanelLoaded(): Promise<void> {
+    return new Promise((resolve) => {
+      if (this.panelLoaded) {
+        resolve();
+      } else {
+        this.panelLoadedCallBacks.push(resolve);
+      }
+    });
+  }
+
+  protected onWebViewLoaded(): void {
+    this.panelLoaded = true;
+    this.panelLoadedCallBacks.forEach((cb) => cb());
+    this.panelLoadedCallBacks = [];
+  }
+
+  protected postMessage(msg: ToMessage): Thenable<boolean> {
+    return this.getPanel().webview.postMessage(msg);
+  }
+}

extensions/ql-vscode/src/additional-typings.d.ts

@@ -0,0 +1,15 @@
+/**
+ * The d3 library is designed to work in both the browser and
+ * node. Consequently their typings files refer to both node
+ * types like `Buffer` (which don't exist in the browser), and browser
+ * types like `Blob` (which don't exist in node). Instead of sticking
+ * all of `dom` in `compilerOptions.lib`, it suffices just to put in a
+ * stub definition of the affected types so that compilation
+ * succeeds.
+ */
+
+declare type RequestInit = Record<string, unknown>;
+declare type ElementTagNameMap = any;
+declare type NodeListOf<T> = Record<string, T>;
+declare type Node = Record<string, unknown>;
+declare type XMLDocument = Record<string, unknown>;

extensions/ql-vscode/src/archive-filesystem-provider.ts

@@ -115,7 +115,7 @@ class InvalidSourceArchiveUriError extends Error {
 export function decodeSourceArchiveUri(uri: vscode.Uri): ZipFileReference {
   if (!uri.authority) {
     // Uri is malformed, but this is recoverable
-    logger.log(`Warning: ${new InvalidSourceArchiveUriError(uri).message}`);
+    void logger.log(`Warning: ${new InvalidSourceArchiveUriError(uri).message}`);
     return {
       pathWithinSourceArchive: '/',
       sourceArchiveZipPath: uri.path
@@ -141,7 +141,7 @@ function ensureFile(map: DirectoryHierarchyMap, file: string) {
   const dirname = path.dirname(file);
   if (dirname === '.') {
     const error = `Ill-formed path ${file} in zip archive (expected absolute path)`;
-    logger.log(error);
+    void logger.log(error);
     throw new Error(error);
   }
   ensureDir(map, dirname);
@@ -167,21 +167,26 @@ type Archive = {
   dirMap: DirectoryHierarchyMap;
 };
 
+async function parse_zip(zipPath: string): Promise<Archive> {
+  if (!await fs.pathExists(zipPath))
+    throw vscode.FileSystemError.FileNotFound(zipPath);
+  const archive: Archive = { unzipped: await unzipper.Open.file(zipPath), dirMap: new Map };
+  archive.unzipped.files.forEach(f => { ensureFile(archive.dirMap, path.resolve('/', f.path)); });
+  return archive;
+}
+
 export class ArchiveFileSystemProvider implements vscode.FileSystemProvider {
   private readOnlyError = vscode.FileSystemError.NoPermissions('write operation attempted, but source archive filesystem is readonly');
-  private archives: Map<string, Archive> = new Map;
+  private archives: Map<string, Promise<Archive>> = new Map;
 
   private async getArchive(zipPath: string): Promise<Archive> {
     if (!this.archives.has(zipPath)) {
-      if (!await fs.pathExists(zipPath))
-        throw vscode.FileSystemError.FileNotFound(zipPath);
-      const archive: Archive = { unzipped: await unzipper.Open.file(zipPath), dirMap: new Map };
-      archive.unzipped.files.forEach(f => { ensureFile(archive.dirMap, path.resolve('/', f.path)); });
-      this.archives.set(zipPath, archive);
+      this.archives.set(zipPath, parse_zip(zipPath));
     }
-    return this.archives.get(zipPath)!;
+    return await this.archives.get(zipPath)!;
   }
 
+
   root = new Directory('');
 
   // metadata

extensions/ql-vscode/src/astViewer.ts

@@ -10,7 +10,8 @@ import {
   TextEditorSelectionChangeEvent,
   TextEditorSelectionChangeKind,
   Location,
-  Range
+  Range,
+  Uri
 } from 'vscode';
 import * as path from 'path';
 
@@ -18,8 +19,9 @@ import { DatabaseItem } from './databases';
 import { UrlValue, BqrsId } from './pure/bqrs-cli-types';
 import { showLocation } from './interface-utils';
 import { isStringLoc, isWholeFileLoc, isLineColumnLoc } from './pure/bqrs-utils';
-import { commandRunner } from './helpers';
-import { DisposableObject } from './vscode-utils/disposable-object';
+import { commandRunner } from './commandRunner';
+import { DisposableObject } from './pure/disposable-object';
+import { showAndLogErrorMessage } from './helpers';
 
 export interface AstItem {
   id: BqrsId;
@@ -40,7 +42,7 @@ class AstViewerDataProvider extends DisposableObject implements TreeDataProvider
   public db: DatabaseItem | undefined;
 
   private _onDidChangeTreeData =
-    new EventEmitter<AstItem | undefined>();
+    this.push(new EventEmitter<AstItem | undefined>());
   readonly onDidChangeTreeData: Event<AstItem | undefined> =
     this._onDidChangeTreeData.event;
 
@@ -55,7 +57,7 @@ class AstViewerDataProvider extends DisposableObject implements TreeDataProvider
   }
 
   refresh(): void {
-    this._onDidChangeTreeData.fire();
+    this._onDidChangeTreeData.fire(undefined);
   }
   getChildren(item?: AstItem): ProviderResult<AstItem[]> {
     const children = item ? item.children : this.roots;
@@ -103,7 +105,7 @@ class AstViewerDataProvider extends DisposableObject implements TreeDataProvider
 export class AstViewer extends DisposableObject {
   private treeView: TreeView<AstItem>;
   private treeDataProvider: AstViewerDataProvider;
-  private currentFile: string | undefined;
+  private currentFileUri: Uri | undefined;
 
   constructor() {
     super();
@@ -124,13 +126,18 @@ export class AstViewer extends DisposableObject {
     this.push(window.onDidChangeTextEditorSelection(this.updateTreeSelection, this));
   }
 
-  updateRoots(roots: AstItem[], db: DatabaseItem, fileName: string) {
+  updateRoots(roots: AstItem[], db: DatabaseItem, fileUri: Uri) {
     this.treeDataProvider.roots = roots;
     this.treeDataProvider.db = db;
     this.treeDataProvider.refresh();
-    this.treeView.message = `AST for ${path.basename(fileName)}`;
-    this.treeView.reveal(roots[0], { focus: false });
-    this.currentFile = fileName;
+    this.treeView.message = `AST for ${path.basename(fileUri.fsPath)}`;
+    this.currentFileUri = fileUri;
+    // Handle error on reveal. This could happen if
+    // the tree view is disposed during the reveal.
+    this.treeView.reveal(roots[0], { focus: false })?.then(
+      () => { /**/ },
+      err => showAndLogErrorMessage(err)
+    );
   }
 
   private updateTreeSelection(e: TextEditorSelectionChangeEvent) {
@@ -168,7 +175,7 @@ export class AstViewer extends DisposableObject {
 
     if (
       this.treeView.visible &&
-      e.textEditor.document.uri.fsPath === this.currentFile &&
+      e.textEditor.document.uri.fsPath === this.currentFileUri?.fsPath &&
       e.selections.length === 1
     ) {
       const selection = e.selections[0];
@@ -178,7 +185,12 @@ export class AstViewer extends DisposableObject {
 
       const targetItem = findBest(range, this.treeDataProvider.roots);
       if (targetItem) {
-        this.treeView.reveal(targetItem);
+        // Handle error on reveal. This could happen if
+        // the tree view is disposed during the reveal.
+        this.treeView.reveal(targetItem)?.then(
+          () => { /**/ },
+          err => showAndLogErrorMessage(err)
+        );
       }
     }
   }
@@ -188,6 +200,6 @@ export class AstViewer extends DisposableObject {
     this.treeDataProvider.db = undefined;
     this.treeDataProvider.refresh();
     this.treeView.message = undefined;
-    this.currentFile = undefined;
+    this.currentFileUri = undefined;
   }
 }

extensions/ql-vscode/src/authentication.ts

@@ -0,0 +1,103 @@
+import * as vscode from 'vscode';
+import * as Octokit from '@octokit/rest';
+import { retry } from '@octokit/plugin-retry';
+
+const GITHUB_AUTH_PROVIDER_ID = 'github';
+
+// We need 'repo' scope for triggering workflows and 'gist' scope for exporting results to Gist.
+// For a comprehensive list of scopes, see:
+// https://docs.github.com/apps/building-oauth-apps/understanding-scopes-for-oauth-apps
+const SCOPES = ['repo', 'gist'];
+
+/**
+ * Handles authentication to GitHub, using the VS Code [authentication API](https://code.visualstudio.com/api/references/vscode-api#authentication).
+ */
+export class Credentials {
+  private octokit: Octokit.Octokit | undefined;
+
+  // Explicitly make the constructor private, so that we can't accidentally call the constructor from outside the class
+  // without also initializing the class.
+  // eslint-disable-next-line @typescript-eslint/no-empty-function
+  private constructor() { }
+
+  /**
+   * Initializes an instance of credentials with an octokit instance.
+   *
+   * Do not call this method until you know you actually need an instance of credentials.
+   * since calling this method will require the user to log in.
+   *
+   * @param context The extension context.
+   * @returns An instance of credentials.
+   */
+  static async initialize(context: vscode.ExtensionContext): Promise<Credentials> {
+    const c = new Credentials();
+    c.registerListeners(context);
+    c.octokit = await c.createOctokit(false);
+    return c;
+  }
+
+  /**
+   * Initializes an instance of credentials with an octokit instance using
+   * a token from the user's GitHub account. This method is meant to be
+   * used non-interactive environments such as tests.
+   *
+   * @param overrideToken The GitHub token to use for authentication.
+   * @returns An instance of credentials.
+   */
+  static async initializeWithToken(overrideToken: string) {
+    const c = new Credentials();
+    c.octokit = await c.createOctokit(false, overrideToken);
+    return c;
+  }
+
+  private async createOctokit(createIfNone: boolean, overrideToken?: string): Promise<Octokit.Octokit | undefined> {
+    if (overrideToken) {
+      return new Octokit.Octokit({ auth: overrideToken, retry });
+    }
+
+    const session = await vscode.authentication.getSession(GITHUB_AUTH_PROVIDER_ID, SCOPES, { createIfNone });
+
+    if (session) {
+      return new Octokit.Octokit({
+        auth: session.accessToken,
+        retry
+      });
+    } else {
+      return undefined;
+    }
+  }
+
+  registerListeners(context: vscode.ExtensionContext): void {
+    // Sessions are changed when a user logs in or logs out.
+    context.subscriptions.push(vscode.authentication.onDidChangeSessions(async e => {
+      if (e.provider.id === GITHUB_AUTH_PROVIDER_ID) {
+        this.octokit = await this.createOctokit(false);
+      }
+    }));
+  }
+
+  /**
+   * Creates or returns an instance of Octokit.
+   *
+   * @param requireAuthentication Whether the Octokit instance needs to be authenticated as user.
+   * @returns An instance of Octokit.
+   */
+  async getOctokit(requireAuthentication = true): Promise<Octokit.Octokit> {
+    if (this.octokit) {
+      return this.octokit;
+    }
+
+    this.octokit = await this.createOctokit(requireAuthentication);
+
+    if (!this.octokit) {
+      if (requireAuthentication) {
+        throw new Error('Did not initialize Octokit.');
+      }
+
+      // We don't want to set this in this.octokit because that would prevent
+      // authenticating when requireCredentials is true.
+      return new Octokit.Octokit({ retry });
+    }
+    return this.octokit;
+  }
+}

extensions/ql-vscode/src/blob.d.ts

@@ -1,11 +0,0 @@
-/**
- * The npm library jszip is designed to work in both the browser and
- * node. Consequently its typings @types/jszip refers to both node
- * types like `Buffer` (which don't exist in the browser), and browser
- * types like `Blob` (which don't exist in node). Instead of sticking
- * all of `dom` in `compilerOptions.lib`, it suffices just to put in a
- * stub definition of the type `Blob` here so that compilation
- * succeeds.
- */
-
-declare type Blob = string;

extensions/ql-vscode/src/cli-version.ts

@@ -1,6 +1,7 @@
 import * as semver from 'semver';
 import { runCodeQlCliCommand } from './cli';
 import { Logger } from './logging';
+import { getErrorMessage } from './pure/helpers-pure';
 
 /**
  * Get the version of a CodeQL CLI.
@@ -18,7 +19,7 @@ export async function getCodeQlCliVersion(codeQlPath: string, logger: Logger): P
   } catch (e) {
     // Failed to run the version command. This might happen if the cli version is _really_ old, or it is corrupted.
     // Either way, we can't determine compatibility.
-    logger.log(`Failed to run 'codeql version'. Reason: ${e.message}`);
+    void logger.log(`Failed to run 'codeql version'. Reason: ${getErrorMessage(e)}`);
     return undefined;
   }
 }

extensions/ql-vscode/src/cli.ts

@@ -1,4 +1,3 @@
-/* eslint-disable @typescript-eslint/camelcase */
 import * as cpp from 'child-process-promise';
 import * as child_process from 'child_process';
 import * as fs from 'fs-extra';
@@ -9,21 +8,28 @@ import { Readable } from 'stream';
 import { StringDecoder } from 'string_decoder';
 import * as tk from 'tree-kill';
 import { promisify } from 'util';
-import { CancellationToken, Disposable } from 'vscode';
+import { CancellationToken, commands, Disposable, Uri } from 'vscode';
 
 import { BQRSInfo, DecodedBqrsChunk } from './pure/bqrs-cli-types';
-import { CliConfig } from './config';
+import { allowCanaryQueryServer, CliConfig } from './config';
 import { DistributionProvider, FindDistributionResultKind } from './distribution';
-import { assertNever } from './pure/helpers-pure';
+import { assertNever, getErrorMessage, getErrorStack } from './pure/helpers-pure';
 import { QueryMetadata, SortDirection } from './pure/interface-types';
 import { Logger, ProgressReporter } from './logging';
-import { CompilationMessage } from './pure/messages';
+import { CompilationMessage } from './pure/legacy-messages';
+import { sarifParser } from './sarif-parser';
+import { dbSchemeToLanguage, walkDirectory } from './helpers';
 
 /**
  * The version of the SARIF format that we are using.
  */
 const SARIF_FORMAT = 'sarifv2.1.0';
 
+/**
+ * The string used to specify CSV format.
+ */
+const CSV_FORMAT = 'csv';
+
 /**
  * Flags to pass to all cli commands.
  */
@@ -39,6 +45,16 @@ export interface QuerySetup {
   compilationCache?: string;
 }
 
+/**
+ * The expected output of `codeql resolve queries --format bylanguage`.
+ */
+export interface QueryInfoByLanguage {
+  // Using `unknown` as a placeholder. For now, the value is only ever an empty object.
+  byLanguage: Record<string, Record<string, unknown>>;
+  noDeclaredLanguage: Record<string, unknown>;
+  multipleDeclaredLanguages: Record<string, unknown>;
+}
+
 /**
  * The expected output of `codeql resolve database`.
  */
@@ -50,6 +66,7 @@ export interface DbInfo {
   sourceArchiveRoot: string;
   datasetFolder: string;
   logsFolder: string;
+  languages: string[];
 }
 
 /**
@@ -58,6 +75,7 @@ export interface DbInfo {
 export interface UpgradesInfo {
   scripts: string[];
   finalDbscheme: string;
+  matchesTarget?: boolean;
 }
 
 /**
@@ -65,6 +83,25 @@ export interface UpgradesInfo {
  */
 export type QlpacksInfo = { [name: string]: string[] };
 
+/**
+ * The expected output of `codeql resolve languages`.
+ */
+export type LanguagesInfo = { [name: string]: string[] };
+
+/** Information about an ML model, as resolved by `codeql resolve ml-models`. */
+export type MlModelInfo = {
+  checksum: string;
+  path: string;
+};
+
+/** The expected output of `codeql resolve ml-models`. */
+export type MlModelsInfo = { models: MlModelInfo[] };
+
+/**
+ * The expected output of `codeql resolve qlref`.
+ */
+export type QlrefInfo = { resolvedPath: string };
+
 // `codeql bqrs interpret` requires both of these to be present or
 // both absent.
 export interface SourceInfo {
@@ -96,6 +133,8 @@ export interface TestCompleted {
   evaluationMs: number;
   expected: string;
   diff: string[] | undefined;
+  failureDescription?: string;
+  failureStage?: string;
 }
 
 /**
@@ -118,10 +157,6 @@ interface BqrsDecodeOptions {
  */
 export class CodeQLCliServer implements Disposable {
 
-  /**
-   * CLI version where --kind=DIL was introduced
-   */
-  private static CLI_VERSION_WITH_DECOMPILE_KIND_DIL = new SemVer('2.3.0');
 
   /** The process for the cli server, or undefined if one doesn't exist yet */
   process?: child_process.ChildProcessWithoutNullStreams;
@@ -133,15 +168,27 @@ export class CodeQLCliServer implements Disposable {
   nullBuffer: Buffer;
 
   /** Version of current cli, lazily computed by the `getVersion()` method */
-  _version: SemVer | undefined;
+  private _version: Promise<SemVer> | undefined;
+
+  /**
+   * The languages supported by the current version of the CLI, computed by `getSupportedLanguages()`.
+   */
+  private _supportedLanguages: string[] | undefined;
 
   /** Path to current codeQL executable, or undefined if not running yet. */
   codeQlPath: string | undefined;
 
+  cliConstraints = new CliVersionConstraint(this);
+
+  /**
+   * When set to true, ignore some modal popups and assume user has clicked "yes".
+   */
+  public quiet = false;
+
   constructor(
     private distributionProvider: DistributionProvider,
     private cliConfig: CliConfig,
-    private logger: Logger,
+    private logger: Logger
   ) {
     this.commandQueue = [];
     this.commandInProcess = false;
@@ -149,12 +196,15 @@ export class CodeQLCliServer implements Disposable {
     if (this.distributionProvider.onDidChangeDistribution) {
       this.distributionProvider.onDidChangeDistribution(() => {
         this.restartCliServer();
+        this._version = undefined;
+        this._supportedLanguages = undefined;
       });
     }
     if (this.cliConfig.onDidChangeConfiguration) {
       this.cliConfig.onDidChangeConfiguration(() => {
         this.restartCliServer();
         this._version = undefined;
+        this._supportedLanguages = undefined;
       });
     }
   }
@@ -166,15 +216,15 @@ export class CodeQLCliServer implements Disposable {
   killProcessIfRunning(): void {
     if (this.process) {
       // Tell the Java CLI server process to shut down.
-      this.logger.log('Sending shutdown request');
+      void this.logger.log('Sending shutdown request');
       try {
         this.process.stdin.write(JSON.stringify(['shutdown']), 'utf8');
         this.process.stdin.write(this.nullBuffer);
-        this.logger.log('Sent shutdown request');
+        void this.logger.log('Sent shutdown request');
       } catch (e) {
         // We are probably fine here, the process has already closed stdin.
-        this.logger.log(`Shutdown request failed: process stdin may have already closed. The error was ${e}`);
-        this.logger.log('Stopping the process anyway.');
+        void this.logger.log(`Shutdown request failed: process stdin may have already closed. The error was ${e}`);
+        void this.logger.log('Stopping the process anyway.');
       }
       // Close the stdin and stdout streams.
       // This is important on Windows where the child process may not die cleanly.
@@ -190,7 +240,7 @@ export class CodeQLCliServer implements Disposable {
   /**
    * Restart the server when the current command terminates
    */
-  private restartCliServer(): void {
+  restartCliServer(): void {
     const callback = (): void => {
       try {
         this.killProcessIfRunning();
@@ -225,11 +275,16 @@ export class CodeQLCliServer implements Disposable {
    */
   private async launchProcess(): Promise<child_process.ChildProcessWithoutNullStreams> {
     const codeQlPath = await this.getCodeQlPath();
+    const args = [];
+    if (shouldDebugCliServer()) {
+      args.push('-J=-agentlib:jdwp=transport=dt_socket,address=localhost:9012,server=n,suspend=y,quiet=y');
+    }
+
     return await spawnServer(
       codeQlPath,
       'CodeQL CLI Server',
       ['execute', 'cli-server'],
-      [],
+      args,
       this.logger,
       _data => { /**/ }
     );
@@ -254,9 +309,9 @@ export class CodeQLCliServer implements Disposable {
       // Compute the full args array
       const args = command.concat(LOGGING_FLAGS).concat(commandArgs);
       const argsString = args.join(' ');
-      this.logger.log(`${description} using CodeQL CLI: ${argsString}...`);
+      void this.logger.log(`${description} using CodeQL CLI: ${argsString}...`);
       try {
-        await new Promise((resolve, reject) => {
+        await new Promise<void>((resolve, reject) => {
           // Start listening to stdout
           process.stdout.addListener('data', (newData: Buffer) => {
             stdoutBuffers.push(newData);
@@ -281,7 +336,7 @@ export class CodeQLCliServer implements Disposable {
         const fullBuffer = Buffer.concat(stdoutBuffers);
         // Make sure we remove the terminator;
         const data = fullBuffer.toString('utf8', 0, fullBuffer.length - 1);
-        this.logger.log('CLI command succeeded.');
+        void this.logger.log('CLI command succeeded.');
         return data;
       } catch (err) {
         // Kill the process if it isn't already dead.
@@ -291,10 +346,10 @@ export class CodeQLCliServer implements Disposable {
           stderrBuffers.length == 0
             ? new Error(`${description} failed: ${err}`)
             : new Error(`${description} failed: ${Buffer.concat(stderrBuffers).toString('utf8')}`);
-        newError.stack += (err.stack || '');
+        newError.stack += getErrorStack(err);
         throw newError;
       } finally {
-        this.logger.log(Buffer.concat(stderrBuffers).toString('utf8'));
+        void this.logger.log(Buffer.concat(stderrBuffers).toString('utf8'));
         // Remove the listeners we set up.
         process.stdout.removeAllListeners('data');
         process.stderr.removeAllListeners('data');
@@ -349,12 +404,12 @@ export class CodeQLCliServer implements Disposable {
     try {
       if (cancellationToken !== undefined) {
         cancellationRegistration = cancellationToken.onCancellationRequested(_e => {
-          tk(child.pid);
+          tk(child.pid || 0);
         });
       }
       if (logger !== undefined) {
         // The human-readable output goes to stderr.
-        logStream(child.stderr!, logger);
+        void logStream(child.stderr!, logger);
       }
 
       for await (const event of await splitStreamAtSeparators(child.stdout!, ['\0'])) {
@@ -393,7 +448,7 @@ export class CodeQLCliServer implements Disposable {
       try {
         yield JSON.parse(event) as EventType;
       } catch (err) {
-        throw new Error(`Parsing output of ${description} failed: ${err.stderr || err}`);
+        throw new Error(`Parsing output of ${description} failed: ${(err as any).stderr || getErrorMessage(err)}`);
       }
     }
   }
@@ -435,17 +490,20 @@ export class CodeQLCliServer implements Disposable {
    * @param command The `codeql` command to be run, provided as an array of command/subcommand names.
    * @param commandArgs The arguments to pass to the `codeql` command.
    * @param description Description of the action being run, to be shown in log and error messages.
+   * @param addFormat Whether or not to add commandline arguments to specify the format as JSON.
    * @param progressReporter Used to output progress messages, e.g. to the status bar.
    * @returns The contents of the command's stdout, if the command succeeded.
    */
-  async runJsonCodeQlCliCommand<OutputType>(command: string[], commandArgs: string[], description: string, progressReporter?: ProgressReporter): Promise<OutputType> {
-    // Add format argument first, in case commandArgs contains positional parameters.
-    const args = ['--format', 'json'].concat(commandArgs);
+  async runJsonCodeQlCliCommand<OutputType>(command: string[], commandArgs: string[], description: string, addFormat = true, progressReporter?: ProgressReporter): Promise<OutputType> {
+    let args: string[] = [];
+    if (addFormat) // Add format argument first, in case commandArgs contains positional parameters.
+      args = args.concat(['--format', 'json']);
+    args = args.concat(commandArgs);
     const result = await this.runCodeQlCliCommand(command, args, description, progressReporter);
     try {
       return JSON.parse(result) as OutputType;
     } catch (err) {
-      throw new Error(`Parsing output of ${description} failed: ${err.stderr || err}`);
+      throw new Error(`Parsing output of ${description} failed: ${(err as any).stderr || getErrorMessage(err)}`);
     }
   }
 
@@ -457,12 +515,24 @@ export class CodeQLCliServer implements Disposable {
   async resolveLibraryPath(workspaces: string[], queryPath: string): Promise<QuerySetup> {
     const subcommandArgs = [
       '--query', queryPath,
-      '--additional-packs',
-      workspaces.join(path.delimiter)
+      ...this.getAdditionalPacksArg(workspaces)
     ];
     return await this.runJsonCodeQlCliCommand<QuerySetup>(['resolve', 'library-path'], subcommandArgs, 'Resolving library paths');
   }
 
+  /**
+   * Resolves the language for a query.
+   * @param queryUri The URI of the query
+   */
+  async resolveQueryByLanguage(workspaces: string[], queryUri: Uri): Promise<QueryInfoByLanguage> {
+    const subcommandArgs = [
+      '--format', 'bylanguage',
+      queryUri.fsPath,
+      ...this.getAdditionalPacksArg(workspaces)
+    ];
+    return JSON.parse(await this.runCodeQlCliCommand(['resolve', 'queries'], subcommandArgs, 'Resolving query by language'));
+  }
+
   /**
    * Finds all available QL tests in a given directory.
    * @param testPath Root of directory tree to search for tests.
@@ -479,6 +549,29 @@ export class CodeQLCliServer implements Disposable {
     );
   }
 
+  public async resolveQlref(qlref: string): Promise<QlrefInfo> {
+    const subcommandArgs = [
+      qlref
+    ];
+    return await this.runJsonCodeQlCliCommand<QlrefInfo>(
+      ['resolve', 'qlref'],
+      subcommandArgs,
+      'Resolving qlref',
+      false
+    );
+  }
+
+  /**
+   * Issues an internal clear-cache command to the cli server. This
+   * command is used to clear the qlpack cache of the server.
+   *
+   * This cache is generally cleared every 1s. This method is used
+   * to force an early clearing of the cache.
+   */
+  public async clearCache(): Promise<void> {
+    await this.runCodeQlCliCommand(['clear-cache'], [], 'Clearing qlpack cache');
+  }
+
   /**
    * Runs QL tests.
    * @param testPaths Full paths of the tests to run.
@@ -489,12 +582,12 @@ export class CodeQLCliServer implements Disposable {
     testPaths: string[], workspaces: string[], options: TestRunOptions
   ): AsyncGenerator<TestCompleted, void, unknown> {
 
-    const subcommandArgs = [
-      '--additional-packs', workspaces.join(path.delimiter),
+    const subcommandArgs = this.cliConfig.additionalTestArguments.concat([
+      ...this.getAdditionalPacksArg(workspaces),
       '--threads',
       this.cliConfig.numberTestThreads.toString(),
       ...testPaths
-    ];
+    ]);
 
     for await (const event of await this.runAsyncCodeQlCliCommand<TestCompleted>(['test', 'run'],
       subcommandArgs, 'Run CodeQL Tests', options.cancellationToken, options.logger)) {
@@ -510,6 +603,20 @@ export class CodeQLCliServer implements Disposable {
     return await this.runJsonCodeQlCliCommand<QueryMetadata>(['resolve', 'metadata'], [queryPath], 'Resolving query metadata');
   }
 
+  /** Resolves the ML models that should be available when evaluating a query. */
+  async resolveMlModels(additionalPacks: string[], queryPath: string): Promise<MlModelsInfo> {
+    const args = await this.cliConstraints.supportsPreciseResolveMlModels()
+      // use the dirname of the path so that we can handle query libraries
+      ? [...this.getAdditionalPacksArg(additionalPacks), path.dirname(queryPath)]
+      : this.getAdditionalPacksArg(additionalPacks);
+    return await this.runJsonCodeQlCliCommand<MlModelsInfo>(
+      ['resolve', 'ml-models'],
+      args,
+      'Resolving ML models',
+      false
+    );
+  }
+
   /**
    * Gets the RAM setting for the query server.
    * @param queryMemoryMb The maximum amount of RAM to use, in MB.
@@ -523,7 +630,7 @@ export class CodeQLCliServer implements Disposable {
     if (queryMemoryMb !== undefined) {
       args.push('--ram', queryMemoryMb.toString());
     }
-    return await this.runJsonCodeQlCliCommand<string[]>(['resolve', 'ram'], args, 'Resolving RAM settings', progressReporter);
+    return await this.runJsonCodeQlCliCommand<string[]>(['resolve', 'ram'], args, 'Resolving RAM settings', true, progressReporter);
   }
   /**
    * Gets the headers (and optionally pagination info) of a bqrs.
@@ -539,6 +646,67 @@ export class CodeQLCliServer implements Disposable {
     return await this.runJsonCodeQlCliCommand<BQRSInfo>(['bqrs', 'info'], subcommandArgs, 'Reading bqrs header');
   }
 
+  async databaseUnbundle(archivePath: string, target: string, name?: string): Promise<string> {
+    const subcommandArgs = [];
+    if (target) subcommandArgs.push('--target', target);
+    if (name) subcommandArgs.push('--name', name);
+    subcommandArgs.push(archivePath);
+
+    return await this.runCodeQlCliCommand(['database', 'unbundle'], subcommandArgs, `Extracting ${archivePath} to directory ${target}`);
+  }
+
+  /**
+   * Uses a .qhelp file to generate Query Help documentation in a specified format.
+   * @param pathToQhelp The path to the .qhelp file
+   * @param format The format in which the query help should be generated {@link https://codeql.github.com/docs/codeql-cli/manual/generate-query-help/#cmdoption-codeql-generate-query-help-format}
+   * @param outputDirectory The output directory for the generated file
+   */
+  async generateQueryHelp(pathToQhelp: string, outputDirectory?: string): Promise<string> {
+    const subcommandArgs = ['--format=markdown'];
+    if (outputDirectory) subcommandArgs.push('--output', outputDirectory);
+    subcommandArgs.push(pathToQhelp);
+
+    return await this.runCodeQlCliCommand(['generate', 'query-help'], subcommandArgs, `Generating qhelp in markdown format at ${outputDirectory}`);
+  }
+
+  /**
+  * Generate a summary of an evaluation log.
+  * @param endSummaryPath The path to write only the end of query part of the human-readable summary to.
+  * @param inputPath The path of an evaluation event log.
+  * @param outputPath The path to write a human-readable summary of it to.
+  */
+  async generateLogSummary(
+    inputPath: string,
+    outputPath: string,
+    endSummaryPath: string,
+  ): Promise<string> {
+    const subcommandArgs = [
+      '--format=text',
+      `--end-summary=${endSummaryPath}`,
+      ...(await this.cliConstraints.supportsSourceMap() ? ['--sourcemap'] : []),
+      inputPath,
+      outputPath
+    ];
+    return await this.runCodeQlCliCommand(['generate', 'log-summary'], subcommandArgs, 'Generating log summary');
+  }
+
+  /**
+  * Generate a JSON summary of an evaluation log.
+  * @param inputPath The path of an evaluation event log.
+  * @param outputPath The path to write a JSON summary of it to.
+  */
+  async generateJsonLogSummary(
+    inputPath: string,
+    outputPath: string,
+  ): Promise<string> {
+    const subcommandArgs = [
+      '--format=predicates',
+      inputPath,
+      outputPath
+    ];
+    return await this.runCodeQlCliCommand(['generate', 'log-summary'], subcommandArgs, 'Generating JSON log summary');
+  }
+
   /**
   * Gets the results from a bqrs.
   * @param bqrsPath The path to the bqrs.
@@ -562,40 +730,76 @@ export class CodeQLCliServer implements Disposable {
     return await this.runJsonCodeQlCliCommand<DecodedBqrsChunk>(['bqrs', 'decode'], subcommandArgs, 'Reading bqrs data');
   }
 
-  async interpretBqrs(metadata: { kind: string; id: string }, resultsPath: string, interpretedResultsPath: string, sourceInfo?: SourceInfo): Promise<sarif.Log> {
+  async runInterpretCommand(format: string, additonalArgs: string[], metadata: QueryMetadata, resultsPath: string, interpretedResultsPath: string, sourceInfo?: SourceInfo) {
     const args = [
-      `-t=kind=${metadata.kind}`,
-      `-t=id=${metadata.id}`,
       '--output', interpretedResultsPath,
-      '--format', SARIF_FORMAT,
-      // TODO: This flag means that we don't group interpreted results
-      // by primary location. We may want to revisit whether we call
-      // interpretation with and without this flag, or do some
-      // grouping client-side.
-      '--no-group-results',
-    ];
+      '--format', format,
+      // Forward all of the query metadata.
+      ...Object.entries(metadata).map(([key, value]) => `-t=${key}=${value}`)
+    ].concat(additonalArgs);
     if (sourceInfo !== undefined) {
       args.push(
         '--source-archive', sourceInfo.sourceArchive,
         '--source-location-prefix', sourceInfo.sourceLocationPrefix
       );
     }
+
+    args.push(
+      '--threads',
+      this.cliConfig.numberThreads.toString(),
+    );
+
+    args.push(
+      '--max-paths',
+      this.cliConfig.maxPaths.toString(),
+    );
+
     args.push(resultsPath);
     await this.runCodeQlCliCommand(['bqrs', 'interpret'], args, 'Interpreting query results');
+  }
 
-    let output: string;
-    try {
-      output = await fs.readFile(interpretedResultsPath, 'utf8');
-    } catch (err) {
-      throw new Error(`Reading output of interpretation failed: ${err.stderr || err}`);
+  async interpretBqrsSarif(metadata: QueryMetadata, resultsPath: string, interpretedResultsPath: string, sourceInfo?: SourceInfo): Promise<sarif.Log> {
+    const additionalArgs = [
+      // TODO: This flag means that we don't group interpreted results
+      // by primary location. We may want to revisit whether we call
+      // interpretation with and without this flag, or do some
+      // grouping client-side.
+      '--no-group-results'
+    ];
+
+    await this.runInterpretCommand(SARIF_FORMAT, additionalArgs, metadata, resultsPath, interpretedResultsPath, sourceInfo);
+    return await sarifParser(interpretedResultsPath);
+  }
+
+  // Warning: this function is untenable for large dot files,
+  async readDotFiles(dir: string): Promise<string[]> {
+    const dotFiles: Promise<string>[] = [];
+    for await (const file of walkDirectory(dir)) {
+      if (file.endsWith('.dot')) {
+        dotFiles.push(fs.readFile(file, 'utf8'));
+      }
     }
+    return Promise.all(dotFiles);
+  }
+
+  async interpretBqrsGraph(metadata: QueryMetadata, resultsPath: string, interpretedResultsPath: string, sourceInfo?: SourceInfo): Promise<string[]> {
+    const additionalArgs = sourceInfo
+      ? ['--dot-location-url-format', 'file://' + sourceInfo.sourceLocationPrefix + '{path}:{start:line}:{start:column}:{end:line}:{end:column}']
+      : [];
+
+    await this.runInterpretCommand('dot', additionalArgs, metadata, resultsPath, interpretedResultsPath, sourceInfo);
+
     try {
-      return JSON.parse(output) as sarif.Log;
+      const dot = await this.readDotFiles(interpretedResultsPath);
+      return dot;
     } catch (err) {
-      throw new Error(`Parsing output of interpretation failed: ${err.stderr || err}`);
+      throw new Error(`Reading output of interpretation failed: ${getErrorMessage(err)}`);
     }
   }
 
+  async generateResultsCsv(metadata: QueryMetadata, resultsPath: string, csvPath: string, sourceInfo?: SourceInfo): Promise<void> {
+    await this.runInterpretCommand(CSV_FORMAT, [], metadata, resultsPath, csvPath, sourceInfo);
+  }
 
   async sortBqrs(resultsPath: string, sortedResultsPath: string, resultSet: string, sortKeys: number[], sortDirections: SortDirection[]): Promise<void> {
     const sortDirectionStrings = sortDirections.map(direction => {
@@ -635,12 +839,19 @@ export class CodeQLCliServer implements Disposable {
    * Gets information necessary for upgrading a database.
    * @param dbScheme the path to the dbscheme of the database to be upgraded.
    * @param searchPath A list of directories to search for upgrade scripts.
+   * @param allowDowngradesIfPossible Whether we should try and include downgrades of we can.
+   * @param targetDbScheme The dbscheme to try to upgrade to.
    * @returns A list of database upgrade script directories
    */
-  resolveUpgrades(dbScheme: string, searchPath: string[]): Promise<UpgradesInfo> {
-    const args = ['--additional-packs', searchPath.join(path.delimiter), '--dbscheme', dbScheme];
-
-    return this.runJsonCodeQlCliCommand<UpgradesInfo>(
+  async resolveUpgrades(dbScheme: string, searchPath: string[], allowDowngradesIfPossible: boolean, targetDbScheme?: string): Promise<UpgradesInfo> {
+    const args = [...this.getAdditionalPacksArg(searchPath), '--dbscheme', dbScheme];
+    if (targetDbScheme) {
+      args.push('--target-dbscheme', targetDbScheme);
+      if (allowDowngradesIfPossible && await this.cliConstraints.supportsDowngrades()) {
+        args.push('--allow-downgrades');
+      }
+    }
+    return await this.runJsonCodeQlCliCommand<UpgradesInfo>(
       ['resolve', 'upgrades'],
       args,
       'Resolving database upgrade scripts',
@@ -655,7 +866,7 @@ export class CodeQLCliServer implements Disposable {
    * @returns A dictionary mapping qlpack name to the directory it comes from
    */
   resolveQlpacks(additionalPacks: string[], searchPath?: string[]): Promise<QlpacksInfo> {
-    const args = ['--additional-packs', additionalPacks.join(path.delimiter)];
+    const args = this.getAdditionalPacksArg(additionalPacks);
     if (searchPath?.length) {
       args.push('--search-path', path.join(...searchPath));
     }
@@ -667,6 +878,31 @@ export class CodeQLCliServer implements Disposable {
     );
   }
 
+  /**
+   * Gets information about the available languages.
+   * @returns A dictionary mapping language name to the directory it comes from
+   */
+  async resolveLanguages(): Promise<LanguagesInfo> {
+    return await this.runJsonCodeQlCliCommand<LanguagesInfo>(['resolve', 'languages'], [], 'Resolving languages');
+  }
+
+  /**
+   * Gets the list of available languages. Refines the result of `resolveLanguages()`, by excluding
+   * extra things like "xml" and "properties".
+   *
+   * @returns An array of languages that are supported by the current version of the CodeQL CLI.
+   */
+  public async getSupportedLanguages(): Promise<string[]> {
+    if (!this._supportedLanguages) {
+      // Get the intersection of resolveLanguages with the list of hardcoded languages in dbSchemeToLanguage.
+      const resolvedLanguages = Object.keys(await this.resolveLanguages());
+      const hardcodedLanguages = Object.values(dbSchemeToLanguage);
+
+      this._supportedLanguages = resolvedLanguages.filter(lang => hardcodedLanguages.includes(lang));
+    }
+    return this._supportedLanguages;
+  }
+
   /**
    * Gets information about queries in a query suite.
    * @param suite The suite to resolve.
@@ -675,11 +911,15 @@ export class CodeQLCliServer implements Disposable {
    *   the default CLI search path is used.
    * @returns A list of query files found.
    */
-  resolveQueriesInSuite(suite: string, additionalPacks: string[], searchPath?: string[]): Promise<string[]> {
-    const args = ['--additional-packs', additionalPacks.join(path.delimiter)];
+  async resolveQueriesInSuite(suite: string, additionalPacks: string[], searchPath?: string[]): Promise<string[]> {
+    const args = this.getAdditionalPacksArg(additionalPacks);
     if (searchPath !== undefined) {
       args.push('--search-path', path.join(...searchPath));
     }
+    if (await this.cliConstraints.supportsAllowLibraryPacksInResolveQueries()) {
+      // All of our usage of `codeql resolve queries` needs to handle library packs.
+      args.push('--allow-library-packs');
+    }
     args.push(suite);
     return this.runJsonCodeQlCliCommand<string[]>(
       ['resolve', 'queries'],
@@ -688,8 +928,52 @@ export class CodeQLCliServer implements Disposable {
     );
   }
 
+  /**
+   * Downloads a specified pack.
+   * @param packs The `<package-scope/name[@version]>` of the packs to download.
+   */
+  async packDownload(packs: string[]) {
+    return this.runJsonCodeQlCliCommand(['pack', 'download'], packs, 'Downloading packs');
+  }
+
+  async packInstall(dir: string, forceUpdate = false) {
+    const args = [dir];
+    if (forceUpdate) {
+      args.push('--mode', 'update');
+    }
+    return this.runJsonCodeQlCliCommand(['pack', 'install'], args, 'Installing pack dependencies');
+  }
+
+  async packBundle(dir: string, workspaceFolders: string[], outputPath: string, precompile = true): Promise<void> {
+    const args = [
+      '-o',
+      outputPath,
+      dir,
+      ...this.getAdditionalPacksArg(workspaceFolders)
+    ];
+    if (!precompile && await this.cliConstraints.supportsNoPrecompile()) {
+      args.push('--no-precompile');
+    }
+
+    return this.runJsonCodeQlCliCommand(['pack', 'bundle'], args, 'Bundling pack');
+  }
+
+  async packPacklist(dir: string, includeQueries: boolean): Promise<string[]> {
+    const args = includeQueries ? [dir] : ['--no-include-queries', dir];
+    // since 2.7.1, packlist returns an object with a "paths" property that is a list of packs.
+    // previous versions return a list of packs.
+    const results: { paths: string[] } | string[] = await this.runJsonCodeQlCliCommand(['pack', 'packlist'], args, 'Generating the pack list');
+
+    // Once we no longer need to support 2.7.0 or earlier, we can remove this and assume all versions return an object.
+    if ('paths' in results) {
+      return results.paths;
+    } else {
+      return results;
+    }
+  }
+
   async generateDil(qloFile: string, outFile: string): Promise<void> {
-    const extraArgs = (await this.getVersion()).compare(CodeQLCliServer.CLI_VERSION_WITH_DECOMPILE_KIND_DIL) >= 0
+    const extraArgs = await this.cliConstraints.supportsDecompileDil()
       ? ['--kind', 'dil', '-o', outFile, qloFile]
       : ['-o', outFile, qloFile];
     await this.runCodeQlCliCommand(
@@ -699,11 +983,15 @@ export class CodeQLCliServer implements Disposable {
     );
   }
 
-  private async getVersion() {
+  public async getVersion() {
     if (!this._version) {
-      this._version = await this.refreshVersion();
+      this._version = this.refreshVersion();
+      // this._version is only undefined upon config change, so we reset CLI-based context key only when necessary.
+      await commands.executeCommand(
+        'setContext', 'codeql.supportsEvalLog', await this.cliConstraints.supportsPerQueryEvalLog()
+      );
     }
-    return this._version;
+    return await this._version;
   }
 
   private async refreshVersion() {
@@ -720,6 +1008,12 @@ export class CodeQLCliServer implements Disposable {
         throw new Error('No distribution found');
     }
   }
+
+  private getAdditionalPacksArg(paths: string[]): string[] {
+    return paths.length
+      ? ['--additional-packs', paths.join(path.delimiter)]
+      : [];
+  }
 }
 
 /**
@@ -755,7 +1049,7 @@ export function spawnServer(
   if (progressReporter !== undefined) {
     progressReporter.report({ message: `Starting ${name}` });
   }
-  logger.log(`Starting ${name} using CodeQL CLI: ${base} ${argsString}`);
+  void logger.log(`Starting ${name} using CodeQL CLI: ${base} ${argsString}`);
   const child = child_process.spawn(base, args);
   if (!child || !child.pid) {
     throw new Error(`Failed to start ${name} using command ${base} ${argsString}.`);
@@ -771,7 +1065,7 @@ export function spawnServer(
   if (progressReporter !== undefined) {
     progressReporter.report({ message: `Started ${name}` });
   }
-  logger.log(`${name} started on PID: ${child.pid}`);
+  void logger.log(`${name} started on PID: ${child.pid}`);
   return child;
 }
 
@@ -800,13 +1094,13 @@ export async function runCodeQlCliCommand(
     if (progressReporter !== undefined) {
       progressReporter.report({ message: description });
     }
-    logger.log(`${description} using CodeQL CLI: ${codeQlPath} ${argsString}...`);
+    void logger.log(`${description} using CodeQL CLI: ${codeQlPath} ${argsString}...`);
     const result = await promisify(child_process.execFile)(codeQlPath, args);
-    logger.log(result.stderr);
-    logger.log('CLI command succeeded.');
+    void logger.log(result.stderr);
+    void logger.log('CLI command succeeded.');
     return result.stdout;
   } catch (err) {
-    throw new Error(`${description} failed: ${err.stderr || err}`);
+    throw new Error(`${description} failed: ${(err as any).stderr || getErrorMessage(err)}`);
   }
 }
 
@@ -839,6 +1133,20 @@ class SplitBuffer {
     this.buffer += this.separators[0];  // Append a separator to the end to ensure the last line is returned.
   }
 
+  /**
+   * A version of startsWith that isn't overriden by a broken version of ms-python.
+   *
+   * The definition comes from
+   * https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/startsWith
+   * which is CC0/public domain
+   *
+   * See https://github.com/github/vscode-codeql/issues/802 for more context as to why we need it.
+   */
+  private static startsWith(s: string, searchString: string, position: number): boolean {
+    const pos = position > 0 ? position | 0 : 0;
+    return s.substring(pos, pos + searchString.length) === searchString;
+  }
+
   /**
    * Extract the next full line from the buffer, if one is available.
    * @returns The text of the next available full line (without the separator), or `undefined` if no
@@ -847,9 +1155,9 @@ class SplitBuffer {
   public getNextLine(): string | undefined {
     while (this.searchIndex <= (this.buffer.length - this.maxSeparatorLength)) {
       for (const separator of this.separators) {
-        if (this.buffer.startsWith(separator, this.searchIndex)) {
-          const line = this.buffer.substr(0, this.searchIndex);
-          this.buffer = this.buffer.substr(this.searchIndex + separator.length);
+        if (SplitBuffer.startsWith(this.buffer, separator, this.searchIndex)) {
+          const line = this.buffer.slice(0, this.searchIndex);
+          this.buffer = this.buffer.slice(this.searchIndex + separator.length);
           this.searchIndex = 0;
           return line;
         }
@@ -904,7 +1212,8 @@ const lineEndings = ['\r\n', '\r', '\n'];
  */
 async function logStream(stream: Readable, logger: Logger): Promise<void> {
   for await (const line of await splitStreamAtSeparators(stream, lineEndings)) {
-    logger.log(line);
+    // Await the result of log here in order to ensure the logs are written in the correct order.
+    await logger.log(line);
   }
 }
 
@@ -920,3 +1229,193 @@ export function shouldDebugQueryServer() {
     && process.env.QUERY_SERVER_JAVA_DEBUG !== '0'
     && process.env.QUERY_SERVER_JAVA_DEBUG?.toLocaleLowerCase() !== 'false';
 }
+
+export function shouldDebugCliServer() {
+  return 'CLI_SERVER_JAVA_DEBUG' in process.env
+    && process.env.CLI_SERVER_JAVA_DEBUG !== '0'
+    && process.env.CLI_SERVER_JAVA_DEBUG?.toLocaleLowerCase() !== 'false';
+}
+
+export class CliVersionConstraint {
+
+  /**
+   * CLI version where --kind=DIL was introduced
+   */
+  public static CLI_VERSION_WITH_DECOMPILE_KIND_DIL = new SemVer('2.3.0');
+
+  /**
+   * CLI version where languages are exposed during a `codeql resolve database` command.
+   */
+  public static CLI_VERSION_WITH_LANGUAGE = new SemVer('2.4.1');
+
+
+  public static CLI_VERSION_WITH_NONDESTURCTIVE_UPGRADES = new SemVer('2.4.2');
+
+  /**
+   * CLI version where `codeql resolve upgrades` supports
+   * the `--allow-downgrades` flag
+   */
+  public static CLI_VERSION_WITH_DOWNGRADES = new SemVer('2.4.4');
+
+  /**
+   * CLI version where the `codeql resolve qlref` command is available.
+   */
+  public static CLI_VERSION_WITH_RESOLVE_QLREF = new SemVer('2.5.1');
+
+  /**
+   * CLI version where database registration was introduced
+   */
+  public static CLI_VERSION_WITH_DB_REGISTRATION = new SemVer('2.4.1');
+
+  /**
+   * CLI version where the `--allow-library-packs` option to `codeql resolve queries` was
+   * introduced.
+   */
+  public static CLI_VERSION_WITH_ALLOW_LIBRARY_PACKS_IN_RESOLVE_QUERIES = new SemVer('2.6.1');
+
+  /**
+   * CLI version where the `database unbundle` subcommand was introduced.
+   */
+  public static CLI_VERSION_WITH_DATABASE_UNBUNDLE = new SemVer('2.6.0');
+
+  /**
+   * CLI version where the `--no-precompile` option for pack creation was introduced.
+   */
+  public static CLI_VERSION_WITH_NO_PRECOMPILE = new SemVer('2.7.1');
+
+  /**
+   * CLI version where remote queries (variant analysis) are supported.
+   */
+  public static CLI_VERSION_REMOTE_QUERIES = new SemVer('2.6.3');
+
+  /**
+   * CLI version where the `resolve ml-models` subcommand was introduced.
+   */
+  public static CLI_VERSION_WITH_RESOLVE_ML_MODELS = new SemVer('2.7.3');
+
+  /**
+   * CLI version where the `resolve ml-models` subcommand was enhanced to work with packaging.
+   */
+  public static CLI_VERSION_WITH_PRECISE_RESOLVE_ML_MODELS = new SemVer('2.10.0');
+
+  /**
+   * CLI version where the `--old-eval-stats` option to the query server was introduced.
+   */
+  public static CLI_VERSION_WITH_OLD_EVAL_STATS = new SemVer('2.7.4');
+
+  /**
+   * CLI version where packaging was introduced.
+   */
+  public static CLI_VERSION_WITH_PACKAGING = new SemVer('2.6.0');
+
+  /**
+   * CLI version where the `--evaluator-log` and related options to the query server were introduced,
+   * on a per-query server basis.
+   */
+  public static CLI_VERSION_WITH_STRUCTURED_EVAL_LOG = new SemVer('2.8.2');
+
+  /**
+   * CLI version that supports rotating structured logs to produce one per query.
+   *
+   * Note that 2.8.4 supports generating the evaluation logs and summaries,
+   * but 2.9.0 includes a new option to produce the end-of-query summary logs to
+   * the query server console. For simplicity we gate all features behind 2.9.0,
+   * but if a user is tied to the 2.8 release, we can enable evaluator logs
+   * and summaries for them.
+   */
+  public static CLI_VERSION_WITH_PER_QUERY_EVAL_LOG = new SemVer('2.9.0');
+
+  /**
+   * CLI version that supports the `--sourcemap` option for log generation.
+   */
+  public static CLI_VERSION_WITH_SOURCEMAP = new SemVer('2.10.3');
+
+  /**
+   * CLI version that supports the new query server.
+   */
+  public static CLI_VERSION_WITH_NEW_QUERY_SERVER = new SemVer('2.11.0');
+
+  constructor(private readonly cli: CodeQLCliServer) {
+    /**/
+  }
+
+  private async isVersionAtLeast(v: SemVer) {
+    return (await this.cli.getVersion()).compare(v) >= 0;
+  }
+
+  public async supportsDecompileDil() {
+    return this.isVersionAtLeast(CliVersionConstraint.CLI_VERSION_WITH_DECOMPILE_KIND_DIL);
+  }
+
+  public async supportsLanguageName() {
+    return this.isVersionAtLeast(CliVersionConstraint.CLI_VERSION_WITH_LANGUAGE);
+  }
+
+  public async supportsNonDestructiveUpgrades() {
+    return this.isVersionAtLeast(CliVersionConstraint.CLI_VERSION_WITH_NONDESTURCTIVE_UPGRADES);
+  }
+
+  public async supportsDowngrades() {
+    return this.isVersionAtLeast(CliVersionConstraint.CLI_VERSION_WITH_DOWNGRADES);
+  }
+
+  public async supportsResolveQlref() {
+    return this.isVersionAtLeast(CliVersionConstraint.CLI_VERSION_WITH_RESOLVE_QLREF);
+  }
+
+  public async supportsAllowLibraryPacksInResolveQueries() {
+    return this.isVersionAtLeast(CliVersionConstraint.CLI_VERSION_WITH_ALLOW_LIBRARY_PACKS_IN_RESOLVE_QUERIES);
+  }
+
+  async supportsDatabaseRegistration() {
+    return this.isVersionAtLeast(CliVersionConstraint.CLI_VERSION_WITH_DB_REGISTRATION);
+  }
+
+  async supportsDatabaseUnbundle() {
+    return this.isVersionAtLeast(CliVersionConstraint.CLI_VERSION_WITH_DATABASE_UNBUNDLE);
+  }
+
+  async supportsNoPrecompile() {
+    return this.isVersionAtLeast(CliVersionConstraint.CLI_VERSION_WITH_NO_PRECOMPILE);
+  }
+
+  async supportsRemoteQueries() {
+    return this.isVersionAtLeast(CliVersionConstraint.CLI_VERSION_REMOTE_QUERIES);
+  }
+
+  async supportsResolveMlModels() {
+    return this.isVersionAtLeast(CliVersionConstraint.CLI_VERSION_WITH_RESOLVE_ML_MODELS);
+  }
+
+  async supportsPreciseResolveMlModels() {
+    return this.isVersionAtLeast(CliVersionConstraint.CLI_VERSION_WITH_PRECISE_RESOLVE_ML_MODELS);
+  }
+
+  async supportsOldEvalStats() {
+    return this.isVersionAtLeast(CliVersionConstraint.CLI_VERSION_WITH_OLD_EVAL_STATS);
+  }
+
+  async supportsPackaging() {
+    return this.isVersionAtLeast(CliVersionConstraint.CLI_VERSION_WITH_PACKAGING);
+  }
+
+  async supportsStructuredEvalLog() {
+    return this.isVersionAtLeast(CliVersionConstraint.CLI_VERSION_WITH_STRUCTURED_EVAL_LOG);
+  }
+
+  async supportsPerQueryEvalLog() {
+    return this.isVersionAtLeast(CliVersionConstraint.CLI_VERSION_WITH_PER_QUERY_EVAL_LOG);
+  }
+
+  async supportsSourceMap() {
+    return this.isVersionAtLeast(CliVersionConstraint.CLI_VERSION_WITH_SOURCEMAP);
+  }
+
+  async supportsNewQueryServer() {
+    // TODO while under development, users _must_ opt-in to the new query server
+    // by setting the `codeql.canaryQueryServer` setting to `true`.
+    // Ignore the version check for now.
+    return allowCanaryQueryServer();
+    // return this.isVersionAtLeast(CliVersionConstraint.CLI_VERSION_WITH_NEW_QUERY_SERVER);
+  }
+}

extensions/ql-vscode/src/commandRunner.ts

@@ -0,0 +1,246 @@
+import {
+  CancellationToken,
+  ProgressOptions,
+  window as Window,
+  commands,
+  Disposable,
+  ProgressLocation
+} from 'vscode';
+import { showAndLogErrorMessage, showAndLogWarningMessage } from './helpers';
+import { logger } from './logging';
+import { getErrorMessage, getErrorStack } from './pure/helpers-pure';
+import { telemetryListener } from './telemetry';
+
+export class UserCancellationException extends Error {
+  /**
+   * @param message The error message
+   * @param silent If silent is true, then this exception will avoid showing a warning message to the user.
+   */
+  constructor(message?: string, public readonly silent = false) {
+    super(message);
+  }
+}
+
+export interface ProgressUpdate {
+  /**
+   * The current step
+   */
+  step: number;
+  /**
+   * The maximum step. This *should* be constant for a single job.
+   */
+  maxStep: number;
+  /**
+   * The current progress message
+   */
+  message: string;
+}
+
+export type ProgressCallback = (p: ProgressUpdate) => void;
+
+/**
+ * A task that handles command invocations from `commandRunner`
+ * and includes a progress monitor.
+ *
+ *
+ * Arguments passed to the command handler are passed along,
+ * untouched to this `ProgressTask` instance.
+ *
+ * @param progress a progress handler function. Call this
+ * function with a `ProgressUpdate` instance in order to
+ * denote some progress being achieved on this task.
+ * @param token a cencellation token
+ * @param args arguments passed to this task passed on from
+ * `commands.registerCommand`.
+ */
+export type ProgressTask<R> = (
+  progress: ProgressCallback,
+  token: CancellationToken,
+  ...args: any[]
+) => Thenable<R>;
+
+/**
+ * A task that handles command invocations from `commandRunner`.
+ * Arguments passed to the command handler are passed along,
+ * untouched to this `NoProgressTask` instance.
+ *
+ * @param args arguments passed to this task passed on from
+ * `commands.registerCommand`.
+ */
+type NoProgressTask = ((...args: any[]) => Promise<any>);
+
+/**
+ * This mediates between the kind of progress callbacks we want to
+ * write (where we *set* current progress position and give
+ * `maxSteps`) and the kind vscode progress api expects us to write
+ * (which increment progress by a certain amount out of 100%).
+ *
+ * Where possible, the `commandRunner` function below should be used
+ * instead of this function. The commandRunner is meant for wrapping
+ * top-level commands and provides error handling and other support
+ * automatically.
+ *
+ * Only use this function if you need a progress monitor and the
+ * control flow does not always come from a command (eg- during
+ * extension activation, or from an internal language server
+ * request).
+ */
+export function withProgress<R>(
+  options: ProgressOptions,
+  task: ProgressTask<R>,
+  ...args: any[]
+): Thenable<R> {
+  let progressAchieved = 0;
+  return Window.withProgress(options,
+    (progress, token) => {
+      return task(p => {
+        const { message, step, maxStep } = p;
+        const increment = 100 * (step - progressAchieved) / maxStep;
+        progressAchieved = step;
+        progress.report({ message, increment });
+      }, token, ...args);
+    });
+}
+
+/**
+ * A generic wrapper for command registration. This wrapper adds uniform error handling for commands.
+ *
+ * In this variant of the command runner, no progress monitor is used.
+ *
+ * @param commandId The ID of the command to register.
+ * @param task The task to run. It is passed directly to `commands.registerCommand`. Any
+ * arguments to the command handler are passed on to the task.
+ */
+export function commandRunner(
+  commandId: string,
+  task: NoProgressTask,
+): Disposable {
+  return commands.registerCommand(commandId, async (...args: any[]) => {
+    const startTime = Date.now();
+    let error: Error | undefined;
+
+    try {
+      return await task(...args);
+    } catch (e) {
+      const errorMessage = `${getErrorMessage(e) || e} (${commandId})`;
+      error = e instanceof Error ? e : new Error(errorMessage);
+      const errorStack = getErrorStack(e);
+      if (e instanceof UserCancellationException) {
+        // User has cancelled this action manually
+        if (e.silent) {
+          void logger.log(errorMessage);
+        } else {
+          void showAndLogWarningMessage(errorMessage);
+        }
+      } else {
+        // Include the full stack in the error log only.
+        const fullMessage = errorStack
+          ? `${errorMessage}\n${errorStack}`
+          : errorMessage;
+        void showAndLogErrorMessage(errorMessage, {
+          fullMessage
+        });
+      }
+      return undefined;
+    } finally {
+      const executionTime = Date.now() - startTime;
+      telemetryListener.sendCommandUsage(commandId, executionTime, error);
+    }
+  });
+}
+
+/**
+ * A generic wrapper for command registration.  This wrapper adds uniform error handling,
+ * progress monitoring, and cancellation for commands.
+ *
+ * @param commandId The ID of the command to register.
+ * @param task The task to run. It is passed directly to `commands.registerCommand`. Any
+ * arguments to the command handler are passed on to the task after the progress callback
+ * and cancellation token.
+ * @param progressOptions Progress options to be sent to the progress monitor.
+ */
+export function commandRunnerWithProgress<R>(
+  commandId: string,
+  task: ProgressTask<R>,
+  progressOptions: Partial<ProgressOptions>,
+  outputLogger = logger
+): Disposable {
+  return commands.registerCommand(commandId, async (...args: any[]) => {
+    const startTime = Date.now();
+    let error: Error | undefined;
+    const progressOptionsWithDefaults = {
+      location: ProgressLocation.Notification,
+      ...progressOptions
+    };
+    try {
+      return await withProgress(progressOptionsWithDefaults, task, ...args);
+    } catch (e) {
+      const errorMessage = `${getErrorMessage(e) || e} (${commandId})`;
+      error = e instanceof Error ? e : new Error(errorMessage);
+      const errorStack = getErrorStack(e);
+      if (e instanceof UserCancellationException) {
+        // User has cancelled this action manually
+        if (e.silent) {
+          void outputLogger.log(errorMessage);
+        } else {
+          void showAndLogWarningMessage(errorMessage, { outputLogger });
+        }
+      } else {
+        // Include the full stack in the error log only.
+        const fullMessage = errorStack
+          ? `${errorMessage}\n${errorStack}`
+          : errorMessage;
+        void showAndLogErrorMessage(errorMessage, {
+          outputLogger,
+          fullMessage
+        });
+      }
+      return undefined;
+    } finally {
+      const executionTime = Date.now() - startTime;
+      telemetryListener.sendCommandUsage(commandId, executionTime, error);
+    }
+  });
+}
+
+/**
+ * Displays a progress monitor that indicates how much progess has been made
+ * reading from a stream.
+ *
+ * @param readable The stream to read progress from
+ * @param messagePrefix A prefix for displaying the message
+ * @param totalNumBytes Total number of bytes in this stream
+ * @param progress The progress callback used to set messages
+ */
+export function reportStreamProgress(
+  readable: NodeJS.ReadableStream,
+  messagePrefix: string,
+  totalNumBytes?: number,
+  progress?: ProgressCallback
+) {
+  if (progress && totalNumBytes) {
+    let numBytesDownloaded = 0;
+    const bytesToDisplayMB = (numBytes: number): string => `${(numBytes / (1024 * 1024)).toFixed(1)} MB`;
+    const updateProgress = () => {
+      progress({
+        step: numBytesDownloaded,
+        maxStep: totalNumBytes,
+        message: `${messagePrefix} [${bytesToDisplayMB(numBytesDownloaded)} of ${bytesToDisplayMB(totalNumBytes)}]`,
+      });
+    };
+
+    // Display the progress straight away rather than waiting for the first chunk.
+    updateProgress();
+
+    readable.on('data', data => {
+      numBytesDownloaded += data.length;
+      updateProgress();
+    });
+  } else if (progress) {
+    progress({
+      step: 1,
+      maxStep: 2,
+      message: `${messagePrefix} (Size unknown)`,
+    });
+  }
+}

extensions/ql-vscode/src/compare/compare-view.ts

@@ -1,15 +1,8 @@
-import { DisposableObject } from '../vscode-utils/disposable-object';
 import {
-  WebviewPanel,
   ExtensionContext,
-  window as Window,
   ViewColumn,
-  Uri,
 } from 'vscode';
-import * as path from 'path';
 
-import { tmpDir } from '../run-queries';
-import { CompletedQuery } from '../query-results';
 import {
   FromCompareViewMessage,
   ToCompareViewMessage,
@@ -18,36 +11,38 @@ import {
 import { Logger } from '../logging';
 import { CodeQLCliServer } from '../cli';
 import { DatabaseManager } from '../databases';
-import { getHtmlForWebview, jumpToLocation } from '../interface-utils';
+import { jumpToLocation } from '../interface-utils';
 import { transformBqrsResultSet, RawResultSet, BQRSInfo } from '../pure/bqrs-cli-types';
 import resultsDiff from './resultsDiff';
+import { CompletedLocalQueryInfo } from '../query-results';
+import { getErrorMessage } from '../pure/helpers-pure';
+import { HistoryItemLabelProvider } from '../history-item-label-provider';
+import { AbstractWebview, WebviewPanelConfig } from '../abstract-webview';
 
 interface ComparePair {
-  from: CompletedQuery;
-  to: CompletedQuery;
+  from: CompletedLocalQueryInfo;
+  to: CompletedLocalQueryInfo;
 }
 
-export class CompareInterfaceManager extends DisposableObject {
+export class CompareView extends AbstractWebview<ToCompareViewMessage, FromCompareViewMessage> {
   private comparePair: ComparePair | undefined;
-  private panel: WebviewPanel | undefined;
-  private panelLoaded = false;
-  private panelLoadedCallBacks: (() => void)[] = [];
 
   constructor(
-    private ctx: ExtensionContext,
+    ctx: ExtensionContext,
     private databaseManager: DatabaseManager,
     private cliServer: CodeQLCliServer,
     private logger: Logger,
+    private labelProvider: HistoryItemLabelProvider,
     private showQueryResultsCallback: (
-      item: CompletedQuery
+      item: CompletedLocalQueryInfo
     ) => Promise<void>
   ) {
-    super();
+    super(ctx);
   }
 
   async showResults(
-    from: CompletedQuery,
-    to: CompletedQuery,
+    from: CompletedLocalQueryInfo,
+    to: CompletedLocalQueryInfo,
     selectedResultSetName?: string
   ) {
     this.comparePair = { from, to };
@@ -70,7 +65,7 @@ export class CompareInterfaceManager extends DisposableObject {
       try {
         rows = this.compareResults(fromResultSet, toResultSet);
       } catch (e) {
-        message = e.message;
+        message = getErrorMessage(e);
       }
 
       await this.postMessage({
@@ -80,18 +75,14 @@ export class CompareInterfaceManager extends DisposableObject {
             // since we split the description into several rows
             // only run interpolation if the label is user-defined
             // otherwise we will wind up with duplicated rows
-            name: from.options.label
-              ? from.interpolate(from.getLabel())
-              : from.queryName,
-            status: from.statusString,
-            time: from.time,
+            name: this.labelProvider.getShortLabel(from),
+            status: from.completedQuery.statusString,
+            time: from.startTime,
           },
           toQuery: {
-            name: to.options.label
-              ? to.interpolate(to.getLabel())
-              : to.queryName,
-            status: to.statusString,
-            time: to.time,
+            name: this.labelProvider.getShortLabel(to),
+            status: to.completedQuery.statusString,
+            time: to.startTime,
           },
         },
         columns: fromResultSet.schema.columns,
@@ -99,81 +90,33 @@ export class CompareInterfaceManager extends DisposableObject {
         currentResultSetName: currentResultSetName,
         rows,
         message,
-        datebaseUri: to.database.databaseUri,
+        databaseUri: to.initialInfo.databaseInfo.databaseUri,
       });
     }
   }
 
-  getPanel(): WebviewPanel {
-    if (this.panel == undefined) {
-      const { ctx } = this;
-      const panel = (this.panel = Window.createWebviewPanel(
-        'compareView',
-        'Compare CodeQL Query Results',
-        { viewColumn: ViewColumn.Active, preserveFocus: true },
-        {
-          enableScripts: true,
-          enableFindWidget: true,
-          retainContextWhenHidden: true,
-          localResourceRoots: [
-            Uri.file(tmpDir.name),
-            Uri.file(path.join(this.ctx.extensionPath, 'out')),
-          ],
-        }
-      ));
-      this.panel.onDidDispose(
-        () => {
-          this.panel = undefined;
-          this.comparePair = undefined;
-        },
-        null,
-        ctx.subscriptions
-      );
-
-      const scriptPathOnDisk = Uri.file(
-        ctx.asAbsolutePath('out/compareView.js')
-      );
-
-      const stylesheetPathOnDisk = Uri.file(
-        ctx.asAbsolutePath('out/resultsView.css')
-      );
-
-      panel.webview.html = getHtmlForWebview(
-        panel.webview,
-        scriptPathOnDisk,
-        stylesheetPathOnDisk
-      );
-      panel.webview.onDidReceiveMessage(
-        async (e) => this.handleMsgFromView(e),
-        undefined,
-        ctx.subscriptions
-      );
-    }
-    return this.panel;
+  protected getPanelConfig(): WebviewPanelConfig {
+    return {
+      viewId: 'compareView',
+      title: 'Compare CodeQL Query Results',
+      viewColumn: ViewColumn.Active,
+      preserveFocus: true,
+      view: 'compare',
+    };
   }
 
-  private waitForPanelLoaded(): Promise<void> {
-    return new Promise((resolve) => {
-      if (this.panelLoaded) {
-        resolve();
-      } else {
-        this.panelLoadedCallBacks.push(resolve);
-      }
-    });
+  protected onPanelDispose(): void {
+    this.comparePair = undefined;
   }
 
-  private async handleMsgFromView(
-    msg: FromCompareViewMessage
-  ): Promise<void> {
+  protected async onMessage(msg: FromCompareViewMessage): Promise<void> {
     switch (msg.t) {
-      case 'compareViewLoaded':
-        this.panelLoaded = true;
-        this.panelLoadedCallBacks.forEach((cb) => cb());
-        this.panelLoadedCallBacks = [];
+      case 'viewLoaded':
+        this.onWebViewLoaded();
         break;
 
       case 'changeCompare':
-        this.changeTable(msg.newResultSetName);
+        await this.changeTable(msg.newResultSetName);
         break;
 
       case 'viewSourceFile':
@@ -186,20 +129,16 @@ export class CompareInterfaceManager extends DisposableObject {
     }
   }
 
-  private postMessage(msg: ToCompareViewMessage): Thenable<boolean> {
-    return this.getPanel().webview.postMessage(msg);
-  }
-
   private async findCommonResultSetNames(
-    from: CompletedQuery,
-    to: CompletedQuery,
+    from: CompletedLocalQueryInfo,
+    to: CompletedLocalQueryInfo,
     selectedResultSetName: string | undefined
   ): Promise<[string[], string, RawResultSet, RawResultSet]> {
     const fromSchemas = await this.cliServer.bqrsInfo(
-      from.query.resultsPaths.resultsPath
+      from.completedQuery.query.resultsPaths.resultsPath
     );
     const toSchemas = await this.cliServer.bqrsInfo(
-      to.query.resultsPaths.resultsPath
+      to.completedQuery.query.resultsPaths.resultsPath
     );
     const fromSchemaNames = fromSchemas['result-sets'].map(
       (schema) => schema.name
@@ -215,12 +154,12 @@ export class CompareInterfaceManager extends DisposableObject {
     const fromResultSet = await this.getResultSet(
       fromSchemas,
       currentResultSetName,
-      from.query.resultsPaths.resultsPath
+      from.completedQuery.query.resultsPaths.resultsPath
     );
     const toResultSet = await this.getResultSet(
       toSchemas,
       currentResultSetName,
-      to.query.resultsPaths.resultsPath
+      to.completedQuery.query.resultsPaths.resultsPath
     );
     return [
       commonResultSetNames,
@@ -267,11 +206,11 @@ export class CompareInterfaceManager extends DisposableObject {
     return resultsDiff(fromResults, toResults);
   }
 
-  private openQuery(kind: 'from' | 'to') {
+  private async openQuery(kind: 'from' | 'to') {
     const toOpen =
       kind === 'from' ? this.comparePair?.from : this.comparePair?.to;
     if (toOpen) {
-      this.showQueryResultsCallback(toOpen);
+      await this.showQueryResultsCallback(toOpen);
     }
   }
 }

extensions/ql-vscode/src/config.ts

@@ -1,16 +1,20 @@
-import { DisposableObject } from './vscode-utils/disposable-object';
+import { DisposableObject } from './pure/disposable-object';
 import { workspace, Event, EventEmitter, ConfigurationChangeEvent, ConfigurationTarget } from 'vscode';
 import { DistributionManager } from './distribution';
 import { logger } from './logging';
+import { ONE_DAY_IN_MS } from './pure/time';
+
+export const ALL_SETTINGS: Setting[] = [];
 
 /** Helper class to look up a labelled (and possibly nested) setting. */
-class Setting {
+export class Setting {
   name: string;
   parent?: Setting;
 
   constructor(name: string, parent?: Setting) {
     this.name = name;
     this.parent = parent;
+    ALL_SETTINGS.push(this);
   }
 
   get qualifiedName(): string {
@@ -35,24 +39,49 @@ class Setting {
     return workspace.getConfiguration(this.parent.qualifiedName).update(this.name, value, target);
   }
 
+  inspect<T>(): InspectionResult<T> | undefined {
+    if (this.parent === undefined) {
+      throw new Error('Cannot update the value of a root setting.');
+    }
+    return workspace.getConfiguration(this.parent.qualifiedName).inspect(this.name);
+  }
+}
+
+export interface InspectionResult<T> {
+  globalValue?: T;
+  workspaceValue?: T,
+  workspaceFolderValue?: T,
 }
 
 const ROOT_SETTING = new Setting('codeQL');
 
-// Distribution configuration
+// Global configuration
+const TELEMETRY_SETTING = new Setting('telemetry', ROOT_SETTING);
+const AST_VIEWER_SETTING = new Setting('astViewer', ROOT_SETTING);
+const GLOBAL_TELEMETRY_SETTING = new Setting('telemetry');
 
+export const LOG_TELEMETRY = new Setting('logTelemetry', TELEMETRY_SETTING);
+export const ENABLE_TELEMETRY = new Setting('enableTelemetry', TELEMETRY_SETTING);
+
+export const GLOBAL_ENABLE_TELEMETRY = new Setting('enableTelemetry', GLOBAL_TELEMETRY_SETTING);
+
+// Distribution configuration
 const DISTRIBUTION_SETTING = new Setting('cli', ROOT_SETTING);
-const CUSTOM_CODEQL_PATH_SETTING = new Setting('executablePath', DISTRIBUTION_SETTING);
+export const CUSTOM_CODEQL_PATH_SETTING = new Setting('executablePath', DISTRIBUTION_SETTING);
 const INCLUDE_PRERELEASE_SETTING = new Setting('includePrerelease', DISTRIBUTION_SETTING);
 const PERSONAL_ACCESS_TOKEN_SETTING = new Setting('personalAccessToken', DISTRIBUTION_SETTING);
+
+// Query History configuration
 const QUERY_HISTORY_SETTING = new Setting('queryHistory', ROOT_SETTING);
 const QUERY_HISTORY_FORMAT_SETTING = new Setting('format', QUERY_HISTORY_SETTING);
+const QUERY_HISTORY_TTL = new Setting('ttl', QUERY_HISTORY_SETTING);
 
 /** When these settings change, the distribution should be updated. */
 const DISTRIBUTION_CHANGE_SETTINGS = [CUSTOM_CODEQL_PATH_SETTING, INCLUDE_PRERELEASE_SETTING, PERSONAL_ACCESS_TOKEN_SETTING];
 
 export interface DistributionConfig {
-  customCodeQlPath?: string;
+  readonly customCodeQlPath?: string;
+  updateCustomCodeQlPath: (newPath: string | undefined) => Promise<void>;
   includePrerelease: boolean;
   personalAccessToken?: string;
   ownerName?: string;
@@ -61,49 +90,63 @@ export interface DistributionConfig {
 }
 
 // Query server configuration
-
 const RUNNING_QUERIES_SETTING = new Setting('runningQueries', ROOT_SETTING);
 const NUMBER_OF_THREADS_SETTING = new Setting('numberOfThreads', RUNNING_QUERIES_SETTING);
+const SAVE_CACHE_SETTING = new Setting('saveCache', RUNNING_QUERIES_SETTING);
+const CACHE_SIZE_SETTING = new Setting('cacheSize', RUNNING_QUERIES_SETTING);
 const TIMEOUT_SETTING = new Setting('timeout', RUNNING_QUERIES_SETTING);
 const MEMORY_SETTING = new Setting('memory', RUNNING_QUERIES_SETTING);
 const DEBUG_SETTING = new Setting('debug', RUNNING_QUERIES_SETTING);
+const MAX_PATHS = new Setting('maxPaths', RUNNING_QUERIES_SETTING);
 const RUNNING_TESTS_SETTING = new Setting('runningTests', ROOT_SETTING);
 const RESULTS_DISPLAY_SETTING = new Setting('resultsDisplay', ROOT_SETTING);
 
+export const ADDITIONAL_TEST_ARGUMENTS_SETTING = new Setting('additionalTestArguments', RUNNING_TESTS_SETTING);
 export const NUMBER_OF_TEST_THREADS_SETTING = new Setting('numberOfThreads', RUNNING_TESTS_SETTING);
 export const MAX_QUERIES = new Setting('maxQueries', RUNNING_QUERIES_SETTING);
 export const AUTOSAVE_SETTING = new Setting('autoSave', RUNNING_QUERIES_SETTING);
 export const PAGE_SIZE = new Setting('pageSize', RESULTS_DISPLAY_SETTING);
+const CUSTOM_LOG_DIRECTORY_SETTING = new Setting('customLogDirectory', RUNNING_QUERIES_SETTING);
 
 /** When these settings change, the running query server should be restarted. */
-const QUERY_SERVER_RESTARTING_SETTINGS = [NUMBER_OF_THREADS_SETTING, MEMORY_SETTING, DEBUG_SETTING];
+const QUERY_SERVER_RESTARTING_SETTINGS = [
+  NUMBER_OF_THREADS_SETTING, SAVE_CACHE_SETTING, CACHE_SIZE_SETTING, MEMORY_SETTING,
+  DEBUG_SETTING, CUSTOM_LOG_DIRECTORY_SETTING,
+];
 
 export interface QueryServerConfig {
   codeQlPath: string;
   debug: boolean;
   numThreads: number;
+  saveCache: boolean;
+  cacheSize: number;
   queryMemoryMb?: number;
   timeoutSecs: number;
+  customLogDirectory?: string;
   onDidChangeConfiguration?: Event<void>;
 }
 
 /** When these settings change, the query history should be refreshed. */
-const QUERY_HISTORY_SETTINGS = [QUERY_HISTORY_FORMAT_SETTING];
+const QUERY_HISTORY_SETTINGS = [QUERY_HISTORY_FORMAT_SETTING, QUERY_HISTORY_TTL];
 
 export interface QueryHistoryConfig {
   format: string;
+  ttlInMillis: number;
   onDidChangeConfiguration: Event<void>;
 }
 
-const CLI_SETTINGS = [NUMBER_OF_TEST_THREADS_SETTING];
+const CLI_SETTINGS = [ADDITIONAL_TEST_ARGUMENTS_SETTING, NUMBER_OF_TEST_THREADS_SETTING, NUMBER_OF_THREADS_SETTING, MAX_PATHS];
 
 export interface CliConfig {
+  additionalTestArguments: string[];
   numberTestThreads: number;
+  numberThreads: number;
+  maxPaths: number;
   onDidChangeConfiguration?: Event<void>;
 }
 
 
-abstract class ConfigListener extends DisposableObject {
+export abstract class ConfigListener extends DisposableObject {
   protected readonly _onDidChangeConfiguration = this.push(new EventEmitter<void>());
 
   constructor() {
@@ -128,7 +171,7 @@ abstract class ConfigListener extends DisposableObject {
 
   protected abstract handleDidChangeConfiguration(e: ConfigurationChangeEvent): void;
   private updateConfiguration(): void {
-    this._onDidChangeConfiguration.fire();
+    this._onDidChangeConfiguration.fire(undefined);
   }
 
   public get onDidChangeConfiguration(): Event<void> {
@@ -149,6 +192,10 @@ export class DistributionConfigListener extends ConfigListener implements Distri
     return PERSONAL_ACCESS_TOKEN_SETTING.getValue() || undefined;
   }
 
+  public async updateCustomCodeQlPath(newPath: string | undefined) {
+    await CUSTOM_CODEQL_PATH_SETTING.updateValue(newPath, ConfigurationTarget.Global);
+  }
+
   protected handleDidChangeConfiguration(e: ConfigurationChangeEvent): void {
     this.handleDidChangeConfigurationForRelevantSettings(DISTRIBUTION_CHANGE_SETTINGS, e);
   }
@@ -166,7 +213,7 @@ export class QueryServerConfigListener extends ConfigListener implements QuerySe
       config.push(distributionManager.onDidChangeDistribution(async () => {
         const codeQlPath = await distributionManager.getCodeQlPathWithoutVersionCheck();
         config._codeQlPath = codeQlPath!;
-        config._onDidChangeConfiguration.fire();
+        config._onDidChangeConfiguration.fire(undefined);
       }));
     }
     return config;
@@ -176,10 +223,22 @@ export class QueryServerConfigListener extends ConfigListener implements QuerySe
     return this._codeQlPath;
   }
 
+  public get customLogDirectory(): string | undefined {
+    return CUSTOM_LOG_DIRECTORY_SETTING.getValue<string>() || undefined;
+  }
+
   public get numThreads(): number {
     return NUMBER_OF_THREADS_SETTING.getValue<number>();
   }
 
+  public get saveCache(): boolean {
+    return SAVE_CACHE_SETTING.getValue<boolean>();
+  }
+
+  public get cacheSize(): number {
+    return CACHE_SIZE_SETTING.getValue<number | null>() || 0;
+  }
+
   /** Gets the configured query timeout, in seconds. This looks up the setting at the time of access. */
   public get timeoutSecs(): number {
     return TIMEOUT_SETTING.getValue<number | null>() || 0;
@@ -191,7 +250,7 @@ export class QueryServerConfigListener extends ConfigListener implements QuerySe
       return undefined;
     }
     if (memory == 0 || typeof (memory) !== 'number') {
-      logger.log(`Ignoring value '${memory}' for setting ${MEMORY_SETTING.qualifiedName}`);
+      void logger.log(`Ignoring value '${memory}' for setting ${MEMORY_SETTING.qualifiedName}`);
       return undefined;
     }
     return memory;
@@ -214,19 +273,47 @@ export class QueryHistoryConfigListener extends ConfigListener implements QueryH
   public get format(): string {
     return QUERY_HISTORY_FORMAT_SETTING.getValue<string>();
   }
+
+  /**
+   * The configuration value is in days, but return the value in milliseconds to make it easier to use.
+   */
+  public get ttlInMillis(): number {
+    return (QUERY_HISTORY_TTL.getValue<number>() || 30) * ONE_DAY_IN_MS;
+  }
 }
 
 export class CliConfigListener extends ConfigListener implements CliConfig {
+  public get additionalTestArguments(): string[] {
+    return ADDITIONAL_TEST_ARGUMENTS_SETTING.getValue();
+  }
 
   public get numberTestThreads(): number {
     return NUMBER_OF_TEST_THREADS_SETTING.getValue();
   }
 
+  public get numberThreads(): number {
+    return NUMBER_OF_THREADS_SETTING.getValue<number>();
+  }
+
+  public get maxPaths(): number {
+    return MAX_PATHS.getValue<number>();
+  }
+
   protected handleDidChangeConfiguration(e: ConfigurationChangeEvent): void {
     this.handleDidChangeConfigurationForRelevantSettings(CLI_SETTINGS, e);
   }
 }
 
+/**
+ * Whether to enable CodeLens for the 'Quick Evaluation' command.
+ */
+const QUICK_EVAL_CODELENS_SETTING = new Setting('quickEvalCodelens', RUNNING_QUERIES_SETTING);
+
+export function isQuickEvalCodelensEnabled() {
+  return QUICK_EVAL_CODELENS_SETTING.getValue<boolean>();
+}
+
+
 // Enable experimental features
 
 /**
@@ -235,3 +322,104 @@ export class CliConfigListener extends ConfigListener implements CliConfig {
  * want to enable experimental features, they can add them directly in
  * their vscode settings json file.
  */
+
+/**
+ * Enables canary features of this extension. Recommended for all internal users.
+ */
+export const CANARY_FEATURES = new Setting('canary', ROOT_SETTING);
+
+export function isCanary() {
+  return !!CANARY_FEATURES.getValue<boolean>();
+}
+
+/**
+ * Enables the experimental query server
+ */
+export const CANARY_QUERY_SERVER = new Setting('canaryQueryServer', ROOT_SETTING);
+
+
+export function allowCanaryQueryServer() {
+  return !!CANARY_QUERY_SERVER.getValue<boolean>();
+}
+
+
+/**
+ * Avoids caching in the AST viewer if the user is also a canary user.
+ */
+export const NO_CACHE_AST_VIEWER = new Setting('disableCache', AST_VIEWER_SETTING);
+
+// Settings for variant analysis
+const REMOTE_QUERIES_SETTING = new Setting('variantAnalysis', ROOT_SETTING);
+
+/**
+ * Lists of GitHub repositories that you want to query remotely via the "Run Variant Analysis" command.
+ * Note: This command is only available for internal users.
+ *
+ * This setting should be a JSON object where each key is a user-specified name (string),
+ * and the value is an array of GitHub repositories (of the form `<owner>/<repo>`).
+ */
+const REMOTE_REPO_LISTS = new Setting('repositoryLists', REMOTE_QUERIES_SETTING);
+
+export function getRemoteRepositoryLists(): Record<string, string[]> | undefined {
+  return REMOTE_REPO_LISTS.getValue<Record<string, string[]>>() || undefined;
+}
+
+export async function setRemoteRepositoryLists(lists: Record<string, string[]> | undefined) {
+  await REMOTE_REPO_LISTS.updateValue(lists, ConfigurationTarget.Global);
+}
+
+/**
+ * Path to a file that contains lists of GitHub repositories that you want to query remotely via
+ * the "Run Variant Analysis" command.
+ * Note: This command is only available for internal users.
+ *
+ * This setting should be a path to a JSON file that contains a JSON object where each key is a
+ * user-specified name (string), and the value is an array of GitHub repositories
+ * (of the form `<owner>/<repo>`).
+ */
+const REPO_LISTS_PATH = new Setting('repositoryListsPath', REMOTE_QUERIES_SETTING);
+
+export function getRemoteRepositoryListsPath(): string | undefined {
+  return REPO_LISTS_PATH.getValue<string>() || undefined;
+}
+
+/**
+ * The name of the "controller" repository that you want to use with the "Run Variant Analysis" command.
+ * Note: This command is only available for internal users.
+ *
+ * This setting should be a GitHub repository of the form `<owner>/<repo>`.
+ */
+const REMOTE_CONTROLLER_REPO = new Setting('controllerRepo', REMOTE_QUERIES_SETTING);
+
+export function getRemoteControllerRepo(): string | undefined {
+  return REMOTE_CONTROLLER_REPO.getValue<string>() || undefined;
+}
+
+export async function setRemoteControllerRepo(repo: string | undefined) {
+  await REMOTE_CONTROLLER_REPO.updateValue(repo, ConfigurationTarget.Global);
+}
+
+/**
+ * The branch of "github/codeql-variant-analysis-action" to use with the "Run Variant Analysis" command.
+ * Default value is "main".
+ * Note: This command is only available for internal users.
+ */
+const ACTION_BRANCH = new Setting('actionBranch', REMOTE_QUERIES_SETTING);
+
+export function getActionBranch(): string {
+  return ACTION_BRANCH.getValue<string>() || 'main';
+}
+
+export function isIntegrationTestMode() {
+  return process.env.INTEGRATION_TEST_MODE === 'true';
+}
+
+/**
+ * A flag indicating whether to enable the experimental "live results" feature
+ * for multi-repo variant analyses.
+ */
+const LIVE_RESULTS = new Setting('liveResults', REMOTE_QUERIES_SETTING);
+
+export function isVariantAnalysisLiveResultsEnabled(): boolean {
+  return !!LIVE_RESULTS.getValue<boolean>();
+}

extensions/ql-vscode/src/contextual/astBuilder.ts

@@ -1,9 +1,10 @@
-import { QueryWithResults } from '../run-queries';
 import { CodeQLCliServer } from '../cli';
 import { DecodedBqrsChunk, BqrsId, EntityValue } from '../pure/bqrs-cli-types';
 import { DatabaseItem } from '../databases';
 import { ChildAstItem, AstItem } from '../astViewer';
 import fileRangeFromURI from './fileRangeFromURI';
+import { Uri } from 'vscode';
+import { QueryWithResults } from '../run-queries-shared';
 
 /**
  * A class that wraps a tree of QL results from a query that
@@ -17,7 +18,7 @@ export default class AstBuilder {
     queryResults: QueryWithResults,
     private cli: CodeQLCliServer,
     public db: DatabaseItem,
-    public fileName: string
+    public fileName: Uri
   ) {
     this.bqrsPath = queryResults.query.resultsPaths.resultsPath;
   }

extensions/ql-vscode/src/contextual/keyType.ts

@@ -2,6 +2,7 @@ export enum KeyType {
   DefinitionQuery = 'DefinitionQuery',
   ReferenceQuery = 'ReferenceQuery',
   PrintAstQuery = 'PrintAstQuery',
+  PrintCfgQuery = 'PrintCfgQuery',
 }
 
 export function tagOfKeyType(keyType: KeyType): string {
@@ -12,6 +13,8 @@ export function tagOfKeyType(keyType: KeyType): string {
       return 'ide-contextual-queries/local-references';
     case KeyType.PrintAstQuery:
       return 'ide-contextual-queries/print-ast';
+    case KeyType.PrintCfgQuery:
+      return 'ide-contextual-queries/print-cfg';
   }
 }
 
@@ -23,6 +26,8 @@ export function nameOfKeyType(keyType: KeyType): string {
       return 'references';
     case KeyType.PrintAstQuery:
       return 'print AST';
+    case KeyType.PrintCfgQuery:
+      return 'print CFG';
   }
 }
 
@@ -32,6 +37,7 @@ export function kindOfKeyType(keyType: KeyType): string {
     case KeyType.ReferenceQuery:
       return 'definitions';
     case KeyType.PrintAstQuery:
+    case KeyType.PrintCfgQuery:
       return 'graph';
   }
 }

extensions/ql-vscode/src/contextual/locationFinder.ts

@@ -1,22 +1,20 @@
-import * as vscode from 'vscode';
-
 import { decodeSourceArchiveUri, encodeArchiveBasePath } from '../archive-filesystem-provider';
 import { ColumnKindCode, EntityValue, getResultSetSchema, ResultSetSchema } from '../pure/bqrs-cli-types';
 import { CodeQLCliServer } from '../cli';
 import { DatabaseManager, DatabaseItem } from '../databases';
 import fileRangeFromURI from './fileRangeFromURI';
-import * as messages from '../pure/messages';
-import { QueryServerClient } from '../queryserver-client';
-import { QueryWithResults, compileAndRunQueryAgainstDatabase } from '../run-queries';
-import { ProgressCallback } from '../helpers';
+import { ProgressCallback } from '../commandRunner';
 import { KeyType } from './keyType';
 import { qlpackOfDatabase, resolveQueries } from './queryResolver';
+import { CancellationToken, LocationLink, Uri } from 'vscode';
+import { createInitialQueryInfo, QueryWithResults } from '../run-queries-shared';
+import { QueryRunner } from '../queryRunner';
 
-const SELECT_QUERY_NAME = '#select';
+export const SELECT_QUERY_NAME = '#select';
 export const TEMPLATE_NAME = 'selectedSourceFile';
 
-export interface FullLocationLink extends vscode.LocationLink {
-  originUri: vscode.Uri;
+export interface FullLocationLink extends LocationLink {
+  originUri: Uri;
 }
 
 /**
@@ -29,21 +27,23 @@ export interface FullLocationLink extends vscode.LocationLink {
  * @param dbm The database manager
  * @param uriString The selected source file and location
  * @param keyType The contextual query type to run
+ * @param queryStorageDir The directory to store the query results
  * @param progress A progress callback
  * @param token A CancellationToken
  * @param filter A function that will filter extraneous results
  */
 export async function getLocationsForUriString(
   cli: CodeQLCliServer,
-  qs: QueryServerClient,
+  qs: QueryRunner,
   dbm: DatabaseManager,
   uriString: string,
   keyType: KeyType,
+  queryStorageDir: string,
   progress: ProgressCallback,
-  token: vscode.CancellationToken,
+  token: CancellationToken,
   filter: (src: string, dest: string) => boolean
 ): Promise<FullLocationLink[]> {
-  const uri = decodeSourceArchiveUri(vscode.Uri.parse(uriString, true));
+  const uri = decodeSourceArchiveUri(Uri.parse(uriString, true));
   const sourceArchiveUri = encodeArchiveBasePath(uri.sourceArchiveZipPath);
 
   const db = dbm.findDatabaseItemBySourceArchive(sourceArchiveUri);
@@ -52,25 +52,20 @@ export async function getLocationsForUriString(
   }
 
   const qlpack = await qlpackOfDatabase(cli, db);
-  if (qlpack === undefined) {
-    throw new Error('Can\'t infer qlpack from database source archive');
-  }
   const templates = createTemplates(uri.pathWithinSourceArchive);
 
   const links: FullLocationLink[] = [];
   for (const query of await resolveQueries(cli, qlpack, keyType)) {
-    const results = await compileAndRunQueryAgainstDatabase(
-      cli,
-      qs,
-      db,
-      false,
-      vscode.Uri.file(query),
-      progress,
-      token,
-      templates
+    const initialInfo = await createInitialQueryInfo(
+      Uri.file(query),
+      {
+        name: db.name,
+        databaseUri: db.databaseUri.toString(),
+      },
+      false
     );
-
-    if (results.result.resultType == messages.QueryResultType.SUCCESS) {
+    const results = await qs.compileAndRunQueryAgainstDatabase(db, initialInfo, queryStorageDir, progress, token, templates);
+    if (results.successful) {
       links.push(...await getLinksFromResults(results, cli, db, filter));
     }
   }
@@ -107,15 +102,9 @@ async function getLinksFromResults(
   return localLinks;
 }
 
-function createTemplates(path: string): messages.TemplateDefinitions {
+function createTemplates(path: string): Record<string, string> {
   return {
-    [TEMPLATE_NAME]: {
-      values: {
-        tuples: [[{
-          stringValue: path
-        }]]
-      }
-    }
+    [TEMPLATE_NAME]: path
   };
 }
 

extensions/ql-vscode/src/contextual/queryResolver.ts

@@ -11,37 +11,96 @@ import {
 } from './keyType';
 import { CodeQLCliServer } from '../cli';
 import { DatabaseItem } from '../databases';
+import { QlPacksForLanguage } from '../helpers';
 
-export async function qlpackOfDatabase(cli: CodeQLCliServer, db: DatabaseItem): Promise<string | undefined> {
-  if (db.contents === undefined)
-    return undefined;
+export async function qlpackOfDatabase(cli: CodeQLCliServer, db: DatabaseItem): Promise<QlPacksForLanguage> {
+  if (db.contents === undefined) {
+    throw new Error('Database is invalid and cannot infer QLPack.');
+  }
   const datasetPath = db.contents.datasetUri.fsPath;
-  const { qlpack } = await helpers.resolveDatasetFolder(cli, datasetPath);
-  return qlpack;
+  const dbscheme = await helpers.getPrimaryDbscheme(datasetPath);
+  return await helpers.getQlPackForDbscheme(cli, dbscheme);
 }
 
-
-export async function resolveQueries(cli: CodeQLCliServer, qlpack: string, keyType: KeyType): Promise<string[]> {
+/**
+ * Finds the contextual queries with the specified key in a list of CodeQL packs.
+ *
+ * @param cli The CLI instance to use.
+ * @param qlpacks The list of packs to search.
+ * @param keyType The contextual query key of the query to search for.
+ * @returns The found queries from the first pack in which any matching queries were found.
+ */
+async function resolveQueriesFromPacks(cli: CodeQLCliServer, qlpacks: string[], keyType: KeyType): Promise<string[]> {
   const suiteFile = (await tmp.file({
     postfix: '.qls'
   })).path;
-  const suiteYaml = {
-    qlpack,
-    include: {
-      kind: kindOfKeyType(keyType),
-      'tags contain': tagOfKeyType(keyType)
-    }
-  };
-  await fs.writeFile(suiteFile, yaml.safeDump(suiteYaml), 'utf8');
+  const suiteYaml = [];
+  for (const qlpack of qlpacks) {
+    suiteYaml.push({
+      from: qlpack,
+      queries: '.',
+      include: {
+        kind: kindOfKeyType(keyType),
+        'tags contain': tagOfKeyType(keyType)
+      }
+    });
+  }
+  await fs.writeFile(suiteFile, yaml.dump(suiteYaml), 'utf8');
 
   const queries = await cli.resolveQueriesInSuite(suiteFile, helpers.getOnDiskWorkspaceFolders());
-  if (queries.length === 0) {
-    helpers.showAndLogErrorMessage(
-      `No ${nameOfKeyType(keyType)} queries (tagged "${tagOfKeyType(keyType)}") could be found in the current library path. \
-      Try upgrading the CodeQL libraries. If that doesn't work, then ${nameOfKeyType(keyType)} queries are not yet available \
-      for this language.`
-    );
-    throw new Error(`Couldn't find any queries tagged ${tagOfKeyType(keyType)} for qlpack ${qlpack}`);
-  }
   return queries;
 }
+
+export async function resolveQueries(cli: CodeQLCliServer, qlpacks: QlPacksForLanguage, keyType: KeyType): Promise<string[]> {
+  const cliCanHandleLibraryPack = await cli.cliConstraints.supportsAllowLibraryPacksInResolveQueries();
+  const packsToSearch: string[] = [];
+  let blameCli: boolean;
+
+  if (cliCanHandleLibraryPack) {
+    // The CLI can handle both library packs and query packs, so search both packs in order.
+    packsToSearch.push(qlpacks.dbschemePack);
+    if (qlpacks.queryPack !== undefined) {
+      packsToSearch.push(qlpacks.queryPack);
+    }
+    // If we don't find the query, it's because it's not there, not because the CLI was unable to
+    // search the pack.
+    blameCli = false;
+  } else {
+    // Older CLIs can't handle `codeql resolve queries` with a suite that references a library pack.
+    if (qlpacks.dbschemePackIsLibraryPack) {
+      if (qlpacks.queryPack !== undefined) {
+        // Just search the query pack, because some older library/query releases still had the
+        // contextual queries in the query pack.
+        packsToSearch.push(qlpacks.queryPack);
+      }
+      // If we don't find it, it's because the CLI was unable to search the library pack that
+      // actually contains the query. Blame any failure on the CLI, not the packs.
+      blameCli = true;
+    } else {
+      // We have an old CLI, but the dbscheme pack is old enough that it's still a unified pack with
+      // both libraries and queries. Just search that pack.
+      packsToSearch.push(qlpacks.dbschemePack);
+      // Any CLI should be able to search the single query pack, so if we don't find it, it's
+      // because the language doesn't support it.
+      blameCli = false;
+    }
+  }
+
+  const queries = await resolveQueriesFromPacks(cli, packsToSearch, keyType);
+  if (queries.length > 0) {
+    return queries;
+  }
+
+  // No queries found. Determine the correct error message for the various scenarios.
+  const errorMessage = blameCli ?
+    `Your current version of the CodeQL CLI, '${(await cli.getVersion()).version}', \
+    is unable to use contextual queries from recent versions of the standard CodeQL libraries. \
+    Please upgrade to the latest version of the CodeQL CLI.`
+    :
+    `No ${nameOfKeyType(keyType)} queries (tagged "${tagOfKeyType(keyType)}") could be found in the current library path. \
+    Try upgrading the CodeQL libraries. If that doesn't work, then ${nameOfKeyType(keyType)} queries are not yet available \
+    for this language.`;
+
+  void helpers.showAndLogErrorMessage(errorMessage);
+  throw new Error(`Couldn't find any queries tagged ${tagOfKeyType(keyType)} in any of the following packs: ${packsToSearch.join(', ')}.`);
+}

extensions/ql-vscode/src/contextual/templateProvider.ts

@@ -1,18 +1,30 @@
-import * as vscode from 'vscode';
+import {
+  CancellationToken,
+  DefinitionProvider,
+  Location,
+  LocationLink,
+  Position,
+  ProgressLocation,
+  ReferenceContext,
+  ReferenceProvider,
+  TextDocument,
+  Uri
+} from 'vscode';
 
 import { decodeSourceArchiveUri, encodeArchiveBasePath, zipArchiveScheme } from '../archive-filesystem-provider';
 import { CodeQLCliServer } from '../cli';
 import { DatabaseManager } from '../databases';
-import { CachedOperation, ProgressCallback, withProgress } from '../helpers';
-import * as messages from '../pure/messages';
-import { QueryServerClient } from '../queryserver-client';
-import { compileAndRunQueryAgainstDatabase, QueryWithResults } from '../run-queries';
+import { CachedOperation } from '../helpers';
+import { ProgressCallback, withProgress } from '../commandRunner';
 import AstBuilder from './astBuilder';
 import {
   KeyType,
 } from './keyType';
 import { FullLocationLink, getLocationsForUriString, TEMPLATE_NAME } from './locationFinder';
 import { qlpackOfDatabase, resolveQueries } from './queryResolver';
+import { isCanary, NO_CACHE_AST_VIEWER } from '../config';
+import { createInitialQueryInfo, QueryWithResults } from '../run-queries-shared';
+import { QueryRunner } from '../queryRunner';
 
 /**
  * Run templated CodeQL queries to find definitions and references in
@@ -21,20 +33,21 @@ import { qlpackOfDatabase, resolveQueries } from './queryResolver';
  * or from a selected identifier.
  */
 
-export class TemplateQueryDefinitionProvider implements vscode.DefinitionProvider {
-  private cache: CachedOperation<vscode.LocationLink[]>;
+export class TemplateQueryDefinitionProvider implements DefinitionProvider {
+  private cache: CachedOperation<LocationLink[]>;
 
   constructor(
     private cli: CodeQLCliServer,
-    private qs: QueryServerClient,
+    private qs: QueryRunner,
     private dbm: DatabaseManager,
+    private queryStorageDir: string,
   ) {
-    this.cache = new CachedOperation<vscode.LocationLink[]>(this.getDefinitions.bind(this));
+    this.cache = new CachedOperation<LocationLink[]>(this.getDefinitions.bind(this));
   }
 
-  async provideDefinition(document: vscode.TextDocument, position: vscode.Position, _token: vscode.CancellationToken): Promise<vscode.LocationLink[]> {
+  async provideDefinition(document: TextDocument, position: Position, _token: CancellationToken): Promise<LocationLink[]> {
     const fileLinks = await this.cache.get(document.uri.toString());
-    const locLinks: vscode.LocationLink[] = [];
+    const locLinks: LocationLink[] = [];
     for (const link of fileLinks) {
       if (link.originSelectionRange!.contains(position)) {
         locLinks.push(link);
@@ -43,9 +56,9 @@ export class TemplateQueryDefinitionProvider implements vscode.DefinitionProvide
     return locLinks;
   }
 
-  private async getDefinitions(uriString: string): Promise<vscode.LocationLink[]> {
+  private async getDefinitions(uriString: string): Promise<LocationLink[]> {
     return withProgress({
-      location: vscode.ProgressLocation.Notification,
+      location: ProgressLocation.Notification,
       cancellable: true,
       title: 'Finding definitions'
     }, async (progress, token) => {
@@ -55,6 +68,7 @@ export class TemplateQueryDefinitionProvider implements vscode.DefinitionProvide
         this.dbm,
         uriString,
         KeyType.DefinitionQuery,
+        this.queryStorageDir,
         progress,
         token,
         (src, _dest) => src === uriString
@@ -63,25 +77,26 @@ export class TemplateQueryDefinitionProvider implements vscode.DefinitionProvide
   }
 }
 
-export class TemplateQueryReferenceProvider implements vscode.ReferenceProvider {
+export class TemplateQueryReferenceProvider implements ReferenceProvider {
   private cache: CachedOperation<FullLocationLink[]>;
 
   constructor(
     private cli: CodeQLCliServer,
-    private qs: QueryServerClient,
+    private qs: QueryRunner,
     private dbm: DatabaseManager,
+    private queryStorageDir: string,
   ) {
     this.cache = new CachedOperation<FullLocationLink[]>(this.getReferences.bind(this));
   }
 
   async provideReferences(
-    document: vscode.TextDocument,
-    position: vscode.Position,
-    _context: vscode.ReferenceContext,
-    _token: vscode.CancellationToken
-  ): Promise<vscode.Location[]> {
+    document: TextDocument,
+    position: Position,
+    _context: ReferenceContext,
+    _token: CancellationToken
+  ): Promise<Location[]> {
     const fileLinks = await this.cache.get(document.uri.toString());
-    const locLinks: vscode.Location[] = [];
+    const locLinks: Location[] = [];
     for (const link of fileLinks) {
       if (link.targetRange!.contains(position)) {
         locLinks.push({ range: link.originSelectionRange!, uri: link.originUri });
@@ -92,7 +107,7 @@ export class TemplateQueryReferenceProvider implements vscode.ReferenceProvider
 
   private async getReferences(uriString: string): Promise<FullLocationLink[]> {
     return withProgress({
-      location: vscode.ProgressLocation.Notification,
+      location: ProgressLocation.Notification,
       cancellable: true,
       title: 'Finding references'
     }, async (progress, token) => {
@@ -102,6 +117,7 @@ export class TemplateQueryReferenceProvider implements vscode.ReferenceProvider
         this.dbm,
         uriString,
         KeyType.DefinitionQuery,
+        this.queryStorageDir,
         progress,
         token,
         (src, _dest) => src === uriString
@@ -110,41 +126,123 @@ export class TemplateQueryReferenceProvider implements vscode.ReferenceProvider
   }
 }
 
+type QueryWithDb = {
+  query: QueryWithResults,
+  dbUri: Uri
+};
+
 export class TemplatePrintAstProvider {
-  private cache: CachedOperation<QueryWithResults | undefined>;
+  private cache: CachedOperation<QueryWithDb>;
 
   constructor(
     private cli: CodeQLCliServer,
-    private qs: QueryServerClient,
+    private qs: QueryRunner,
     private dbm: DatabaseManager,
-
-    // Note: progress and token are only used if a cached value is not available
-    private progress: ProgressCallback,
-    private token: vscode.CancellationToken
+    private queryStorageDir: string,
   ) {
-    this.cache = new CachedOperation<QueryWithResults | undefined>(this.getAst.bind(this));
+    this.cache = new CachedOperation<QueryWithDb>(this.getAst.bind(this));
   }
 
-  async provideAst(document?: vscode.TextDocument): Promise<AstBuilder | undefined> {
-    if (!document) {
-      return;
-    }
-    const queryResults = await this.cache.get(document.uri.toString());
-    if (!queryResults) {
-      return;
+  async provideAst(
+    progress: ProgressCallback,
+    token: CancellationToken,
+    fileUri?: Uri
+  ): Promise<AstBuilder | undefined> {
+    if (!fileUri) {
+      throw new Error('Cannot view the AST. Please select a valid source file inside a CodeQL database.');
     }
+    const { query, dbUri } = this.shouldCache()
+      ? await this.cache.get(fileUri.toString(), progress, token)
+      : await this.getAst(fileUri.toString(), progress, token);
 
     return new AstBuilder(
-      queryResults, this.cli,
-      this.dbm.findDatabaseItem(vscode.Uri.parse(queryResults.database.databaseUri!, true))!,
-      document.fileName
+      query, this.cli,
+      this.dbm.findDatabaseItem(dbUri)!,
+      fileUri,
     );
   }
 
-  private async getAst(uriString: string): Promise<QueryWithResults> {
-    const uri = vscode.Uri.parse(uriString, true);
+  private shouldCache() {
+    return !(isCanary() && NO_CACHE_AST_VIEWER.getValue<boolean>());
+  }
+
+  private async getAst(
+    uriString: string,
+    progress: ProgressCallback,
+    token: CancellationToken
+  ): Promise<QueryWithDb> {
+    const uri = Uri.parse(uriString, true);
     if (uri.scheme !== zipArchiveScheme) {
-      throw new Error('AST Viewing is only available for databases with zipped source archives.');
+      throw new Error('Cannot view the AST. Please select a valid source file inside a CodeQL database.');
+    }
+
+    const zippedArchive = decodeSourceArchiveUri(uri);
+    const sourceArchiveUri = encodeArchiveBasePath(zippedArchive.sourceArchiveZipPath);
+    const db = this.dbm.findDatabaseItemBySourceArchive(sourceArchiveUri);
+
+    if (!db) {
+      throw new Error('Can\'t infer database from the provided source.');
+    }
+
+    const qlpacks = await qlpackOfDatabase(this.cli, db);
+    const queries = await resolveQueries(this.cli, qlpacks, KeyType.PrintAstQuery);
+    if (queries.length > 1) {
+      throw new Error('Found multiple Print AST queries. Can\'t continue');
+    }
+    if (queries.length === 0) {
+      throw new Error('Did not find any Print AST queries. Can\'t continue');
+    }
+
+    const query = queries[0];
+    const templates: Record<string, string> = {
+      [TEMPLATE_NAME]:
+        zippedArchive.pathWithinSourceArchive
+    };
+
+    const initialInfo = await createInitialQueryInfo(
+      Uri.file(query),
+      {
+        name: db.name,
+        databaseUri: db.databaseUri.toString(),
+      },
+      false
+    );
+
+    return {
+      query: await this.qs.compileAndRunQueryAgainstDatabase(
+        db,
+        initialInfo,
+        this.queryStorageDir,
+        progress,
+        token,
+        templates
+      ),
+      dbUri: db.databaseUri
+    };
+  }
+}
+
+export class TemplatePrintCfgProvider {
+  private cache: CachedOperation<[Uri, Record<string, string>] | undefined>;
+
+  constructor(
+    private cli: CodeQLCliServer,
+    private dbm: DatabaseManager,
+  ) {
+    this.cache = new CachedOperation<[Uri, Record<string, string>] | undefined>(this.getCfgUri.bind(this));
+  }
+
+  async provideCfgUri(document?: TextDocument): Promise<[Uri, Record<string, string>] | undefined> {
+    if (!document) {
+      return;
+    }
+    return await this.cache.get(document.uri.toString());
+  }
+
+  private async getCfgUri(uriString: string): Promise<[Uri, Record<string, string>]> {
+    const uri = Uri.parse(uriString, true);
+    if (uri.scheme !== zipArchiveScheme) {
+      throw new Error('CFG Viewing is only available for databases with zipped source archives.');
     }
 
     const zippedArchive = decodeSourceArchiveUri(uri);
@@ -157,36 +255,22 @@ export class TemplatePrintAstProvider {
 
     const qlpack = await qlpackOfDatabase(this.cli, db);
     if (!qlpack) {
-      throw new Error('Can\'t infer qlpack from database source archive');
+      throw new Error('Can\'t infer qlpack from database source archive.');
     }
-    const queries = await resolveQueries(this.cli, qlpack, KeyType.PrintAstQuery);
+    const queries = await resolveQueries(this.cli, qlpack, KeyType.PrintCfgQuery);
     if (queries.length > 1) {
-      throw new Error('Found multiple Print AST queries. Can\'t continue');
+      throw new Error(`Found multiple Print CFG queries. Can't continue. Make sure there is exacly one query with the tag ${KeyType.PrintCfgQuery}`);
     }
     if (queries.length === 0) {
-      throw new Error('Did not find any Print AST queries. Can\'t continue');
+      throw new Error(`Did not find any Print CFG queries. Can't continue. Make sure there is exacly one query with the tag ${KeyType.PrintCfgQuery}`);
     }
 
-    const query = queries[0];
-    const templates: messages.TemplateDefinitions = {
-      [TEMPLATE_NAME]: {
-        values: {
-          tuples: [[{
-            stringValue: zippedArchive.pathWithinSourceArchive
-          }]]
-        }
-      }
+    const queryUri = Uri.file(queries[0]);
+
+    const templates: Record<string, string> = {
+      [TEMPLATE_NAME]: zippedArchive.pathWithinSourceArchive
     };
 
-    return await compileAndRunQueryAgainstDatabase(
-      this.cli,
-      this.qs,
-      db,
-      false,
-      vscode.Uri.file(query),
-      this.progress,
-      this.token,
-      templates
-    );
+    return [queryUri, templates];
   }
 }

extensions/ql-vscode/src/databaseFetcher.ts

@@ -1,33 +1,43 @@
 import fetch, { Response } from 'node-fetch';
-import * as unzipper from 'unzipper';
 import { zip } from 'zip-a-folder';
+import * as unzipper from 'unzipper';
 import {
   Uri,
   CancellationToken,
   commands,
   window,
 } from 'vscode';
+import { CodeQLCliServer } from './cli';
 import * as fs from 'fs-extra';
 import * as path from 'path';
+import * as Octokit from '@octokit/rest';
+import { retry } from '@octokit/plugin-retry';
 
 import { DatabaseManager, DatabaseItem } from './databases';
 import {
-  ProgressCallback,
   showAndLogInformationMessage,
 } from './helpers';
+import {
+  reportStreamProgress,
+  ProgressCallback,
+} from './commandRunner';
 import { logger } from './logging';
+import { tmpDir } from './helpers';
+import { Credentials } from './authentication';
+import { REPO_REGEX, getErrorMessage } from './pure/helpers-pure';
 
 /**
  * Prompts a user to fetch a database from a remote location. Database is assumed to be an archive file.
  *
- * @param databasesManager the DatabaseManager
+ * @param databaseManager the DatabaseManager
  * @param storagePath where to store the unzipped database.
  */
 export async function promptImportInternetDatabase(
-  databasesManager: DatabaseManager,
+  databaseManager: DatabaseManager,
   storagePath: string,
   progress: ProgressCallback,
-  _: CancellationToken,
+  token: CancellationToken,
+  cli?: CodeQLCliServer
 ): Promise<DatabaseItem | undefined> {
   const databaseUrl = await window.showInputBox({
     prompt: 'Enter URL of zipfile of database to download',
@@ -40,53 +50,139 @@ export async function promptImportInternetDatabase(
 
   const item = await databaseArchiveFetcher(
     databaseUrl,
-    databasesManager,
+    {},
+    databaseManager,
     storagePath,
-    progress
+    undefined,
+    progress,
+    token,
+    cli
   );
 
   if (item) {
-    commands.executeCommand('codeQLDatabases.focus');
-    showAndLogInformationMessage('Database downloaded and imported successfully.');
+    await commands.executeCommand('codeQLDatabases.focus');
+    void showAndLogInformationMessage('Database downloaded and imported successfully.');
   }
   return item;
 
 }
 
+/**
+ * Prompts a user to fetch a database from GitHub.
+ * User enters a GitHub repository and then the user is asked which language
+ * to download (if there is more than one)
+ *
+ * @param databaseManager the DatabaseManager
+ * @param storagePath where to store the unzipped database.
+ */
+export async function promptImportGithubDatabase(
+  databaseManager: DatabaseManager,
+  storagePath: string,
+  credentials: Credentials | undefined,
+  progress: ProgressCallback,
+  token: CancellationToken,
+  cli?: CodeQLCliServer
+): Promise<DatabaseItem | undefined> {
+  progress({
+    message: 'Choose repository',
+    step: 1,
+    maxStep: 2
+  });
+  const githubRepo = await window.showInputBox({
+    title: 'Enter a GitHub repository URL or "name with owner" (e.g. https://github.com/github/codeql or github/codeql)',
+    placeHolder: 'https://github.com/<owner>/<repo> or <owner>/<repo>',
+    ignoreFocusOut: true,
+  });
+  if (!githubRepo) {
+    return;
+  }
+
+  if (!looksLikeGithubRepo(githubRepo)) {
+    throw new Error(`Invalid GitHub repository: ${githubRepo}`);
+  }
+
+  const octokit = credentials ? await credentials.getOctokit(true) : new Octokit.Octokit({ retry });
+
+  const result = await convertGithubNwoToDatabaseUrl(githubRepo, octokit, progress);
+  if (!result) {
+    return;
+  }
+
+  const { databaseUrl, name, owner } = result;
+
+  /**
+   * The 'token' property of the token object returned by `octokit.auth()`.
+   * The object is undocumented, but looks something like this:
+   * {
+   *   token: 'xxxx',
+   *   tokenType: 'oauth',
+   *   type: 'token',
+   * }
+   * We only need the actual token string.
+   */
+  const octokitToken = (await octokit.auth() as { token: string })?.token;
+  const item = await databaseArchiveFetcher(
+    databaseUrl,
+    { 'Accept': 'application/zip', 'Authorization': octokitToken ? `Bearer ${octokitToken}` : '' },
+    databaseManager,
+    storagePath,
+    `${owner}/${name}`,
+    progress,
+    token,
+    cli
+  );
+  if (item) {
+    await commands.executeCommand('codeQLDatabases.focus');
+    void showAndLogInformationMessage('Database downloaded and imported successfully.');
+    return item;
+  }
+  return;
+}
+
 /**
  * Prompts a user to fetch a database from lgtm.
  * User enters a project url and then the user is asked which language
  * to download (if there is more than one)
  *
- * @param databasesManager the DatabaseManager
+ * @param databaseManager the DatabaseManager
  * @param storagePath where to store the unzipped database.
  */
 export async function promptImportLgtmDatabase(
-  databasesManager: DatabaseManager,
+  databaseManager: DatabaseManager,
   storagePath: string,
   progress: ProgressCallback,
-  _: CancellationToken
+  token: CancellationToken,
+  cli?: CodeQLCliServer
 ): Promise<DatabaseItem | undefined> {
+  progress({
+    message: 'Choose project',
+    step: 1,
+    maxStep: 2
+  });
   const lgtmUrl = await window.showInputBox({
     prompt:
-      'Enter the project URL on LGTM (e.g., https://lgtm.com/projects/g/github/codeql)',
+      'Enter the project slug or URL on LGTM (e.g., g/github/codeql or https://lgtm.com/projects/g/github/codeql)',
   });
   if (!lgtmUrl) {
     return;
   }
 
   if (looksLikeLgtmUrl(lgtmUrl)) {
-    const databaseUrl = await convertToDatabaseUrl(lgtmUrl);
+    const databaseUrl = await convertLgtmUrlToDatabaseUrl(lgtmUrl, progress);
     if (databaseUrl) {
       const item = await databaseArchiveFetcher(
         databaseUrl,
-        databasesManager,
+        {},
+        databaseManager,
         storagePath,
-        progress
+        undefined,
+        progress,
+        token,
+        cli
       );
       if (item) {
-        commands.executeCommand('codeQLDatabases.focus');
-        showAndLogInformationMessage('Database downloaded and imported successfully.');
+        await commands.executeCommand('codeQLDatabases.focus');
+        void showAndLogInformationMessage('Database downloaded and imported successfully.');
       }
       return item;
     }
@@ -96,34 +192,49 @@ export async function promptImportLgtmDatabase(
   return;
 }
 
+export async function retrieveCanonicalRepoName(lgtmUrl: string) {
+  const givenRepoName = extractProjectSlug(lgtmUrl);
+  const response = await checkForFailingResponse(await fetch(`https://api.github.com/repos/${givenRepoName}`), 'Failed to locate the repository on github');
+  const repo = await response.json();
+  if (!repo || !repo.full_name) {
+    return;
+  }
+  return repo.full_name;
+}
+
 /**
  * Imports a database from a local archive.
  *
  * @param databaseUrl the file url of the archive to import
- * @param databasesManager the DatabaseManager
+ * @param databaseManager the DatabaseManager
  * @param storagePath where to store the unzipped database.
  */
 export async function importArchiveDatabase(
   databaseUrl: string,
-  databasesManager: DatabaseManager,
+  databaseManager: DatabaseManager,
   storagePath: string,
   progress: ProgressCallback,
-  _: CancellationToken,
+  token: CancellationToken,
+  cli?: CodeQLCliServer,
 ): Promise<DatabaseItem | undefined> {
   try {
     const item = await databaseArchiveFetcher(
       databaseUrl,
-      databasesManager,
+      {},
+      databaseManager,
       storagePath,
-      progress
+      undefined,
+      progress,
+      token,
+      cli
     );
     if (item) {
-      commands.executeCommand('codeQLDatabases.focus');
-      showAndLogInformationMessage('Database unzipped and imported successfully.');
+      await commands.executeCommand('codeQLDatabases.focus');
+      void showAndLogInformationMessage('Database unzipped and imported successfully.');
     }
     return item;
   } catch (e) {
-    if (e.message.includes('unexpected end of file')) {
+    if (getErrorMessage(e).includes('unexpected end of file')) {
       throw new Error('Database is corrupt or too large. Try unzipping outside of VS Code and importing the unzipped folder instead.');
     } else {
       // delegate
@@ -137,17 +248,24 @@ export async function importArchiveDatabase(
  * or in the local filesystem.
  *
  * @param databaseUrl URL from which to grab the database
- * @param databasesManager the DatabaseManager
+ * @param requestHeaders Headers to send with the request
+ * @param databaseManager the DatabaseManager
  * @param storagePath where to store the unzipped database.
- * @param progressCallback optional callback to send progress messages to
+ * @param nameOverride a name for the database that overrides the default
+ * @param progress callback to send progress messages to
+ * @param token cancellation token
  */
 async function databaseArchiveFetcher(
   databaseUrl: string,
-  databasesManager: DatabaseManager,
+  requestHeaders: { [key: string]: string },
+  databaseManager: DatabaseManager,
   storagePath: string,
-  progressCallback?: ProgressCallback
+  nameOverride: string | undefined,
+  progress: ProgressCallback,
+  token: CancellationToken,
+  cli?: CodeQLCliServer,
 ): Promise<DatabaseItem> {
-  progressCallback?.({
+  progress({
     message: 'Getting database',
     step: 1,
     maxStep: 4,
@@ -159,12 +277,12 @@ async function databaseArchiveFetcher(
   const unzipPath = await getStorageFolder(storagePath, databaseUrl);
 
   if (isFile(databaseUrl)) {
-    await readAndUnzip(databaseUrl, unzipPath);
+    await readAndUnzip(databaseUrl, unzipPath, cli, progress);
   } else {
-    await fetchAndUnzip(databaseUrl, unzipPath, progressCallback);
+    await fetchAndUnzip(databaseUrl, requestHeaders, unzipPath, cli, progress);
   }
 
-  progressCallback?.({
+  progress({
     message: 'Opening database',
     step: 3,
     maxStep: 4,
@@ -177,15 +295,15 @@ async function databaseArchiveFetcher(
     'codeql-database.yml'
   );
   if (dbPath) {
-    progressCallback?.({
+    progress({
       message: 'Validating and fixing source location',
       step: 4,
       maxStep: 4,
     });
     await ensureZippedSourceLocation(dbPath);
 
-    const item = await databasesManager.openDatabase(Uri.file(dbPath));
-    databasesManager.setCurrentDatabaseItem(item);
+    const item = await databaseManager.openDatabase(progress, token, Uri.file(dbPath), nameOverride);
+    await databaseManager.setCurrentDatabaseItem(item);
     return item;
   } else {
     throw new Error('Database not found in archive.');
@@ -232,48 +350,78 @@ function validateHttpsUrl(databaseUrl: string) {
   }
 }
 
-async function readAndUnzip(databaseUrl: string, unzipPath: string) {
-  const databaseFile = Uri.parse(databaseUrl).fsPath;
-  const directory = await unzipper.Open.file(databaseFile);
-  await directory.extract({ path: unzipPath });
+async function readAndUnzip(
+  zipUrl: string,
+  unzipPath: string,
+  cli?: CodeQLCliServer,
+  progress?: ProgressCallback
+) {
+  // TODO: Providing progress as the file is unzipped is currently blocked
+  // on https://github.com/ZJONSSON/node-unzipper/issues/222
+  const zipFile = Uri.parse(zipUrl).fsPath;
+  progress?.({
+    maxStep: 10,
+    step: 9,
+    message: `Unzipping into ${path.basename(unzipPath)}`
+  });
+  if (cli && await cli.cliConstraints.supportsDatabaseUnbundle()) {
+    // Use the `database unbundle` command if the installed cli version supports it
+    await cli.databaseUnbundle(zipFile, unzipPath);
+  } else {
+    // Must get the zip central directory since streaming the
+    // zip contents may not have correct local file headers.
+    // Instead, we can only rely on the central directory.
+    const directory = await unzipper.Open.file(zipFile);
+    await directory.extract({ path: unzipPath });
+  }
 }
 
 async function fetchAndUnzip(
   databaseUrl: string,
+  requestHeaders: { [key: string]: string },
   unzipPath: string,
-  progressCallback?: ProgressCallback
+  cli?: CodeQLCliServer,
+  progress?: ProgressCallback
 ) {
-  const response = await fetch(databaseUrl);
+  // Although it is possible to download and stream directly to an unzipped directory,
+  // we need to avoid this for two reasons. The central directory is located at the
+  // end of the zip file. It is the source of truth of the content locations. Individual
+  // file headers may be incorrect. Additionally, saving to file first will reduce memory
+  // pressure compared with unzipping while downloading the archive.
 
-  await checkForFailingResponse(response);
+  const archivePath = path.join(tmpDir.name, `archive-${Date.now()}.zip`);
 
-  const unzipStream = unzipper.Extract({
-    path: unzipPath,
-  });
-
-  progressCallback?.({
+  progress?.({
     maxStep: 3,
-    message: 'Unzipping database',
-    step: 2,
-  });
-  await new Promise((resolve, reject) => {
-    const handler = (err: Error) => {
-      if (err.message.startsWith('invalid signature')) {
-        reject(new Error('Not a valid archive.'));
-      } else {
-        reject(err);
-      }
-    };
-    response.body.on('error', handler);
-    unzipStream.on('error', handler);
-    unzipStream.on('close', resolve);
-    response.body.pipe(unzipStream);
+    message: 'Downloading database',
+    step: 1,
   });
+
+  const response = await checkForFailingResponse(
+    await fetch(databaseUrl, { headers: requestHeaders }),
+    'Error downloading database'
+  );
+  const archiveFileStream = fs.createWriteStream(archivePath);
+
+  const contentLength = response.headers.get('content-length');
+  const totalNumBytes = contentLength ? parseInt(contentLength, 10) : undefined;
+  reportStreamProgress(response.body, 'Downloading database', totalNumBytes, progress);
+
+  await new Promise((resolve, reject) =>
+    response.body.pipe(archiveFileStream)
+      .on('finish', resolve)
+      .on('error', reject)
+  );
+
+  await readAndUnzip(Uri.file(archivePath).toString(true), unzipPath, cli, progress);
+
+  // remove archivePath eagerly since these archives can be large.
+  await fs.remove(archivePath);
 }
 
-async function checkForFailingResponse(response: Response): Promise<void | never> {
+async function checkForFailingResponse(response: Response, errorMessage: string): Promise<Response | never> {
   if (response.ok) {
-    return;
+    return response;
   }
 
   // An error downloading the database. Attempt to extract the resaon behind it.
@@ -285,7 +433,7 @@ async function checkForFailingResponse(response: Response): Promise<void | never
   } catch (e) {
     msg = text;
   }
-  throw new Error(`Error downloading database.\n\nReason: ${msg}`);
+  throw new Error(`${errorMessage}.\n\nReason: ${msg}`);
 }
 
 function isFile(databaseUrl: string) {
@@ -322,15 +470,98 @@ export async function findDirWithFile(
   return;
 }
 
+/**
+ * The URL pattern is https://github.com/{owner}/{name}/{subpages}.
+ *
+ * This function accepts any URL that matches the pattern above. It also accepts just the
+ * name with owner (NWO): `<owner>/<repo>`.
+ *
+ * @param githubRepo The GitHub repository URL or NWO
+ *
+ * @return true if this looks like a valid GitHub repository URL or NWO
+ */
+export function looksLikeGithubRepo(
+  githubRepo: string | undefined
+): githubRepo is string {
+  if (!githubRepo) {
+    return false;
+  }
+  if (REPO_REGEX.test(githubRepo) || convertGitHubUrlToNwo(githubRepo)) {
+    return true;
+  }
+  return false;
+}
+
+/**
+ * Converts a GitHub repository URL to the corresponding NWO.
+ * @param githubUrl The GitHub repository URL
+ * @return The corresponding NWO, or undefined if the URL is not valid
+ */
+function convertGitHubUrlToNwo(githubUrl: string): string | undefined {
+  try {
+    const uri = Uri.parse(githubUrl, true);
+    if (uri.scheme !== 'https') {
+      return;
+    }
+    if (uri.authority !== 'github.com' && uri.authority !== 'www.github.com') {
+      return;
+    }
+    const paths = uri.path.split('/').filter((segment: string) => segment);
+    const nwo = `${paths[0]}/${paths[1]}`;
+    if (REPO_REGEX.test(nwo)) {
+      return nwo;
+    }
+    return;
+  } catch (e) {
+    // Ignore the error here, since we catch failures at a higher level.
+    // In particular: returning undefined leads to an error in 'promptImportGithubDatabase'.
+    return;
+  }
+}
+
+export async function convertGithubNwoToDatabaseUrl(
+  githubRepo: string,
+  octokit: Octokit.Octokit,
+  progress: ProgressCallback): Promise<{
+    databaseUrl: string,
+    owner: string,
+    name: string
+  } | undefined> {
+  try {
+    const nwo = convertGitHubUrlToNwo(githubRepo) || githubRepo;
+    const [owner, repo] = nwo.split('/');
+
+    const response = await octokit.request('GET /repos/:owner/:repo/code-scanning/codeql/databases', { owner, repo });
+
+    const languages = response.data.map((db: any) => db.language);
+
+    const language = await promptForLanguage(languages, progress);
+    if (!language) {
+      return;
+    }
+
+    return {
+      databaseUrl: `https://api.github.com/repos/${owner}/${repo}/code-scanning/codeql/databases/${language}`,
+      owner,
+      name: repo
+    };
+
+  } catch (e) {
+    void logger.log(`Error: ${getErrorMessage(e)}`);
+    throw new Error(`Unable to get database for '${githubRepo}'`);
+  }
+}
+
 /**
  * The URL pattern is https://lgtm.com/projects/{provider}/{org}/{name}/{irrelevant-subpages}.
- * There are several possibilities for the provider: in addition to GitHub.com(g),
+ * There are several possibilities for the provider: in addition to GitHub.com (g),
  * LGTM currently hosts projects from Bitbucket (b), GitLab (gl) and plain git (git).
  *
- * After the {provider}/{org}/{name} path components, there may be the components
- * related to sub pages.
+ * This function accepts any url that matches the pattern above. It also accepts the
+ * raw project slug, e.g., `g/myorg/myproject`
  *
- * This function accepts any url that matches the patter above
+ * After the `{provider}/{org}/{name}` path components, there may be the components
+ * related to sub pages.
  *
  * @param lgtmUrl The URL to the lgtm project
  *
@@ -342,6 +573,10 @@ export function looksLikeLgtmUrl(lgtmUrl: string | undefined): lgtmUrl is string
     return false;
   }
 
+  if (convertRawLgtmSlug(lgtmUrl)) {
+    return true;
+  }
+
   try {
     const uri = Uri.parse(lgtmUrl, true);
     if (uri.scheme !== 'https') {
@@ -352,29 +587,60 @@ export function looksLikeLgtmUrl(lgtmUrl: string | undefined): lgtmUrl is string
       return false;
     }
 
-    const paths = uri.path.split('/').filter((segment) => segment);
+    const paths = uri.path.split('/').filter((segment: string) => segment);
     return paths.length >= 4 && paths[0] === 'projects';
   } catch (e) {
     return false;
   }
 }
 
+function convertRawLgtmSlug(maybeSlug: string): string | undefined {
+  if (!maybeSlug) {
+    return;
+  }
+  const segments = maybeSlug.split('/');
+  const providers = ['g', 'gl', 'b', 'git'];
+  if (segments.length === 3 && providers.includes(segments[0])) {
+    return `https://lgtm.com/projects/${maybeSlug}`;
+  }
+  return;
+}
+
+function extractProjectSlug(lgtmUrl: string): string | undefined {
+  // Only matches the '/g/' provider (github)
+  const re = new RegExp('https://lgtm.com/projects/g/(.*[^/])');
+  const match = lgtmUrl.match(re);
+  if (!match) {
+    return;
+  }
+  return match[1];
+}
+
 // exported for testing
-export async function convertToDatabaseUrl(lgtmUrl: string) {
+export async function convertLgtmUrlToDatabaseUrl(
+  lgtmUrl: string,
+  progress: ProgressCallback) {
   try {
-    const uri = Uri.parse(lgtmUrl, true);
-    const paths = ['api', 'v1.0'].concat(
-      uri.path.split('/').filter((segment) => segment)
-    ).slice(0, 6);
-    const projectUrl = `https://lgtm.com/${paths.join('/')}`;
-    const projectResponse = await fetch(projectUrl);
-    const projectJson = await projectResponse.json();
+    lgtmUrl = convertRawLgtmSlug(lgtmUrl) || lgtmUrl;
+    let projectJson = await downloadLgtmProjectMetadata(lgtmUrl);
 
     if (projectJson.code === 404) {
-      throw new Error();
+      // fallback check for github repositories with same name but different case
+      // will fail for other providers
+      let canonicalName = await retrieveCanonicalRepoName(lgtmUrl);
+      if (!canonicalName) {
+        throw new Error(`Project was not found at ${lgtmUrl}.`);
+      }
+      canonicalName = convertRawLgtmSlug(`g/${canonicalName}`);
+      projectJson = await downloadLgtmProjectMetadata(canonicalName);
+      if (projectJson.code === 404) {
+        throw new Error('Failed to download project from LGTM.');
+      }
     }
 
-    const language = await promptForLanguage(projectJson);
+    const languages = projectJson?.languages?.map((lang: { language: string }) => lang.language) || [];
+
+    const language = await promptForLanguage(languages, progress);
     if (!language) {
       return;
     }
@@ -386,25 +652,43 @@ export async function convertToDatabaseUrl(lgtmUrl: string) {
       language,
     ].join('/')}`;
   } catch (e) {
-    logger.log(`Error: ${e.message}`);
+    void logger.log(`Error: ${getErrorMessage(e)}`);
     throw new Error(`Invalid LGTM URL: ${lgtmUrl}`);
   }
 }
 
+async function downloadLgtmProjectMetadata(lgtmUrl: string): Promise<any> {
+  const uri = Uri.parse(lgtmUrl, true);
+  const paths = ['api', 'v1.0'].concat(
+    uri.path.split('/').filter((segment: string) => segment)
+  ).slice(0, 6);
+  const projectUrl = `https://lgtm.com/${paths.join('/')}`;
+  const projectResponse = await fetch(projectUrl);
+  return projectResponse.json();
+}
+
 async function promptForLanguage(
-  projectJson: any
+  languages: string[],
+  progress: ProgressCallback
 ): Promise<string | undefined> {
-  if (!projectJson?.languages?.length) {
-    return;
+  progress({
+    message: 'Choose language',
+    step: 2,
+    maxStep: 2
+  });
+  if (!languages.length) {
+    throw new Error('No databases found');
   }
-  if (projectJson.languages.length === 1) {
-    return projectJson.languages[0].language;
+  if (languages.length === 1) {
+    return languages[0];
   }
 
   return await window.showQuickPick(
-    projectJson.languages.map((lang: { language: string }) => lang.language), {
-    placeHolder: 'Select the database language to download:'
-  }
+    languages,
+    {
+      placeHolder: 'Select the database language to download:',
+      ignoreFocusOut: true,
+    }
   );
 }
 

extensions/ql-vscode/src/databases-ui.ts

@@ -1,5 +1,5 @@
 import * as path from 'path';
-import { DisposableObject } from './vscode-utils/disposable-object';
+import { DisposableObject } from './pure/disposable-object';
 import {
   Event,
   EventEmitter,
@@ -12,33 +12,33 @@ import {
 } from 'vscode';
 import * as fs from 'fs-extra';
 
-import * as cli from './cli';
 import {
   DatabaseChangedEvent,
   DatabaseItem,
   DatabaseManager,
-  getUpgradesDirectories,
-  isLikelyDatabaseRoot,
-  isLikelyDbLanguageFolder,
 } from './databases';
 import {
   commandRunner,
   commandRunnerWithProgress,
-  getOnDiskWorkspaceFolders,
   ProgressCallback,
+} from './commandRunner';
+import {
+  isLikelyDatabaseRoot,
+  isLikelyDbLanguageFolder,
   showAndLogErrorMessage
 } from './helpers';
 import { logger } from './logging';
-import { clearCacheInDatabase } from './run-queries';
-import * as qsClient from './queryserver-client';
-import { upgradeDatabase } from './upgrades';
 import {
   importArchiveDatabase,
+  promptImportGithubDatabase,
   promptImportInternetDatabase,
   promptImportLgtmDatabase,
 } from './databaseFetcher';
 import { CancellationToken } from 'vscode';
-import { asyncFilter } from './pure/helpers-pure';
+import { asyncFilter, getErrorMessage } from './pure/helpers-pure';
+import { Credentials } from './authentication';
+import { QueryRunner } from './queryRunner';
+import { isCanary } from './config';
 
 type ThemableIconPath = { light: string; dark: string } | string;
 
@@ -81,7 +81,7 @@ class DatabaseTreeDataProvider extends DisposableObject
   implements TreeDataProvider<DatabaseItem> {
   private _sortOrder = SortOrder.NameAsc;
 
-  private readonly _onDidChangeTreeData = new EventEmitter<DatabaseItem | undefined>();
+  private readonly _onDidChangeTreeData = this.push(new EventEmitter<DatabaseItem | undefined>());
   private currentDatabaseItem: DatabaseItem | undefined;
 
   constructor(
@@ -109,7 +109,7 @@ class DatabaseTreeDataProvider extends DisposableObject
   }
 
   private handleDidChangeDatabaseItem = (event: DatabaseChangedEvent): void => {
-    // Note that events from the databse manager are instances of DatabaseChangedEvent
+    // Note that events from the database manager are instances of DatabaseChangedEvent
     // and events fired by the UI are instances of DatabaseItem
 
     // When event.item is undefined, then the entire tree is refreshed.
@@ -136,6 +136,7 @@ class DatabaseTreeDataProvider extends DisposableObject
         this.extensionPath,
         SELECTED_DATABASE_ICON
       );
+      item.contextValue = 'currentDatabase';
     } else if (element.error !== undefined) {
       item.iconPath = joinThemableIconPath(
         this.extensionPath,
@@ -143,6 +144,7 @@ class DatabaseTreeDataProvider extends DisposableObject
       );
     }
     item.tooltip = element.databaseUri.fsPath;
+    item.description = element.language;
     return item;
   }
 
@@ -179,7 +181,7 @@ class DatabaseTreeDataProvider extends DisposableObject
 
   public set sortOrder(newSortOrder: SortOrder) {
     this._sortOrder = newSortOrder;
-    this._onDidChangeTreeData.fire();
+    this._onDidChangeTreeData.fire(undefined);
   }
 }
 
@@ -215,11 +217,11 @@ export class DatabaseUI extends DisposableObject {
   private treeDataProvider: DatabaseTreeDataProvider;
 
   public constructor(
-    private cliserver: cli.CodeQLCliServer,
     private databaseManager: DatabaseManager,
-    private readonly queryServer: qsClient.QueryServerClient | undefined,
+    private readonly queryServer: QueryRunner | undefined,
     private readonly storagePath: string,
-    readonly extensionPath: string
+    readonly extensionPath: string,
+    private readonly getCredentials: () => Promise<Credentials>
   ) {
     super();
 
@@ -235,7 +237,7 @@ export class DatabaseUI extends DisposableObject {
   }
 
   init() {
-    logger.log('Registering database panel commands.');
+    void logger.log('Registering database panel commands.');
     this.push(
       commandRunnerWithProgress(
         'codeQL.setCurrentDatabase',
@@ -291,6 +293,20 @@ export class DatabaseUI extends DisposableObject {
         }
       )
     );
+    this.push(
+      commandRunnerWithProgress(
+        'codeQLDatabases.chooseDatabaseGithub',
+        async (
+          progress: ProgressCallback,
+          token: CancellationToken
+        ) => {
+          const credentials = isCanary() ? await this.getCredentials() : undefined;
+          await this.handleChooseDatabaseGithub(credentials, progress, token);
+        },
+        {
+          title: 'Adding database from GitHub',
+        })
+    );
     this.push(
       commandRunnerWithProgress(
         'codeQLDatabases.chooseDatabaseLgtm',
@@ -318,9 +334,13 @@ export class DatabaseUI extends DisposableObject {
       )
     );
     this.push(
-      commandRunner(
+      commandRunnerWithProgress(
         'codeQLDatabases.removeDatabase',
-        this.handleRemoveDatabase
+        this.handleRemoveDatabase,
+        {
+          title: 'Removing database',
+          cancellable: false
+        }
       )
     );
     this.push(
@@ -345,6 +365,12 @@ export class DatabaseUI extends DisposableObject {
         this.handleOpenFolder
       )
     );
+    this.push(
+      commandRunner(
+        'codeQLDatabases.addDatabaseSource',
+        this.handleAddSource
+      )
+    );
     this.push(
       commandRunner(
         'codeQLDatabases.removeOrphanedDatabases',
@@ -362,18 +388,27 @@ export class DatabaseUI extends DisposableObject {
   handleChooseDatabaseFolder = async (
     progress: ProgressCallback,
     token: CancellationToken
-  ): Promise<DatabaseItem | undefined> => {
+  ): Promise<void> => {
     try {
-      return await this.chooseAndSetDatabase(true, progress, token);
+      await this.chooseAndSetDatabase(true, progress, token);
     } catch (e) {
-      showAndLogErrorMessage(e.message);
-      return undefined;
+      void showAndLogErrorMessage(getErrorMessage(e));
     }
   };
 
   handleRemoveOrphanedDatabases = async (): Promise<void> => {
-    logger.log('Removing orphaned databases from workspace storage.');
-    let dbDirs =
+    void logger.log('Removing orphaned databases from workspace storage.');
+    let dbDirs = undefined;
+
+    if (
+      !(await fs.pathExists(this.storagePath)) ||
+      !(await fs.stat(this.storagePath)).isDirectory()
+    ) {
+      void logger.log('Missing or invalid storage directory. Not trying to remove orphaned databases.');
+      return;
+    }
+
+    dbDirs =
       // read directory
       (await fs.readdir(this.storagePath, { withFileTypes: true }))
         // remove non-directories
@@ -390,7 +425,7 @@ export class DatabaseUI extends DisposableObject {
     dbDirs = await asyncFilter(dbDirs, isLikelyDatabaseRoot);
 
     if (!dbDirs.length) {
-      logger.log('No orphaned databases found.');
+      void logger.log('No orphaned databases found.');
       return;
     }
 
@@ -399,8 +434,8 @@ export class DatabaseUI extends DisposableObject {
     await Promise.all(
       dbDirs.map(async dbDir => {
         try {
-          logger.log(`Deleting orphaned database '${dbDir}'.`);
-          await fs.rmdir(dbDir, { recursive: true } as any);  // typings doesn't recognize the options argument
+          void logger.log(`Deleting orphaned database '${dbDir}'.`);
+          await fs.remove(dbDir);
         } catch (e) {
           failures.push(`${path.basename(dbDir)}`);
         }
@@ -409,10 +444,9 @@ export class DatabaseUI extends DisposableObject {
 
     if (failures.length) {
       const dirname = path.dirname(failures[0]);
-      showAndLogErrorMessage(
-        `Failed to delete unused databases:\n  ${
-        failures.join('\n  ')
-        }\n. To delete unused databases, please remove them manually from the storage folder ${dirname}.`
+      void showAndLogErrorMessage(
+        `Failed to delete unused databases (${failures.join(', ')
+        }).\nTo delete unused databases, please remove them manually from the storage folder ${dirname}.`
       );
     }
   };
@@ -421,26 +455,39 @@ export class DatabaseUI extends DisposableObject {
   handleChooseDatabaseArchive = async (
     progress: ProgressCallback,
     token: CancellationToken
-  ): Promise<DatabaseItem | undefined> => {
+  ): Promise<void> => {
     try {
-      return await this.chooseAndSetDatabase(false, progress, token);
+      await this.chooseAndSetDatabase(false, progress, token);
     } catch (e) {
-      showAndLogErrorMessage(e.message);
-      return undefined;
+      void showAndLogErrorMessage(getErrorMessage(e));
     }
   };
 
   handleChooseDatabaseInternet = async (
     progress: ProgressCallback,
     token: CancellationToken
-  ): Promise<
-    DatabaseItem | undefined
-  > => {
+  ): Promise<DatabaseItem | undefined> => {
     return await promptImportInternetDatabase(
       this.databaseManager,
       this.storagePath,
       progress,
-      token
+      token,
+      this.queryServer?.cliServer
+    );
+  };
+
+  handleChooseDatabaseGithub = async (
+    credentials: Credentials | undefined,
+    progress: ProgressCallback,
+    token: CancellationToken
+  ): Promise<DatabaseItem | undefined> => {
+    return await promptImportGithubDatabase(
+      this.databaseManager,
+      this.storagePath,
+      credentials,
+      progress,
+      token,
+      this.queryServer?.cliServer
     );
   };
 
@@ -452,7 +499,8 @@ export class DatabaseUI extends DisposableObject {
       this.databaseManager,
       this.storagePath,
       progress,
-      token
+      token,
+      this.queryServer?.cliServer
     );
   };
 
@@ -523,25 +571,9 @@ export class DatabaseUI extends DisposableObject {
     }
 
     // Search for upgrade scripts in any workspace folders available
-    const searchPath: string[] = getOnDiskWorkspaceFolders();
 
-    const upgradeInfo = await this.cliserver.resolveUpgrades(
-      databaseItem.contents.dbSchemeUri.fsPath,
-      searchPath
-    );
-
-    const { scripts, finalDbscheme } = upgradeInfo;
-
-    if (finalDbscheme === undefined) {
-      throw new Error('Could not determine target dbscheme to upgrade to.');
-    }
-    const targetDbSchemeUri = Uri.file(finalDbscheme);
-
-    await upgradeDatabase(
-      this.queryServer,
+    await this.queryServer.upgradeDatabaseExplicit(
       databaseItem,
-      targetDbSchemeUri,
-      getUpgradesDirectories(scripts),
       progress,
       token
     );
@@ -555,8 +587,7 @@ export class DatabaseUI extends DisposableObject {
       this.queryServer !== undefined &&
       this.databaseManager.currentDatabaseItem !== undefined
     ) {
-      await clearCacheInDatabase(
-        this.queryServer,
+      await this.queryServer.clearCacheInDatabase(
         this.databaseManager.currentDatabaseItem,
         progress,
         token
@@ -577,31 +608,32 @@ export class DatabaseUI extends DisposableObject {
           this.databaseManager,
           this.storagePath,
           progress,
-          token
+          token,
+          this.queryServer?.cliServer
         );
       } else {
-        await this.setCurrentDatabase(uri);
+        await this.setCurrentDatabase(progress, token, uri);
       }
     } catch (e) {
       // rethrow and let this be handled by default error handling.
       throw new Error(
-        `Could not set database to ${path.basename(uri.fsPath)}. Reason: ${
-        e.message
-        }`
+        `Could not set database to ${path.basename(uri.fsPath)}. Reason: ${getErrorMessage(e)}`
       );
     }
   };
 
   private handleRemoveDatabase = async (
+    progress: ProgressCallback,
+    token: CancellationToken,
     databaseItem: DatabaseItem,
     multiSelect: DatabaseItem[] | undefined
   ): Promise<void> => {
     if (multiSelect?.length) {
-      multiSelect.forEach((dbItem) =>
-        this.databaseManager.removeDatabaseItem(dbItem)
-      );
+      await Promise.all(multiSelect.map((dbItem) =>
+        this.databaseManager.removeDatabaseItem(progress, token, dbItem)
+      ));
     } else {
-      this.databaseManager.removeDatabaseItem(databaseItem);
+      await this.databaseManager.removeDatabaseItem(progress, token, databaseItem);
     }
   };
 
@@ -617,7 +649,7 @@ export class DatabaseUI extends DisposableObject {
     });
 
     if (newName) {
-      this.databaseManager.renameDatabaseItem(databaseItem, newName);
+      await this.databaseManager.renameDatabaseItem(databaseItem, newName);
     }
   };
 
@@ -634,6 +666,24 @@ export class DatabaseUI extends DisposableObject {
     }
   };
 
+  /**
+   * Adds the source folder of a CodeQL database to the workspace.
+   * When a database is first added in the "Databases" view, its source folder is added to the workspace.
+   * If the source folder is removed from the workspace for some reason, we want to be able to re-add it if need be.
+   */
+  private handleAddSource = async (
+    databaseItem: DatabaseItem,
+    multiSelect: DatabaseItem[] | undefined
+  ): Promise<void> => {
+    if (multiSelect?.length) {
+      for (const dbItem of multiSelect) {
+        await this.databaseManager.addDatabaseSourceArchiveFolder(dbItem);
+      }
+    } else {
+      await this.databaseManager.addDatabaseSourceArchiveFolder(databaseItem);
+    }
+  };
+
   /**
    * Return the current database directory. If we don't already have a
    * current database, ask the user for one, and return that, or
@@ -651,11 +701,13 @@ export class DatabaseUI extends DisposableObject {
   }
 
   private async setCurrentDatabase(
+    progress: ProgressCallback,
+    token: CancellationToken,
     uri: Uri
   ): Promise<DatabaseItem | undefined> {
     let databaseItem = this.databaseManager.findDatabaseItem(uri);
     if (databaseItem === undefined) {
-      databaseItem = await this.databaseManager.openDatabase(uri);
+      databaseItem = await this.databaseManager.openDatabase(progress, token, uri);
     }
     await this.databaseManager.setCurrentDatabaseItem(databaseItem);
 
@@ -672,7 +724,6 @@ export class DatabaseUI extends DisposableObject {
     token: CancellationToken,
   ): Promise<DatabaseItem | undefined> {
     const uri = await chooseDatabaseDir(byFolder);
-
     if (!uri) {
       return undefined;
     }
@@ -680,7 +731,7 @@ export class DatabaseUI extends DisposableObject {
     if (byFolder) {
       const fixedUri = await this.fixDbUri(uri);
       // we are selecting a database folder
-      return await this.setCurrentDatabase(fixedUri);
+      return await this.setCurrentDatabase(progress, token, fixedUri);
     } else {
       // we are selecting a database archive. Must unzip into a workspace-controlled area
       // before importing.
@@ -689,7 +740,8 @@ export class DatabaseUI extends DisposableObject {
         this.databaseManager,
         this.storagePath,
         progress,
-        token
+        token,
+        this.queryServer?.cliServer
       );
     }
   }
@@ -698,10 +750,10 @@ export class DatabaseUI extends DisposableObject {
    * Perform some heuristics to ensure a proper database location is chosen.
    *
    * 1. If the selected URI to add is a file, choose the containing directory
-   * 2. If the selected URI is a directory matching db-*, choose the containing directory
+   * 2. If the selected URI appears to be a db language folder, choose the containing directory
    * 3. choose the current directory
    *
-   * @param uri a URI that is a datbase folder or inside it
+   * @param uri a URI that is a database folder or inside it
    *
    * @return the actual database folder found by using the heuristics above.
    */
@@ -711,7 +763,7 @@ export class DatabaseUI extends DisposableObject {
       dbPath = path.dirname(dbPath);
     }
 
-    if (isLikelyDbLanguageFolder(dbPath)) {
+    if (await isLikelyDbLanguageFolder(dbPath)) {
       dbPath = path.dirname(dbPath);
     }
     return Uri.file(dbPath);

extensions/ql-vscode/src/databases.ts

@@ -4,11 +4,21 @@ import * as path from 'path';
 import * as vscode from 'vscode';
 import * as cli from './cli';
 import { ExtensionContext } from 'vscode';
-import { showAndLogErrorMessage, showAndLogWarningMessage, showAndLogInformationMessage } from './helpers';
+import {
+  showAndLogErrorMessage,
+  showAndLogWarningMessage,
+  showAndLogInformationMessage,
+  isLikelyDatabaseRoot
+} from './helpers';
+import {
+  ProgressCallback,
+  withProgress
+} from './commandRunner';
 import { zipArchiveScheme, encodeArchiveBasePath, decodeSourceArchiveUri, encodeSourceArchiveUri } from './archive-filesystem-provider';
-import { DisposableObject } from './vscode-utils/disposable-object';
-import { QueryServerConfig } from './config';
+import { DisposableObject } from './pure/disposable-object';
 import { Logger, logger } from './logging';
+import { getErrorMessage } from './pure/helpers-pure';
+import { QueryRunner } from './queryRunner';
 
 /**
  * databases.ts
@@ -36,11 +46,13 @@ export interface DatabaseOptions {
   displayName?: string;
   ignoreSourceArchive?: boolean;
   dateAdded?: number | undefined;
+  language?: string;
 }
 
-interface FullDatabaseOptions extends DatabaseOptions {
+export interface FullDatabaseOptions extends DatabaseOptions {
   ignoreSourceArchive: boolean;
   dateAdded: number | undefined;
+  language: string | undefined;
 }
 
 interface PersistedDatabaseItem {
@@ -103,30 +115,31 @@ async function findDataset(parentDirectory: string): Promise<vscode.Uri> {
 
   const dbAbsolutePath = path.join(parentDirectory, dbRelativePaths[0]);
   if (dbRelativePaths.length > 1) {
-    showAndLogWarningMessage(`Found multiple dataset directories in database, using '${dbAbsolutePath}'.`);
+    void showAndLogWarningMessage(`Found multiple dataset directories in database, using '${dbAbsolutePath}'.`);
   }
 
   return vscode.Uri.file(dbAbsolutePath);
 }
 
-async function findSourceArchive(
+// exported for testing
+export async function findSourceArchive(
   databasePath: string, silent = false
 ): Promise<vscode.Uri | undefined> {
-
   const relativePaths = ['src', 'output/src_archive'];
 
   for (const relativePath of relativePaths) {
     const basePath = path.join(databasePath, relativePath);
     const zipPath = basePath + '.zip';
 
-    if (await fs.pathExists(basePath)) {
-      return vscode.Uri.file(basePath);
-    } else if (await fs.pathExists(zipPath)) {
+    // Prefer using a zip archive over a directory.
+    if (await fs.pathExists(zipPath)) {
       return encodeArchiveBasePath(zipPath);
+    } else if (await fs.pathExists(basePath)) {
+      return vscode.Uri.file(basePath);
     }
   }
   if (!silent) {
-    showAndLogInformationMessage(
+    void showAndLogInformationMessage(
       `Could not find source archive for database '${databasePath}'. Assuming paths are absolute.`
     );
   }
@@ -134,7 +147,7 @@ async function findSourceArchive(
 }
 
 async function resolveDatabase(
-  databasePath: string
+  databasePath: string,
 ): Promise<DatabaseContents> {
 
   const name = path.basename(databasePath);
@@ -149,7 +162,6 @@ async function resolveDatabase(
     datasetUri,
     sourceArchiveUri
   };
-
 }
 
 /** Gets the relative paths of all `.dbscheme` files in the given directory. */
@@ -157,7 +169,9 @@ async function getDbSchemeFiles(dbDirectory: string): Promise<string[]> {
   return await glob('*.dbscheme', { cwd: dbDirectory });
 }
 
-async function resolveDatabaseContents(uri: vscode.Uri): Promise<DatabaseContents> {
+async function resolveDatabaseContents(
+  uri: vscode.Uri,
+): Promise<DatabaseContents> {
   if (uri.scheme !== 'file') {
     throw new Error(`Database URI scheme '${uri.scheme}' not supported; only 'file' URIs are supported.`);
   }
@@ -193,6 +207,9 @@ export interface DatabaseItem {
   readonly databaseUri: vscode.Uri;
   /** The name of the database to be displayed in the UI */
   name: string;
+
+  /** The primary language of the database or empty string if unknown */
+  readonly language: string;
   /** The URI of the database's source archive, or `undefined` if no source archive is to be used. */
   readonly sourceArchive: vscode.Uri | undefined;
   /**
@@ -243,12 +260,27 @@ export interface DatabaseItem {
    * Returns the root uri of the virtual filesystem for this database's source archive,
    * as displayed in the filesystem explorer.
    */
-  getSourceArchiveExplorerUri(): vscode.Uri | undefined;
+  getSourceArchiveExplorerUri(): vscode.Uri;
 
   /**
    * Holds if `uri` belongs to this database's source archive.
    */
   belongsToSourceArchiveExplorerUri(uri: vscode.Uri): boolean;
+
+  /**
+   * Whether the database may be affected by test execution for the given path.
+   */
+  isAffectedByTest(testPath: string): Promise<boolean>;
+
+  /**
+   * Gets the state of this database, to be persisted in the workspace state.
+   */
+  getPersistedState(): PersistedDatabaseItem;
+
+  /**
+   * Verifies that this database item has a zipped source folder. Returns an error message if it does not.
+   */
+  verifyZippedSources(): string | undefined;
 }
 
 export enum DatabaseEventKind {
@@ -326,14 +358,12 @@ export class DatabaseItemImpl implements DatabaseItem {
       try {
         this._contents = await resolveDatabaseContents(this.databaseUri);
         this._error = undefined;
-      }
-      catch (e) {
+      } catch (e) {
         this._contents = undefined;
-        this._error = e;
+        this._error = e instanceof Error ? e : new Error(String(e));
         throw e;
       }
-    }
-    finally {
+    } finally {
       this.onChanged({
         kind: DatabaseEventKind.Refresh,
         item: this
@@ -427,16 +457,33 @@ export class DatabaseItemImpl implements DatabaseItem {
     return dbInfo.datasetFolder;
   }
 
+  public get language() {
+    return this.options.language || '';
+  }
+
   /**
    * Returns the root uri of the virtual filesystem for this database's source archive.
    */
-  public getSourceArchiveExplorerUri(): vscode.Uri | undefined {
+  public getSourceArchiveExplorerUri(): vscode.Uri {
     const sourceArchive = this.sourceArchive;
-    if (sourceArchive === undefined || !sourceArchive.fsPath.endsWith('.zip'))
-      return undefined;
+    if (sourceArchive === undefined || !sourceArchive.fsPath.endsWith('.zip')) {
+      throw new Error(this.verifyZippedSources());
+    }
     return encodeArchiveBasePath(sourceArchive.fsPath);
   }
 
+  public verifyZippedSources(): string | undefined {
+    const sourceArchive = this.sourceArchive;
+    if (sourceArchive === undefined) {
+      return `${this.name} has no source archive.`;
+    }
+
+    if (!sourceArchive.fsPath.endsWith('.zip')) {
+      return `${this.name} has a source folder that is unzipped.`;
+    }
+    return;
+  }
+
   /**
    * Holds if `uri` belongs to this database's source archive.
    */
@@ -446,6 +493,27 @@ export class DatabaseItemImpl implements DatabaseItem {
     return uri.scheme === zipArchiveScheme &&
       decodeSourceArchiveUri(uri).sourceArchiveZipPath === this.sourceArchive.fsPath;
   }
+
+  public async isAffectedByTest(testPath: string): Promise<boolean> {
+    const databasePath = this.databaseUri.fsPath;
+    if (!databasePath.endsWith('.testproj')) {
+      return false;
+    }
+    try {
+      const stats = await fs.stat(testPath);
+      if (stats.isDirectory()) {
+        return !path.relative(testPath, databasePath).startsWith('..');
+      } else {
+        // database for /one/two/three/test.ql is at /one/two/three/three.testproj
+        const testdir = path.dirname(testPath);
+        const testdirbase = path.basename(testdir);
+        return databasePath == path.join(testdir, testdirbase + '.testproj');
+      }
+    } catch {
+      // No information available for test path - assume database is unaffected.
+      return false;
+    }
+  }
 }
 
 /**
@@ -456,7 +524,7 @@ export class DatabaseItemImpl implements DatabaseItem {
 function eventFired<T>(event: vscode.Event<T>, timeoutMs = 1000): Promise<T | undefined> {
   return new Promise((res, _rej) => {
     const timeout = setTimeout(() => {
-      logger.log(`Waiting for event ${event} timed out after ${timeoutMs}ms`);
+      void logger.log(`Waiting for event ${event} timed out after ${timeoutMs}ms`);
       res(undefined);
       dispose();
     }, timeoutMs);
@@ -479,43 +547,63 @@ export class DatabaseManager extends DisposableObject {
   private readonly _onDidChangeCurrentDatabaseItem = this.push(new vscode.EventEmitter<DatabaseChangedEvent>());
   readonly onDidChangeCurrentDatabaseItem = this._onDidChangeCurrentDatabaseItem.event;
 
-  private readonly _databaseItems: DatabaseItemImpl[] = [];
+  private readonly _databaseItems: DatabaseItem[] = [];
   private _currentDatabaseItem: DatabaseItem | undefined = undefined;
 
   constructor(
-    private ctx: ExtensionContext,
-    public config: QueryServerConfig,
+    private readonly ctx: ExtensionContext,
+    private readonly qs: QueryRunner,
+    private readonly cli: cli.CodeQLCliServer,
     public logger: Logger
   ) {
     super();
 
-    this.loadPersistedState();  // Let this run async.
+    qs.onStart(this.reregisterDatabases.bind(this));
   }
 
   public async openDatabase(
-    uri: vscode.Uri, options?: DatabaseOptions
+    progress: ProgressCallback,
+    token: vscode.CancellationToken,
+    uri: vscode.Uri,
+    displayName?: string
   ): Promise<DatabaseItem> {
-
     const contents = await resolveDatabaseContents(uri);
-    const realOptions = options || {};
     // Ignore the source archive for QLTest databases by default.
     const isQLTestDatabase = path.extname(uri.fsPath) === '.testproj';
     const fullOptions: FullDatabaseOptions = {
-      ignoreSourceArchive: (realOptions.ignoreSourceArchive !== undefined) ?
-        realOptions.ignoreSourceArchive : isQLTestDatabase,
-      displayName: realOptions.displayName,
-      dateAdded: realOptions.dateAdded || Date.now()
+      ignoreSourceArchive: isQLTestDatabase,
+      // If a displayName is not passed in, the basename of folder containing the database is used.
+      displayName,
+      dateAdded: Date.now(),
+      language: await this.getPrimaryLanguage(uri.fsPath)
     };
     const databaseItem = new DatabaseItemImpl(uri, contents, fullOptions, (event) => {
       this._onDidChangeDatabaseItem.fire(event);
     });
-    await this.addDatabaseItem(databaseItem);
+
+    await this.addDatabaseItem(progress, token, databaseItem);
     await this.addDatabaseSourceArchiveFolder(databaseItem);
 
     return databaseItem;
   }
 
-  private async addDatabaseSourceArchiveFolder(item: DatabaseItem) {
+  private async reregisterDatabases(
+    progress: ProgressCallback,
+    token: vscode.CancellationToken
+  ) {
+    let completed = 0;
+    await Promise.all(this._databaseItems.map(async (databaseItem) => {
+      await this.registerDatabase(progress, token, databaseItem);
+      completed++;
+      progress({
+        maxStep: this._databaseItems.length,
+        step: completed,
+        message: 'Re-registering databases'
+      });
+    }));
+  }
+
+  public async addDatabaseSourceArchiveFolder(item: DatabaseItem) {
     // The folder may already be in workspace state from a previous
     // session. If not, add it.
     const index = this.getDatabaseWorkspaceFolderIndex(item);
@@ -531,36 +619,41 @@ export class DatabaseManager extends DisposableObject {
       // This is undesirable, as we might be adding and removing many
       // workspace folders as the user adds and removes databases.
       const end = (vscode.workspace.workspaceFolders || []).length;
+
+      const msg = item.verifyZippedSources();
+      if (msg) {
+        void logger.log(`Could not add source folder because ${msg}`);
+        return;
+      }
+
       const uri = item.getSourceArchiveExplorerUri();
-      if (uri === undefined) {
-        logger.log(`Couldn't obtain file explorer uri for ${item.name}`);
-      }
-      else {
-        logger.log(`Adding workspace folder for ${item.name} source archive at index ${end}`);
-        if ((vscode.workspace.workspaceFolders || []).length < 2) {
-          // Adding this workspace folder makes the workspace
-          // multi-root, which may surprise the user. Let them know
-          // we're doing this.
-          vscode.window.showInformationMessage(`Adding workspace folder for source archive of database ${item.name}.`);
-        }
-        vscode.workspace.updateWorkspaceFolders(end, 0, {
-          name: `[${item.name} source archive]`,
-          uri,
-        });
-        // vscode api documentation says we must to wait for this event
-        // between multiple `updateWorkspaceFolders` calls.
-        await eventFired(vscode.workspace.onDidChangeWorkspaceFolders);
+      void logger.log(`Adding workspace folder for ${item.name} source archive at index ${end}`);
+      if ((vscode.workspace.workspaceFolders || []).length < 2) {
+        // Adding this workspace folder makes the workspace
+        // multi-root, which may surprise the user. Let them know
+        // we're doing this.
+        void vscode.window.showInformationMessage(`Adding workspace folder for source archive of database ${item.name}.`);
       }
+      vscode.workspace.updateWorkspaceFolders(end, 0, {
+        name: `[${item.name} source archive]`,
+        uri,
+      });
+      // vscode api documentation says we must to wait for this event
+      // between multiple `updateWorkspaceFolders` calls.
+      await eventFired(vscode.workspace.onDidChangeWorkspaceFolders);
     }
   }
 
   private async createDatabaseItemFromPersistedState(
+    progress: ProgressCallback,
+    token: vscode.CancellationToken,
     state: PersistedDatabaseItem
   ): Promise<DatabaseItem> {
 
     let displayName: string | undefined = undefined;
     let ignoreSourceArchive = false;
     let dateAdded = undefined;
+    let language = undefined;
     if (state.options) {
       if (typeof state.options.displayName === 'string') {
         displayName = state.options.displayName;
@@ -571,43 +664,73 @@ export class DatabaseManager extends DisposableObject {
       if (typeof state.options.dateAdded === 'number') {
         dateAdded = state.options.dateAdded;
       }
+      language = state.options.language;
     }
+
+    const dbBaseUri = vscode.Uri.parse(state.uri, true);
+    if (language === undefined) {
+      // we haven't been successful yet at getting the language. try again
+      language = await this.getPrimaryLanguage(dbBaseUri.fsPath);
+    }
+
     const fullOptions: FullDatabaseOptions = {
       ignoreSourceArchive,
       displayName,
-      dateAdded
+      dateAdded,
+      language
     };
-    const item = new DatabaseItemImpl(vscode.Uri.parse(state.uri, true), undefined, fullOptions,
+    const item = new DatabaseItemImpl(dbBaseUri, undefined, fullOptions,
       (event) => {
         this._onDidChangeDatabaseItem.fire(event);
       });
-    await this.addDatabaseItem(item);
 
+    await this.addDatabaseItem(progress, token, item);
     return item;
   }
 
-  private async loadPersistedState(): Promise<void> {
-    const currentDatabaseUri = this.ctx.workspaceState.get<string>(CURRENT_DB);
-    const databases = this.ctx.workspaceState.get<PersistedDatabaseItem[]>(DB_LIST, []);
-
-    try {
-      for (const database of databases) {
-        const databaseItem = await this.createDatabaseItemFromPersistedState(database);
+  public async loadPersistedState(): Promise<void> {
+    return withProgress({
+      location: vscode.ProgressLocation.Notification
+    },
+      async (progress, token) => {
+        const currentDatabaseUri = this.ctx.workspaceState.get<string>(CURRENT_DB);
+        const databases = this.ctx.workspaceState.get<PersistedDatabaseItem[]>(DB_LIST, []);
+        let step = 0;
+        progress({
+          maxStep: databases.length,
+          message: 'Loading persisted databases',
+          step
+        });
         try {
-          await databaseItem.refresh();
-          if (currentDatabaseUri === database.uri) {
-            this.setCurrentDatabaseItem(databaseItem, true);
+          void this.logger.log(`Found ${databases.length} persisted databases: ${databases.map(db => db.uri).join(', ')}`);
+          for (const database of databases) {
+            progress({
+              maxStep: databases.length,
+              message: `Loading ${database.options?.displayName || 'databases'}`,
+              step: ++step
+            });
+
+            const databaseItem = await this.createDatabaseItemFromPersistedState(progress, token, database);
+            try {
+              await databaseItem.refresh();
+              await this.registerDatabase(progress, token, databaseItem);
+              if (currentDatabaseUri === database.uri) {
+                await this.setCurrentDatabaseItem(databaseItem, true);
+              }
+              void this.logger.log(`Loaded database ${databaseItem.name} at URI ${database.uri}.`);
+            } catch (e) {
+              // When loading from persisted state, leave invalid databases in the list. They will be
+              // marked as invalid, and cannot be set as the current database.
+              void this.logger.log(`Error loading database ${database.uri}: ${e}.`);
+            }
           }
+        } catch (e) {
+          // database list had an unexpected type - nothing to be done?
+          void showAndLogErrorMessage(`Database list loading failed: ${getErrorMessage(e)}`);
         }
-        catch (e) {
-          // When loading from persisted state, leave invalid databases in the list. They will be
-          // marked as invalid, and cannot be set as the current database.
-        }
-      }
-    } catch (e) {
-      // database list had an unexpected type - nothing to be done?
-      showAndLogErrorMessage(`Database list loading failed: ${e.message}`);
-    }
+
+        void this.logger.log('Finished loading persisted databases.');
+      });
   }
 
   public get databaseItems(): readonly DatabaseItem[] {
@@ -618,8 +741,10 @@ export class DatabaseManager extends DisposableObject {
     return this._currentDatabaseItem;
   }
 
-  public async setCurrentDatabaseItem(item: DatabaseItem | undefined,
-    skipRefresh = false): Promise<void> {
+  public async setCurrentDatabaseItem(
+    item: DatabaseItem | undefined,
+    skipRefresh = false
+  ): Promise<void> {
 
     if (!skipRefresh && (item !== undefined)) {
       await item.refresh();  // Will throw on invalid database.
@@ -627,6 +752,9 @@ export class DatabaseManager extends DisposableObject {
     if (this._currentDatabaseItem !== item) {
       this._currentDatabaseItem = item;
       this.updatePersistedCurrentDatabaseItem();
+
+      await vscode.commands.executeCommand('setContext', 'codeQL.currentDatabaseItem', item?.name);
+
       this._onDidChangeCurrentDatabaseItem.fire({
         item,
         kind: DatabaseEventKind.Change
@@ -653,9 +781,20 @@ export class DatabaseManager extends DisposableObject {
     return this._databaseItems.find(item => item.sourceArchive && item.sourceArchive.toString(true) === uriString);
   }
 
-  private async addDatabaseItem(item: DatabaseItemImpl) {
+  private async addDatabaseItem(
+    progress: ProgressCallback,
+    token: vscode.CancellationToken,
+    item: DatabaseItem
+  ) {
     this._databaseItems.push(item);
-    this.updatePersistedDatabaseList();
+    await this.updatePersistedDatabaseList();
+
+    // Add this database item to the allow-list
+    // Database items reconstituted from persisted state
+    // will not have their contents yet.
+    if (item.contents?.datasetUri) {
+      await this.registerDatabase(progress, token, item);
+    }
     // note that we use undefined as the item in order to reset the entire tree
     this._onDidChangeDatabaseItem.fire({
       item: undefined,
@@ -665,7 +804,7 @@ export class DatabaseManager extends DisposableObject {
 
   public async renameDatabaseItem(item: DatabaseItem, newName: string) {
     item.name = newName;
-    this.updatePersistedDatabaseList();
+    await this.updatePersistedDatabaseList();
     this._onDidChangeDatabaseItem.fire({
       // pass undefined so that the entire tree is rebuilt in order to re-sort
       item: undefined,
@@ -673,28 +812,38 @@ export class DatabaseManager extends DisposableObject {
     });
   }
 
-  public removeDatabaseItem(item: DatabaseItem) {
-    if (this._currentDatabaseItem == item)
+  public async removeDatabaseItem(
+    progress: ProgressCallback,
+    token: vscode.CancellationToken,
+    item: DatabaseItem
+  ) {
+    if (this._currentDatabaseItem == item) {
       this._currentDatabaseItem = undefined;
+    }
     const index = this.databaseItems.findIndex(searchItem => searchItem === item);
     if (index >= 0) {
       this._databaseItems.splice(index, 1);
     }
-    this.updatePersistedDatabaseList();
+    await this.updatePersistedDatabaseList();
 
     // Delete folder from workspace, if it is still there
-    const folderIndex = (vscode.workspace.workspaceFolders || []).findIndex(folder => item.belongsToSourceArchiveExplorerUri(folder.uri));
-    if (index >= 0) {
-      logger.log(`Removing workspace folder at index ${folderIndex}`);
+    const folderIndex = (vscode.workspace.workspaceFolders || []).findIndex(
+      folder => item.belongsToSourceArchiveExplorerUri(folder.uri)
+    );
+    if (folderIndex >= 0) {
+      void logger.log(`Removing workspace folder at index ${folderIndex}`);
       vscode.workspace.updateWorkspaceFolders(folderIndex, 1);
     }
 
+    // Remove this database item from the allow-list
+    await this.deregisterDatabase(progress, token, item);
+
     // Delete folder from file system only if it is controlled by the extension
     if (this.isExtensionControlledLocation(item.databaseUri)) {
-      logger.log('Deleting database from filesystem.');
-      fs.remove(item.databaseUri.path).then(
-        () => logger.log(`Deleted '${item.databaseUri.path}'`),
-        e => logger.log(`Failed to delete '${item.databaseUri.path}'. Reason: ${e.message}`));
+      void logger.log('Deleting database from filesystem.');
+      fs.remove(item.databaseUri.fsPath).then(
+        () => void logger.log(`Deleted '${item.databaseUri.fsPath}'`),
+        e => void logger.log(`Failed to delete '${item.databaseUri.fsPath}'. Reason: ${getErrorMessage(e)}`));
     }
 
     // note that we use undefined as the item in order to reset the entire tree
@@ -704,18 +853,50 @@ export class DatabaseManager extends DisposableObject {
     });
   }
 
+  private async deregisterDatabase(
+    progress: ProgressCallback,
+    token: vscode.CancellationToken,
+    dbItem: DatabaseItem,
+  ) {
+    await this.qs.deregisterDatabase(progress, token, dbItem);
+  }
+  private async registerDatabase(
+    progress: ProgressCallback,
+    token: vscode.CancellationToken,
+    dbItem: DatabaseItem,
+  ) {
+    await this.qs.registerDatabase(progress, token, dbItem);
+  }
+
   private updatePersistedCurrentDatabaseItem(): void {
-    this.ctx.workspaceState.update(CURRENT_DB, this._currentDatabaseItem ?
+    void this.ctx.workspaceState.update(CURRENT_DB, this._currentDatabaseItem ?
       this._currentDatabaseItem.databaseUri.toString(true) : undefined);
   }
 
-  private updatePersistedDatabaseList(): void {
-    this.ctx.workspaceState.update(DB_LIST, this._databaseItems.map(item => item.getPersistedState()));
+  private async updatePersistedDatabaseList(): Promise<void> {
+    await this.ctx.workspaceState.update(DB_LIST, this._databaseItems.map(item => item.getPersistedState()));
   }
 
   private isExtensionControlledLocation(uri: vscode.Uri) {
     const storagePath = this.ctx.storagePath || this.ctx.globalStoragePath;
-    return uri.path.startsWith(storagePath);
+    // the uri.fsPath function on windows returns a lowercase drive letter,
+    // but storagePath will have an uppercase drive letter. Be sure to compare
+    // URIs to URIs only
+    if (storagePath) {
+      return uri.fsPath.startsWith(vscode.Uri.file(storagePath).fsPath);
+    }
+    return false;
+  }
+
+  private async getPrimaryLanguage(dbPath: string) {
+    if (!(await this.cli.cliConstraints.supportsLanguageName())) {
+      // return undefined so that we recalculate on restart until the cli is at a version that
+      // supports this feature. This recalculation is cheap since we avoid calling into the cli
+      // unless we know it can return the langauges property.
+      return undefined;
+    }
+    const dbInfo = await this.cli.resolveDatabase(dbPath);
+    return dbInfo.languages?.[0] || '';
   }
 }
 
@@ -728,23 +909,3 @@ export function getUpgradesDirectories(scripts: string[]): vscode.Uri[] {
   const uniqueParentDirs = new Set(parentDirs);
   return Array.from(uniqueParentDirs).map(filePath => vscode.Uri.file(filePath));
 }
-
-
-// TODO: Get the list of supported languages from a list that will be auto-updated.
-
-export async function isLikelyDatabaseRoot(fsPath: string) {
-  const [a, b, c] = (await Promise.all([
-    // databases can have either .dbinfo or codeql-database.yml.
-    fs.pathExists(path.join(fsPath, '.dbinfo')),
-    fs.pathExists(path.join(fsPath, 'codeql-database.yml')),
-
-    // they *must* have a db-language folder
-    (await fs.readdir(fsPath)).some(isLikelyDbLanguageFolder)
-  ]));
-
-  return (a || b) && c;
-}
-
-export function isLikelyDbLanguageFolder(dbPath: string) {
-  return !!path.basename(dbPath).startsWith('db-');
-}

extensions/ql-vscode/src/discovery.ts

@@ -1,5 +1,5 @@
-import { DisposableObject } from './vscode-utils/disposable-object';
-import { showAndLogErrorMessage } from './helpers';
+import { DisposableObject } from './pure/disposable-object';
+import { logger } from './logging';
 
 /**
  * Base class for "discovery" operations, which scan the file system to find specific kinds of
@@ -59,23 +59,23 @@ export abstract class Discovery<T> extends DisposableObject {
         this.discoveryInProgress = false;
         this.update(results);
       }
-    });
+    })
 
-    discoveryPromise.catch(err => {
-      showAndLogErrorMessage(`${this.name} failed. Reason: ${err.message}`);
-    });
+      .catch(err => {
+        void logger.log(`${this.name} failed. Reason: ${err.message}`);
+      })
 
-    discoveryPromise.finally(() => {
-      if (this.retry) {
-        // Another refresh request came in while we were still running a previous discovery
-        // operation. Since the discovery results we just computed are now stale, we'll launch
-        // another discovery operation instead of updating.
-        // Note that by doing this inside of `finally`, we will relaunch discovery even if the
-        // initial discovery operation failed.
-        this.retry = false;
-        this.launchDiscovery();
-      }
-    });
+      .finally(() => {
+        if (this.retry) {
+          // Another refresh request came in while we were still running a previous discovery
+          // operation. Since the discovery results we just computed are now stale, we'll launch
+          // another discovery operation instead of updating.
+          // Note that by doing this inside of `finally`, we will relaunch discovery even if the
+          // initial discovery operation failed.
+          this.retry = false;
+          this.launchDiscovery();
+        }
+      });
   }
 
   /**

extensions/ql-vscode/src/distribution.ts

@@ -7,10 +7,15 @@ import * as unzipper from 'unzipper';
 import * as url from 'url';
 import { ExtensionContext, Event } from 'vscode';
 import { DistributionConfig } from './config';
-import { InvocationRateLimiter, InvocationRateLimiterResultKind, showAndLogErrorMessage } from './helpers';
+import {
+  InvocationRateLimiter,
+  InvocationRateLimiterResultKind,
+  showAndLogErrorMessage,
+  showAndLogWarningMessage
+} from './helpers';
 import { logger } from './logging';
-import * as helpers from './helpers';
 import { getCodeQlCliVersion } from './cli-version';
+import { ProgressCallback, reportStreamProgress } from './commandRunner';
 
 /**
  * distribution.ts
@@ -49,16 +54,36 @@ export interface DistributionProvider {
 }
 
 export class DistributionManager implements DistributionProvider {
-  constructor(extensionContext: ExtensionContext, config: DistributionConfig, versionRange: semver.Range) {
-    this._config = config;
-    this._extensionSpecificDistributionManager = new ExtensionSpecificDistributionManager(extensionContext, config, versionRange);
+
+  /**
+   * Get the name of the codeql cli installation we prefer to install, based on our current platform.
+   */
+  public static getRequiredAssetName(): string {
+    switch (os.platform()) {
+      case 'linux':
+        return 'codeql-linux64.zip';
+      case 'darwin':
+        return 'codeql-osx64.zip';
+      case 'win32':
+        return 'codeql-win64.zip';
+      default:
+        return 'codeql.zip';
+    }
+  }
+
+  constructor(
+    public readonly config: DistributionConfig,
+    private readonly versionRange: semver.Range,
+    extensionContext: ExtensionContext
+  ) {
     this._onDidChangeDistribution = config.onDidChangeConfiguration;
-    this._updateCheckRateLimiter = new InvocationRateLimiter(
+    this.extensionSpecificDistributionManager =
+      new ExtensionSpecificDistributionManager(config, versionRange, extensionContext);
+    this.updateCheckRateLimiter = new InvocationRateLimiter(
       extensionContext,
       'extensionSpecificDistributionUpdateCheck',
-      () => this._extensionSpecificDistributionManager.checkForUpdatesToDistribution()
+      () => this.extensionSpecificDistributionManager.checkForUpdatesToDistribution()
     );
-    this._versionRange = versionRange;
   }
 
   /**
@@ -95,9 +120,9 @@ export class DistributionManager implements DistributionProvider {
      * - If the user is using an extension-managed CLI, then prereleases are only accepted when the
      * includePrerelease config option is set.
      */
-    const includePrerelease = distribution.kind !== DistributionKind.ExtensionManaged || this._config.includePrerelease;
+    const includePrerelease = distribution.kind !== DistributionKind.ExtensionManaged || this.config.includePrerelease;
 
-    if (!semver.satisfies(version, this._versionRange, { includePrerelease })) {
+    if (!semver.satisfies(version, this.versionRange, { includePrerelease })) {
       return {
         distribution,
         kind: FindDistributionResultKind.IncompatibleDistribution,
@@ -126,9 +151,9 @@ export class DistributionManager implements DistributionProvider {
    */
   async getDistributionWithoutVersionCheck(): Promise<Distribution | undefined> {
     // Check config setting, then extension specific distribution, then PATH.
-    if (this._config.customCodeQlPath) {
-      if (!await fs.pathExists(this._config.customCodeQlPath)) {
-        showAndLogErrorMessage(`The CodeQL executable path is specified as "${this._config.customCodeQlPath}" ` +
+    if (this.config.customCodeQlPath) {
+      if (!await fs.pathExists(this.config.customCodeQlPath)) {
+        void showAndLogErrorMessage(`The CodeQL executable path is specified as "${this.config.customCodeQlPath}" ` +
           'by a configuration setting, but a CodeQL executable could not be found at that path. Please check ' +
           'that a CodeQL executable exists at the specified path or remove the setting.');
         return undefined;
@@ -137,18 +162,18 @@ export class DistributionManager implements DistributionProvider {
       // emit a warning if using a deprecated launcher and a non-deprecated launcher exists
       if (
         deprecatedCodeQlLauncherName() &&
-        this._config.customCodeQlPath.endsWith(deprecatedCodeQlLauncherName()!) &&
+        this.config.customCodeQlPath.endsWith(deprecatedCodeQlLauncherName()!) &&
         await this.hasNewLauncherName()
       ) {
         warnDeprecatedLauncher();
       }
       return {
-        codeQlPath: this._config.customCodeQlPath,
+        codeQlPath: this.config.customCodeQlPath,
         kind: DistributionKind.CustomPathConfig
       };
     }
 
-    const extensionSpecificCodeQlPath = await this._extensionSpecificDistributionManager.getCodeQlPathWithoutVersionCheck();
+    const extensionSpecificCodeQlPath = await this.extensionSpecificDistributionManager.getCodeQlPathWithoutVersionCheck();
     if (extensionSpecificCodeQlPath !== undefined) {
       return {
         codeQlPath: extensionSpecificCodeQlPath,
@@ -166,7 +191,7 @@ export class DistributionManager implements DistributionProvider {
           };
         }
       }
-      logger.log('INFO: Could not find CodeQL on path.');
+      void logger.log('INFO: Could not find CodeQL on path.');
     }
 
     return undefined;
@@ -181,12 +206,12 @@ export class DistributionManager implements DistributionProvider {
   public async checkForUpdatesToExtensionManagedDistribution(
     minSecondsSinceLastUpdateCheck: number): Promise<DistributionUpdateCheckResult> {
     const distribution = await this.getDistributionWithoutVersionCheck();
-    const extensionManagedCodeQlPath = await this._extensionSpecificDistributionManager.getCodeQlPathWithoutVersionCheck();
+    const extensionManagedCodeQlPath = await this.extensionSpecificDistributionManager.getCodeQlPathWithoutVersionCheck();
     if (distribution?.codeQlPath !== extensionManagedCodeQlPath) {
       // A distribution is present but it isn't managed by the extension.
       return createInvalidLocationResult();
     }
-    const updateCheckResult = await this._updateCheckRateLimiter.invokeFunctionIfIntervalElapsed(minSecondsSinceLastUpdateCheck);
+    const updateCheckResult = await this.updateCheckRateLimiter.invokeFunctionIfIntervalElapsed(minSecondsSinceLastUpdateCheck);
     switch (updateCheckResult.kind) {
       case InvocationRateLimiterResultKind.Invoked:
         return updateCheckResult.result;
@@ -200,9 +225,11 @@ export class DistributionManager implements DistributionProvider {
    *
    * Returns a failed promise if an unexpected error occurs during installation.
    */
-  public installExtensionManagedDistributionRelease(release: Release,
-    progressCallback?: helpers.ProgressCallback): Promise<void> {
-    return this._extensionSpecificDistributionManager.installDistributionRelease(release, progressCallback);
+  public installExtensionManagedDistributionRelease(
+    release: Release,
+    progressCallback?: ProgressCallback
+  ): Promise<void> {
+    return this.extensionSpecificDistributionManager.installDistributionRelease(release, progressCallback);
   }
 
   public get onDidChangeDistribution(): Event<void> | undefined {
@@ -215,27 +242,27 @@ export class DistributionManager implements DistributionProvider {
    * installation. False otherwise.
    */
   private async hasNewLauncherName(): Promise<boolean> {
-    if (!this._config.customCodeQlPath) {
+    if (!this.config.customCodeQlPath) {
       // not managed externally
       return false;
     }
-    const dir = path.dirname(this._config.customCodeQlPath);
+    const dir = path.dirname(this.config.customCodeQlPath);
     const newLaunderPath = path.join(dir, codeQlLauncherName());
     return await fs.pathExists(newLaunderPath);
   }
 
-  private readonly _config: DistributionConfig;
-  private readonly _extensionSpecificDistributionManager: ExtensionSpecificDistributionManager;
-  private readonly _updateCheckRateLimiter: InvocationRateLimiter<DistributionUpdateCheckResult>;
+  private readonly extensionSpecificDistributionManager: ExtensionSpecificDistributionManager;
+  private readonly updateCheckRateLimiter: InvocationRateLimiter<DistributionUpdateCheckResult>;
   private readonly _onDidChangeDistribution: Event<void> | undefined;
-  private readonly _versionRange: semver.Range;
 }
 
 class ExtensionSpecificDistributionManager {
-  constructor(extensionContext: ExtensionContext, config: DistributionConfig, versionRange: semver.Range) {
-    this._extensionContext = extensionContext;
-    this._config = config;
-    this._versionRange = versionRange;
+  constructor(
+    private readonly config: DistributionConfig,
+    private readonly versionRange: semver.Range,
+    private readonly extensionContext: ExtensionContext
+  ) {
+    /**/
   }
 
   public async getCodeQlPathWithoutVersionCheck(): Promise<string | undefined> {
@@ -249,7 +276,7 @@ class ExtensionSpecificDistributionManager {
       try {
         await this.removeDistribution();
       } catch (e) {
-        logger.log('WARNING: Tried to remove corrupted CodeQL CLI at ' +
+        void logger.log('WARNING: Tried to remove corrupted CodeQL CLI at ' +
           `${this.getDistributionStoragePath()} but encountered an error: ${e}.`);
       }
     }
@@ -283,29 +310,29 @@ class ExtensionSpecificDistributionManager {
    * Returns a failed promise if an unexpected error occurs during installation.
    */
   public async installDistributionRelease(release: Release,
-    progressCallback?: helpers.ProgressCallback): Promise<void> {
+    progressCallback?: ProgressCallback): Promise<void> {
     await this.downloadDistribution(release, progressCallback);
     // Store the installed release within the global extension state.
-    this.storeInstalledRelease(release);
+    await this.storeInstalledRelease(release);
   }
 
   private async downloadDistribution(release: Release,
-    progressCallback?: helpers.ProgressCallback): Promise<void> {
+    progressCallback?: ProgressCallback): Promise<void> {
     try {
       await this.removeDistribution();
     } catch (e) {
-      logger.log(`Tried to clean up old version of CLI at ${this.getDistributionStoragePath()} ` +
+      void logger.log(`Tried to clean up old version of CLI at ${this.getDistributionStoragePath()} ` +
         `but encountered an error: ${e}.`);
     }
 
     // Filter assets to the unique one that we require.
-    const requiredAssetName = this.getRequiredAssetName();
+    const requiredAssetName = DistributionManager.getRequiredAssetName();
     const assets = release.assets.filter(asset => asset.name === requiredAssetName);
     if (assets.length === 0) {
       throw new Error(`Invariant violation: chose a release to install that didn't have ${requiredAssetName}`);
     }
     if (assets.length > 1) {
-      logger.log('WARNING: chose a release with more than one asset to install, found ' +
+      void logger.log('WARNING: chose a release with more than one asset to install, found ' +
         assets.map(asset => asset.name).join(', '));
     }
 
@@ -317,27 +344,8 @@ class ExtensionSpecificDistributionManager {
       const archiveFile = fs.createWriteStream(archivePath);
 
       const contentLength = assetStream.headers.get('content-length');
-      let numBytesDownloaded = 0;
-
-      if (progressCallback && contentLength !== null) {
-        const totalNumBytes = parseInt(contentLength, 10);
-        const bytesToDisplayMB = (numBytes: number): string => `${(numBytes / (1024 * 1024)).toFixed(1)} MB`;
-        const updateProgress = (): void => {
-          progressCallback({
-            step: numBytesDownloaded,
-            maxStep: totalNumBytes,
-            message: `Downloading CodeQL CLI… [${bytesToDisplayMB(numBytesDownloaded)} of ${bytesToDisplayMB(totalNumBytes)}]`,
-          });
-        };
-
-        // Display the progress straight away rather than waiting for the first chunk.
-        updateProgress();
-
-        assetStream.body.on('data', data => {
-          numBytesDownloaded += data.length;
-          updateProgress();
-        });
-      }
+      const totalNumBytes = contentLength ? parseInt(contentLength, 10) : undefined;
+      reportStreamProgress(assetStream.body, `Downloading CodeQL CLI ${release.name}…`, totalNumBytes, progressCallback);
 
       await new Promise((resolve, reject) =>
         assetStream.body.pipe(archiveFile)
@@ -347,7 +355,7 @@ class ExtensionSpecificDistributionManager {
 
       await this.bumpDistributionFolderIndex();
 
-      logger.log(`Extracting CodeQL CLI to ${this.getDistributionStoragePath()}`);
+      void logger.log(`Extracting CodeQL CLI to ${this.getDistributionStoragePath()}`);
       await extractZipArchive(archivePath, this.getDistributionStoragePath());
     } finally {
       await fs.remove(tmpDirectory);
@@ -360,37 +368,27 @@ class ExtensionSpecificDistributionManager {
    * This should not be called for a distribution that is currently in use, as remove may fail.
    */
   private async removeDistribution(): Promise<void> {
-    this.storeInstalledRelease(undefined);
+    await this.storeInstalledRelease(undefined);
     if (await fs.pathExists(this.getDistributionStoragePath())) {
       await fs.remove(this.getDistributionStoragePath());
     }
   }
 
-  /**
-   * Get the name of the codeql cli installation we prefer to install, based on our current platform.
-   */
-  private getRequiredAssetName(): string {
-    if (os.platform() === 'linux') return 'codeql-linux64.zip';
-    if (os.platform() === 'darwin') return 'codeql-osx64.zip';
-    if (os.platform() === 'win32') return 'codeql-win64.zip';
-    return 'codeql.zip';
-  }
-
   private async getLatestRelease(): Promise<Release> {
-    const requiredAssetName = this.getRequiredAssetName();
-    logger.log(`Searching for latest release including ${requiredAssetName}.`);
+    const requiredAssetName = DistributionManager.getRequiredAssetName();
+    void logger.log(`Searching for latest release including ${requiredAssetName}.`);
     return this.createReleasesApiConsumer().getLatestRelease(
-      this._versionRange,
-      this._config.includePrerelease,
+      this.versionRange,
+      this.config.includePrerelease,
       release => {
         const matchingAssets = release.assets.filter(asset => asset.name === requiredAssetName);
         if (matchingAssets.length === 0) {
           // For example, this could be a release with no platform-specific assets.
-          logger.log(`INFO: Ignoring a release with no assets named ${requiredAssetName}`);
+          void logger.log(`INFO: Ignoring a release with no assets named ${requiredAssetName}`);
           return false;
         }
         if (matchingAssets.length > 1) {
-          logger.log(`WARNING: Ignoring a release with more than one asset named ${requiredAssetName}`);
+          void logger.log(`WARNING: Ignoring a release with more than one asset named ${requiredAssetName}`);
           return false;
         }
         return true;
@@ -399,23 +397,23 @@ class ExtensionSpecificDistributionManager {
   }
 
   private createReleasesApiConsumer(): ReleasesApiConsumer {
-    const ownerName = this._config.ownerName ? this._config.ownerName : DEFAULT_DISTRIBUTION_OWNER_NAME;
-    const repositoryName = this._config.repositoryName ? this._config.repositoryName : DEFAULT_DISTRIBUTION_REPOSITORY_NAME;
-    return new ReleasesApiConsumer(ownerName, repositoryName, this._config.personalAccessToken);
+    const ownerName = this.config.ownerName ? this.config.ownerName : DEFAULT_DISTRIBUTION_OWNER_NAME;
+    const repositoryName = this.config.repositoryName ? this.config.repositoryName : DEFAULT_DISTRIBUTION_REPOSITORY_NAME;
+    return new ReleasesApiConsumer(ownerName, repositoryName, this.config.personalAccessToken);
   }
 
   private async bumpDistributionFolderIndex(): Promise<void> {
-    const index = this._extensionContext.globalState.get(
+    const index = this.extensionContext.globalState.get(
       ExtensionSpecificDistributionManager._currentDistributionFolderIndexStateKey, 0);
-    await this._extensionContext.globalState.update(
+    await this.extensionContext.globalState.update(
       ExtensionSpecificDistributionManager._currentDistributionFolderIndexStateKey, index + 1);
   }
 
   private getDistributionStoragePath(): string {
     // Use an empty string for the initial distribution for backwards compatibility.
-    const distributionFolderIndex = this._extensionContext.globalState.get(
+    const distributionFolderIndex = this.extensionContext.globalState.get(
       ExtensionSpecificDistributionManager._currentDistributionFolderIndexStateKey, 0) || '';
-    return path.join(this._extensionContext.globalStoragePath,
+    return path.join(this.extensionContext.globalStoragePath,
       ExtensionSpecificDistributionManager._currentDistributionFolderBaseName + distributionFolderIndex);
   }
 
@@ -425,17 +423,13 @@ class ExtensionSpecificDistributionManager {
   }
 
   private getInstalledRelease(): Release | undefined {
-    return this._extensionContext.globalState.get(ExtensionSpecificDistributionManager._installedReleaseStateKey);
+    return this.extensionContext.globalState.get(ExtensionSpecificDistributionManager._installedReleaseStateKey);
   }
 
   private async storeInstalledRelease(release: Release | undefined): Promise<void> {
-    await this._extensionContext.globalState.update(ExtensionSpecificDistributionManager._installedReleaseStateKey, release);
+    await this.extensionContext.globalState.update(ExtensionSpecificDistributionManager._installedReleaseStateKey, release);
   }
 
-  private readonly _config: DistributionConfig;
-  private readonly _extensionContext: ExtensionContext;
-  private readonly _versionRange: semver.Range;
-
   private static readonly _currentDistributionFolderBaseName = 'distribution';
   private static readonly _currentDistributionFolderIndexStateKey = 'distributionFolderIndex';
   private static readonly _installedReleaseStateKey = 'distributionRelease';
@@ -576,7 +570,7 @@ export async function extractZipArchive(archivePath: string, outPath: string): P
   }));
 }
 
-function codeQlLauncherName(): string {
+export function codeQlLauncherName(): string {
   return (os.platform() === 'win32') ? 'codeql.exe' : 'codeql';
 }
 
@@ -713,14 +707,14 @@ export async function getExecutableFromDirectory(directory: string, warnWhenNotF
     return alternateExpectedLauncherPath;
   }
   if (warnWhenNotFound) {
-    logger.log(`WARNING: Expected to find a CodeQL CLI executable at ${expectedLauncherPath} but one was not found. ` +
+    void logger.log(`WARNING: Expected to find a CodeQL CLI executable at ${expectedLauncherPath} but one was not found. ` +
       'Will try PATH.');
   }
   return undefined;
 }
 
 function warnDeprecatedLauncher() {
-  helpers.showAndLogWarningMessage(
+  void showAndLogWarningMessage(
     `The "${deprecatedCodeQlLauncherName()!}" launcher has been deprecated and will be removed in a future version. ` +
     `Please use "${codeQlLauncherName()}" instead. It is recommended to update to the latest CodeQL binaries.`
   );

extensions/ql-vscode/src/eval-log-tree-builder.ts

@@ -0,0 +1,67 @@
+import { ChildEvalLogTreeItem, EvalLogTreeItem } from './eval-log-viewer';
+import { EvalLogData as EvalLogData } from './pure/log-summary-parser';
+
+/** Builds the tree data for the evaluator log viewer for a single query run. */
+export default class EvalLogTreeBuilder {
+  private queryName: string;
+  private evalLogDataItems: EvalLogData[];
+
+  constructor(queryName: string, evaluatorLogDataItems: EvalLogData[]) {
+    this.queryName = queryName;
+    this.evalLogDataItems = evaluatorLogDataItems;
+  }
+
+  async getRoots(): Promise<EvalLogTreeItem[]> {
+    return await this.parseRoots();
+  }
+
+  private async parseRoots(): Promise<EvalLogTreeItem[]> {
+    const roots: EvalLogTreeItem[] = [];
+
+    // Once the viewer can show logs for multiple queries, there will be more than 1 item at the root
+    // level. For now, there will always be one root (the one query being shown).
+    const queryItem: EvalLogTreeItem = {
+      label: this.queryName,
+      children: [] // Will assign predicate items as children shortly.
+    };
+
+    // Display descriptive message when no data exists 
+    if (this.evalLogDataItems.length === 0) {
+      const noResultsItem: ChildEvalLogTreeItem = {
+        label: 'No predicates evaluated in this query run.',
+        parent: queryItem,
+        children: [],
+      };
+      queryItem.children.push(noResultsItem);
+    }
+
+    // For each predicate, create a TreeItem object with appropriate parents/children 
+    this.evalLogDataItems.forEach(logDataItem => {
+      const predicateLabel = `${logDataItem.predicateName} (${logDataItem.resultSize} tuples, ${logDataItem.millis} ms)`;
+      const predicateItem: ChildEvalLogTreeItem = {
+        label: predicateLabel,
+        parent: queryItem,
+        children: [] // Will assign pipeline items as children shortly.
+      };
+      for (const [pipelineName, steps] of Object.entries(logDataItem.ra)) {
+        const pipelineLabel = `Pipeline: ${pipelineName}`;
+        const pipelineItem: ChildEvalLogTreeItem = {
+          label: pipelineLabel,
+          parent: predicateItem,
+          children: [] // Will assign step items as children shortly.
+        };
+        predicateItem.children.push(pipelineItem);
+
+        pipelineItem.children = steps.map((step: string) => ({
+          label: step,
+          parent: pipelineItem,
+          children: []
+        }));
+      }
+      queryItem.children.push(predicateItem);
+    });
+
+    roots.push(queryItem);
+    return roots;
+  }
+}

extensions/ql-vscode/src/eval-log-viewer.ts

@@ -0,0 +1,92 @@
+import { window, TreeDataProvider, TreeView, TreeItem, ProviderResult, Event, EventEmitter, TreeItemCollapsibleState } from 'vscode';
+import { commandRunner } from './commandRunner';
+import { DisposableObject } from './pure/disposable-object';
+import { showAndLogErrorMessage } from './helpers';
+
+export interface EvalLogTreeItem {
+  label?: string;
+  children: ChildEvalLogTreeItem[];
+}
+
+export interface ChildEvalLogTreeItem extends EvalLogTreeItem {
+  parent: ChildEvalLogTreeItem | EvalLogTreeItem;
+}
+
+/** Provides data from parsed CodeQL evaluator logs to be rendered in a tree view. */
+class EvalLogDataProvider extends DisposableObject implements TreeDataProvider<EvalLogTreeItem> {
+  public roots: EvalLogTreeItem[] = [];
+
+  private _onDidChangeTreeData: EventEmitter<EvalLogTreeItem | undefined | null | void> = new EventEmitter<EvalLogTreeItem | undefined | null | void>();
+  readonly onDidChangeTreeData: Event<EvalLogTreeItem | undefined | null | void> = this._onDidChangeTreeData.event;
+
+  refresh(): void {
+    this._onDidChangeTreeData.fire();
+  }
+
+  getTreeItem(element: EvalLogTreeItem): TreeItem | Thenable<TreeItem> {
+    const state = element.children.length
+      ? TreeItemCollapsibleState.Collapsed
+      : TreeItemCollapsibleState.None;
+    const treeItem = new TreeItem(element.label || '', state);
+    treeItem.tooltip = `${treeItem.label} || ''}`;
+    return treeItem;
+  }
+
+  getChildren(element?: EvalLogTreeItem): ProviderResult<EvalLogTreeItem[]> {
+    // If no item is passed, return the root.
+    if (!element) {
+      return this.roots || [];
+    }
+    // Otherwise it is called with an existing item, to load its children.
+    return element.children;
+  }
+
+  getParent(element: ChildEvalLogTreeItem): ProviderResult<EvalLogTreeItem> {
+    return element.parent;
+  }
+}
+
+/** Manages a tree viewer of structured evaluator logs. */
+export class EvalLogViewer extends DisposableObject {
+  private treeView: TreeView<EvalLogTreeItem>;
+  private treeDataProvider: EvalLogDataProvider;
+
+  constructor() {
+    super();
+
+    this.treeDataProvider = new EvalLogDataProvider();
+    this.treeView = window.createTreeView('codeQLEvalLogViewer', {
+      treeDataProvider: this.treeDataProvider,
+      showCollapseAll: true
+    });
+
+    this.push(this.treeView);
+    this.push(this.treeDataProvider);
+    this.push(
+      commandRunner('codeQLEvalLogViewer.clear', async () => {
+        this.clear();
+      })
+    );
+  }
+
+  private clear(): void {
+    this.treeDataProvider.roots = [];
+    this.treeDataProvider.refresh();
+    this.treeView.message = undefined;
+  }
+
+  // Called when the Show Evaluator Log (UI) command is run on a new query.
+  updateRoots(roots: EvalLogTreeItem[]): void {
+    this.treeDataProvider.roots = roots;
+    this.treeDataProvider.refresh();
+
+    this.treeView.message = 'Viewer for query run:'; // Currently only one query supported at a time. 
+
+    // Handle error on reveal. This could happen if
+    // the tree view is disposed during the reveal.
+    this.treeView.reveal(roots[0], { focus: false })?.then(
+      () => { /**/ },
+      err => showAndLogErrorMessage(err)
+    );
+  }
+}

extensions/ql-vscode/src/helpers.ts

@@ -2,177 +2,29 @@ import * as fs from 'fs-extra';
 import * as glob from 'glob-promise';
 import * as yaml from 'js-yaml';
 import * as path from 'path';
+import * as tmp from 'tmp-promise';
 import {
-  CancellationToken,
   ExtensionContext,
-  ProgressOptions,
+  Uri,
   window as Window,
   workspace,
-  commands,
-  Disposable,
-  ProgressLocation
+  env
 } from 'vscode';
-import { CodeQLCliServer } from './cli';
+import { CodeQLCliServer, QlpacksInfo } from './cli';
+import { UserCancellationException } from './commandRunner';
 import { logger } from './logging';
+import { QueryMetadata } from './pure/interface-types';
 
-export class UserCancellationException extends Error {
-  /**
-   * @param message The error message
-   * @param silent If silent is true, then this exception will avoid showing a warning message to the user.
-   */
-  constructor(message?: string, public readonly silent = false) {
-    super(message);
+// Shared temporary folder for the extension.
+export const tmpDir = tmp.dirSync({ prefix: 'queries_', keep: false, unsafeCleanup: true });
+export const upgradesTmpDir = path.join(tmpDir.name, 'upgrades');
+fs.ensureDirSync(upgradesTmpDir);
+
+export const tmpDirDisposal = {
+  dispose: () => {
+    tmpDir.removeCallback();
   }
-}
-
-export interface ProgressUpdate {
-  /**
-   * The current step
-   */
-  step: number;
-  /**
-   * The maximum step. This *should* be constant for a single job.
-   */
-  maxStep: number;
-  /**
-   * The current progress message
-   */
-  message: string;
-}
-
-export type ProgressCallback = (p: ProgressUpdate) => void;
-
-/**
- * A task that handles command invocations from `commandRunner`
- * and includes a progress monitor.
- *
- *
- * Arguments passed to the command handler are passed along,
- * untouched to this `ProgressTask` instance.
- *
- * @param progress a progress handler function. Call this
- * function with a `ProgressUpdate` instance in order to
- * denote some progress being achieved on this task.
- * @param token a cencellation token
- * @param args arguments passed to this task passed on from
- * `commands.registerCommand`.
- */
-export type ProgressTask<R> = (
-  progress: ProgressCallback,
-  token: CancellationToken,
-  ...args: any[]
-) => Thenable<R>;
-
-/**
- * A task that handles command invocations from `commandRunner`.
- * Arguments passed to the command handler are passed along,
- * untouched to this `NoProgressTask` instance.
- *
- * @param args arguments passed to this task passed on from
- * `commands.registerCommand`.
- */
-type NoProgressTask = ((...args: any[]) => Promise<any>);
-
-/**
- * This mediates between the kind of progress callbacks we want to
- * write (where we *set* current progress position and give
- * `maxSteps`) and the kind vscode progress api expects us to write
- * (which increment progress by a certain amount out of 100%).
- *
- * Where possible, the `commandRunner` function below should be used
- * instead of this function. The commandRunner is meant for wrapping
- * top-level commands and provides error handling and other support
- * automatically.
- *
- * Only use this function if you need a progress monitor and the
- * control flow does not always come from a command (eg- during
- * extension activation, or from an internal language server
- * request).
- */
-export function withProgress<R>(
-  options: ProgressOptions,
-  task: ProgressTask<R>,
-  ...args: any[]
-): Thenable<R> {
-  let progressAchieved = 0;
-  return Window.withProgress(options,
-    (progress, token) => {
-      return task(p => {
-        const { message, step, maxStep } = p;
-        const increment = 100 * (step - progressAchieved) / maxStep;
-        progressAchieved = step;
-        progress.report({ message, increment });
-      }, token, ...args);
-    });
-}
-
-/**
- * A generic wrapper for command registration. This wrapper adds uniform error handling for commands.
- *
- * In this variant of the command runner, no progress monitor is used.
- *
- * @param commandId The ID of the command to register.
- * @param task The task to run. It is passed directly to `commands.registerCommand`. Any
- * arguments to the command handler are passed on to the task.
- */
-export function commandRunner(
-  commandId: string,
-  task: NoProgressTask,
-): Disposable {
-  return commands.registerCommand(commandId, async (...args: any[]) => {
-    try {
-      await task(...args);
-    } catch (e) {
-      if (e instanceof UserCancellationException) {
-        // User has cancelled this action manually
-        if (e.silent) {
-          logger.log(e.message);
-        } else {
-          showAndLogWarningMessage(e.message);
-        }
-      } else {
-        showAndLogErrorMessage(e.message || e);
-      }
-    }
-  });
-}
-
-/**
- * A generic wrapper for command registration.  This wrapper adds uniform error handling,
- * progress monitoring, and cancellation for commands.
- *
- * @param commandId The ID of the command to register.
- * @param task The task to run. It is passed directly to `commands.registerCommand`. Any
- * arguments to the command handler are passed on to the task after the progress callback
- * and cancellation token.
- * @param progressOptions Progress options to be sent to the progress monitor.
- */
-export function commandRunnerWithProgress<R>(
-  commandId: string,
-  task: ProgressTask<R>,
-  progressOptions: Partial<ProgressOptions>
-): Disposable {
-  return commands.registerCommand(commandId, async (...args: any[]) => {
-    const progressOptionsWithDefaults = {
-      location: ProgressLocation.Notification,
-      ...progressOptions
-    };
-    try {
-      await withProgress(progressOptionsWithDefaults, task, ...args);
-    } catch (e) {
-      if (e instanceof UserCancellationException) {
-        // User has cancelled this action manually
-        if (e.silent) {
-          logger.log(e.message);
-        } else {
-          showAndLogWarningMessage(e.message);
-        }
-      } else {
-        showAndLogErrorMessage(e.message || e);
-      }
-    }
-  });
-}
+};
 
 /**
  * Show an error message and log it to the console
@@ -180,15 +32,24 @@ export function commandRunnerWithProgress<R>(
  * @param message The message to show.
  * @param options.outputLogger The output logger that will receive the message
  * @param options.items A set of items that will be rendered as actions in the message.
+ * @param options.fullMessage An alternate message that is added to the log, but not displayed
+ *                           in the popup. This is useful for adding extra detail to the logs
+ *                           that would be too noisy for the popup.
  *
  * @return A promise that resolves to the selected item or undefined when being dismissed.
  */
 export async function showAndLogErrorMessage(message: string, {
   outputLogger = logger,
-  items = [] as string[]
+  items = [] as string[],
+  fullMessage = undefined as (string | undefined)
 } = {}): Promise<string | undefined> {
-  return internalShowAndLog(message, items, outputLogger, Window.showErrorMessage);
+  return internalShowAndLog(dropLinesExceptInitial(message), items, outputLogger, Window.showErrorMessage, fullMessage);
 }
+
+function dropLinesExceptInitial(message: string, n = 2) {
+  return message.toString().split(/\r?\n/).slice(0, n).join('\n');
+}
+
 /**
  * Show a warning message and log it to the console
  *
@@ -215,17 +76,23 @@ export async function showAndLogWarningMessage(message: string, {
  */
 export async function showAndLogInformationMessage(message: string, {
   outputLogger = logger,
-  items = [] as string[]
+  items = [] as string[],
+  fullMessage = ''
 } = {}): Promise<string | undefined> {
-  return internalShowAndLog(message, items, outputLogger, Window.showInformationMessage);
+  return internalShowAndLog(message, items, outputLogger, Window.showInformationMessage, fullMessage);
 }
 
 type ShowMessageFn = (message: string, ...items: string[]) => Thenable<string | undefined>;
 
-async function internalShowAndLog(message: string, items: string[], outputLogger = logger,
-  fn: ShowMessageFn): Promise<string | undefined> {
+async function internalShowAndLog(
+  message: string,
+  items: string[],
+  outputLogger = logger,
+  fn: ShowMessageFn,
+  fullMessage?: string
+): Promise<string | undefined> {
   const label = 'Show Log';
-  outputLogger.log(message);
+  void outputLogger.log(fullMessage || message);
   const result = await fn(message, label, ...items);
   if (result === label) {
     outputLogger.show();
@@ -235,17 +102,61 @@ async function internalShowAndLog(message: string, items: string[], outputLogger
 
 /**
  * Opens a modal dialog for the user to make a yes/no choice.
- * @param message The message to show.
  *
- * @return `true` if the user clicks 'Yes', `false` if the user clicks 'No' or cancels the dialog.
+ * @param message The message to show.
+ * @param modal If true (the default), show a modal dialog box, otherwise dialog is non-modal and can
+ *        be closed even if the user does not make a choice.
+ *
+ * @return
+ *  `true` if the user clicks 'Yes',
+ *  `false` if the user clicks 'No' or cancels the dialog,
+ *  `undefined` if the dialog is closed without the user making a choice.
  */
-export async function showBinaryChoiceDialog(message: string): Promise<boolean> {
+export async function showBinaryChoiceDialog(message: string, modal = true): Promise<boolean | undefined> {
   const yesItem = { title: 'Yes', isCloseAffordance: false };
   const noItem = { title: 'No', isCloseAffordance: true };
-  const chosenItem = await Window.showInformationMessage(message, { modal: true }, yesItem, noItem);
+  const chosenItem = await Window.showInformationMessage(message, { modal }, yesItem, noItem);
+  if (!chosenItem) {
+    return undefined;
+  }
   return chosenItem?.title === yesItem.title;
 }
 
+/**
+ * Opens a modal dialog for the user to make a yes/no choice.
+ *
+ * @param message The message to show.
+ * @param modal If true (the default), show a modal dialog box, otherwise dialog is non-modal and can
+ *        be closed even if the user does not make a choice.
+ *
+ * @return
+ *  `true` if the user clicks 'Yes',
+ *  `false` if the user clicks 'No' or cancels the dialog,
+ *  `undefined` if the dialog is closed without the user making a choice.
+ */
+export async function showBinaryChoiceWithUrlDialog(message: string, url: string): Promise<boolean | undefined> {
+  const urlItem = { title: 'More Information', isCloseAffordance: false };
+  const yesItem = { title: 'Yes', isCloseAffordance: false };
+  const noItem = { title: 'No', isCloseAffordance: true };
+  let chosenItem;
+
+  // Keep the dialog open as long as the user is clicking the 'more information' option.
+  // To prevent an infinite loop, if the user clicks 'more information' 5 times, close the dialog and return cancelled
+  let count = 0;
+  do {
+    chosenItem = await Window.showInformationMessage(message, { modal: true }, urlItem, yesItem, noItem);
+    if (chosenItem === urlItem) {
+      await env.openExternal(Uri.parse(url, true));
+    }
+    count++;
+  } while (chosenItem === urlItem && count < 5);
+
+  if (!chosenItem || chosenItem.title === urlItem.title) {
+    return undefined;
+  }
+  return chosenItem.title === yesItem.title;
+}
+
 /**
  * Show an information message with a customisable action.
  * @param message The message to show.
@@ -358,40 +269,78 @@ function createRateLimitedResult(): RateLimitedResult {
   };
 }
 
-
-export type DatasetFolderInfo = {
-  dbscheme: string;
-  qlpack: string;
+export interface QlPacksForLanguage {
+  /** The name of the pack containing the dbscheme. */
+  dbschemePack: string;
+  /** `true` if `dbschemePack` is a library pack. */
+  dbschemePackIsLibraryPack: boolean;
+  /**
+   * The name of the corresponding standard query pack.
+   * Only defined if `dbschemePack` is a library pack.
+   */
+  queryPack?: string;
 }
 
-export async function getQlPackForDbscheme(cliServer: CodeQLCliServer, dbschemePath: string): Promise<string> {
-  const qlpacks = await cliServer.resolveQlpacks(getOnDiskWorkspaceFolders());
-  const packs: { packDir: string | undefined; packName: string }[] =
-    Object.entries(qlpacks).map(([packName, dirs]) => {
-      if (dirs.length < 1) {
-        logger.log(`In getQlPackFor ${dbschemePath}, qlpack ${packName} has no directories`);
-        return { packName, packDir: undefined };
-      }
-      if (dirs.length > 1) {
-        logger.log(`In getQlPackFor ${dbschemePath}, qlpack ${packName} has more than one directory; arbitrarily choosing the first`);
-      }
-      return {
-        packName,
-        packDir: dirs[0]
-      };
-    });
+interface QlPackWithPath {
+  packName: string;
+  packDir: string | undefined;
+}
+
+async function findDbschemePack(packs: QlPackWithPath[], dbschemePath: string): Promise<{ name: string; isLibraryPack: boolean; }> {
   for (const { packDir, packName } of packs) {
     if (packDir !== undefined) {
-      const qlpack = yaml.safeLoad(await fs.readFile(path.join(packDir, 'qlpack.yml'), 'utf8')) as { dbscheme: string };
+      const qlpack = yaml.load(await fs.readFile(path.join(packDir, 'qlpack.yml'), 'utf8')) as { dbscheme?: string; library?: boolean; };
       if (qlpack.dbscheme !== undefined && path.basename(qlpack.dbscheme) === path.basename(dbschemePath)) {
-        return packName;
+        return {
+          name: packName,
+          isLibraryPack: qlpack.library === true
+        };
       }
     }
   }
   throw new Error(`Could not find qlpack file for dbscheme ${dbschemePath}`);
 }
 
-export async function resolveDatasetFolder(cliServer: CodeQLCliServer, datasetFolder: string): Promise<DatasetFolderInfo> {
+function findStandardQueryPack(qlpacks: QlpacksInfo, dbschemePackName: string): string | undefined {
+  const matches = dbschemePackName.match(/^codeql\/(?<language>[a-z]+)-all$/);
+  if (matches) {
+    const queryPackName = `codeql/${matches.groups!.language}-queries`;
+    if (qlpacks[queryPackName] !== undefined) {
+      return queryPackName;
+    }
+  }
+
+  // Either the dbscheme pack didn't look like one where the queries might be in the query pack, or
+  // no query pack was found in the search path. Either is OK.
+  return undefined;
+}
+
+export async function getQlPackForDbscheme(cliServer: CodeQLCliServer, dbschemePath: string): Promise<QlPacksForLanguage> {
+  const qlpacks = await cliServer.resolveQlpacks(getOnDiskWorkspaceFolders());
+  const packs: QlPackWithPath[] =
+    Object.entries(qlpacks).map(([packName, dirs]) => {
+      if (dirs.length < 1) {
+        void logger.log(`In getQlPackFor ${dbschemePath}, qlpack ${packName} has no directories`);
+        return { packName, packDir: undefined };
+      }
+      if (dirs.length > 1) {
+        void logger.log(`In getQlPackFor ${dbschemePath}, qlpack ${packName} has more than one directory; arbitrarily choosing the first`);
+      }
+      return {
+        packName,
+        packDir: dirs[0]
+      };
+    });
+  const dbschemePack = await findDbschemePack(packs, dbschemePath);
+  const queryPack = dbschemePack.isLibraryPack ? findStandardQueryPack(qlpacks, dbschemePack.name) : undefined;
+  return {
+    dbschemePack: dbschemePack.name,
+    dbschemePackIsLibraryPack: dbschemePack.isLibraryPack,
+    queryPack
+  };
+}
+
+export async function getPrimaryDbscheme(datasetFolder: string): Promise<string> {
   const dbschemes = await glob(path.join(datasetFolder, '*.dbscheme'));
 
   if (dbschemes.length < 1) {
@@ -400,31 +349,30 @@ export async function resolveDatasetFolder(cliServer: CodeQLCliServer, datasetFo
 
   dbschemes.sort();
   const dbscheme = dbschemes[0];
-  if (dbschemes.length > 1) {
-    Window.showErrorMessage(`Found multiple dbschemes in ${datasetFolder} during quick query; arbitrarily choosing the first, ${dbscheme}, to decide what library to use.`);
-  }
 
-  const qlpack = await getQlPackForDbscheme(cliServer, dbscheme);
-  return { dbscheme, qlpack };
+  if (dbschemes.length > 1) {
+    void Window.showErrorMessage(`Found multiple dbschemes in ${datasetFolder} during quick query; arbitrarily choosing the first, ${dbscheme}, to decide what library to use.`);
+  }
+  return dbscheme;
 }
 
 /**
  * A cached mapping from strings to value of type U.
  */
 export class CachedOperation<U> {
-  private readonly operation: (t: string) => Promise<U>;
+  private readonly operation: (t: string, ...args: any[]) => Promise<U>;
   private readonly cached: Map<string, U>;
   private readonly lru: string[];
   private readonly inProgressCallbacks: Map<string, [(u: U) => void, (reason?: any) => void][]>;
 
-  constructor(operation: (t: string) => Promise<U>, private cacheSize = 100) {
+  constructor(operation: (t: string, ...args: any[]) => Promise<U>, private cacheSize = 100) {
     this.operation = operation;
     this.lru = [];
     this.inProgressCallbacks = new Map<string, [(u: U) => void, (reason?: any) => void][]>();
     this.cached = new Map<string, U>();
   }
 
-  async get(t: string): Promise<U> {
+  async get(t: string, ...args: any[]): Promise<U> {
     // Try and retrieve from the cache
     const fromCache = this.cached.get(t);
     if (fromCache !== undefined) {
@@ -445,7 +393,7 @@ export class CachedOperation<U> {
     const callbacks: [(u: U) => void, (reason?: any) => void][] = [];
     this.inProgressCallbacks.set(t, callbacks);
     try {
-      const result = await this.operation(t);
+      const result = await this.operation(t, ...args);
       callbacks.forEach(f => f[0](result));
       this.inProgressCallbacks.delete(t);
       if (this.lru.length > this.cacheSize) {
@@ -464,3 +412,183 @@ export class CachedOperation<U> {
     }
   }
 }
+
+
+
+/**
+ * The following functions al heuristically determine metadata about databases.
+ */
+
+/**
+ * Note that this heuristic is only being used for backwards compatibility with
+ * CLI versions before the langauge name was introduced to dbInfo. Features
+ * that do not require backwards compatibility should call
+ * `cli.CodeQLCliServer.resolveDatabase` and use the first entry in the
+ * `languages` property.
+ *
+ * @see cli.CliVersionConstraint.supportsLanguageName
+ * @see cli.CodeQLCliServer.resolveDatabase
+ */
+export const dbSchemeToLanguage = {
+  'semmlecode.javascript.dbscheme': 'javascript',
+  'semmlecode.cpp.dbscheme': 'cpp',
+  'semmlecode.dbscheme': 'java',
+  'semmlecode.python.dbscheme': 'python',
+  'semmlecode.csharp.dbscheme': 'csharp',
+  'go.dbscheme': 'go',
+  'ruby.dbscheme': 'ruby'
+};
+
+export const languageToDbScheme = Object.entries(dbSchemeToLanguage).reduce((acc, [k, v]) => {
+  acc[v] = k;
+  return acc;
+}, {} as { [k: string]: string });
+
+
+/**
+ * Returns the initial contents for an empty query, based on the language of the selected
+ * databse.
+ *
+ * First try to use the given language name. If that doesn't exist, try to infer it based on
+ * dbscheme. Otherwise return no import statement.
+ *
+ * @param language the database language or empty string if unknown
+ * @param dbscheme path to the dbscheme file
+ *
+ * @returns an import and empty select statement appropriate for the selected language
+ */
+export function getInitialQueryContents(language: string, dbscheme: string) {
+  if (!language) {
+    const dbschemeBase = path.basename(dbscheme) as keyof typeof dbSchemeToLanguage;
+    language = dbSchemeToLanguage[dbschemeBase];
+  }
+
+  return language
+    ? `import ${language}\n\nselect ""`
+    : 'select ""';
+}
+
+/**
+ * Heuristically determines if the directory passed in corresponds
+ * to a database root. A database root is a directory that contains
+ * a codeql-database.yml or (historically) a .dbinfo file. It also
+ * contains a folder starting with `db-`.
+ */
+export async function isLikelyDatabaseRoot(maybeRoot: string) {
+  const [a, b, c] = (await Promise.all([
+    // databases can have either .dbinfo or codeql-database.yml.
+    fs.pathExists(path.join(maybeRoot, '.dbinfo')),
+    fs.pathExists(path.join(maybeRoot, 'codeql-database.yml')),
+
+    // they *must* have a db-{language} folder
+    glob('db-*/', { cwd: maybeRoot })
+  ]));
+
+  return ((a || b) && c.length > 0);
+}
+
+/**
+ * A language folder is any folder starting with `db-` that is itself not a database root.
+ */
+export async function isLikelyDbLanguageFolder(dbPath: string) {
+  return path.basename(dbPath).startsWith('db-') && !(await isLikelyDatabaseRoot(dbPath));
+}
+
+/**
+ * Finds the language that a query targets.
+ * If it can't be autodetected, prompt the user to specify the language manually.
+ */
+export async function findLanguage(
+  cliServer: CodeQLCliServer,
+  queryUri: Uri | undefined
+): Promise<string | undefined> {
+  const uri = queryUri || Window.activeTextEditor?.document.uri;
+  if (uri !== undefined) {
+    try {
+      const queryInfo = await cliServer.resolveQueryByLanguage(getOnDiskWorkspaceFolders(), uri);
+      const language = (Object.keys(queryInfo.byLanguage))[0];
+      void logger.log(`Detected query language: ${language}`);
+      return language;
+    } catch (e) {
+      void logger.log('Could not autodetect query language. Select language manually.');
+    }
+  }
+
+  // will be undefined if user cancels the quick pick.
+  return await askForLanguage(cliServer, false);
+}
+
+export async function askForLanguage(cliServer: CodeQLCliServer, throwOnEmpty = true): Promise<string | undefined> {
+  const language = await Window.showQuickPick(
+    await cliServer.getSupportedLanguages(),
+    { placeHolder: 'Select target language for your query', ignoreFocusOut: true }
+  );
+  if (!language) {
+    // This only happens if the user cancels the quick pick.
+    if (throwOnEmpty) {
+      throw new UserCancellationException('Cancelled.');
+    } else {
+      void showAndLogErrorMessage('Language not found. Language must be specified manually.');
+    }
+  }
+  return language;
+}
+
+/**
+ * Gets metadata for a query, if it exists.
+ * @param cliServer The CLI server.
+ * @param queryPath The path to the query.
+ * @returns A promise that resolves to the query metadata, if available.
+ */
+export async function tryGetQueryMetadata(cliServer: CodeQLCliServer, queryPath: string): Promise<QueryMetadata | undefined> {
+  try {
+    return await cliServer.resolveMetadata(queryPath);
+  } catch (e) {
+    // Ignore errors and provide no metadata.
+    void logger.log(`Couldn't resolve metadata for ${queryPath}: ${e}`);
+    return;
+  }
+}
+
+/**
+ * Creates a file in the query directory that indicates when this query was created.
+ * This is important for keeping track of when queries should be removed.
+ *
+ * @param queryPath The directory that will containt all files relevant to a query result.
+ * It does not need to exist.
+ */
+export async function createTimestampFile(storagePath: string) {
+  const timestampPath = path.join(storagePath, 'timestamp');
+  await fs.ensureDir(storagePath);
+  await fs.writeFile(timestampPath, Date.now().toString(), 'utf8');
+}
+
+
+/**
+ * Recursively walk a directory and return the full path to all files found.
+ * Symbolic links are ignored.
+ *
+ * @param dir the directory to walk
+ *
+ * @return An iterator of the full path to all files recursively found in the directory.
+ */
+export async function* walkDirectory(dir: string): AsyncIterableIterator<string> {
+  const seenFiles = new Set<string>();
+  for await (const d of await fs.opendir(dir)) {
+    const entry = path.join(dir, d.name);
+    seenFiles.add(entry);
+    if (d.isDirectory()) {
+      yield* walkDirectory(entry);
+    } else if (d.isFile()) {
+      yield entry;
+    }
+  }
+}
+
+/**
+ * Pluralizes a word.
+ * Example: Returns "N repository" if N is one, "N repositories" otherwise.
+ */
+export function pluralize(numItems: number | undefined, singular: string, plural: string): string {
+  return numItems ? `${numItems} ${numItems === 1 ? singular : plural}` : '';
+}

extensions/ql-vscode/src/history-item-label-provider.ts

@@ -0,0 +1,118 @@
+import { env } from 'vscode';
+import * as path from 'path';
+import { QueryHistoryConfig } from './config';
+import { LocalQueryInfo } from './query-results';
+import { getRawQueryName, QueryHistoryInfo } from './query-history-info';
+import { RemoteQueryHistoryItem } from './remote-queries/remote-query-history-item';
+import { pluralize } from './helpers';
+import { VariantAnalysisHistoryItem } from './remote-queries/variant-analysis-history-item';
+import { assertNever } from './pure/helpers-pure';
+
+interface InterpolateReplacements {
+  t: string; // Start time
+  q: string; // Query name
+  d: string; // Database/Controller repo name
+  r: string; // Result count/Empty
+  s: string; // Status
+  f: string; // Query file name
+  '%': '%'; // Percent sign
+}
+
+export class HistoryItemLabelProvider {
+  constructor(private config: QueryHistoryConfig) {
+    /**/
+  }
+
+  getLabel(item: QueryHistoryInfo) {
+    let replacements: InterpolateReplacements;
+    switch (item.t) {
+      case 'local':
+        replacements = this.getLocalInterpolateReplacements(item);
+        break;
+      case 'remote':
+        replacements = this.getRemoteInterpolateReplacements(item);
+        break;
+      case 'variant-analysis':
+        replacements = this.getVariantAnalysisInterpolateReplacements(item);
+        break;
+      default:
+        assertNever(item);
+    }
+
+    const rawLabel = item.userSpecifiedLabel ?? (this.config.format || '%q');
+
+    return this.interpolate(rawLabel, replacements);
+  }
+
+  /**
+   * If there is a user-specified label for this query, interpolate and use that.
+   * Otherwise, use the raw name of this query.
+   *
+   * @returns the name of the query, unless there is a custom label for this query.
+   */
+  getShortLabel(item: QueryHistoryInfo): string {
+    return item.userSpecifiedLabel
+      ? this.getLabel(item)
+      : getRawQueryName(item);
+  }
+
+
+  private interpolate(rawLabel: string, replacements: InterpolateReplacements): string {
+    const label = rawLabel.replace(/%(.)/g, (match, key: keyof InterpolateReplacements) => {
+      const replacement = replacements[key];
+      return replacement !== undefined ? replacement : match;
+    });
+
+    return label.replace(/\s+/g, ' ');
+  }
+
+  private getLocalInterpolateReplacements(item: LocalQueryInfo): InterpolateReplacements {
+    const { resultCount = 0, statusString = 'in progress' } = item.completedQuery || {};
+    return {
+      t: item.startTime,
+      q: item.getQueryName(),
+      d: item.initialInfo.databaseInfo.name,
+      r: `(${resultCount} results)`,
+      s: statusString,
+      f: item.getQueryFileName(),
+      '%': '%',
+    };
+  }
+
+  // Return the number of repositories queried if available. Otherwise, use the controller repository name.
+  private buildRepoLabel(item: RemoteQueryHistoryItem): string {
+    const repositoryCount = item.remoteQuery.repositoryCount;
+
+    if (repositoryCount) {
+      return pluralize(repositoryCount, 'repository', 'repositories');
+    }
+
+    return `${item.remoteQuery.controllerRepository.owner}/${item.remoteQuery.controllerRepository.name}`;
+  }
+
+  private getRemoteInterpolateReplacements(item: RemoteQueryHistoryItem): InterpolateReplacements {
+    const resultCount = item.resultCount ? `(${pluralize(item.resultCount, 'result', 'results')})` : '';
+    return {
+      t: new Date(item.remoteQuery.executionStartTime).toLocaleString(env.language),
+      q: `${item.remoteQuery.queryName} (${item.remoteQuery.language})`,
+      d: this.buildRepoLabel(item),
+      r: resultCount,
+      s: item.status,
+      f: path.basename(item.remoteQuery.queryFilePath),
+      '%': '%'
+    };
+  }
+
+  private getVariantAnalysisInterpolateReplacements(item: VariantAnalysisHistoryItem): InterpolateReplacements {
+    const resultCount = item.resultCount ? `(${pluralize(item.resultCount, 'result', 'results')})` : '';
+    return {
+      t: new Date(item.variantAnalysis.executionStartTime).toLocaleString(env.language),
+      q: `${item.variantAnalysis.query.name} (${item.variantAnalysis.query.language})`,
+      d: 'TODO',
+      r: resultCount,
+      s: item.status,
+      f: path.basename(item.variantAnalysis.query.filePath),
+      '%': '%',
+    };
+  }
+}

extensions/ql-vscode/src/interface-utils.ts

@@ -1,8 +1,10 @@
 import * as crypto from 'crypto';
+import * as os from 'os';
 import {
   Uri,
   Location,
   Range,
+  ExtensionContext,
   WebviewPanel,
   Webview,
   workspace,
@@ -70,7 +72,7 @@ function resolveFivePartLocation(
     Math.max(0, loc.startLine - 1),
     Math.max(0, loc.startColumn - 1),
     Math.max(0, loc.endLine - 1),
-    Math.max(0, loc.endColumn)
+    Math.max(1, loc.endColumn)
   );
 
   return new Location(databaseItem.resolveSourceFile(loc.uri), range);
@@ -110,20 +112,54 @@ export function tryResolveLocation(
   }
 }
 
+export type WebviewView = 'results' | 'compare' | 'remote-queries' | 'variant-analysis';
+
+export interface WebviewMessage {
+  t: string;
+}
+
 /**
  * Returns HTML to populate the given webview.
  * Uses a content security policy that only loads the given script.
  */
 export function getHtmlForWebview(
+  ctx: ExtensionContext,
   webview: Webview,
-  scriptUriOnDisk: Uri,
-  stylesheetUriOnDisk: Uri
+  view: WebviewView,
+  {
+    allowInlineStyles,
+  }: {
+    allowInlineStyles?: boolean;
+  } = {
+      allowInlineStyles: false,
+    }
 ): string {
+  const scriptUriOnDisk = Uri.file(
+    ctx.asAbsolutePath('out/webview.js')
+  );
+
+  const stylesheetUrisOnDisk = [
+    Uri.file(ctx.asAbsolutePath('out/webview.css'))
+  ];
+
   // Convert the on-disk URIs into webview URIs.
   const scriptWebviewUri = webview.asWebviewUri(scriptUriOnDisk);
-  const stylesheetWebviewUri = webview.asWebviewUri(stylesheetUriOnDisk);
+  const stylesheetWebviewUris = stylesheetUrisOnDisk.map(stylesheetUriOnDisk =>
+    webview.asWebviewUri(stylesheetUriOnDisk));
+
   // Use a nonce in the content security policy to uniquely identify the above resources.
   const nonce = getNonce();
+
+  const stylesheetsHtmlLines = allowInlineStyles
+    ? stylesheetWebviewUris.map(uri => createStylesLinkWithoutNonce(uri))
+    : stylesheetWebviewUris.map(uri => createStylesLinkWithNonce(nonce, uri));
+
+  const styleSrc = allowInlineStyles
+    ? `${webview.cspSource} vscode-file: 'unsafe-inline'`
+    : `'nonce-${nonce}'`;
+
+  const fontSrc = webview.cspSource;
+
   /*
    * Content security policy:
    * default-src: allow nothing by default.
@@ -136,11 +172,11 @@ export function getHtmlForWebview(
 <html>
   <head>
     <meta http-equiv="Content-Security-Policy"
-          content="default-src 'none'; script-src 'nonce-${nonce}'; style-src 'nonce-${nonce}'; connect-src ${webview.cspSource};">
-    <link nonce="${nonce}" rel="stylesheet" href="${stylesheetWebviewUri}">
+          content="default-src 'none'; script-src 'nonce-${nonce}'; font-src ${fontSrc}; style-src ${styleSrc}; connect-src ${webview.cspSource};">
+        ${stylesheetsHtmlLines.join(`    ${os.EOL}`)}
   </head>
   <body>
-    <div id=root>
+    <div id=root data-view="${view}">
     </div>
       <script nonce="${nonce}" src="${scriptWebviewUri}">
     </script>
@@ -224,15 +260,23 @@ export async function jumpToLocation(
     } catch (e) {
       if (e instanceof Error) {
         if (e.message.match(/File not found/)) {
-          Window.showErrorMessage(
+          void Window.showErrorMessage(
             'Original file of this result is not in the database\'s source archive.'
           );
         } else {
-          logger.log(`Unable to handleMsgFromView: ${e.message}`);
+          void logger.log(`Unable to handleMsgFromView: ${e.message}`);
         }
       } else {
-        logger.log(`Unable to handleMsgFromView: ${e}`);
+        void logger.log(`Unable to handleMsgFromView: ${e}`);
       }
     }
   }
 }
+
+function createStylesLinkWithNonce(nonce: string, uri: Uri): string {
+  return `<link nonce="${nonce}" rel="stylesheet" href="${uri}">`;
+}
+
+function createStylesLinkWithoutNonce(uri: Uri): string {
+  return `<link rel="stylesheet" href="${uri}">`;
+}

extensions/ql-vscode/src/interface.ts

@@ -1,6 +1,4 @@
-import * as path from 'path';
 import * as Sarif from 'sarif';
-import { DisposableObject } from './vscode-utils/disposable-object';
 import * as vscode from 'vscode';
 import {
   Diagnostic,
@@ -15,7 +13,7 @@ import * as cli from './cli';
 import { CodeQLCliServer } from './cli';
 import { DatabaseEventKind, DatabaseItem, DatabaseManager } from './databases';
 import { showAndLogErrorMessage } from './helpers';
-import { assertNever } from './pure/helpers-pure';
+import { assertNever, getErrorMessage, getErrorStack } from './pure/helpers-pure';
 import {
   FromResultsViewMsg,
   Interpretation,
@@ -27,26 +25,28 @@ import {
   InterpretedResultsSortState,
   SortDirection,
   ALERTS_TABLE_NAME,
+  GRAPH_TABLE_NAME,
   RawResultsSortState,
 } from './pure/interface-types';
 import { Logger } from './logging';
-import { commandRunner } from './helpers';
-import * as messages from './pure/messages';
-import { CompletedQuery, interpretResults } from './query-results';
-import { QueryInfo, tmpDir } from './run-queries';
+import { commandRunner } from './commandRunner';
+import { CompletedQueryInfo, interpretResultsSarif, interpretGraphResults } from './query-results';
+import { QueryEvaluationInfo } from './run-queries-shared';
 import { parseSarifLocation, parseSarifPlainTextMessage } from './pure/sarif-utils';
 import {
   WebviewReveal,
   fileUriToWebviewUri,
   tryResolveLocation,
-  getHtmlForWebview,
   shownLocationDecoration,
   shownLocationLineDecoration,
   jumpToLocation,
 } from './interface-utils';
 import { getDefaultResultSetName, ParsedResultSets } from './pure/interface-types';
 import { RawResultSet, transformBqrsResultSet, ResultSetSchema } from './pure/bqrs-cli-types';
+import { AbstractWebview, WebviewPanelConfig } from './abstract-webview';
 import { PAGE_SIZE } from './config';
+import { CompletedLocalQueryInfo } from './query-results';
+import { HistoryItemLabelProvider } from './history-item-label-provider';
 
 /**
  * interface.ts
@@ -87,20 +87,41 @@ function sortInterpretedResults(
   }
 }
 
-function numPagesOfResultSet(resultSet: RawResultSet): number {
-  return Math.ceil(resultSet.schema.rows / PAGE_SIZE.getValue<number>());
+function interpretedPageSize(interpretation: Interpretation | undefined): number {
+  if (interpretation?.data.t == 'GraphInterpretationData') {
+    // Graph views always have one result per page.
+    return 1;
+  }
+  return PAGE_SIZE.getValue<number>();
+}
+
+function numPagesOfResultSet(resultSet: RawResultSet, interpretation?: Interpretation): number {
+  const pageSize = interpretedPageSize(interpretation);
+
+  const n = interpretation?.data.t == 'GraphInterpretationData'
+    ? interpretation.data.dot.length
+    : resultSet.schema.rows;
+
+  return Math.ceil(n / pageSize);
 }
 
 function numInterpretedPages(interpretation: Interpretation | undefined): number {
-  return Math.ceil((interpretation?.sarif.runs[0].results?.length || 0) / PAGE_SIZE.getValue<number>());
+  if (!interpretation) {
+    return 0;
+  }
+
+  const pageSize = interpretedPageSize(interpretation);
+
+  const n = interpretation.data.t == 'GraphInterpretationData'
+    ? interpretation.data.dot.length
+    : interpretation.data.runs[0].results?.length || 0;
+
+  return Math.ceil(n / pageSize);
 }
 
-export class InterfaceManager extends DisposableObject {
-  private _displayedQuery?: CompletedQuery;
+export class ResultsView extends AbstractWebview<IntoResultsViewMsg, FromResultsViewMsg> {
+  private _displayedQuery?: CompletedLocalQueryInfo;
   private _interpretation?: Interpretation;
-  private _panel: vscode.WebviewPanel | undefined;
-  private _panelLoaded = false;
-  private _panelLoadedCallBacks: (() => void)[] = [];
 
   private readonly _diagnosticCollection = languages.createDiagnosticCollection(
     'codeql-query-results'
@@ -110,16 +131,17 @@ export class InterfaceManager extends DisposableObject {
     public ctx: vscode.ExtensionContext,
     private databaseManager: DatabaseManager,
     public cliServer: CodeQLCliServer,
-    public logger: Logger
+    public logger: Logger,
+    private labelProvider: HistoryItemLabelProvider
   ) {
-    super();
+    super(ctx);
     this.push(this._diagnosticCollection);
     this.push(
       vscode.window.onDidChangeTextEditorSelection(
         this.handleSelectionChange.bind(this)
       )
     );
-    logger.log('Registering path-step navigation commands.');
+    void logger.log('Registering path-step navigation commands.');
     this.push(
       commandRunner(
         'codeQLQueryResults.nextPathStep',
@@ -137,77 +159,132 @@ export class InterfaceManager extends DisposableObject {
       this.databaseManager.onDidChangeDatabaseItem(({ kind }) => {
         if (kind === DatabaseEventKind.Remove) {
           this._diagnosticCollection.clear();
-          this.postMessage({
-            t: 'untoggleShowProblems'
-          });
+          if (this.isShowingPanel) {
+            void this.postMessage({
+              t: 'untoggleShowProblems'
+            });
+          }
         }
       })
     );
   }
 
   async navigatePathStep(direction: number): Promise<void> {
-    this.postMessage({ t: 'navigatePath', direction });
+    await this.postMessage({ t: 'navigatePath', direction });
   }
 
-  // Returns the webview panel, creating it if it doesn't already
-  // exist.
-  getPanel(): vscode.WebviewPanel {
-    if (this._panel == undefined) {
-      const { ctx } = this;
-      const panel = (this._panel = Window.createWebviewPanel(
-        'resultsView', // internal name
-        'CodeQL Query Results', // user-visible name
-        { viewColumn: vscode.ViewColumn.Beside, preserveFocus: true },
-        {
-          enableScripts: true,
-          enableFindWidget: true,
-          retainContextWhenHidden: true,
-          localResourceRoots: [
-            vscode.Uri.file(tmpDir.name),
-            vscode.Uri.file(path.join(this.ctx.extensionPath, 'out'))
-          ]
+  protected getPanelConfig(): WebviewPanelConfig {
+    return {
+      viewId: 'resultsView',
+      title: 'CodeQL Query Results',
+      viewColumn: this.chooseColumnForWebview(),
+      preserveFocus: true,
+      view: 'results',
+    };
+  }
+
+  protected onPanelDispose(): void {
+    this._displayedQuery = undefined;
+  }
+
+  protected async onMessage(msg: FromResultsViewMsg): Promise<void> {
+    try {
+      switch (msg.t) {
+        case 'viewLoaded':
+          this.onWebViewLoaded();
+          break;
+        case 'viewSourceFile': {
+          await jumpToLocation(msg, this.databaseManager, this.logger);
+          break;
         }
-      ));
-      this._panel.onDidDispose(
-        () => {
-          this._panel = undefined;
-          this._displayedQuery = undefined;
-        },
-        null,
-        ctx.subscriptions
-      );
-      const scriptPathOnDisk = vscode.Uri.file(
-        ctx.asAbsolutePath('out/resultsView.js')
-      );
-      const stylesheetPathOnDisk = vscode.Uri.file(
-        ctx.asAbsolutePath('out/resultsView.css')
-      );
-      panel.webview.html = getHtmlForWebview(
-        panel.webview,
-        scriptPathOnDisk,
-        stylesheetPathOnDisk
-      );
-      panel.webview.onDidReceiveMessage(
-        async (e) => this.handleMsgFromView(e),
-        undefined,
-        ctx.subscriptions
-      );
+        case 'toggleDiagnostics': {
+          if (msg.visible) {
+            const databaseItem = this.databaseManager.findDatabaseItem(
+              Uri.parse(msg.databaseUri)
+            );
+            if (databaseItem !== undefined) {
+              await this.showResultsAsDiagnostics(
+                msg.origResultsPaths,
+                msg.metadata,
+                databaseItem
+              );
+            }
+          } else {
+            // TODO: Only clear diagnostics on the same database.
+            this._diagnosticCollection.clear();
+          }
+          break;
+        }
+        case 'changeSort':
+          await this.changeRawSortState(msg.resultSetName, msg.sortState);
+          break;
+        case 'changeInterpretedSort':
+          await this.changeInterpretedSortState(msg.sortState);
+          break;
+        case 'changePage':
+          if (msg.selectedTable === ALERTS_TABLE_NAME || msg.selectedTable === GRAPH_TABLE_NAME) {
+            await this.showPageOfInterpretedResults(msg.pageNumber);
+          }
+          else {
+            await this.showPageOfRawResults(
+              msg.selectedTable,
+              msg.pageNumber,
+              // When we are in an unsorted state, we guarantee that
+              // sortedResultsInfo doesn't have an entry for the current
+              // result set. Use this to determine whether or not we use
+              // the sorted bqrs file.
+              !!this._displayedQuery?.completedQuery.sortedResultsInfo[msg.selectedTable]
+            );
+          }
+          break;
+        case 'openFile':
+          await this.openFile(msg.filePath);
+          break;
+        default:
+          assertNever(msg);
+      }
+    } catch (e) {
+      void showAndLogErrorMessage(getErrorMessage(e), {
+        fullMessage: getErrorStack(e)
+      });
     }
-    return this._panel;
+  }
+
+  /**
+   * Choose where to open the webview.
+   *
+   * If there is a single view column, then open beside it.
+   * If there are multiple view columns, then open beside the active column,
+   * unless the active editor is the last column. In this case, open in the first column.
+   *
+   * The goal is to avoid opening new columns when there already are two columns open.
+   */
+  private chooseColumnForWebview(): vscode.ViewColumn {
+    // This is not a great way to determine the number of view columns, but I
+    // can't find a vscode API that does it any better.
+    // Here, iterate through all the visible editors and determine the max view column.
+    // This won't work if the largest view column is empty.
+    const colCount = Window.visibleTextEditors.reduce((maxVal, editor) =>
+      Math.max(maxVal, Number.parseInt(editor.viewColumn?.toFixed() || '0', 10)), 0);
+    if (colCount <= 1) {
+      return vscode.ViewColumn.Beside;
+    }
+    const activeViewColumnNum = Number.parseInt(Window.activeTextEditor?.viewColumn?.toFixed() || '0', 10);
+    return activeViewColumnNum === colCount ? vscode.ViewColumn.One : vscode.ViewColumn.Beside;
   }
 
   private async changeInterpretedSortState(
     sortState: InterpretedResultsSortState | undefined
   ): Promise<void> {
     if (this._displayedQuery === undefined) {
-      showAndLogErrorMessage(
+      void showAndLogErrorMessage(
         'Failed to sort results since evaluation info was unknown.'
       );
       return;
     }
     // Notify the webview that it should expect new results.
     await this.postMessage({ t: 'resultsUpdating' });
-    this._displayedQuery.updateInterpretedSortState(sortState);
+    await this._displayedQuery.completedQuery.updateInterpretedSortState(sortState);
     await this.showResults(this._displayedQuery, WebviewReveal.NotForced, true);
   }
 
@@ -216,14 +293,14 @@ export class InterfaceManager extends DisposableObject {
     sortState: RawResultsSortState | undefined
   ): Promise<void> {
     if (this._displayedQuery === undefined) {
-      showAndLogErrorMessage(
+      void showAndLogErrorMessage(
         'Failed to sort results since evaluation info was unknown.'
       );
       return;
     }
     // Notify the webview that it should expect new results.
     await this.postMessage({ t: 'resultsUpdating' });
-    await this._displayedQuery.updateSortState(
+    await this._displayedQuery.completedQuery.updateSortState(
       this.cliServer,
       resultSetName,
       sortState
@@ -235,79 +312,9 @@ export class InterfaceManager extends DisposableObject {
     await this.showPageOfRawResults(resultSetName, 0, true);
   }
 
-  private async handleMsgFromView(msg: FromResultsViewMsg): Promise<void> {
-    switch (msg.t) {
-      case 'viewSourceFile': {
-        await jumpToLocation(msg, this.databaseManager, this.logger);
-        break;
-      }
-      case 'toggleDiagnostics': {
-        if (msg.visible) {
-          const databaseItem = this.databaseManager.findDatabaseItem(
-            Uri.parse(msg.databaseUri)
-          );
-          if (databaseItem !== undefined) {
-            await this.showResultsAsDiagnostics(
-              msg.origResultsPaths,
-              msg.metadata,
-              databaseItem
-            );
-          }
-        } else {
-          // TODO: Only clear diagnostics on the same database.
-          this._diagnosticCollection.clear();
-        }
-        break;
-      }
-      case 'resultViewLoaded':
-        this._panelLoaded = true;
-        this._panelLoadedCallBacks.forEach((cb) => cb());
-        this._panelLoadedCallBacks = [];
-        break;
-      case 'changeSort':
-        await this.changeRawSortState(msg.resultSetName, msg.sortState);
-        break;
-      case 'changeInterpretedSort':
-        await this.changeInterpretedSortState(msg.sortState);
-        break;
-      case 'changePage':
-        if (msg.selectedTable === ALERTS_TABLE_NAME) {
-          await this.showPageOfInterpretedResults(msg.pageNumber);
-        }
-        else {
-          await this.showPageOfRawResults(
-            msg.selectedTable,
-            msg.pageNumber,
-            // When we are in an unsorted state, we guarantee that
-            // sortedResultsInfo doesn't have an entry for the current
-            // result set. Use this to determine whether or not we use
-            // the sorted bqrs file.
-            this._displayedQuery?.sortedResultsInfo.has(msg.selectedTable) || false
-          );
-        }
-        break;
-      default:
-        assertNever(msg);
-    }
-  }
-
-  postMessage(msg: IntoResultsViewMsg): Thenable<boolean> {
-    return this.getPanel().webview.postMessage(msg);
-  }
-
-  private waitForPanelLoaded(): Promise<void> {
-    return new Promise((resolve) => {
-      if (this._panelLoaded) {
-        resolve();
-      } else {
-        this._panelLoadedCallBacks.push(resolve);
-      }
-    });
-  }
-
   /**
    * Show query results in webview panel.
-   * @param results Evaluation info for the executed query.
+   * @param fullQuery Evaluation info for the executed query.
    * @param shouldKeepOldResultsWhileRendering Should keep old results while rendering.
    * @param forceReveal Force the webview panel to be visible and
    * Appropriate when the user has just performed an explicit
@@ -315,58 +322,59 @@ export class InterfaceManager extends DisposableObject {
    * history entry.
    */
   public async showResults(
-    results: CompletedQuery,
+    fullQuery: CompletedLocalQueryInfo,
     forceReveal: WebviewReveal,
     shouldKeepOldResultsWhileRendering = false
   ): Promise<void> {
-    if (results.result.resultType !== messages.QueryResultType.SUCCESS) {
+    if (!fullQuery.completedQuery.successful) {
       return;
     }
 
     this._interpretation = undefined;
     const interpretationPage = await this.interpretResultsInfo(
-      results.query,
-      results.interpretedResultsSortState
+      fullQuery.completedQuery.query,
+      fullQuery.completedQuery.interpretedResultsSortState
     );
 
     const sortedResultsMap: SortedResultsMap = {};
-    results.sortedResultsInfo.forEach(
-      (v, k) =>
+    Object.entries(fullQuery.completedQuery.sortedResultsInfo).forEach(
+      ([k, v]) =>
         (sortedResultsMap[k] = this.convertPathPropertiesToWebviewUris(v))
     );
 
-    this._displayedQuery = results;
+    this._displayedQuery = fullQuery;
 
     const panel = this.getPanel();
     await this.waitForPanelLoaded();
-    if (forceReveal === WebviewReveal.Forced) {
-      panel.reveal(undefined, true);
-    } else if (!panel.visible) {
-      // The results panel exists, (`.getPanel()` guarantees it) but
-      // is not visible; it's in a not-currently-viewed tab. Show a
-      // more asynchronous message to not so abruptly interrupt
-      // user's workflow by immediately revealing the panel.
-      const showButton = 'View Results';
-      const queryName = results.queryName;
-      const resultPromise = vscode.window.showInformationMessage(
-        `Finished running query ${
-        queryName.length > 0 ? ` "${queryName}"` : ''
-        }.`,
-        showButton
-      );
-      // Address this click asynchronously so we still update the
-      // query history immediately.
-      resultPromise.then((result) => {
-        if (result === showButton) {
-          panel.reveal();
-        }
-      });
+    if (!panel.visible) {
+      if (forceReveal === WebviewReveal.Forced) {
+        panel.reveal(undefined, true);
+      } else {
+        // The results panel exists, (`.getPanel()` guarantees it) but
+        // is not visible; it's in a not-currently-viewed tab. Show a
+        // more asynchronous message to not so abruptly interrupt
+        // user's workflow by immediately revealing the panel.
+        const showButton = 'View Results';
+        const queryName = this.labelProvider.getShortLabel(fullQuery);
+        const resultPromise = vscode.window.showInformationMessage(
+          `Finished running query ${queryName.length > 0 ? ` "${queryName}"` : ''
+          }.`,
+          showButton
+        );
+        // Address this click asynchronously so we still update the
+        // query history immediately.
+        void resultPromise.then((result) => {
+          if (result === showButton) {
+            panel.reveal();
+          }
+        });
+      }
     }
 
     // Note that the resultSetSchemas will return offsets for the default (unsorted) page,
     // which may not be correct. However, in this case, it doesn't matter since we only
     // need the first offset, which will be the same no matter which sorting we use.
-    const resultSetSchemas = await this.getResultSetSchemas(results);
+    const resultSetSchemas = await this.getResultSetSchemas(fullQuery.completedQuery);
     const resultSetNames = resultSetSchemas.map(schema => schema.name);
 
     const selectedTable = getDefaultResultSetName(resultSetNames);
@@ -376,7 +384,7 @@ export class InterfaceManager extends DisposableObject {
 
     // Use sorted results path if it exists. This may happen if we are
     // reloading the results view after it has been sorted in the past.
-    const resultsPath = results.getResultsPath(selectedTable);
+    const resultsPath = fullQuery.completedQuery.getResultsPath(selectedTable);
     const pageSize = PAGE_SIZE.getValue<number>();
     const chunk = await this.cliServer.bqrsDecode(
       resultsPath,
@@ -391,10 +399,11 @@ export class InterfaceManager extends DisposableObject {
       }
     );
     const resultSet = transformBqrsResultSet(schema, chunk);
+    fullQuery.completedQuery.setResultCount(interpretationPage?.numTotalResults || resultSet.schema.rows);
     const parsedResultSets: ParsedResultSets = {
       pageNumber: 0,
       pageSize,
-      numPages: numPagesOfResultSet(resultSet),
+      numPages: numPagesOfResultSet(resultSet, this._interpretation),
       numInterpretedPages: numInterpretedPages(this._interpretation),
       resultSet: { ...resultSet, t: 'RawResultSet' },
       selectedTable: undefined,
@@ -404,15 +413,17 @@ export class InterfaceManager extends DisposableObject {
     await this.postMessage({
       t: 'setState',
       interpretation: interpretationPage,
-      origResultsPaths: results.query.resultsPaths,
+      origResultsPaths: fullQuery.completedQuery.query.resultsPaths,
       resultsPath: this.convertPathToWebviewUri(
-        results.query.resultsPaths.resultsPath
+        fullQuery.completedQuery.query.resultsPaths.resultsPath
       ),
       parsedResultSets,
       sortedResultsMap,
-      database: results.database,
+      database: fullQuery.initialInfo.databaseInfo,
       shouldKeepOldResultsWhileRendering,
-      metadata: results.query.metadata,
+      metadata: fullQuery.completedQuery.query.metadata,
+      queryName: this.labelProvider.getLabel(fullQuery),
+      queryPath: fullQuery.initialInfo.queryPath
     });
   }
 
@@ -428,27 +439,29 @@ export class InterfaceManager extends DisposableObject {
     if (this._interpretation === undefined) {
       throw new Error('Trying to show interpreted results but interpretation was undefined');
     }
-    if (this._interpretation.sarif.runs[0].results === undefined) {
+    if (this._interpretation.data.t === 'SarifInterpretationData' && this._interpretation.data.runs[0].results === undefined) {
       throw new Error('Trying to show interpreted results but results were undefined');
     }
 
-    const resultSetSchemas = await this.getResultSetSchemas(this._displayedQuery);
+    const resultSetSchemas = await this.getResultSetSchemas(this._displayedQuery.completedQuery);
     const resultSetNames = resultSetSchemas.map(schema => schema.name);
 
     await this.postMessage({
       t: 'showInterpretedPage',
       interpretation: this.getPageOfInterpretedResults(pageNumber),
-      database: this._displayedQuery.database,
-      metadata: this._displayedQuery.query.metadata,
+      database: this._displayedQuery.initialInfo.databaseInfo,
+      metadata: this._displayedQuery.completedQuery.query.metadata,
       pageNumber,
       resultSetNames,
-      pageSize: PAGE_SIZE.getValue(),
+      pageSize: interpretedPageSize(this._interpretation),
       numPages: numInterpretedPages(this._interpretation),
+      queryName: this.labelProvider.getLabel(this._displayedQuery),
+      queryPath: this._displayedQuery.initialInfo.queryPath
     });
   }
 
-  private async getResultSetSchemas(results: CompletedQuery, selectedTable = ''): Promise<ResultSetSchema[]> {
-    const resultsPath = results.getResultsPath(selectedTable);
+  private async getResultSetSchemas(completedQuery: CompletedQueryInfo, selectedTable = ''): Promise<ResultSetSchema[]> {
+    const resultsPath = completedQuery.getResultsPath(selectedTable);
     const schemas = await this.cliServer.bqrsInfo(
       resultsPath,
       PAGE_SIZE.getValue()
@@ -456,6 +469,11 @@ export class InterfaceManager extends DisposableObject {
     return schemas['result-sets'];
   }
 
+  public async openFile(filePath: string) {
+    const textDocument = await vscode.workspace.openTextDocument(filePath);
+    await vscode.window.showTextDocument(textDocument, vscode.ViewColumn.One);
+  }
+
   /**
    * Show a page of raw results from the chosen table.
    */
@@ -470,13 +488,18 @@ export class InterfaceManager extends DisposableObject {
     }
 
     const sortedResultsMap: SortedResultsMap = {};
-    results.sortedResultsInfo.forEach(
-      (v, k) =>
+    Object.entries(results.completedQuery.sortedResultsInfo).forEach(
+      ([k, v]) =>
         (sortedResultsMap[k] = this.convertPathPropertiesToWebviewUris(v))
     );
 
-    const resultSetSchemas = await this.getResultSetSchemas(results, sorted ? selectedTable : '');
-    const resultSetNames = resultSetSchemas.map(schema => schema.name);
+    const resultSetSchemas = await this.getResultSetSchemas(results.completedQuery, sorted ? selectedTable : '');
+
+    // If there is a specific sorted table selected, a different bqrs file is loaded that doesn't have all the result set names.
+    // Make sure that we load all result set names here.
+    // See https://github.com/github/vscode-codeql/issues/1005
+    const allResultSetSchemas = sorted ? await this.getResultSetSchemas(results.completedQuery, '') : resultSetSchemas;
+    const resultSetNames = allResultSetSchemas.map(schema => schema.name);
 
     const schema = resultSetSchemas.find(
       (resultSet) => resultSet.name == selectedTable
@@ -486,7 +509,7 @@ export class InterfaceManager extends DisposableObject {
 
     const pageSize = PAGE_SIZE.getValue<number>();
     const chunk = await this.cliServer.bqrsDecode(
-      results.getResultsPath(selectedTable, sorted),
+      results.completedQuery.getResultsPath(selectedTable, sorted),
       schema.name,
       {
         offset: schema.pagination?.offsets[pageNumber],
@@ -508,15 +531,17 @@ export class InterfaceManager extends DisposableObject {
     await this.postMessage({
       t: 'setState',
       interpretation: this._interpretation,
-      origResultsPaths: results.query.resultsPaths,
+      origResultsPaths: results.completedQuery.query.resultsPaths,
       resultsPath: this.convertPathToWebviewUri(
-        results.query.resultsPaths.resultsPath
+        results.completedQuery.query.resultsPaths.resultsPath
       ),
       parsedResultSets,
       sortedResultsMap,
-      database: results.database,
+      database: results.initialInfo.databaseInfo,
       shouldKeepOldResultsWhileRendering: false,
-      metadata: results.query.metadata,
+      metadata: results.completedQuery.query.metadata,
+      queryName: this.labelProvider.getLabel(results),
+      queryPath: results.initialInfo.queryPath
     });
   }
 
@@ -526,30 +551,50 @@ export class InterfaceManager extends DisposableObject {
     sourceInfo: cli.SourceInfo | undefined,
     sourceLocationPrefix: string,
     sortState: InterpretedResultsSortState | undefined
-  ): Promise<Interpretation> {
-    const sarif = await interpretResults(
-      this.cliServer,
-      metadata,
-      resultsPaths,
-      sourceInfo
-    );
-    sarif.runs.forEach(run => {
-      if (run.results !== undefined)
-        sortInterpretedResults(run.results, sortState);
-    });
+  ): Promise<Interpretation | undefined> {
+    if (!resultsPaths) {
+      void this.logger.log('No results path. Cannot display interpreted results.');
+      return undefined;
+    }
+    let data;
+    let numTotalResults;
+    if (metadata?.kind === GRAPH_TABLE_NAME) {
+      data = await interpretGraphResults(
+        this.cliServer,
+        metadata,
+        resultsPaths,
+        sourceInfo
+      );
+      numTotalResults = data.dot.length;
+    } else {
+      const sarif = await interpretResultsSarif(
+        this.cliServer,
+        metadata,
+        resultsPaths,
+        sourceInfo
+      );
 
-    const numTotalResults = (() => {
-      if (sarif.runs.length === 0) return 0;
-      if (sarif.runs[0].results === undefined) return 0;
-      return sarif.runs[0].results.length;
-    })();
+      sarif.runs.forEach(run => {
+        if (run.results) {
+          sortInterpretedResults(run.results, sortState);
+        }
+      });
+
+      sarif.sortState = sortState;
+      data = sarif;
+
+      numTotalResults = (() => {
+        return sarif.runs?.[0]?.results
+          ? sarif.runs[0].results.length
+          : 0;
+      })();
+    }
 
     const interpretation: Interpretation = {
-      sarif,
+      data,
       sourceLocationPrefix,
       numTruncatedResults: 0,
-      numTotalResults,
-      sortState,
+      numTotalResults
     };
     this._interpretation = interpretation;
     return interpretation;
@@ -558,7 +603,6 @@ export class InterfaceManager extends DisposableObject {
   private getPageOfInterpretedResults(
     pageNumber: number
   ): Interpretation {
-
     function getPageOfRun(run: Sarif.Run): Sarif.Run {
       return {
         ...run, results: run.results?.slice(
@@ -568,32 +612,44 @@ export class InterfaceManager extends DisposableObject {
       };
     }
 
-    if (this._interpretation === undefined) {
+    const interp = this._interpretation;
+    if (interp === undefined) {
       throw new Error('Tried to get interpreted results before interpretation finished');
     }
-    if (this._interpretation.sarif.runs.length !== 1) {
-      this.logger.log(`Warning: SARIF file had ${this._interpretation.sarif.runs.length} runs, expected 1`);
+
+    if (interp.data.t !== 'SarifInterpretationData')
+      return interp;
+
+    if (interp.data.runs.length !== 1) {
+      void this.logger.log(`Warning: SARIF file had ${interp.data.runs.length} runs, expected 1`);
     }
-    const interp = this._interpretation;
+
     return {
       ...interp,
-      sarif: { ...interp.sarif, runs: [getPageOfRun(interp.sarif.runs[0])] },
+      data: {
+        ...interp.data,
+        runs: [getPageOfRun(interp.data.runs[0])]
+      }
     };
   }
 
   private async interpretResultsInfo(
-    query: QueryInfo,
+    query: QueryEvaluationInfo,
     sortState: InterpretedResultsSortState | undefined
   ): Promise<Interpretation | undefined> {
     if (
-      (await query.canHaveInterpretedResults()) &&
+      query.canHaveInterpretedResults() &&
       query.quickEvalPosition === undefined // never do results interpretation if quickEval
     ) {
       try {
-        const sourceLocationPrefix = await query.dbItem.getSourceLocationPrefix(
+        const dbItem = this.databaseManager.findDatabaseItem(Uri.file(query.dbItemPath));
+        if (!dbItem) {
+          throw new Error(`Could not find database item for ${query.dbItemPath}`);
+        }
+        const sourceLocationPrefix = await dbItem.getSourceLocationPrefix(
           this.cliServer
         );
-        const sourceArchiveUri = query.dbItem.sourceArchive;
+        const sourceArchiveUri = dbItem.sourceArchive;
         const sourceInfo =
           sourceArchiveUri === undefined
             ? undefined
@@ -611,8 +667,8 @@ export class InterfaceManager extends DisposableObject {
       } catch (e) {
         // If interpretation fails, accept the error and continue
         // trying to render uninterpreted results anyway.
-        this.logger.log(
-          `Exception during results interpretation: ${e.message}. Will show raw results instead.`
+        void showAndLogErrorMessage(
+          `Showing raw results instead of interpreted ones due to an error. ${getErrorMessage(e)}`
         );
       }
     }
@@ -644,12 +700,15 @@ export class InterfaceManager extends DisposableObject {
       undefined
     );
 
+    if (!interpretation) {
+      return;
+    }
+
     try {
       await this.showProblemResultsAsDiagnostics(interpretation, database);
     } catch (e) {
-      const msg = e instanceof Error ? e.message : e.toString();
-      this.logger.log(
-        `Exception while computing problem results as diagnostics: ${msg}`
+      void this.logger.log(
+        `Exception while computing problem results as diagnostics: ${getErrorMessage(e)}`
       );
       this._diagnosticCollection.clear();
     }
@@ -659,10 +718,13 @@ export class InterfaceManager extends DisposableObject {
     interpretation: Interpretation,
     databaseItem: DatabaseItem
   ): Promise<void> {
-    const { sarif, sourceLocationPrefix } = interpretation;
+    const { data, sourceLocationPrefix } = interpretation;
 
-    if (!sarif.runs || !sarif.runs[0].results) {
-      this.logger.log(
+    if (data.t !== 'SarifInterpretationData')
+      return;
+
+    if (!data.runs || !data.runs[0].results) {
+      void this.logger.log(
         'Didn\'t find a run in the sarif results. Error processing sarif?'
       );
       return;
@@ -670,14 +732,14 @@ export class InterfaceManager extends DisposableObject {
 
     const diagnostics: [Uri, ReadonlyArray<Diagnostic>][] = [];
 
-    for (const result of sarif.runs[0].results) {
+    for (const result of data.runs[0].results) {
       const message = result.message.text;
       if (message === undefined) {
-        this.logger.log('Sarif had result without plaintext message');
+        void this.logger.log('Sarif had result without plaintext message');
         continue;
       }
       if (!result.locations) {
-        this.logger.log('Sarif had result without location');
+        void this.logger.log('Sarif had result without location');
         continue;
       }
 
@@ -690,7 +752,7 @@ export class InterfaceManager extends DisposableObject {
       }
       const resultLocation = tryResolveLocation(sarifLoc, databaseItem);
       if (!resultLocation) {
-        this.logger.log('Sarif location was not resolvable ' + sarifLoc);
+        void this.logger.log('Sarif location was not resolvable ' + sarifLoc);
         continue;
       }
       const parsedMessage = parseSarifPlainTextMessage(message);

extensions/ql-vscode/src/json-rpc-server.ts

@@ -0,0 +1,30 @@
+import { Logger } from './logging';
+import * as cp from 'child_process';
+import { Disposable } from 'vscode';
+import { MessageConnection } from 'vscode-jsonrpc';
+
+
+/** A running query server process and its associated message connection. */
+export class ServerProcess implements Disposable {
+  child: cp.ChildProcess;
+  connection: MessageConnection;
+  logger: Logger;
+
+  constructor(child: cp.ChildProcess, connection: MessageConnection, private name: string, logger: Logger) {
+    this.child = child;
+    this.connection = connection;
+    this.logger = logger;
+  }
+
+  dispose(): void {
+    void this.logger.log(`Stopping ${this.name}...`);
+    this.connection.dispose();
+    this.child.stdin!.end();
+    this.child.stderr!.destroy();
+    // TODO kill the process if it doesn't terminate after a certain time limit.
+
+    // On Windows, we usually have to terminate the process before closing its stdout.
+    this.child.stdout!.destroy();
+    void this.logger.log(`Stopped ${this.name}.`);
+  }
+}

extensions/ql-vscode/src/legacy-query-server/legacyRunner.ts

@@ -0,0 +1,65 @@
+import { CancellationToken } from 'vscode';
+import { ProgressCallback } from '../commandRunner';
+import { DatabaseItem } from '../databases';
+import { Dataset, deregisterDatabases, registerDatabases } from '../pure/legacy-messages';
+import { InitialQueryInfo, LocalQueryInfo } from '../query-results';
+import { QueryRunner } from '../queryRunner';
+import { QueryWithResults } from '../run-queries-shared';
+import { QueryServerClient } from './queryserver-client';
+import { clearCacheInDatabase, compileAndRunQueryAgainstDatabase } from './run-queries';
+import { upgradeDatabaseExplicit } from './upgrades';
+
+export class LegacyQueryRunner extends QueryRunner {
+
+
+  constructor(public readonly qs: QueryServerClient) {
+    super();
+  }
+
+  get cliServer() {
+    return this.qs.cliServer;
+  }
+
+  async restartQueryServer(progress: ProgressCallback, token: CancellationToken): Promise<void> {
+    await this.qs.restartQueryServer(progress, token);
+  }
+
+  onStart(callBack: (progress: ProgressCallback, token: CancellationToken) => Promise<void>) {
+    this.qs.onDidStartQueryServer(callBack);
+  }
+  async clearCacheInDatabase(dbItem: DatabaseItem, progress: ProgressCallback, token: CancellationToken): Promise<void> {
+    await clearCacheInDatabase(this.qs, dbItem, progress, token);
+  }
+  async compileAndRunQueryAgainstDatabase(dbItem: DatabaseItem, initialInfo: InitialQueryInfo, queryStorageDir: string, progress: ProgressCallback, token: CancellationToken, templates?: Record<string, string>, queryInfo?: LocalQueryInfo): Promise<QueryWithResults> {
+    return await compileAndRunQueryAgainstDatabase(this.qs.cliServer, this.qs, dbItem, initialInfo, queryStorageDir, progress, token, templates, queryInfo);
+  }
+
+  async deregisterDatabase(progress: ProgressCallback, token: CancellationToken, dbItem: DatabaseItem): Promise<void> {
+    if (dbItem.contents && (await this.qs.cliServer.cliConstraints.supportsDatabaseRegistration())) {
+      const databases: Dataset[] = [{
+        dbDir: dbItem.contents.datasetUri.fsPath,
+        workingSet: 'default'
+      }];
+      await this.qs.sendRequest(deregisterDatabases, { databases }, token, progress);
+    }
+  }
+  async registerDatabase(progress: ProgressCallback, token: CancellationToken, dbItem: DatabaseItem): Promise<void> {
+    if (dbItem.contents && (await this.qs.cliServer.cliConstraints.supportsDatabaseRegistration())) {
+      const databases: Dataset[] = [{
+        dbDir: dbItem.contents.datasetUri.fsPath,
+        workingSet: 'default'
+      }];
+      await this.qs.sendRequest(registerDatabases, { databases }, token, progress);
+    }
+  }
+
+  async upgradeDatabaseExplicit(dbItem: DatabaseItem, progress: ProgressCallback, token: CancellationToken): Promise<void> {
+    await upgradeDatabaseExplicit(this.qs, dbItem, progress, token);
+  }
+
+  async clearPackCache(): Promise<void> {
+    /**
+     * Nothing needs to be done
+     */
+  }
+}

extensions/ql-vscode/src/legacy-query-server/queryserver-client.ts

@@ -1,45 +1,25 @@
-import * as cp from 'child_process';
 import * as path from 'path';
-import { DisposableObject } from './vscode-utils/disposable-object';
-import { Disposable } from 'vscode';
-import { CancellationToken, createMessageConnection, MessageConnection, RequestType } from 'vscode-jsonrpc';
-import * as cli from './cli';
-import { QueryServerConfig } from './config';
-import { Logger, ProgressReporter } from './logging';
-import { completeQuery, EvaluationResult, progress, ProgressMessage, WithProgressId } from './pure/messages';
-import * as messages from './pure/messages';
+import * as fs from 'fs-extra';
+
+import { DisposableObject } from '../pure/disposable-object';
+import { CancellationToken, commands } from 'vscode';
+import { createMessageConnection, RequestType } from 'vscode-jsonrpc';
+import * as cli from '../cli';
+import { QueryServerConfig } from '../config';
+import { Logger, ProgressReporter } from '../logging';
+import { completeQuery, EvaluationResult, progress, ProgressMessage, WithProgressId } from '../pure/legacy-messages';
+import * as messages from '../pure/legacy-messages';
+import { ProgressCallback, ProgressTask } from '../commandRunner';
+import { findQueryLogFile } from '../run-queries-shared';
+import { ServerProcess } from '../json-rpc-server';
+
+type WithProgressReporting = (task: (progress: ProgressReporter, token: CancellationToken) => Thenable<void>) => Thenable<void>;
 
 type ServerOpts = {
   logger: Logger;
+  contextStoragePath: string;
 }
 
-/** A running query server process and its associated message connection. */
-class ServerProcess implements Disposable {
-  child: cp.ChildProcess;
-  connection: MessageConnection;
-  logger: Logger;
-
-  constructor(child: cp.ChildProcess, connection: MessageConnection, logger: Logger) {
-    this.child = child;
-    this.connection = connection;
-    this.logger = logger;
-  }
-
-  dispose(): void {
-    this.logger.log('Stopping query server...');
-    this.connection.dispose();
-    this.child.stdin!.end();
-    this.child.stderr!.destroy();
-    // TODO kill the process if it doesn't terminate after a certain time limit.
-
-    // On Windows, we usually have to terminate the process before closing its stdout.
-    this.child.stdout!.destroy();
-    this.logger.log('Stopped query server.');
-  }
-}
-
-type WithProgressReporting = (task: (progress: ProgressReporter, token: CancellationToken) => Thenable<void>) => Thenable<void>;
-
 /**
  * Client that manages a query server process.
  * The server process is started upon initialization and tracked during its lifetime.
@@ -47,22 +27,36 @@ type WithProgressReporting = (task: (progress: ProgressReporter, token: Cancella
  * to restart it (which disposes the existing process and starts a new one).
  */
 export class QueryServerClient extends DisposableObject {
+
   serverProcess?: ServerProcess;
   evaluationResultCallbacks: { [key: number]: (res: EvaluationResult) => void };
   progressCallbacks: { [key: number]: ((res: ProgressMessage) => void) | undefined };
   nextCallback: number;
   nextProgress: number;
   withProgressReporting: WithProgressReporting;
-  public activeQueryName: string | undefined;
 
-  constructor(readonly config: QueryServerConfig, readonly cliServer: cli.CodeQLCliServer, readonly opts: ServerOpts, withProgressReporting: WithProgressReporting) {
+  private readonly queryServerStartListeners = [] as ProgressTask<void>[];
+
+  // Can't use standard vscode EventEmitter here since they do not cause the calling
+  // function to fail if one of the event handlers fail. This is something that
+  // we need here.
+  readonly onDidStartQueryServer = (e: ProgressTask<void>) => {
+    this.queryServerStartListeners.push(e);
+  }
+
+  public activeQueryLogFile: string | undefined;
+
+  constructor(
+    readonly config: QueryServerConfig,
+    readonly cliServer: cli.CodeQLCliServer,
+    readonly opts: ServerOpts,
+    withProgressReporting: WithProgressReporting
+  ) {
     super();
     // When the query server configuration changes, restart the query server.
     if (config.onDidChangeConfiguration !== undefined) {
-      this.push(config.onDidChangeConfiguration(async () => {
-        this.logger.log('Restarting query server due to configuration changes...');
-        await this.restartQueryServer();
-      }, this));
+      this.push(config.onDidChangeConfiguration(() =>
+        commands.executeCommand('codeQL.restartQueryServer')));
     }
     this.withProgressReporting = withProgressReporting;
     this.nextCallback = 0;
@@ -80,14 +74,24 @@ export class QueryServerClient extends DisposableObject {
     if (this.serverProcess !== undefined) {
       this.disposeAndStopTracking(this.serverProcess);
     } else {
-      this.logger.log('No server process to be stopped.');
+      void this.logger.log('No server process to be stopped.');
     }
   }
 
   /** Restarts the query server by disposing of the current server process and then starting a new one. */
-  async restartQueryServer(): Promise<void> {
+  async restartQueryServer(
+    progress: ProgressCallback,
+    token: CancellationToken
+  ): Promise<void> {
     this.stopQueryServer();
     await this.startQueryServer();
+
+    // Ensure we await all responses from event handlers so that
+    // errors can be properly reported to the user.
+    await Promise.all(this.queryServerStartListeners.map(handler => handler(
+      progress,
+      token
+    )));
   }
 
   showLog(): void {
@@ -104,12 +108,43 @@ export class QueryServerClient extends DisposableObject {
   private async startQueryServerImpl(progressReporter: ProgressReporter): Promise<void> {
     const ramArgs = await this.cliServer.resolveRam(this.config.queryMemoryMb, progressReporter);
     const args = ['--threads', this.config.numThreads.toString()].concat(ramArgs);
+
+    if (this.config.saveCache) {
+      args.push('--save-cache');
+    }
+
+    if (this.config.cacheSize > 0) {
+      args.push('--max-disk-cache');
+      args.push(this.config.cacheSize.toString());
+    }
+
+    if (await this.cliServer.cliConstraints.supportsDatabaseRegistration()) {
+      args.push('--require-db-registration');
+    }
+
+    if (await this.cliServer.cliConstraints.supportsOldEvalStats() && !(await this.cliServer.cliConstraints.supportsPerQueryEvalLog())) {
+      args.push('--old-eval-stats');
+    }
+
+    if (await this.cliServer.cliConstraints.supportsStructuredEvalLog()) {
+      const structuredLogFile = `${this.opts.contextStoragePath}/structured-evaluator-log.json`;
+      await fs.ensureFile(structuredLogFile);
+
+      args.push('--evaluator-log');
+      args.push(structuredLogFile);
+
+      // We hard-code the verbosity level to 5 and minify to false.
+      // This will be the behavior of the per-query structured logging in the CLI after 2.8.3.
+      args.push('--evaluator-log-level');
+      args.push('5');
+    }
+
     if (this.config.debug) {
       args.push('--debug', '--tuple-counting');
     }
 
     if (cli.shouldDebugQueryServer()) {
-      args.push('-J=-agentlib:jdwp=transport=dt_socket,address=localhost:9010,server=y,suspend=n,quiet=y');
+      args.push('-J=-agentlib:jdwp=transport=dt_socket,address=localhost:9010,server=n,suspend=y,quiet=y');
     }
 
     const child = cli.spawnServer(
@@ -120,7 +155,7 @@ export class QueryServerClient extends DisposableObject {
       this.logger,
       data => this.logger.log(data.toString(), {
         trailingNewline: false,
-        additionalLogLocation: this.activeQueryName
+        additionalLogLocation: this.activeQueryLogFile
       }),
       undefined, // no listener for stdout
       progressReporter
@@ -129,13 +164,8 @@ export class QueryServerClient extends DisposableObject {
     const connection = createMessageConnection(child.stdout, child.stdin);
     connection.onRequest(completeQuery, res => {
       if (!(res.runId in this.evaluationResultCallbacks)) {
-        this.logger.log(`No callback associated with run id ${res.runId}, continuing without executing any callback`);
-      }
-      else {
-        const baseLocation = this.logger.getBaseLocation();
-        if (baseLocation && this.activeQueryName) {
-          res.logFileLocation = path.join(baseLocation, this.activeQueryName);
-        }
+        void this.logger.log(`No callback associated with run id ${res.runId}, continuing without executing any callback`);
+      } else {
         this.evaluationResultCallbacks[res.runId](res);
       }
       return {};
@@ -146,7 +176,7 @@ export class QueryServerClient extends DisposableObject {
         callback(res);
       }
     });
-    this.serverProcess = new ServerProcess(child, connection, this.opts.logger);
+    this.serverProcess = new ServerProcess(child, connection, 'Query server', this.logger);
     // Ensure the server process is disposed together with this client.
     this.track(this.serverProcess);
     connection.listen();
@@ -168,7 +198,7 @@ export class QueryServerClient extends DisposableObject {
   }
 
   get serverProcessPid(): number {
-    return this.serverProcess!.child.pid;
+    return this.serverProcess!.child.pid || 0;
   }
 
   async sendRequest<P, R, E, RO>(type: RequestType<WithProgressId<P>, R, E, RO>, parameter: P, token?: CancellationToken, progress?: (res: ProgressMessage) => void): Promise<R> {
@@ -196,8 +226,7 @@ export class QueryServerClient extends DisposableObject {
    */
   private updateActiveQuery(method: string, parameter: any): void {
     if (method === messages.compileQuery.method) {
-      const queryPath = parameter?.queryToCheck?.queryPath || 'unknown';
-      this.activeQueryName = `query-${path.basename(queryPath)}-${this.nextProgress}.log`;
+      this.activeQueryLogFile = findQueryLogFile(path.dirname(parameter.resultPath));
     }
   }
 }

extensions/ql-vscode/src/legacy-query-server/run-queries.ts

@@ -0,0 +1,526 @@
+import * as crypto from 'crypto';
+import * as fs from 'fs-extra';
+import * as tmp from 'tmp-promise';
+import * as path from 'path';
+import {
+  CancellationToken,
+  Uri,
+} from 'vscode';
+import { ErrorCodes, ResponseError } from 'vscode-languageclient';
+
+import * as cli from '../cli';
+import { DatabaseItem, } from '../databases';
+import {
+  getOnDiskWorkspaceFolders,
+  showAndLogErrorMessage,
+  showAndLogWarningMessage,
+  tryGetQueryMetadata,
+  upgradesTmpDir
+} from '../helpers';
+import { ProgressCallback } from '../commandRunner';
+import { QueryMetadata } from '../pure/interface-types';
+import { logger } from '../logging';
+import * as messages from '../pure/legacy-messages';
+import { InitialQueryInfo, LocalQueryInfo } from '../query-results';
+import * as qsClient from './queryserver-client';
+import { getErrorMessage } from '../pure/helpers-pure';
+import { compileDatabaseUpgradeSequence, upgradeDatabaseExplicit } from './upgrades';
+import { QueryEvaluationInfo, QueryWithResults } from '../run-queries-shared';
+
+/**
+ * A collection of evaluation-time information about a query,
+ * including the query itself, and where we have decided to put
+ * temporary files associated with it, such as the compiled query
+ * output and results.
+ */
+export class QueryInProgress {
+
+  public queryEvalInfo: QueryEvaluationInfo;
+  /**
+   * Note that in the {@link slurpQueryHistory} method, we create a QueryEvaluationInfo instance
+   * by explicitly setting the prototype in order to avoid calling this constructor.
+   */
+  constructor(
+    readonly querySaveDir: string,
+    readonly dbItemPath: string,
+    databaseHasMetadataFile: boolean,
+    readonly queryDbscheme: string, // the dbscheme file the query expects, based on library path resolution
+    readonly quickEvalPosition?: messages.Position,
+    readonly metadata?: QueryMetadata,
+    readonly templates?: Record<string, string>,
+  ) {
+    this.queryEvalInfo = new QueryEvaluationInfo(querySaveDir, dbItemPath, databaseHasMetadataFile, quickEvalPosition, metadata);
+    /**/
+  }
+
+  get compiledQueryPath() {
+    return path.join(this.querySaveDir, 'compiledQuery.qlo');
+  }
+
+
+  async run(
+    qs: qsClient.QueryServerClient,
+    upgradeQlo: string | undefined,
+    availableMlModels: cli.MlModelInfo[],
+    dbItem: DatabaseItem,
+    progress: ProgressCallback,
+    token: CancellationToken,
+    queryInfo?: LocalQueryInfo,
+  ): Promise<messages.EvaluationResult> {
+    if (!dbItem.contents || dbItem.error) {
+      throw new Error('Can\'t run query on invalid database.');
+    }
+
+    let result: messages.EvaluationResult | null = null;
+
+    const callbackId = qs.registerCallback(res => {
+      result = {
+        ...res,
+        logFileLocation: this.queryEvalInfo.logPath
+      };
+    });
+
+    const availableMlModelUris: messages.MlModel[] = availableMlModels.map(model => ({ uri: Uri.file(model.path).toString(true) }));
+
+    const queryToRun: messages.QueryToRun = {
+      resultsPath: this.queryEvalInfo.resultsPaths.resultsPath,
+      qlo: Uri.file(this.compiledQueryPath).toString(),
+      compiledUpgrade: upgradeQlo && Uri.file(upgradeQlo).toString(),
+      allowUnknownTemplates: true,
+      templateValues: createSimpleTemplates(this.templates),
+      availableMlModels: availableMlModelUris,
+      id: callbackId,
+      timeoutSecs: qs.config.timeoutSecs,
+    };
+
+    const dataset: messages.Dataset = {
+      dbDir: dbItem.contents.datasetUri.fsPath,
+      workingSet: 'default'
+    };
+    if (queryInfo && await qs.cliServer.cliConstraints.supportsPerQueryEvalLog()) {
+      await qs.sendRequest(messages.startLog, {
+        db: dataset,
+        logPath: this.queryEvalInfo.evalLogPath,
+      });
+
+    }
+    const params: messages.EvaluateQueriesParams = {
+      db: dataset,
+      evaluateId: callbackId,
+      queries: [queryToRun],
+      stopOnError: false,
+      useSequenceHint: false
+    };
+    try {
+      await qs.sendRequest(messages.runQueries, params, token, progress);
+      if (qs.config.customLogDirectory) {
+        void showAndLogWarningMessage(
+          `Custom log directories are no longer supported. The "codeQL.runningQueries.customLogDirectory" setting is deprecated. Unset the setting to stop seeing this message. Query logs saved to ${this.queryEvalInfo.logPath}.`
+        );
+      }
+    } finally {
+      qs.unRegisterCallback(callbackId);
+      if (queryInfo && await qs.cliServer.cliConstraints.supportsPerQueryEvalLog()) {
+        await qs.sendRequest(messages.endLog, {
+          db: dataset,
+          logPath: this.queryEvalInfo.evalLogPath,
+        });
+        if (await this.queryEvalInfo.hasEvalLog()) {
+          await this.queryEvalInfo.addQueryLogs(queryInfo, qs.cliServer, qs.logger);
+        } else {
+          void showAndLogWarningMessage(`Failed to write structured evaluator log to ${this.queryEvalInfo.evalLogPath}.`);
+        }
+      }
+    }
+    return result || {
+      evaluationTime: 0,
+      message: 'No result from server',
+      queryId: -1,
+      runId: callbackId,
+      resultType: messages.QueryResultType.OTHER_ERROR
+    };
+  }
+
+  async compile(
+    qs: qsClient.QueryServerClient,
+    program: messages.QlProgram,
+    progress: ProgressCallback,
+    token: CancellationToken,
+  ): Promise<messages.CompilationMessage[]> {
+    let compiled: messages.CheckQueryResult | undefined;
+    try {
+      const target = this.quickEvalPosition ? {
+        quickEval: { quickEvalPos: this.quickEvalPosition }
+      } : { query: {} };
+      const params: messages.CompileQueryParams = {
+        compilationOptions: {
+          computeNoLocationUrls: true,
+          failOnWarnings: false,
+          fastCompilation: false,
+          includeDilInQlo: true,
+          localChecking: false,
+          noComputeGetUrl: false,
+          noComputeToString: false,
+          computeDefaultStrings: true,
+          emitDebugInfo: true
+        },
+        extraOptions: {
+          timeoutSecs: qs.config.timeoutSecs
+        },
+        queryToCheck: program,
+        resultPath: this.compiledQueryPath,
+        target,
+      };
+
+      compiled = await qs.sendRequest(messages.compileQuery, params, token, progress);
+    } finally {
+      void qs.logger.log(' - - - COMPILATION DONE - - - ', { additionalLogLocation: this.queryEvalInfo.logPath });
+    }
+    return (compiled?.messages || []).filter(msg => msg.severity === messages.Severity.ERROR);
+  }
+}
+
+export async function clearCacheInDatabase(
+  qs: qsClient.QueryServerClient,
+  dbItem: DatabaseItem,
+  progress: ProgressCallback,
+  token: CancellationToken,
+): Promise<messages.ClearCacheResult> {
+  if (dbItem.contents === undefined) {
+    throw new Error('Can\'t clear the cache in an invalid database.');
+  }
+
+  const db: messages.Dataset = {
+    dbDir: dbItem.contents.datasetUri.fsPath,
+    workingSet: 'default',
+  };
+
+  const params: messages.ClearCacheParams = {
+    dryRun: false,
+    db,
+  };
+
+  return qs.sendRequest(messages.clearCache, params, token, progress);
+}
+
+
+/**
+ * Compare the dbscheme implied by the query `query` and that of the current database.
+ * - If they are compatible, do nothing.
+ * - If they are incompatible but the database can be upgraded, suggest that upgrade.
+ * - If they are incompatible and the database cannot be upgraded, throw an error.
+ */
+async function checkDbschemeCompatibility(
+  cliServer: cli.CodeQLCliServer,
+  qs: qsClient.QueryServerClient,
+  query: QueryInProgress,
+  qlProgram: messages.QlProgram,
+  dbItem: DatabaseItem,
+  progress: ProgressCallback,
+  token: CancellationToken,
+): Promise<void> {
+  const searchPath = getOnDiskWorkspaceFolders();
+
+  if (dbItem.contents?.dbSchemeUri !== undefined) {
+    const { finalDbscheme } = await cliServer.resolveUpgrades(dbItem.contents.dbSchemeUri.fsPath, searchPath, false);
+    const hash = async function(filename: string): Promise<string> {
+      return crypto.createHash('sha256').update(await fs.readFile(filename)).digest('hex');
+    };
+
+    // At this point, we have learned about three dbschemes:
+
+    // the dbscheme of the actual database we're querying.
+    const dbschemeOfDb = await hash(dbItem.contents.dbSchemeUri.fsPath);
+
+    // the dbscheme of the query we're running, including the library we've resolved it to use.
+    const dbschemeOfLib = await hash(query.queryDbscheme);
+
+    // the database we're able to upgrade to
+    const upgradableTo = await hash(finalDbscheme);
+
+    if (upgradableTo != dbschemeOfLib) {
+      reportNoUpgradePath(qlProgram, query);
+    }
+
+    if (upgradableTo == dbschemeOfLib &&
+      dbschemeOfDb != dbschemeOfLib) {
+      // Try to upgrade the database
+      await upgradeDatabaseExplicit(
+        qs,
+        dbItem,
+        progress,
+        token
+      );
+    }
+  }
+}
+
+function reportNoUpgradePath(qlProgram: messages.QlProgram, query: QueryInProgress): void {
+  throw new Error(
+    `Query ${qlProgram.queryPath} expects database scheme ${query.queryDbscheme}, but the current database has a different scheme, and no database upgrades are available. The current database scheme may be newer than the CodeQL query libraries in your workspace.\n\nPlease try using a newer version of the query libraries.`
+  );
+}
+
+/**
+ * Compile a non-destructive upgrade.
+ */
+async function compileNonDestructiveUpgrade(
+  qs: qsClient.QueryServerClient,
+  upgradeTemp: tmp.DirectoryResult,
+  query: QueryInProgress,
+  qlProgram: messages.QlProgram,
+  dbItem: DatabaseItem,
+  progress: ProgressCallback,
+  token: CancellationToken,
+): Promise<string> {
+
+  if (!dbItem?.contents?.dbSchemeUri) {
+    throw new Error('Database is invalid, and cannot be upgraded.');
+  }
+
+  // When packaging is used, dependencies may exist outside of the workspace and they are always on the resolved search path.
+  // When packaging is not used, all dependencies are in the workspace.
+  const upgradesPath = (await qs.cliServer.cliConstraints.supportsPackaging())
+    ? qlProgram.libraryPath
+    : getOnDiskWorkspaceFolders();
+
+  const { scripts, matchesTarget } = await qs.cliServer.resolveUpgrades(
+    dbItem.contents.dbSchemeUri.fsPath,
+    upgradesPath,
+    true,
+    query.queryDbscheme
+  );
+
+  if (!matchesTarget) {
+    reportNoUpgradePath(qlProgram, query);
+  }
+  const result = await compileDatabaseUpgradeSequence(qs, dbItem, scripts, upgradeTemp, progress, token);
+  if (result.compiledUpgrade === undefined) {
+    const error = result.error || '[no error message available]';
+    throw new Error(error);
+  }
+  // We can upgrade to the actual target
+  qlProgram.dbschemePath = query.queryDbscheme;
+  // We are new enough that we will always support single file upgrades.
+  return result.compiledUpgrade;
+}
+
+
+
+export async function compileAndRunQueryAgainstDatabase(
+  cliServer: cli.CodeQLCliServer,
+  qs: qsClient.QueryServerClient,
+  dbItem: DatabaseItem,
+  initialInfo: InitialQueryInfo,
+  queryStorageDir: string,
+  progress: ProgressCallback,
+  token: CancellationToken,
+  templates?: Record<string, string>,
+  queryInfo?: LocalQueryInfo, // May be omitted for queries not initiated by the user. If omitted we won't create a structured log for the query.
+): Promise<QueryWithResults> {
+  if (!dbItem.contents || !dbItem.contents.dbSchemeUri) {
+    throw new Error(`Database ${dbItem.databaseUri} does not have a CodeQL database scheme.`);
+  }
+
+  // Get the workspace folder paths.
+  const diskWorkspaceFolders = getOnDiskWorkspaceFolders();
+  // Figure out the library path for the query.
+  const packConfig = await cliServer.resolveLibraryPath(diskWorkspaceFolders, initialInfo.queryPath);
+
+  if (!packConfig.dbscheme) {
+    throw new Error('Could not find a database scheme for this query. Please check that you have a valid qlpack.yml file for this query, which refers to a database scheme either in the `dbscheme` field or through one of its dependencies.');
+  }
+
+  // Check whether the query has an entirely different schema from the
+  // database. (Queries that merely need the database to be upgraded
+  // won't trigger this check)
+  // This test will produce confusing results if we ever change the name of the database schema files.
+  const querySchemaName = path.basename(packConfig.dbscheme);
+  const dbSchemaName = path.basename(dbItem.contents.dbSchemeUri.fsPath);
+  if (querySchemaName != dbSchemaName) {
+    void logger.log(`Query schema was ${querySchemaName}, but database schema was ${dbSchemaName}.`);
+    throw new Error(`The query ${path.basename(initialInfo.queryPath)} cannot be run against the selected database (${dbItem.name}): their target languages are different. Please select a different database and try again.`);
+  }
+
+  const qlProgram: messages.QlProgram = {
+    // The project of the current document determines which library path
+    // we use. The `libraryPath` field in this server message is relative
+    // to the workspace root, not to the project root.
+    libraryPath: packConfig.libraryPath,
+    // Since we are compiling and running a query against a database,
+    // we use the database's DB scheme here instead of the DB scheme
+    // from the current document's project.
+    dbschemePath: dbItem.contents.dbSchemeUri.fsPath,
+    queryPath: initialInfo.queryPath
+  };
+
+  // Read the query metadata if possible, to use in the UI.
+  const metadata = await tryGetQueryMetadata(cliServer, qlProgram.queryPath);
+
+  let availableMlModels: cli.MlModelInfo[] = [];
+  if (!await cliServer.cliConstraints.supportsResolveMlModels()) {
+    void logger.log('Resolving ML models is unsupported by this version of the CLI. Running the query without any ML models.');
+  } else {
+    try {
+      availableMlModels = (await cliServer.resolveMlModels(diskWorkspaceFolders, initialInfo.queryPath)).models;
+      if (availableMlModels.length) {
+        void logger.log(`Found available ML models at the following paths: ${availableMlModels.map(x => `'${x.path}'`).join(', ')}.`);
+      } else {
+        void logger.log('Did not find any available ML models.');
+      }
+    } catch (e) {
+      const message = `Couldn't resolve available ML models for ${qlProgram.queryPath}. Running the ` +
+        `query without any ML models: ${e}.`;
+      void showAndLogErrorMessage(message);
+    }
+  }
+
+  const hasMetadataFile = (await dbItem.hasMetadataFile());
+  const query = new QueryInProgress(
+    path.join(queryStorageDir, initialInfo.id),
+    dbItem.databaseUri.fsPath,
+    hasMetadataFile,
+    packConfig.dbscheme,
+    initialInfo.quickEvalPosition,
+    metadata,
+    templates
+  );
+  await query.queryEvalInfo.createTimestampFile();
+
+  let upgradeDir: tmp.DirectoryResult | undefined;
+  try {
+    let upgradeQlo;
+    if (await cliServer.cliConstraints.supportsNonDestructiveUpgrades()) {
+      upgradeDir = await tmp.dir({ dir: upgradesTmpDir, unsafeCleanup: true });
+      upgradeQlo = await compileNonDestructiveUpgrade(qs, upgradeDir, query, qlProgram, dbItem, progress, token);
+    } else {
+      await checkDbschemeCompatibility(cliServer, qs, query, qlProgram, dbItem, progress, token);
+    }
+    let errors;
+    try {
+      errors = await query.compile(qs, qlProgram, progress, token);
+    } catch (e) {
+      if (e instanceof ResponseError && e.code == ErrorCodes.RequestCancelled) {
+        return createSyntheticResult(query, 'Query cancelled');
+      } else {
+        throw e;
+      }
+    }
+
+    if (errors.length === 0) {
+      const result = await query.run(qs, upgradeQlo, availableMlModels, dbItem, progress, token, queryInfo);
+      if (result.resultType !== messages.QueryResultType.SUCCESS) {
+        const message = result.message || 'Failed to run query';
+        void logger.log(message);
+        void showAndLogErrorMessage(message);
+      }
+      const message = formatLegacyMessage(result);
+
+      return {
+        query: query.queryEvalInfo,
+        message,
+        result,
+        successful: result.resultType == messages.QueryResultType.SUCCESS,
+        logFileLocation: result.logFileLocation,
+        dispose: () => {
+          qs.logger.removeAdditionalLogLocation(result.logFileLocation);
+        }
+      };
+    } else {
+      // Error dialogs are limited in size and scrollability,
+      // so we include a general description of the problem,
+      // and direct the user to the output window for the detailed compilation messages.
+      // However we don't show quick eval errors there so we need to display them anyway.
+      void qs.logger.log(
+        `Failed to compile query ${initialInfo.queryPath} against database scheme ${qlProgram.dbschemePath}:`,
+        { additionalLogLocation: query.queryEvalInfo.logPath }
+      );
+
+      const formattedMessages: string[] = [];
+
+      for (const error of errors) {
+        const message = error.message || '[no error message available]';
+        const formatted = `ERROR: ${message} (${error.position.fileName}:${error.position.line}:${error.position.column}:${error.position.endLine}:${error.position.endColumn})`;
+        formattedMessages.push(formatted);
+        void qs.logger.log(formatted, { additionalLogLocation: query.queryEvalInfo.logPath });
+      }
+      if (initialInfo.isQuickEval && formattedMessages.length <= 2) {
+        // If there are more than 2 error messages, they will not be displayed well in a popup
+        // and will be trimmed by the function displaying the error popup. Accordingly, we only
+        // try to show the errors if there are 2 or less, otherwise we direct the user to the log.
+        void showAndLogErrorMessage('Quick evaluation compilation failed: ' + formattedMessages.join('\n'));
+      } else {
+        void showAndLogErrorMessage((initialInfo.isQuickEval ? 'Quick evaluation' : 'Query') + compilationFailedErrorTail);
+      }
+      return createSyntheticResult(query, 'Query had compilation errors');
+    }
+  } finally {
+    try {
+      await upgradeDir?.cleanup();
+    } catch (e) {
+      void qs.logger.log(
+        `Could not clean up the upgrades dir. Reason: ${getErrorMessage(e)}`,
+        { additionalLogLocation: query.queryEvalInfo.logPath }
+      );
+    }
+  }
+}
+
+
+const compilationFailedErrorTail = ' compilation failed. Please make sure there are no errors in the query, the database is up to date,' +
+  ' and the query and database use the same target language. For more details on the error, go to View > Output,' +
+  ' and choose CodeQL Query Server from the dropdown.';
+
+export function formatLegacyMessage(result: messages.EvaluationResult) {
+  switch (result.resultType) {
+    case messages.QueryResultType.CANCELLATION:
+      return `cancelled after ${Math.round(result.evaluationTime / 1000)} seconds`;
+    case messages.QueryResultType.OOM:
+      return 'out of memory';
+    case messages.QueryResultType.SUCCESS:
+      return `finished in ${Math.round(result.evaluationTime / 1000)} seconds`;
+    case messages.QueryResultType.TIMEOUT:
+      return `timed out after ${Math.round(result.evaluationTime / 1000)} seconds`;
+    case messages.QueryResultType.OTHER_ERROR:
+    default:
+      return result.message ? `failed: ${result.message}` : 'failed';
+  }
+}
+
+/**
+ * Create a synthetic result for a query that failed to compile.
+ */
+function createSyntheticResult(
+  query: QueryInProgress,
+  message: string,
+): QueryWithResults {
+  return {
+    query: query.queryEvalInfo,
+    message,
+    result: {
+      evaluationTime: 0,
+      queryId: 0,
+      resultType: messages.QueryResultType.OTHER_ERROR,
+      message,
+      runId: 0,
+    },
+    successful: false,
+    dispose: () => { /**/ },
+  };
+}
+
+
+function createSimpleTemplates(templates: Record<string, string> | undefined): messages.TemplateDefinitions | undefined {
+  if (!templates) {
+    return undefined;
+  }
+  const result: messages.TemplateDefinitions = {};
+  for (const key of Object.keys(templates)) {
+    result[key] = {
+      values: {
+        tuples: [[{ stringValue: templates[key] }]]
+      }
+    };
+  }
+  return result;
+}

extensions/ql-vscode/src/legacy-query-server/upgrades.ts

@@ -0,0 +1,239 @@
+import * as vscode from 'vscode';
+import { getOnDiskWorkspaceFolders, showAndLogErrorMessage, tmpDir } from '../helpers';
+import { ProgressCallback, UserCancellationException } from '../commandRunner';
+import { logger } from '../logging';
+import * as messages from '../pure/legacy-messages';
+import * as qsClient from './queryserver-client';
+import * as tmp from 'tmp-promise';
+import * as path from 'path';
+import { DatabaseItem } from '../databases';
+
+/**
+ * Maximum number of lines to include from database upgrade message,
+ * to work around the fact that we can't guarantee a scrollable text
+ * box for it when displaying in dialog boxes.
+ */
+const MAX_UPGRADE_MESSAGE_LINES = 10;
+
+
+/**
+ * Compile a database upgrade sequence.
+ * Callers must check that this is valid with the current queryserver first.
+ */
+export async function compileDatabaseUpgradeSequence(
+  qs: qsClient.QueryServerClient,
+  dbItem: DatabaseItem,
+  resolvedSequence: string[],
+  currentUpgradeTmp: tmp.DirectoryResult,
+  progress: ProgressCallback,
+  token: vscode.CancellationToken
+): Promise<messages.CompileUpgradeSequenceResult> {
+  if (dbItem.contents === undefined || dbItem.contents.dbSchemeUri === undefined) {
+    throw new Error('Database is invalid, and cannot be upgraded.');
+  }
+  if (!await qs.cliServer.cliConstraints.supportsNonDestructiveUpgrades()) {
+    throw new Error('The version of codeql is too old to run non-destructive upgrades.');
+  }
+  // If possible just compile the upgrade sequence
+  return await qs.sendRequest(messages.compileUpgradeSequence, {
+    upgradeTempDir: currentUpgradeTmp.path,
+    upgradePaths: resolvedSequence
+  }, token, progress);
+}
+
+async function compileDatabaseUpgrade(
+  qs: qsClient.QueryServerClient,
+  dbItem: DatabaseItem,
+  targetDbScheme: string,
+  resolvedSequence: string[],
+  currentUpgradeTmp: tmp.DirectoryResult,
+  progress: ProgressCallback,
+  token: vscode.CancellationToken
+): Promise<messages.CompileUpgradeResult> {
+  if (!dbItem.contents?.dbSchemeUri) {
+    throw new Error('Database is invalid, and cannot be upgraded.');
+  }
+  // We have the upgrades we want but compileUpgrade
+  // requires searching for them.  So we use the parent directories of the upgrades
+  // as the upgrade path.
+  const parentDirs = resolvedSequence.map(dir => path.dirname(dir));
+  const uniqueParentDirs = new Set(parentDirs);
+  progress({
+    step: 1,
+    maxStep: 3,
+    message: 'Checking for database upgrades'
+  });
+  return qs.sendRequest(messages.compileUpgrade, {
+    upgrade: {
+      fromDbscheme: dbItem.contents.dbSchemeUri.fsPath,
+      toDbscheme: targetDbScheme,
+      additionalUpgrades: Array.from(uniqueParentDirs)
+    },
+    upgradeTempDir: currentUpgradeTmp.path,
+    singleFileUpgrades: true,
+  }, token, progress);
+}
+
+/**
+ * Checks whether the user wants to proceed with the upgrade.
+ * Reports errors to both the user and the console.
+ */
+async function checkAndConfirmDatabaseUpgrade(
+  compiled: messages.CompiledUpgrades,
+  db: DatabaseItem,
+  quiet: boolean
+): Promise<void> {
+
+  let descriptionMessage = '';
+  const descriptions = getUpgradeDescriptions(compiled);
+  for (const script of descriptions) {
+    descriptionMessage += `Would perform upgrade: ${script.description}\n`;
+    descriptionMessage += `\t-> Compatibility: ${script.compatibility}\n`;
+  }
+  void logger.log(descriptionMessage);
+
+
+  // If the quiet flag is set, do the upgrade without a popup.
+  if (quiet) {
+    return;
+  }
+
+  // Ask the user to confirm the upgrade.
+
+  const showLogItem: vscode.MessageItem = { title: 'No, Show Changes', isCloseAffordance: true };
+  const yesItem = { title: 'Yes', isCloseAffordance: false };
+  const noItem = { title: 'No', isCloseAffordance: true };
+  const dialogOptions: vscode.MessageItem[] = [yesItem, noItem];
+
+  let messageLines = descriptionMessage.split('\n');
+  if (messageLines.length > MAX_UPGRADE_MESSAGE_LINES) {
+    messageLines = messageLines.slice(0, MAX_UPGRADE_MESSAGE_LINES);
+    messageLines.push('The list of upgrades was truncated, click "No, Show Changes" to see the full list.');
+    dialogOptions.push(showLogItem);
+  }
+
+  const message = `Should the database ${db.databaseUri.fsPath} be upgraded?\n\n${messageLines.join('\n')}`;
+  const chosenItem = await vscode.window.showInformationMessage(message, { modal: true }, ...dialogOptions);
+
+  if (chosenItem === showLogItem) {
+    logger.outputChannel.show();
+  }
+
+  if (chosenItem !== yesItem) {
+    throw new UserCancellationException('User cancelled the database upgrade.');
+  }
+}
+
+/**
+ * Get the descriptions from a compiled upgrade
+ */
+function getUpgradeDescriptions(compiled: messages.CompiledUpgrades): messages.UpgradeDescription[] {
+  // We use the presence of compiledUpgradeFile to check
+  // if it is multifile or not. We need to explicitly check undefined
+  // as the types claim the empty string is a valid value
+  if (compiled.compiledUpgradeFile === undefined) {
+    return compiled.scripts.map(script => script.description);
+  } else {
+    return compiled.descriptions;
+  }
+}
+
+/**
+ * Command handler for 'Upgrade Database'.
+ * Attempts to upgrade the given database to the given target DB scheme, using the given directory of upgrades.
+ * First performs a dry-run and prompts the user to confirm the upgrade.
+ * Reports errors during compilation and evaluation of upgrades to the user.
+ */
+export async function upgradeDatabaseExplicit(
+  qs: qsClient.QueryServerClient,
+  dbItem: DatabaseItem,
+  progress: ProgressCallback,
+  token: vscode.CancellationToken,
+): Promise<messages.RunUpgradeResult | undefined> {
+
+  const searchPath: string[] = getOnDiskWorkspaceFolders();
+
+  if (!dbItem?.contents?.dbSchemeUri) {
+    throw new Error('Database is invalid, and cannot be upgraded.');
+  }
+  const upgradeInfo = await qs.cliServer.resolveUpgrades(
+    dbItem.contents.dbSchemeUri.fsPath,
+    searchPath,
+    false
+  );
+
+  const { scripts, finalDbscheme } = upgradeInfo;
+
+  if (finalDbscheme === undefined) {
+    throw new Error('Could not determine target dbscheme to upgrade to.');
+  }
+  const currentUpgradeTmp = await tmp.dir({ dir: tmpDir.name, prefix: 'upgrade_', keep: false, unsafeCleanup: true });
+  try {
+    let compileUpgradeResult: messages.CompileUpgradeResult;
+    try {
+      compileUpgradeResult = await compileDatabaseUpgrade(qs, dbItem, finalDbscheme, scripts, currentUpgradeTmp, progress, token);
+    }
+    catch (e) {
+      void showAndLogErrorMessage(`Compilation of database upgrades failed: ${e}`);
+      return;
+    }
+    finally {
+      void qs.logger.log('Done compiling database upgrade.');
+    }
+
+    if (!compileUpgradeResult.compiledUpgrades) {
+      const error = compileUpgradeResult.error || '[no error message available]';
+      void showAndLogErrorMessage(`Compilation of database upgrades failed: ${error}`);
+      return;
+    }
+
+    await checkAndConfirmDatabaseUpgrade(compileUpgradeResult.compiledUpgrades, dbItem, qs.cliServer.quiet);
+
+    try {
+      void qs.logger.log('Running the following database upgrade:');
+
+      getUpgradeDescriptions(compileUpgradeResult.compiledUpgrades).map(s => s.description).join('\n');
+      const result = await runDatabaseUpgrade(qs, dbItem, compileUpgradeResult.compiledUpgrades, progress, token);
+
+      // TODO Can remove the next lines when https://github.com/github/codeql-team/issues/1241 is fixed
+      // restart the query server to avoid a bug in the CLI where the upgrade is applied, but the old dbscheme
+      // is still cached in memory.
+
+      await qs.restartQueryServer(progress, token);
+      return result;
+    }
+    catch (e) {
+      void showAndLogErrorMessage(`Database upgrade failed: ${e}`);
+      return;
+    } finally {
+      void qs.logger.log('Done running database upgrade.');
+    }
+  } finally {
+    await currentUpgradeTmp.cleanup();
+  }
+}
+
+async function runDatabaseUpgrade(
+  qs: qsClient.QueryServerClient,
+  db: DatabaseItem,
+  upgrades: messages.CompiledUpgrades,
+  progress: ProgressCallback,
+  token: vscode.CancellationToken,
+): Promise<messages.RunUpgradeResult> {
+
+  if (db.contents === undefined || db.contents.datasetUri === undefined) {
+    throw new Error('Can\'t upgrade an invalid database.');
+  }
+  const database: messages.Dataset = {
+    dbDir: db.contents.datasetUri.fsPath,
+    workingSet: 'default'
+  };
+
+  const params: messages.RunUpgradeParams = {
+    db: database,
+    timeoutSecs: qs.config.timeoutSecs,
+    toRun: upgrades
+  };
+
+  return qs.sendRequest(messages.runUpgrade, params, token, progress);
+}

extensions/ql-vscode/src/log-insights/join-order.ts

@@ -0,0 +1,460 @@
+import * as I from 'immutable';
+import { EvaluationLogProblemReporter, EvaluationLogScanner, EvaluationLogScannerProvider } from './log-scanner';
+import { InLayer, ComputeRecursive, SummaryEvent, PipelineRun, ComputeSimple } from './log-summary';
+
+const DEFAULT_WARNING_THRESHOLD = 50;
+
+/**
+ * Like `max`, but returns 0 if no meaningful maximum can be computed.
+ */
+function safeMax(it?: Iterable<number>) {
+  const m = Math.max(...(it || []));
+  return Number.isFinite(m) ? m : 0;
+}
+
+/**
+ * Compute a key for the maps that that is sent to report generation.
+ * Should only be used on events that are known to define queryCausingWork.
+ */
+function makeKey(
+  queryCausingWork: string | undefined,
+  predicate: string,
+  suffix = ''
+): string {
+  if (queryCausingWork === undefined) {
+    throw new Error(
+      'queryCausingWork was not defined on an event we expected it to be defined for!'
+    );
+  }
+  return `${queryCausingWork}:${predicate}${suffix ? ' ' + suffix : ''}`;
+}
+
+const DEPENDENT_PREDICATES_REGEXP = (() => {
+  const regexps = [
+    // SCAN id
+    String.raw`SCAN\s+([0-9a-zA-Z:#_]+)\s`,
+    // JOIN id WITH id
+    String.raw`JOIN\s+([0-9a-zA-Z:#_]+)\s+WITH\s+([0-9a-zA-Z:#_]+)\s`,
+    // AGGREGATE id, id
+    String.raw`AGGREGATE\s+([0-9a-zA-Z:#_]+)\s*,\s+([0-9a-zA-Z:#_]+)`,
+    // id AND NOT id
+    String.raw`([0-9a-zA-Z:#_]+)\s+AND\s+NOT\s+([0-9a-zA-Z:#_]+)`,
+    // INVOKE HIGHER-ORDER RELATION rel ON <id, ..., id>
+    String.raw`INVOKE\s+HIGHER-ORDER\s+RELATION\s[^\s]+\sON\s+<([0-9a-zA-Z:#_<>]+)((?:,[0-9a-zA-Z:#_<>]+)*)>`,
+    // SELECT id
+    String.raw`SELECT\s+([0-9a-zA-Z:#_]+)`
+  ];
+  return new RegExp(
+    `${String.raw`\{[0-9]+\}\s+[0-9a-zA-Z]+\s=\s(?:` + regexps.join('|')})`
+  );
+})();
+
+function getDependentPredicates(operations: string[]): I.List<string> {
+  return I.List(operations).flatMap(operation => {
+    const matches = DEPENDENT_PREDICATES_REGEXP.exec(operation.trim());
+    if (matches !== null) {
+      return I.List(matches)
+        .rest() // Skip the first group as it's just the entire string
+        .filter(x => !!x && !x.match('r[0-9]+|PRIMITIVE')) // Only keep the references to predicates.
+        .flatMap(x => x.split(',')) // Group 2 in the INVOKE HIGHER_ORDER RELATION case is a comma-separated list of identifiers.
+        .filter(x => !!x); // Remove empty strings
+    } else {
+      return I.List();
+    }
+  });
+}
+
+function getMainHash(event: InLayer | ComputeRecursive): string {
+  switch (event.evaluationStrategy) {
+    case 'IN_LAYER':
+      return event.mainHash;
+    case 'COMPUTE_RECURSIVE':
+      return event.raHash;
+  }
+}
+
+/**
+ * Sum arrays a and b element-wise. The shorter array is padded with 0s if the arrays are not the same length.
+ */
+function pointwiseSum(a: Int32Array, b: Int32Array, problemReporter: EvaluationLogProblemReporter): Int32Array {
+  function reportIfInconsistent(ai: number, bi: number) {
+    if (ai === -1 && bi !== -1) {
+      problemReporter.log(
+        `Operation was not evaluated in the first pipeline, but it was evaluated in the accumulated pipeline (with tuple count ${bi}).`
+      );
+    }
+    if (ai !== -1 && bi === -1) {
+      problemReporter.log(
+        `Operation was evaluated in the first pipeline (with tuple count ${ai}), but it was not evaluated in the accumulated pipeline.`
+      );
+    }
+  }
+
+  const length = Math.max(a.length, b.length);
+  const result = new Int32Array(length);
+  for (let i = 0; i < length; i++) {
+    const ai = a[i] || 0;
+    const bi = b[i] || 0;
+    // -1 is used to represent the absence of a tuple count for a line in the pretty-printed RA (e.g. an empty line), so we ignore those.
+    if (i < a.length && i < b.length && (ai === -1 || bi === -1)) {
+      result[i] = -1;
+      reportIfInconsistent(ai, bi);
+    } else {
+      result[i] = ai + bi;
+    }
+  }
+  return result;
+}
+
+function pushValue<K, V>(m: Map<K, V[]>, k: K, v: V) {
+  if (!m.has(k)) {
+    m.set(k, []);
+  }
+  m.get(k)!.push(v);
+  return m;
+}
+
+function computeJoinOrderBadness(
+  maxTupleCount: number,
+  maxDependentPredicateSize: number,
+  resultSize: number
+): number {
+  return maxTupleCount / Math.max(maxDependentPredicateSize, resultSize);
+}
+
+/**
+ * A bucket contains the pointwise sum of the tuple counts, result sizes and dependent predicate sizes
+ * For each (predicate, order) in an SCC, we will compute a bucket.
+ */
+interface Bucket {
+  tupleCounts: Int32Array;
+  resultSize: number;
+  dependentPredicateSizes: I.Map<string, number>;
+}
+
+class JoinOrderScanner implements EvaluationLogScanner {
+  // Map a predicate hash to its result size
+  private readonly predicateSizes = new Map<string, number>();
+  private readonly layerEvents = new Map<string, (ComputeRecursive | InLayer)[]>();
+  // Map a key of the form 'query-with-demand : predicate name' to its badness input.
+  private readonly maxTupleCountMap = new Map<string, number[]>();
+  private readonly resultSizeMap = new Map<string, number[]>();
+  private readonly maxDependentPredicateSizeMap = new Map<string, number[]>();
+  private readonly joinOrderMetricMap = new Map<string, number>();
+
+  constructor(
+    private readonly problemReporter: EvaluationLogProblemReporter,
+    private readonly warningThreshold: number) {
+  }
+
+  public onEvent(event: SummaryEvent): void {
+    if (
+      event.completionType !== undefined &&
+      event.completionType !== 'SUCCESS'
+    ) {
+      return; // Skip any evaluation that wasn't successful
+    }
+
+    this.recordPredicateSizes(event);
+    this.computeBadnessMetric(event);
+  }
+
+  public onDone(): void {
+    void this;
+  }
+
+  private recordPredicateSizes(event: SummaryEvent): void {
+    switch (event.evaluationStrategy) {
+      case 'EXTENSIONAL':
+      case 'COMPUTED_EXTENSIONAL':
+      case 'COMPUTE_SIMPLE':
+      case 'CACHACA':
+      case 'CACHE_HIT': {
+        this.predicateSizes.set(event.raHash, event.resultSize);
+        break;
+      }
+      case 'SENTINEL_EMPTY': {
+        this.predicateSizes.set(event.raHash, 0);
+        break;
+      }
+      case 'COMPUTE_RECURSIVE':
+      case 'IN_LAYER': {
+        this.predicateSizes.set(event.raHash, event.resultSize);
+        // layerEvents are indexed by the mainHash.
+        const hash = getMainHash(event);
+        if (!this.layerEvents.has(hash)) {
+          this.layerEvents.set(hash, []);
+        }
+        this.layerEvents.get(hash)!.push(event);
+        break;
+      }
+    }
+  }
+
+  private reportProblemIfNecessary(event: SummaryEvent, iteration: number, metric: number): void {
+    if (metric >= this.warningThreshold) {
+      this.problemReporter.reportProblem(event.predicateName, event.raHash, iteration,
+        `Relation '${event.predicateName}' has an inefficient join order. Its join order metric is ${metric.toFixed(2)}, which is larger than the threshold of ${this.warningThreshold.toFixed(2)}.`);
+    }
+  }
+
+  private computeBadnessMetric(event: SummaryEvent): void {
+    if (
+      event.completionType !== undefined &&
+      event.completionType !== 'SUCCESS'
+    ) {
+      return; // Skip any evaluation that wasn't successful
+    }
+    switch (event.evaluationStrategy) {
+      case 'COMPUTE_SIMPLE': {
+        if (!event.pipelineRuns) {
+          // skip if the optional pipelineRuns field is not present.
+          break;
+        }
+        // Compute the badness metric for a non-recursive predicate. The metric in this case is defined as:
+        // badness = (max tuple count in the pipeline) / (largest predicate this pipeline depends on)
+        const key = makeKey(event.queryCausingWork, event.predicateName);
+        const resultSize = event.resultSize;
+
+        // There is only one entry in `pipelineRuns` if it's a non-recursive predicate.
+        const { maxTupleCount, maxDependentPredicateSize } =
+          this.badnessInputsForNonRecursiveDelta(event.pipelineRuns[0], event);
+
+        if (maxDependentPredicateSize > 0) {
+          pushValue(this.maxTupleCountMap, key, maxTupleCount);
+          pushValue(this.resultSizeMap, key, resultSize);
+          pushValue(
+            this.maxDependentPredicateSizeMap,
+            key,
+            maxDependentPredicateSize
+          );
+          const metric = computeJoinOrderBadness(maxTupleCount, maxDependentPredicateSize, resultSize!);
+          this.joinOrderMetricMap.set(key, metric);
+          this.reportProblemIfNecessary(event, 0, metric);
+        }
+        break;
+      }
+
+      case 'COMPUTE_RECURSIVE': {
+        // Compute the badness metric for a recursive predicate for each ordering.
+        const sccMetricInput = this.badnessInputsForRecursiveDelta(event);
+        // Loop through each predicate in the SCC
+        sccMetricInput.forEach((buckets, predicate) => {
+          // Loop through each ordering of the predicate
+          buckets.forEach((bucket, raReference) => {
+            // Format the key as demanding-query:name (ordering)
+            const key = makeKey(
+              event.queryCausingWork,
+              predicate,
+              `(${raReference})`
+            );
+            const maxTupleCount = Math.max(...bucket.tupleCounts);
+            const resultSize = bucket.resultSize;
+            const maxDependentPredicateSize = Math.max(
+              ...bucket.dependentPredicateSizes.values()
+            );
+
+            if (maxDependentPredicateSize > 0) {
+              pushValue(this.maxTupleCountMap, key, maxTupleCount);
+              pushValue(this.resultSizeMap, key, resultSize);
+              pushValue(
+                this.maxDependentPredicateSizeMap,
+                key,
+                maxDependentPredicateSize
+              );
+              const metric = computeJoinOrderBadness(maxTupleCount, maxDependentPredicateSize, resultSize);
+              const oldMetric = this.joinOrderMetricMap.get(key);
+              if ((oldMetric === undefined) || (metric > oldMetric)) {
+                this.joinOrderMetricMap.set(key, metric);
+              }
+            }
+          });
+        });
+        break;
+      }
+    }
+  }
+
+  /**
+   * Iterate through an SCC with main node `event`.
+   */
+  private iterateSCC(
+    event: ComputeRecursive,
+    func: (
+      inLayerEvent: ComputeRecursive | InLayer,
+      run: PipelineRun,
+      iteration: number
+    ) => void
+  ): void {
+    const sccEvents = this.layerEvents.get(event.raHash)!;
+    const nextPipeline: number[] = new Array(sccEvents.length).fill(0);
+
+    const maxIteration = Math.max(
+      ...sccEvents.map(e => e.predicateIterationMillis.length)
+    );
+
+    for (let iteration = 0; iteration < maxIteration; ++iteration) {
+      // Loop through each predicate in this iteration
+      for (let predicate = 0; predicate < sccEvents.length; ++predicate) {
+        const inLayerEvent = sccEvents[predicate];
+        const iterationTime =
+          inLayerEvent.predicateIterationMillis.length <= iteration
+            ? -1
+            : inLayerEvent.predicateIterationMillis[iteration];
+        if (iterationTime != -1) {
+          const run: PipelineRun =
+            inLayerEvent.pipelineRuns[nextPipeline[predicate]++];
+          func(inLayerEvent, run, iteration);
+        }
+      }
+    }
+  }
+
+  /**
+   * Compute the maximum tuple count and maximum dependent predicate size for a non-recursive pipeline
+   */
+  private badnessInputsForNonRecursiveDelta(
+    pipelineRun: PipelineRun,
+    event: ComputeSimple
+  ): { maxTupleCount: number; maxDependentPredicateSize: number } {
+    const dependentPredicateSizes = Object.values(event.dependencies).map(hash =>
+      this.predicateSizes.get(hash) ?? 0  // Should always be present, but zero is a safe default.
+    );
+    const maxDependentPredicateSize = safeMax(dependentPredicateSizes);
+    return {
+      maxTupleCount: safeMax(pipelineRun.counts),
+      maxDependentPredicateSize: maxDependentPredicateSize
+    };
+  }
+
+  private prevDeltaSizes(event: ComputeRecursive, predicate: string, i: number) {
+    // If an iteration isn't present in the map it means it was skipped because the optimizer
+    // inferred that it was empty. So its size is 0.
+    return this.curDeltaSizes(event, predicate, i - 1);
+  }
+
+  private curDeltaSizes(event: ComputeRecursive, predicate: string, i: number) {
+    // If an iteration isn't present in the map it means it was skipped because the optimizer
+    // inferred that it was empty. So its size is 0.
+    return (
+      this.layerEvents.get(event.raHash)?.find(x => x.predicateName === predicate)?.deltaSizes[i] ?? 0
+    );
+  }
+
+  /**
+   * Compute the metric dependent predicate sizes and the result size for a predicate in an SCC.
+   */
+  private badnessInputsForLayer(
+    event: ComputeRecursive,
+    inLayerEvent: InLayer | ComputeRecursive,
+    raReference: string,
+    iteration: number
+  ) {
+    const dependentPredicates = getDependentPredicates(
+      inLayerEvent.ra[raReference]
+    );
+    let dependentPredicateSizes: I.Map<string, number>;
+    // We treat the base case as a non-recursive pipeline. In that case, the dependent predicates are
+    // the dependencies of the base case and the cur_deltas.
+    if (raReference === 'base') {
+      dependentPredicateSizes = I.Map(
+        dependentPredicates.map((pred): [string, number] => {
+          // A base case cannot contain a `prev_delta`, but it can contain a `cur_delta`.
+          let size = 0;
+          if (pred.endsWith('#cur_delta')) {
+            size = this.curDeltaSizes(
+              event,
+              pred.slice(0, -'#cur_delta'.length),
+              iteration
+            );
+          } else {
+            const hash = event.dependencies[pred];
+            size = this.predicateSizes.get(hash)!;
+          }
+          return [pred, size];
+        })
+      );
+    } else {
+      // It's a non-base case in a recursive pipeline. In that case, the dependent predicates are
+      // only the prev_deltas.
+      dependentPredicateSizes = I.Map(
+        dependentPredicates
+          .flatMap(pred => {
+            // If it's actually a prev_delta
+            if (pred.endsWith('#prev_delta')) {
+              // Return the predicate without the #prev_delta suffix.
+              return [pred.slice(0, -'#prev_delta'.length)];
+            } else {
+              // Not a recursive delta. Skip it.
+              return [];
+            }
+          })
+          .map((prev): [string, number] => {
+            const size = this.prevDeltaSizes(event, prev, iteration);
+            return [prev, size];
+          })
+      );
+    }
+
+    const deltaSize = inLayerEvent.deltaSizes[iteration];
+    return { dependentPredicateSizes, deltaSize };
+  }
+
+  /**
+   * Compute the metric input for all the events in a SCC that starts with main node `event`
+   */
+  private badnessInputsForRecursiveDelta(event: ComputeRecursive): Map<string, Map<string, Bucket>> {
+    // nameToOrderToBucket : predicate name -> ordering (i.e., standard, order_500000, etc.) -> bucket
+    const nameToOrderToBucket = new Map<string, Map<string, Bucket>>();
+
+    // Iterate through the SCC and compute the metric inputs
+    this.iterateSCC(event, (inLayerEvent, run, iteration) => {
+      const raReference = run.raReference;
+      const predicateName = inLayerEvent.predicateName;
+      if (!nameToOrderToBucket.has(predicateName)) {
+        nameToOrderToBucket.set(predicateName, new Map());
+      }
+      const orderTobucket = nameToOrderToBucket.get(predicateName)!;
+      if (!orderTobucket.has(raReference)) {
+        orderTobucket.set(raReference, {
+          tupleCounts: new Int32Array(0),
+          resultSize: 0,
+          dependentPredicateSizes: I.Map()
+        });
+      }
+
+      const { dependentPredicateSizes, deltaSize } = this.badnessInputsForLayer(
+        event,
+        inLayerEvent,
+        raReference,
+        iteration
+      );
+
+      const bucket = orderTobucket.get(raReference)!;
+      // Pointwise sum the tuple counts
+      const newTupleCounts = pointwiseSum(
+        bucket.tupleCounts,
+        new Int32Array(run.counts),
+        this.problemReporter
+      );
+      const resultSize = bucket.resultSize + deltaSize;
+      // Pointwise sum the deltas.
+      const newDependentPredicateSizes = bucket.dependentPredicateSizes.mergeWith(
+        (oldSize, newSize) => oldSize + newSize,
+        dependentPredicateSizes
+      );
+      orderTobucket.set(raReference, {
+        tupleCounts: newTupleCounts,
+        resultSize: resultSize,
+        dependentPredicateSizes: newDependentPredicateSizes
+      });
+    });
+    return nameToOrderToBucket;
+  }
+}
+
+export class JoinOrderScannerProvider implements EvaluationLogScannerProvider {
+  public createScanner(problemReporter: EvaluationLogProblemReporter): EvaluationLogScanner {
+    return new JoinOrderScanner(problemReporter, DEFAULT_WARNING_THRESHOLD);
+  }
+}

extensions/ql-vscode/src/log-insights/jsonl-reader.ts

@@ -0,0 +1,23 @@
+import * as fs from 'fs-extra';
+
+/**
+ * Read a file consisting of multiple JSON objects. Each object is separated from the previous one
+ * by a double newline sequence. This is basically a more human-readable form of JSONL.
+ *
+ * The current implementation reads the entire text of the document into memory, but in the future
+ * it will stream the document to improve the performance with large documents.
+ *
+ * @param path The path to the file.
+ * @param handler Callback to be invoked for each top-level JSON object in order.
+ */
+export async function readJsonlFile(path: string, handler: (value: any) => Promise<void>): Promise<void> {
+  const logSummary = await fs.readFile(path, 'utf-8');
+
+  // Remove newline delimiters because summary is in .jsonl format.
+  const jsonSummaryObjects: string[] = logSummary.split(/\r?\n\r?\n/g);
+
+  for (const obj of jsonSummaryObjects) {
+    const jsonObj = JSON.parse(obj);
+    await handler(jsonObj);
+  }
+}

extensions/ql-vscode/src/log-insights/log-scanner-service.ts

@@ -0,0 +1,109 @@
+import { Diagnostic, DiagnosticSeverity, languages, Range, Uri } from 'vscode';
+import { DisposableObject } from '../pure/disposable-object';
+import { QueryHistoryManager } from '../query-history';
+import { QueryHistoryInfo } from '../query-history-info';
+import { EvaluationLogProblemReporter, EvaluationLogScannerSet } from './log-scanner';
+import { PipelineInfo, SummarySymbols } from './summary-parser';
+import * as fs from 'fs-extra';
+import { logger } from '../logging';
+
+/**
+ * Compute the key used to find a predicate in the summary symbols.
+ * @param name The name of the predicate.
+ * @param raHash The RA hash of the predicate.
+ * @returns The key of the predicate, consisting of `name@shortHash`, where `shortHash` is the first
+ * eight characters of `raHash`.
+ */
+function predicateSymbolKey(name: string, raHash: string): string {
+  return `${name}@${raHash.substring(0, 8)}`;
+}
+
+/**
+ * Implementation of `EvaluationLogProblemReporter` that generates `Diagnostic` objects to display
+ * in the VS Code "Problems" view.
+ */
+class ProblemReporter implements EvaluationLogProblemReporter {
+  public readonly diagnostics: Diagnostic[] = [];
+
+  constructor(private readonly symbols: SummarySymbols | undefined) {
+  }
+
+  public reportProblem(predicateName: string, raHash: string, iteration: number, message: string): void {
+    const nameWithHash = predicateSymbolKey(predicateName, raHash);
+    const predicateSymbol = this.symbols?.predicates[nameWithHash];
+    let predicateInfo: PipelineInfo | undefined = undefined;
+    if (predicateSymbol !== undefined) {
+      predicateInfo = predicateSymbol.iterations[iteration];
+    }
+    if (predicateInfo !== undefined) {
+      const range = new Range(predicateInfo.raStartLine, 0, predicateInfo.raEndLine + 1, 0);
+      this.diagnostics.push(new Diagnostic(range, message, DiagnosticSeverity.Error));
+    }
+  }
+
+  public log(message: string): void {
+    void logger.log(message);
+  }
+}
+
+export class LogScannerService extends DisposableObject {
+  public readonly scanners = new EvaluationLogScannerSet();
+  private readonly diagnosticCollection = this.push(languages.createDiagnosticCollection('ql-eval-log'));
+  private currentItem: QueryHistoryInfo | undefined = undefined;
+
+  constructor(qhm: QueryHistoryManager) {
+    super();
+
+    this.push(qhm.onDidChangeCurrentQueryItem(async (item) => {
+      if (item !== this.currentItem) {
+        this.currentItem = item;
+        await this.scanEvalLog(item);
+      }
+    }));
+
+    this.push(qhm.onDidCompleteQuery(async (item) => {
+      if (item === this.currentItem) {
+        await this.scanEvalLog(item);
+      }
+    }));
+  }
+
+  /**
+   * Scan the evaluation log for a query, and report any diagnostics.
+   *
+   * @param query The query whose log is to be scanned.
+   */
+  public async scanEvalLog(
+    query: QueryHistoryInfo | undefined
+  ): Promise<void> {
+    this.diagnosticCollection.clear();
+
+    if ((query?.t !== 'local')
+      || (query.evalLogSummaryLocation === undefined)
+      || (query.jsonEvalLogSummaryLocation === undefined)) {
+      return;
+    }
+
+    const diagnostics = await this.scanLog(query.jsonEvalLogSummaryLocation, query.evalLogSummarySymbolsLocation);
+    const uri = Uri.file(query.evalLogSummaryLocation);
+    this.diagnosticCollection.set(uri, diagnostics);
+  }
+
+  /**
+   * Scan the evaluator summary log for problems, using the scanners for all registered providers.
+   * @param jsonSummaryLocation The file path of the JSON summary log.
+   * @param symbolsLocation The file path of the symbols file for the human-readable log summary.
+   * @returns An array of `Diagnostic`s representing the problems found by scanners.
+   */
+  private async scanLog(jsonSummaryLocation: string, symbolsLocation: string | undefined): Promise<Diagnostic[]> {
+    let symbols: SummarySymbols | undefined = undefined;
+    if (symbolsLocation !== undefined) {
+      symbols = JSON.parse(await fs.readFile(symbolsLocation, { encoding: 'utf-8' }));
+    }
+    const problemReporter = new ProblemReporter(symbols);
+
+    await this.scanners.scanLog(jsonSummaryLocation, problemReporter);
+
+    return problemReporter.diagnostics;
+  }
+}

extensions/ql-vscode/src/log-insights/log-scanner.ts

@@ -0,0 +1,103 @@
+import { SummaryEvent } from './log-summary';
+import { readJsonlFile } from './jsonl-reader';
+
+/**
+ * Callback interface used to report diagnostics from a log scanner.
+ */
+export interface EvaluationLogProblemReporter {
+  /**
+   * Report a potential problem detected in the evaluation log.
+   *
+   * @param predicateName The mangled name of the predicate with the problem.
+   * @param raHash The RA hash of the predicate with the problem.
+   * @param iteration The iteration number with the problem. For a non-recursive predicate, this
+   * must be zero.
+   * @param message The problem message.
+   */
+  reportProblem(predicateName: string, raHash: string, iteration: number, message: string): void;
+
+  /**
+   * Log a message about a problem in the implementation of the scanner. These will typically be
+   * displayed separate from any problems reported via `reportProblem()`.
+   */
+  log(message: string): void;
+}
+
+/**
+ * Interface implemented by a log scanner. Instances are created via
+ * `EvaluationLogScannerProvider.createScanner()`.
+ */
+export interface EvaluationLogScanner {
+  /**
+   * Called for each event in the log summary, in order. The implementation can report problems via
+   * the `EvaluationLogProblemReporter` interface that was supplied to `createScanner()`.
+   * @param event The log summary event.
+   */
+  onEvent(event: SummaryEvent): void;
+  /**
+   * Called after all events in the log summary have been processed. The implementation can report
+   * problems via the `EvaluationLogProblemReporter` interface that was supplied to
+   * `createScanner()`.
+   */
+  onDone(): void;
+}
+
+/**
+ * A factory for log scanners. When a log is to be scanned, all registered
+ * `EvaluationLogScannerProviders` will be asked to create a new instance of `EvaluationLogScanner`
+ * to do the scanning.
+ */
+export interface EvaluationLogScannerProvider {
+  /**
+   * Create a new instance of `EvaluationLogScanner` to scan a single summary log.
+   * @param problemReporter Callback interface for reporting any problems discovered.
+   */
+  createScanner(problemReporter: EvaluationLogProblemReporter): EvaluationLogScanner;
+}
+
+/**
+ * Same as VSCode's `Disposable`, but avoids a dependency on VS Code.
+ */
+export interface Disposable {
+  dispose(): void;
+}
+
+export class EvaluationLogScannerSet {
+  private readonly scannerProviders = new Map<number, EvaluationLogScannerProvider>();
+  private nextScannerProviderId = 0;
+
+  /**
+   * Register a provider that can create instances of `EvaluationLogScanner` to scan evaluation logs
+   * for problems.
+   * @param provider The provider.
+   * @returns A `Disposable` that, when disposed, will unregister the provider.
+   */
+  public registerLogScannerProvider(provider: EvaluationLogScannerProvider): Disposable {
+    const id = this.nextScannerProviderId;
+    this.nextScannerProviderId++;
+
+    this.scannerProviders.set(id, provider);
+    return {
+      dispose: () => {
+        this.scannerProviders.delete(id);
+      }
+    };
+  }
+
+  /**
+   * Scan the evaluator summary log for problems, using the scanners for all registered providers.
+   * @param jsonSummaryLocation The file path of the JSON summary log.
+   * @param problemReporter Callback interface for reporting any problems discovered.
+   */
+  public async scanLog(jsonSummaryLocation: string, problemReporter: EvaluationLogProblemReporter): Promise<void> {
+    const scanners = [...this.scannerProviders.values()].map(p => p.createScanner(problemReporter));
+
+    await readJsonlFile(jsonSummaryLocation, async obj => {
+      scanners.forEach(scanner => {
+        scanner.onEvent(obj);
+      });
+    });
+
+    scanners.forEach(scanner => scanner.onDone());
+  }
+}

extensions/ql-vscode/src/log-insights/log-summary.ts

@@ -0,0 +1,93 @@
+export interface PipelineRun {
+  raReference: string;
+  counts: number[];
+  duplicationPercentages: number[];
+}
+
+export interface Ra {
+  [key: string]: string[];
+}
+
+export type EvaluationStrategy =
+  'COMPUTE_SIMPLE' |
+  'COMPUTE_RECURSIVE' |
+  'IN_LAYER' |
+  'COMPUTED_EXTENSIONAL' |
+  'EXTENSIONAL' |
+  'SENTINEL_EMPTY' |
+  'CACHACA' |
+  'CACHE_HIT';
+
+interface SummaryEventBase {
+  evaluationStrategy: EvaluationStrategy;
+  predicateName: string;
+  raHash: string;
+  appearsAs: { [key: string]: { [key: string]: number[] } };
+  completionType?: string;
+}
+
+interface ResultEventBase extends SummaryEventBase {
+  resultSize: number;
+}
+
+export interface ComputeSimple extends ResultEventBase {
+  evaluationStrategy: 'COMPUTE_SIMPLE';
+  ra: Ra;
+  pipelineRuns?: [PipelineRun];
+  queryCausingWork?: string;
+  dependencies: { [key: string]: string };
+}
+
+export interface ComputeRecursive extends ResultEventBase {
+  evaluationStrategy: 'COMPUTE_RECURSIVE';
+  deltaSizes: number[];
+  ra: Ra;
+  pipelineRuns: PipelineRun[];
+  queryCausingWork?: string;
+  dependencies: { [key: string]: string };
+  predicateIterationMillis: number[];
+}
+
+export interface InLayer extends ResultEventBase {
+  evaluationStrategy: 'IN_LAYER';
+  deltaSizes: number[];
+  ra: Ra;
+  pipelineRuns: PipelineRun[];
+  queryCausingWork?: string;
+  mainHash: string;
+  predicateIterationMillis: number[];
+}
+
+export interface ComputedExtensional extends ResultEventBase {
+  evaluationStrategy: 'COMPUTED_EXTENSIONAL';
+  queryCausingWork?: string;
+}
+
+export interface NonComputedExtensional extends ResultEventBase {
+  evaluationStrategy: 'EXTENSIONAL';
+  queryCausingWork?: string;
+}
+
+export interface SentinelEmpty extends SummaryEventBase {
+  evaluationStrategy: 'SENTINEL_EMPTY';
+  sentinelRaHash: string;
+}
+
+export interface Cachaca extends ResultEventBase {
+  evaluationStrategy: 'CACHACA';
+}
+
+export interface CacheHit extends ResultEventBase {
+  evaluationStrategy: 'CACHE_HIT';
+}
+
+export type Extensional = ComputedExtensional | NonComputedExtensional;
+
+export type SummaryEvent =
+  | ComputeSimple
+  | ComputeRecursive
+  | InLayer
+  | Extensional
+  | SentinelEmpty
+  | Cachaca
+  | CacheHit;

extensions/ql-vscode/src/log-insights/summary-language-support.ts

@@ -0,0 +1,154 @@
+import * as fs from 'fs-extra';
+import { RawSourceMap, SourceMapConsumer } from 'source-map';
+import { commands, Position, Selection, TextDocument, TextEditor, TextEditorRevealType, TextEditorSelectionChangeEvent, ViewColumn, window, workspace } from 'vscode';
+import { DisposableObject } from '../pure/disposable-object';
+import { commandRunner } from '../commandRunner';
+import { logger } from '../logging';
+import { getErrorMessage } from '../pure/helpers-pure';
+
+/** A `Position` within a specified file on disk. */
+interface PositionInFile {
+  filePath: string;
+  position: Position;
+}
+
+/**
+ * Opens the specified source location in a text editor.
+ * @param position The position (including file path) to show.
+ */
+async function showSourceLocation(position: PositionInFile): Promise<void> {
+  const document = await workspace.openTextDocument(position.filePath);
+  const editor = await window.showTextDocument(document, ViewColumn.Active);
+  editor.selection = new Selection(position.position, position.position);
+  editor.revealRange(editor.selection, TextEditorRevealType.InCenterIfOutsideViewport);
+}
+
+/**
+ * Simple language support for human-readable evaluator log summaries.
+ *
+ * This class implements the `codeQL.gotoQL` command, which jumps from RA code to the corresponding
+ * QL code that generated it. It also tracks the current selection and active editor to enable and
+ * disable that command based on whether there is a QL mapping for the current selection.
+ */
+export class SummaryLanguageSupport extends DisposableObject {
+  /**
+   * The last `TextDocument` (with language `ql-summary`) for which we tried to find a sourcemap, or
+   * `undefined` if we have not seen such a document yet.
+   */
+  private lastDocument: TextDocument | undefined = undefined;
+  /**
+   * The sourcemap for `lastDocument`, or `undefined` if there was no such sourcemap or document.
+   */
+  private sourceMap: SourceMapConsumer | undefined = undefined;
+
+  constructor() {
+    super();
+
+    this.push(window.onDidChangeActiveTextEditor(this.handleDidChangeActiveTextEditor));
+    this.push(window.onDidChangeTextEditorSelection(this.handleDidChangeTextEditorSelection));
+    this.push(workspace.onDidCloseTextDocument(this.handleDidCloseTextDocument));
+
+    this.push(commandRunner('codeQL.gotoQL', this.handleGotoQL));
+  }
+
+  /**
+   * Gets the location of the QL code that generated the RA at the current selection in the active
+   * editor, or `undefined` if there is no mapping.
+   */
+  private async getQLSourceLocation(): Promise<PositionInFile | undefined> {
+    const editor = window.activeTextEditor;
+    if (editor === undefined) {
+      return undefined;
+    }
+
+    const document = editor.document;
+    if (document.languageId !== 'ql-summary') {
+      return undefined;
+    }
+
+    if (document.uri.scheme !== 'file') {
+      return undefined;
+    }
+
+    if (this.lastDocument !== document) {
+      this.clearCache();
+
+      const mapPath = document.uri.fsPath + '.map';
+
+      try {
+        const sourceMapText = await fs.readFile(mapPath, 'utf-8');
+        const rawMap: RawSourceMap = JSON.parse(sourceMapText);
+        this.sourceMap = await new SourceMapConsumer(rawMap);
+      } catch (e: unknown) {
+        // Error reading sourcemap. Pretend there was no sourcemap.
+        void logger.log(`Error reading sourcemap file '${mapPath}': ${getErrorMessage(e)}`);
+        this.sourceMap = undefined;
+      }
+      this.lastDocument = document;
+    }
+
+    if (this.sourceMap === undefined) {
+      return undefined;
+    }
+
+    const qlPosition = this.sourceMap.originalPositionFor({
+      line: editor.selection.start.line + 1,
+      column: editor.selection.start.character,
+      bias: SourceMapConsumer.GREATEST_LOWER_BOUND
+    });
+
+    if ((qlPosition.source === null) || (qlPosition.line === null)) {
+      // No position found.
+      return undefined;
+    }
+    const line = qlPosition.line - 1;  // In `source-map`, lines are 1-based...
+    const column = qlPosition.column ?? 0;  // ...but columns are 0-based :(
+
+    return {
+      filePath: qlPosition.source,
+      position: new Position(line, column)
+    };
+  }
+
+  /**
+   * Clears the cached sourcemap and its corresponding `TextDocument`.
+   */
+  private clearCache(): void {
+    if (this.sourceMap !== undefined) {
+      this.sourceMap.destroy();
+      this.sourceMap = undefined;
+      this.lastDocument = undefined;
+    }
+  }
+
+  /**
+   * Updates the `codeql.hasQLSource` context variable based on the current selection. This variable
+   * controls whether or not the `codeQL.gotoQL` command is enabled.
+   */
+  private async updateContext(): Promise<void> {
+    const position = await this.getQLSourceLocation();
+
+    await commands.executeCommand('setContext', 'codeql.hasQLSource', position !== undefined);
+  }
+
+  handleDidChangeActiveTextEditor = async (_editor: TextEditor | undefined): Promise<void> => {
+    await this.updateContext();
+  }
+
+  handleDidChangeTextEditorSelection = async (_e: TextEditorSelectionChangeEvent): Promise<void> => {
+    await this.updateContext();
+  }
+
+  handleDidCloseTextDocument = (document: TextDocument): void => {
+    if (this.lastDocument === document) {
+      this.clearCache();
+    }
+  }
+
+  handleGotoQL = async (): Promise<void> => {
+    const position = await this.getQLSourceLocation();
+    if (position !== undefined) {
+      await showSourceLocation(position);
+    }
+  };
+}

extensions/ql-vscode/src/log-insights/summary-parser.ts

@@ -0,0 +1,113 @@
+import * as fs from 'fs-extra';
+
+/**
+ * Location information for a single pipeline invocation in the RA.
+ */
+export interface PipelineInfo {
+  startLine: number;
+  raStartLine: number;
+  raEndLine: number;
+}
+
+/**
+ * Location information for a single predicate in the RA.
+ */
+export interface PredicateSymbol {
+  /**
+   * `PipelineInfo` for each iteration. A non-recursive predicate will have a single iteration `0`.
+   */
+  iterations: Record<number, PipelineInfo>;
+}
+
+/**
+ * Location information for the RA from an evaluation log. Line numbers point into the
+ * human-readable log summary.
+ */
+export interface SummarySymbols {
+  predicates: Record<string, PredicateSymbol>;
+}
+
+// Tuple counts for Expr::Expr::getParent#dispred#f0820431#ff@76d6745o:
+const NON_RECURSIVE_TUPLE_COUNT_REGEXP = /^Evaluated relational algebra for predicate (?<predicateName>\S+) with tuple counts:$/;
+// Tuple counts for Expr::Expr::getEnclosingStmt#f0820431#bf@923ddwj9 on iteration 0 running pipeline base:
+const RECURSIVE_TUPLE_COUNT_REGEXP = /^Evaluated relational algebra for predicate (?<predicateName>\S+) on iteration (?<iteration>\d+) running pipeline (?<pipeline>\S+) with tuple counts:$/;
+const RETURN_REGEXP = /^\s*return /;
+
+/**
+ * Parse a human-readable evaluation log summary to find the location of the RA for each pipeline
+ * run.
+ *
+ * TODO: Once we're more certain about the symbol format, we should have the CLI generate this as it
+ * generates the human-readabe summary to avoid having to rely on regular expression matching of the
+ * human-readable text.
+ *
+ * @param summaryPath The path to the summary file.
+ * @param symbolsPath The path to the symbols file to generate.
+ */
+export async function generateSummarySymbolsFile(summaryPath: string, symbolsPath: string): Promise<void> {
+  const symbols = await generateSummarySymbols(summaryPath);
+  await fs.writeFile(symbolsPath, JSON.stringify(symbols));
+}
+
+/**
+ * Parse a human-readable evaluation log summary to find the location of the RA for each pipeline
+ * run.
+ *
+ * @param fileLocation The path to the summary file.
+ * @returns Symbol information for the summary file.
+ */
+async function generateSummarySymbols(summaryPath: string): Promise<SummarySymbols> {
+  const summary = await fs.promises.readFile(summaryPath, { encoding: 'utf-8' });
+  const symbols: SummarySymbols = {
+    predicates: {}
+  };
+
+  const lines = summary.split(/\r?\n/);
+  let lineNumber = 0;
+  while (lineNumber < lines.length) {
+    const startLineNumber = lineNumber;
+    lineNumber++;
+    const startLine = lines[startLineNumber];
+    const nonRecursiveMatch = startLine.match(NON_RECURSIVE_TUPLE_COUNT_REGEXP);
+    let predicateName: string | undefined = undefined;
+    let iteration = 0;
+    if (nonRecursiveMatch) {
+      predicateName = nonRecursiveMatch.groups!.predicateName;
+    } else {
+      const recursiveMatch = startLine.match(RECURSIVE_TUPLE_COUNT_REGEXP);
+      if (recursiveMatch?.groups) {
+        predicateName = recursiveMatch.groups.predicateName;
+        iteration = parseInt(recursiveMatch.groups.iteration);
+      }
+    }
+
+    if (predicateName !== undefined) {
+      const raStartLine = lineNumber;
+      let raEndLine: number | undefined = undefined;
+      while ((lineNumber < lines.length) && (raEndLine === undefined)) {
+        const raLine = lines[lineNumber];
+        const returnMatch = raLine.match(RETURN_REGEXP);
+        if (returnMatch) {
+          raEndLine = lineNumber;
+        }
+        lineNumber++;
+      }
+      if (raEndLine !== undefined) {
+        let symbol = symbols.predicates[predicateName];
+        if (symbol === undefined) {
+          symbol = {
+            iterations: {}
+          };
+          symbols.predicates[predicateName] = symbol;
+        }
+        symbol.iterations[iteration] = {
+          startLine: lineNumber,
+          raStartLine: raStartLine,
+          raEndLine: raEndLine
+        };
+      }
+    }
+  }
+
+  return symbols;
+}

extensions/ql-vscode/src/logging.ts

@@ -1,5 +1,5 @@
-import { window as Window, OutputChannel, Progress, Disposable } from 'vscode';
-import { DisposableObject } from './vscode-utils/disposable-object';
+import { window as Window, OutputChannel, Progress } from 'vscode';
+import { DisposableObject } from './pure/disposable-object';
 import * as fs from 'fs-extra';
 import * as path from 'path';
 
@@ -26,11 +26,6 @@ export interface Logger {
    * @param location log to remove
    */
   removeAdditionalLogLocation(location: string | undefined): void;
-
-  /**
-   * The base location location where all side log files are stored.
-   */
-  getBaseLocation(): string | undefined;
 }
 
 export type ProgressReporter = Progress<{ message: string }>;
@@ -39,19 +34,13 @@ export type ProgressReporter = Progress<{ message: string }>;
 export class OutputChannelLogger extends DisposableObject implements Logger {
   public readonly outputChannel: OutputChannel;
   private readonly additionalLocations = new Map<string, AdditionalLogLocation>();
-  private additionalLogLocationPath: string | undefined;
+  isCustomLogDirectory: boolean;
 
-  constructor(private title: string) {
+  constructor(title: string) {
     super();
     this.outputChannel = Window.createOutputChannel(title);
     this.push(this.outputChannel);
-  }
-
-  init(storagePath: string): void {
-    this.additionalLogLocationPath = path.join(storagePath, this.title);
-
-    // clear out any old state from previous runs
-    fs.remove(this.additionalLogLocationPath);
+    this.isCustomLogDirectory = false;
   }
 
   /**
@@ -61,31 +50,41 @@ export class OutputChannelLogger extends DisposableObject implements Logger {
    * continuing.
    */
   async log(message: string, options = {} as LogOptions): Promise<void> {
-    if (options.trailingNewline === undefined) {
-      options.trailingNewline = true;
-    }
-
-    if (options.trailingNewline) {
-      this.outputChannel.appendLine(message);
-    } else {
-      this.outputChannel.append(message);
-    }
-
-    if (this.additionalLogLocationPath && options.additionalLogLocation) {
-      const logPath = path.join(this.additionalLogLocationPath, options.additionalLogLocation);
-      let additional = this.additionalLocations.get(logPath);
-      if (!additional) {
-        const msg = `| Log being saved to ${logPath} |`;
-        const separator = new Array(msg.length).fill('-').join('');
-        this.outputChannel.appendLine(separator);
-        this.outputChannel.appendLine(msg);
-        this.outputChannel.appendLine(separator);
-        additional = new AdditionalLogLocation(logPath);
-        this.additionalLocations.set(logPath, additional);
-        this.track(additional);
+    try {
+      if (options.trailingNewline === undefined) {
+        options.trailingNewline = true;
+      }
+      if (options.trailingNewline) {
+        this.outputChannel.appendLine(message);
+      } else {
+        this.outputChannel.append(message);
       }
 
-      await additional.log(message, options);
+      if (options.additionalLogLocation) {
+        if (!path.isAbsolute(options.additionalLogLocation)) {
+          throw new Error(`Additional Log Location must be an absolute path: ${options.additionalLogLocation}`);
+        }
+        const logPath = options.additionalLogLocation;
+        let additional = this.additionalLocations.get(logPath);
+        if (!additional) {
+          const msg = `| Log being saved to ${logPath} |`;
+          const separator = new Array(msg.length).fill('-').join('');
+          this.outputChannel.appendLine(separator);
+          this.outputChannel.appendLine(msg);
+          this.outputChannel.appendLine(separator);
+          additional = new AdditionalLogLocation(logPath);
+          this.additionalLocations.set(logPath, additional);
+        }
+
+        await additional.log(message, options);
+      }
+    } catch (e) {
+      if (e instanceof Error && e.message === 'Channel has been closed') {
+        // Output channel is closed logging to console instead
+        console.log('Output channel is closed logging to console instead:', message);
+      } else {
+        throw e;
+      }
     }
   }
 
@@ -94,26 +93,15 @@ export class OutputChannelLogger extends DisposableObject implements Logger {
   }
 
   removeAdditionalLogLocation(location: string | undefined): void {
-    if (this.additionalLogLocationPath && location) {
-      const logPath = location.startsWith(this.additionalLogLocationPath)
-        ? location
-        : path.join(this.additionalLogLocationPath, location);
-      const additional = this.additionalLocations.get(logPath);
-      if (additional) {
-        this.disposeAndStopTracking(additional);
-        this.additionalLocations.delete(logPath);
-      }
+    if (location) {
+      this.additionalLocations.delete(location);
     }
   }
-
-  getBaseLocation() {
-    return this.additionalLogLocationPath;
-  }
 }
 
-class AdditionalLogLocation extends Disposable {
+class AdditionalLogLocation {
   constructor(private location: string) {
-    super(() => { /**/ });
+    /**/
   }
 
   async log(message: string, options = {} as LogOptions): Promise<void> {
@@ -126,10 +114,6 @@ class AdditionalLogLocation extends Disposable {
       encoding: 'utf8'
     });
   }
-
-  async dispose(): Promise<void> {
-    await fs.remove(this.location);
-  }
 }
 
 /** The global logger for the extension. */

extensions/ql-vscode/src/packaging.ts

@@ -0,0 +1,146 @@
+import { CliVersionConstraint, CodeQLCliServer } from './cli';
+import {
+  getOnDiskWorkspaceFolders,
+  showAndLogErrorMessage,
+  showAndLogInformationMessage,
+} from './helpers';
+import { QuickPickItem, window } from 'vscode';
+import { ProgressCallback, UserCancellationException } from './commandRunner';
+import { logger } from './logging';
+
+const QUERY_PACKS = [
+  'codeql/cpp-queries',
+  'codeql/csharp-queries',
+  'codeql/go-queries',
+  'codeql/java-queries',
+  'codeql/javascript-queries',
+  'codeql/python-queries',
+  'codeql/ruby-queries',
+  'codeql/csharp-solorigate-queries',
+  'codeql/javascript-experimental-atm-queries',
+];
+
+/**
+ * Prompts user to choose packs to download, and downloads them.
+ *
+ * @param cliServer The CLI server.
+ * @param progress A progress callback.
+ */
+export async function handleDownloadPacks(
+  cliServer: CodeQLCliServer,
+  progress: ProgressCallback,
+): Promise<void> {
+  if (!(await cliServer.cliConstraints.supportsPackaging())) {
+    throw new Error(`Packaging commands are not supported by this version of CodeQL. Please upgrade to v${CliVersionConstraint.CLI_VERSION_WITH_PACKAGING
+      } or later.`);
+  }
+  progress({
+    message: 'Choose packs to download',
+    step: 1,
+    maxStep: 2,
+  });
+  let packsToDownload: string[] = [];
+  const queryPackOption = 'Download all core query packs';
+  const customPackOption = 'Download custom specified pack';
+  const quickpick = await window.showQuickPick(
+    [queryPackOption, customPackOption],
+    { ignoreFocusOut: true }
+  );
+  if (quickpick === queryPackOption) {
+    packsToDownload = QUERY_PACKS;
+  } else if (quickpick === customPackOption) {
+    const customPack = await window.showInputBox({
+      prompt:
+        'Enter the <package-scope/name[@version]> of the pack to download',
+      ignoreFocusOut: true,
+    });
+    if (customPack) {
+      packsToDownload.push(customPack);
+    } else {
+      throw new UserCancellationException('No pack specified.');
+    }
+  }
+  if (packsToDownload?.length > 0) {
+    progress({
+      message: 'Downloading packs. This may take a few minutes.',
+      step: 2,
+      maxStep: 2,
+    });
+    try {
+      await cliServer.packDownload(packsToDownload);
+      void showAndLogInformationMessage('Finished downloading packs.');
+    } catch (error) {
+      void showAndLogErrorMessage(
+        'Unable to download all packs. See log for more details.'
+      );
+    }
+  }
+}
+
+interface QLPackQuickPickItem extends QuickPickItem {
+  packRootDir: string[];
+}
+
+/**
+ * Prompts user to choose packs to install, and installs them.
+ *
+ * @param cliServer The CLI server.
+ * @param progress A progress callback.
+ */
+export async function handleInstallPackDependencies(
+  cliServer: CodeQLCliServer,
+  progress: ProgressCallback,
+): Promise<void> {
+  if (!(await cliServer.cliConstraints.supportsPackaging())) {
+    throw new Error(`Packaging commands are not supported by this version of CodeQL. Please upgrade to v${CliVersionConstraint.CLI_VERSION_WITH_PACKAGING
+      } or later.`);
+  }
+  progress({
+    message: 'Choose packs to install dependencies for',
+    step: 1,
+    maxStep: 2,
+  });
+  const workspacePacks = await cliServer.resolveQlpacks(getOnDiskWorkspaceFolders());
+  const quickPickItems = Object.entries(workspacePacks).map<QLPackQuickPickItem>(([key, value]) => ({
+    label: key,
+    packRootDir: value,
+  }));
+  const packsToInstall = await window.showQuickPick(quickPickItems, {
+    placeHolder: 'Select packs to install dependencies for',
+    canPickMany: true,
+    ignoreFocusOut: true,
+  });
+  const numberOfPacks = packsToInstall?.length || 0;
+  if (packsToInstall && numberOfPacks > 0) {
+    const failedPacks = [];
+    const errors = [];
+    // Start at 1 because we already have the first step
+    let count = 1;
+    for (const pack of packsToInstall) {
+      count++;
+      progress({
+        message: `Installing dependencies for ${pack.label}`,
+        step: count,
+        maxStep: numberOfPacks + 1,
+      });
+      try {
+        for (const dir of pack.packRootDir) {
+          await cliServer.packInstall(dir);
+        }
+      } catch (error) {
+        failedPacks.push(pack.label);
+        errors.push(error);
+      }
+    }
+    if (failedPacks.length > 0) {
+      void logger.log(`Errors:\n${errors.join('\n')}`);
+      throw new Error(
+        `Unable to install pack dependencies for: ${failedPacks.join(', ')}. See log for more details.`
+      );
+    } else {
+      void showAndLogInformationMessage('Finished installing pack dependencies.');
+    }
+  } else {
+    throw new UserCancellationException('No packs selected.');
+  }
+}

extensions/ql-vscode/src/pure/bqrs-cli-types.ts

@@ -79,11 +79,11 @@ export interface WholeFileLocation {
 
 export type ResolvableLocationValue = WholeFileLocation | LineColumnLocation;
 
-export type UrlValue = ResolvableLocationValue  | string;
+export type UrlValue = ResolvableLocationValue | string;
 
-export type ColumnValue = EntityValue | number | string | boolean;
+export type CellValue = EntityValue | number | string | boolean;
 
-export type ResultRow = ColumnValue[];
+export type ResultRow = CellValue[];
 
 export interface RawResultSet {
   readonly schema: ResultSetSchema;
@@ -103,7 +103,14 @@ export function transformBqrsResultSet(
   };
 }
 
-export interface DecodedBqrsChunk {
-  tuples: ColumnValue[][];
-  next?: number;
+type BqrsKind = 'String' | 'Float' | 'Integer' | 'String' | 'Boolean' | 'Date' | 'Entity';
+
+interface BqrsColumn {
+  name: string;
+  kind: BqrsKind;
+}
+export interface DecodedBqrsChunk {
+  tuples: CellValue[][];
+  next?: number;
+  columns: BqrsColumn[];
 }

extensions/ql-vscode/src/pure/bqrs-utils.ts

@@ -4,6 +4,7 @@ import {
   LineColumnLocation,
   WholeFileLocation
 } from './bqrs-cli-types';
+import { createRemoteFileRef } from './location-link-utils';
 
 /**
  * The CodeQL filesystem libraries use this pattern in `getURL()` predicates
@@ -83,8 +84,7 @@ export function isLineColumnLoc(loc: UrlValue): loc is LineColumnLocation {
     && 'startLine' in loc
     && 'startColumn' in loc
     && 'endLine' in loc
-    && 'endColumn' in loc
-    && loc.endColumn > 0;
+    && 'endColumn' in loc;
 }
 
 export function isWholeFileLoc(loc: UrlValue): loc is WholeFileLocation {
@@ -94,3 +94,45 @@ export function isWholeFileLoc(loc: UrlValue): loc is WholeFileLocation {
 export function isStringLoc(loc: UrlValue): loc is string {
   return typeof loc === 'string';
 }
+
+export function tryGetRemoteLocation(
+  loc: UrlValue | undefined,
+  fileLinkPrefix: string,
+  sourceLocationPrefix: string | undefined,
+): string | undefined {
+  const resolvableLocation = tryGetResolvableLocation(loc);
+  if (!resolvableLocation) {
+    return undefined;
+  }
+
+  let trimmedLocation: string;
+
+  // Remote locations have the following format:
+  // "file:${sourceLocationPrefix}/relative/path/to/file"
+  // So we need to strip off the first part to get the relative path.
+  if (sourceLocationPrefix) {
+    if (!resolvableLocation.uri.startsWith(`file:${sourceLocationPrefix}/`)) {
+      return undefined;
+    }
+    trimmedLocation = resolvableLocation.uri.replace(`file:${sourceLocationPrefix}/`, '');
+  } else {
+    // If the source location prefix is empty (e.g. for older remote queries), we assume that the database
+    // was created on a Linux actions runner and has the format:
+    // "file:/home/runner/work/<repo>/<repo>/relative/path/to/file"
+    // So we need to drop the first 6 parts of the path.
+    if (!resolvableLocation.uri.startsWith('file:/home/runner/work/')) {
+      return undefined;
+    }
+    const locationParts = resolvableLocation.uri.split('/');
+    trimmedLocation = locationParts.slice(6, locationParts.length).join('/');
+  }
+
+  const fileLink = {
+    fileLinkPrefix,
+    filePath: trimmedLocation,
+  };
+  return createRemoteFileRef(
+    fileLink,
+    resolvableLocation.startLine,
+    resolvableLocation.endLine);
+}

extensions/ql-vscode/src/pure/date.ts

@@ -0,0 +1,39 @@
+/*
+ * Contains an assortment of helper constants and functions for working with dates.
+ */
+
+const dateWithoutYearFormatter = new Intl.DateTimeFormat(undefined, {
+  month: 'short',
+  day: 'numeric',
+  hour: 'numeric',
+  minute: '2-digit',
+});
+
+const dateFormatter = new Intl.DateTimeFormat(undefined, {
+  year: 'numeric',
+  month: 'short',
+  day: 'numeric',
+  hour: 'numeric',
+  minute: '2-digit',
+});
+
+export function formatDate(value: Date): string {
+  if (value.getFullYear() === new Date().getFullYear()) {
+    return dateWithoutYearFormatter.format(value);
+  }
+
+  return dateFormatter.format(value);
+}
+
+// These are overloads for the function that allow us to not add an extra
+// type check when the value is definitely not undefined.
+export function parseDate(value: string): Date;
+export function parseDate(value: string | undefined | null): Date | undefined;
+
+export function parseDate(value: string | undefined | null): Date | undefined {
+  if (value === undefined || value === null) {
+    return undefined;
+  }
+
+  return new Date(value);
+}

extensions/ql-vscode/src/pure/disposable-object.ts

@@ -1,4 +1,11 @@
-import { Disposable } from 'vscode';
+
+// Avoid explicitly referencing Disposable type in vscode.
+// This file cannot have dependencies on the vscode API.
+interface Disposable {
+  dispose(): any;
+}
+
+export type DisposeHandler = (disposable: Disposable) => void;
 
 /**
  * Base class to make it easier to implement a `Disposable` that owns other disposable object.
@@ -40,21 +47,39 @@ export abstract class DisposableObject implements Disposable {
    * @param obj The object to stop tracking.
    */
   protected disposeAndStopTracking(obj: Disposable): void {
-    if (obj !== undefined) {
-      this.tracked!.delete(obj);
+    if (obj && this.tracked) {
+      this.tracked.delete(obj);
       obj.dispose();
     }
   }
 
-  public dispose() {
+  /**
+   * Dispose this object and all contained objects
+   *
+   * @param disposeHandler An optional dispose handler that gets
+   *      passed each element to dispose. The dispose handler
+   *      can choose how (and if) to dispose the object. The
+   *      primary usage is for tests that should not dispose
+   *      all items of a disposable.
+   */
+  public dispose(disposeHandler?: DisposeHandler) {
     if (this.tracked !== undefined) {
       for (const trackedObject of this.tracked.values()) {
-        trackedObject.dispose();
+        if (disposeHandler) {
+          disposeHandler(trackedObject);
+        } else {
+          trackedObject.dispose();
+        }
       }
       this.tracked = undefined;
     }
     while (this.disposables.length > 0) {
-      this.disposables.pop()!.dispose();
+      const disposable = this.disposables.pop()!;
+      if (disposeHandler) {
+        disposeHandler(disposable);
+      } else {
+        disposable.dispose();
+      }
     }
   }
 }

extensions/ql-vscode/src/pure/helpers-pure.ts

@@ -1,8 +1,9 @@
+
 /**
  * helpers-pure.ts
  * ------------
  *
- * Helper functions that don't depend on vscode and therefore can be used by the front-end and pure unit tests.
+ * Helper functions that don't depend on vscode or the CLI and therefore can be used by the front-end and pure unit tests.
  */
 
 /**
@@ -29,3 +30,28 @@ export const asyncFilter = async function <T>(arr: T[], predicate: (arg0: T) =>
   const results = await Promise.all(arr.map(predicate));
   return arr.filter((_, index) => results[index]);
 };
+
+/**
+ * This regex matches strings of the form `owner/repo` where:
+ * - `owner` is made up of alphanumeric characters, hyphens, underscores, or periods
+ * - `repo` is made up of alphanumeric characters, hyphens, underscores, or periods
+ */
+export const REPO_REGEX = /^[a-zA-Z0-9-_\.]+\/[a-zA-Z0-9-_\.]+$/;
+
+/**
+ * This regex matches GiHub organization and user strings. These are made up for alphanumeric 
+ * characters, hyphens, underscores or periods.
+ */
+export const OWNER_REGEX = /^[a-zA-Z0-9-_\.]+$/;
+
+export function getErrorMessage(e: any) {
+  return e instanceof Error ? e.message : String(e);
+}
+
+export function getErrorStack(e: any) {
+  return e instanceof Error ? e.stack ?? '' : '';
+}
+
+export function asError(e: any): Error {
+  return e instanceof Error ? e : new Error(String(e));
+}

extensions/ql-vscode/src/pure/interface-types.ts

@@ -1,5 +1,12 @@
 import * as sarif from 'sarif';
+import { AnalysisResults } from '../remote-queries/shared/analysis-result';
+import { AnalysisSummary, RemoteQueryResult } from '../remote-queries/shared/remote-query-result';
 import { RawResultSet, ResultRow, ResultSetSchema, Column, ResolvableLocationValue } from './bqrs-cli-types';
+import {
+  VariantAnalysis,
+  VariantAnalysisScannedRepositoryResult,
+  VariantAnalysisScannedRepositoryState,
+} from '../remote-queries/shared/variant-analysis';
 
 /**
  * This module contains types and code that are shared between
@@ -8,15 +15,17 @@ import { RawResultSet, ResultRow, ResultSetSchema, Column, ResolvableLocationVal
 
 export const SELECT_TABLE_NAME = '#select';
 export const ALERTS_TABLE_NAME = 'alerts';
+export const GRAPH_TABLE_NAME = 'graph';
 
 export type RawTableResultSet = { t: 'RawResultSet' } & RawResultSet;
-export type PathTableResultSet = {
-  t: 'SarifResultSet';
+export type InterpretedResultSet<T> = {
+  t: 'InterpretedResultSet';
   readonly schema: ResultSetSchema;
   name: string;
-} & Interpretation;
+  interpretation: InterpretationT<T>;
+};
 
-export type ResultSet = RawTableResultSet | PathTableResultSet;
+export type ResultSet = RawTableResultSet | InterpretedResultSet<InterpretationData>;
 
 /**
  * Only ever show this many rows in a raw result table.
@@ -34,6 +43,7 @@ export interface QueryMetadata {
   description?: string;
   id?: string;
   kind?: string;
+  scored?: string;
 }
 
 export interface PreviousExecution {
@@ -43,18 +53,31 @@ export interface PreviousExecution {
   durationSeconds: number;
 }
 
-export interface Interpretation {
-  sourceLocationPrefix: string;
-  numTruncatedResults: number;
-  numTotalResults: number;
+export type SarifInterpretationData = {
+  t: 'SarifInterpretationData';
   /**
    * sortState being undefined means don't sort, just present results in the order
    * they appear in the sarif file.
    */
   sortState?: InterpretedResultsSortState;
-  sarif: sarif.Log;
+} & sarif.Log;
+
+export type GraphInterpretationData = {
+  t: 'GraphInterpretationData';
+  dot: string[];
+};
+
+export type InterpretationData = SarifInterpretationData | GraphInterpretationData;
+
+export interface InterpretationT<T> {
+  sourceLocationPrefix: string;
+  numTruncatedResults: number;
+  numTotalResults: number;
+  data: T;
 }
 
+export type Interpretation = InterpretationT<InterpretationData>;
+
 export interface ResultsPaths {
   resultsPath: string;
   interpretedResultsPath: string;
@@ -88,6 +111,8 @@ export interface SetStateMsg {
   interpretation: undefined | Interpretation;
   database: DatabaseInfo;
   metadata?: QueryMetadata;
+  queryName: string;
+  queryPath: string;
   /**
    * Whether to keep displaying the old results while rendering the new results.
    *
@@ -116,6 +141,8 @@ export interface ShowInterpretedPageMsg {
   numPages: number;
   pageSize: number;
   resultSetNames: string[];
+  queryName: string;
+  queryPath: string;
 }
 
 /** Advance to the next or previous path no in the path viewer */
@@ -152,8 +179,9 @@ export type FromResultsViewMsg =
   | ToggleDiagnostics
   | ChangeRawResultsSortMsg
   | ChangeInterpretedResultsSortMsg
-  | ResultViewLoaded
-  | ChangePage;
+  | ViewLoadedMsg
+  | ChangePage
+  | OpenFileMsg;
 
 /**
  * Message from the results view to open a database source
@@ -165,6 +193,19 @@ export interface ViewSourceFileMsg {
   databaseUri: string;
 }
 
+/**
+ * Message from the results view to open a file in an editor.
+ */
+export interface OpenFileMsg {
+  t: 'openFile';
+  /* Full path to the file to open. */
+  filePath: string;
+}
+
+export interface OpenVirtualFileMsg {
+  t: 'openVirtualFile';
+  queryText: string;
+}
 
 /**
  * Message from the results view to toggle the display of
@@ -180,11 +221,11 @@ interface ToggleDiagnostics {
 }
 
 /**
- * Message from the results view to signal that loading the results
- * is complete.
+ * Message from a view signal that loading is complete.
  */
-interface ResultViewLoaded {
-  t: 'resultViewLoaded';
+interface ViewLoadedMsg {
+  t: 'viewLoaded';
+  viewName: string;
 }
 
 /**
@@ -243,18 +284,11 @@ interface ChangeInterpretedResultsSortMsg {
  * Message from the compare view to the extension.
  */
 export type FromCompareViewMessage =
-  | CompareViewLoadedMessage
+  | ViewLoadedMsg
   | ChangeCompareMessage
   | ViewSourceFileMsg
   | OpenQueryMessage;
 
-/**
- * Message from the compare view to signal the completion of loading results.
- */
-interface CompareViewLoadedMessage {
-  t: 'compareViewLoaded';
-}
-
 /**
  * Message from the compare view to request opening a query.
  */
@@ -295,7 +329,7 @@ export interface SetComparisonsMessage {
   readonly currentResultSetName: string;
   readonly rows: QueryCompareResult | undefined;
   readonly message: string | undefined;
-  readonly datebaseUri: string;
+  readonly databaseUri: string;
 }
 
 export enum DiffKind {
@@ -336,8 +370,9 @@ export function getDefaultResultSetName(
   // Choose first available result set from the array
   return [
     ALERTS_TABLE_NAME,
+    GRAPH_TABLE_NAME,
     SELECT_TABLE_NAME,
-    resultSetNames[0],
+    resultSetNames[0]
   ].filter((resultSetName) => resultSetNames.includes(resultSetName))[0];
 }
 
@@ -350,3 +385,101 @@ export interface ParsedResultSets {
   resultSetNames: string[];
   resultSet: ResultSet;
 }
+
+export type FromRemoteQueriesMessage =
+  | ViewLoadedMsg
+  | RemoteQueryErrorMessage
+  | OpenFileMsg
+  | OpenVirtualFileMsg
+  | RemoteQueryDownloadAnalysisResultsMessage
+  | RemoteQueryDownloadAllAnalysesResultsMessage
+  | RemoteQueryExportResultsMessage
+  | CopyRepoListMessage;
+
+export type ToRemoteQueriesMessage =
+  | SetRemoteQueryResultMessage
+  | SetAnalysesResultsMessage;
+
+export interface SetRemoteQueryResultMessage {
+  t: 'setRemoteQueryResult';
+  queryResult: RemoteQueryResult
+}
+
+export interface SetAnalysesResultsMessage {
+  t: 'setAnalysesResults';
+  analysesResults: AnalysisResults[];
+}
+
+export interface RemoteQueryErrorMessage {
+  t: 'remoteQueryError';
+  error: string;
+}
+
+export interface RemoteQueryDownloadAnalysisResultsMessage {
+  t: 'remoteQueryDownloadAnalysisResults';
+  analysisSummary: AnalysisSummary
+}
+
+export interface RemoteQueryDownloadAllAnalysesResultsMessage {
+  t: 'remoteQueryDownloadAllAnalysesResults';
+  analysisSummaries: AnalysisSummary[];
+}
+
+export interface RemoteQueryExportResultsMessage {
+  t: 'remoteQueryExportResults';
+  queryId: string;
+}
+
+export interface CopyRepoListMessage {
+  t: 'copyRepoList';
+  queryId: string;
+}
+
+export interface SetVariantAnalysisMessage {
+  t: 'setVariantAnalysis';
+  variantAnalysis: VariantAnalysis;
+}
+
+export type StopVariantAnalysisMessage = {
+  t: 'stopVariantAnalysis';
+  variantAnalysisId: number;
+}
+
+export type VariantAnalysisState = {
+  variantAnalysisId: number;
+}
+
+export interface SetRepoResultsMessage {
+  t: 'setRepoResults';
+  repoResults: VariantAnalysisScannedRepositoryResult[];
+}
+
+export interface SetRepoStatesMessage {
+  t: 'setRepoStates';
+  repoStates: VariantAnalysisScannedRepositoryState[];
+}
+
+export interface RequestRepositoryResultsMessage {
+  t: 'requestRepositoryResults';
+  repositoryFullName: string;
+}
+
+export interface OpenQueryFileMessage {
+  t: 'openQueryFile';
+}
+
+export interface OpenQueryTextMessage {
+  t: 'openQueryText';
+}
+
+export type ToVariantAnalysisMessage =
+  | SetVariantAnalysisMessage
+  | SetRepoResultsMessage
+  | SetRepoStatesMessage;
+
+export type FromVariantAnalysisMessage =
+  | ViewLoadedMsg
+  | StopVariantAnalysisMessage
+  | RequestRepositoryResultsMessage
+  | OpenQueryFileMessage
+  | OpenQueryTextMessage;

extensions/ql-vscode/src/pure/legacy-messages.ts

@@ -15,38 +15,7 @@
  */
 
 import * as rpc from 'vscode-jsonrpc';
-
-/**
- * A position within a QL file.
- */
-export interface Position {
-  /**
-   * The one-based index of the start line
-   */
-  line: number;
-  /**
-   * The one-based offset of the start column within
-   * the start line in UTF-16 code-units
-   */
-  column: number;
-  /**
-   * The one-based index of the end line line
-   */
-  endLine: number;
-
-  /**
-   * The one-based offset of the end column within
-   * the end line in UTF-16 code-units
-   */
-  endColumn: number;
-  /**
-   * The path of the file.
-   * If the file name is "Compiler Generated" the
-   * the position is not a real position but
-   * arises from compiler generated code.
-   */
-  fileName: string;
-}
+import * as shared from './messages-shared';
 
 /**
  * A query that should be checked for any errors or warnings
@@ -150,6 +119,15 @@ export interface CompilationOptions {
    * Whether to disable toString values in the results.
    */
   noComputeToString: boolean;
+  /**
+   * Whether to ensure that elements that do not have a displayString
+   * get reported anyway. Useful for universal compilation options.
+   */
+  computeDefaultStrings: boolean;
+  /**
+   * Emit debug information in compiled query.
+   */
+  emitDebugInfo: boolean;
 }
 
 /**
@@ -249,28 +227,6 @@ export interface DILQuery {
   dilSource: string;
 }
 
-/**
- * The way of compiling the query, as a normal query
- * or a subset of it. Note that precisely one of the two options should be set.
- */
-export interface CompilationTarget {
-  /**
-   * Compile as a normal query
-   */
-  query?: {};
-  /**
-   * Compile as a quick evaluation
-   */
-  quickEval?: QuickEvalOptions;
-}
-
-/**
- * Options for quick evaluation
- */
-export interface QuickEvalOptions {
-  quickEvalPos?: Position;
-}
-
 /**
  * The result of checking a query.
  */
@@ -380,8 +336,8 @@ export namespace ResultColumnKind {
    */
   export const BOOLEAN = 3;
   /**
- * A column of type `date`
- */
+   * A column of type `date`
+   */
   export const DATE = 4;
   /**
    * A column of a non-primitive type
@@ -401,6 +357,25 @@ export interface CompileUpgradeParams {
    * A directory to store parts of the compiled upgrade
    */
   upgradeTempDir: string;
+  /**
+   * Enable single file upgrades, set to true to allow
+   * using single file upgrades.
+   */
+  singleFileUpgrades: true;
+}
+
+/**
+ * Parameters for compiling an upgrade.
+ */
+export interface CompileUpgradeSequenceParams {
+  /**
+   * The sequence of upgrades to compile
+   */
+  upgradePaths: string[];
+  /**
+   * A directory to store parts of the compiled upgrade
+   */
+  upgradeTempDir: string;
 }
 
 /**
@@ -450,6 +425,19 @@ export interface CompileUpgradeResult {
    */
   error?: string;
 }
+
+export interface CompileUpgradeSequenceResult {
+  /**
+   * The compiled upgrades as a single file.
+   */
+  compiledUpgrade?: string;
+  /**
+   * Any errors that occurred when checking the scripts.
+   */
+  error?: string;
+}
+
+
 /**
  * A description of a upgrade process
  */
@@ -487,10 +475,13 @@ export interface UpgradeDescription {
   newSha: string;
 }
 
+
+export type CompiledUpgrades = MultiFileCompiledUpgrades | SingleFileCompiledUpgrades
+
 /**
- * A compiled upgrade.
+ * The parts shared by all compiled upgrades
  */
-export interface CompiledUpgrades {
+interface CompiledUpgradesBase {
   /**
   * The initial sha of the dbscheme to upgrade from
   */
@@ -499,14 +490,46 @@ export interface CompiledUpgrades {
    * The path to the new dataset statistics
    */
   newStatsPath: string;
+  /**
+   * The sha of the target dataset.
+   */
+  targetSha: string;
+}
+
+
+/**
+ * A compiled upgrade.
+ * The upgrade is spread among multiple files.
+ */
+interface MultiFileCompiledUpgrades extends CompiledUpgradesBase {
+  /**
+   * The path to the new dataset dbscheme
+   */
+  newDbscheme: string;
   /**
    * The steps in the upgrade path
    */
   scripts: CompiledUpgradeScript[];
   /**
-   * The sha of the target dataset.
+   * Will never exist in an old result
    */
-  targetSha: string;
+  compiledUpgradeFile?: never;
+}
+
+
+/**
+ * A compiled upgrade.
+ * The upgrade is in a single file.
+ */
+export interface SingleFileCompiledUpgrades extends CompiledUpgradesBase {
+  /**
+   * The steps in the upgrade path
+   */
+  descriptions: UpgradeDescription[];
+  /**
+   * A path to a file containing the upgrade
+   */
+  compiledUpgradeFile: string;
 }
 
 /**
@@ -574,6 +597,35 @@ export interface ClearCacheParams {
    */
   dryRun: boolean;
 }
+
+/**
+ * Parameters to start a new structured log
+ */
+export interface StartLogParams {
+  /**
+   * The dataset for which we want to start a new structured log
+   */
+  db: Dataset;
+  /**
+   * The path where we want to place the new structured log
+   */
+  logPath: string;
+}
+
+/**
+ * Parameters to terminate a structured log
+ */
+export interface EndLogParams {
+  /**
+   * The dataset for which we want to terminated the log
+   */
+  db: Dataset;
+  /**
+   * The path of the log to terminate, will be a no-op if we aren't logging here
+   */
+  logPath: string;
+}
+
 /**
  * Parameters for trimming the cache of a dataset
  */
@@ -610,6 +662,26 @@ export interface ClearCacheResult {
   deletionMessage: string;
 }
 
+/**
+ * The result of starting a new structured log.
+ */
+export interface StartLogResult {
+  /**
+   * A user friendly message saying what happened.
+   */
+  outcomeMessage: string;
+}
+
+/**
+ * The result of terminating a structured log.
+ */
+export interface EndLogResult {
+  /**
+   * A user friendly message saying what happened.
+   */
+  outcomeMessage: string;
+}
+
 /**
  * Parameters for running a set of queries
  */
@@ -639,6 +711,11 @@ export interface EvaluateQueriesParams {
 
 export type TemplateDefinitions = { [key: string]: TemplateSource }
 
+export interface MlModel {
+  /** A URI pointing to the root directory of the model. */
+  uri: string;
+}
+
 /**
  * A single query that should be run
  */
@@ -651,6 +728,10 @@ export interface QueryToRun {
    * A uri pointing to the qlo to run.
    */
   qlo: string;
+  /**
+   * A uri pointing to the compiled upgrade file.
+   */
+  compiledUpgrade?: string;
   /**
    * The path where we should save this queries results
    */
@@ -668,6 +749,11 @@ export interface QueryToRun {
    * map should be set to the empty set or give an error.
    */
   allowUnknownTemplates: boolean;
+  /**
+   * The list of ML models that should be made available
+   * when evaluating the query.
+   */
+  availableMlModels?: MlModel[];
 }
 
 /**
@@ -750,7 +836,7 @@ export interface ResultSet {
 /**
  * The type returned when the evaluation is complete
  */
-export type EvaluationComplete = {};
+export type EvaluationComplete = Record<string, never>;
 
 /**
  * The result of a single query
@@ -837,7 +923,6 @@ export interface RunUpgradeParams {
   toRun: CompiledUpgrades;
 }
 
-
 /**
  * The result of running an upgrade
  */
@@ -857,39 +942,37 @@ export interface RunUpgradeResult {
   finalSha: string;
 }
 
+export interface RegisterDatabasesParams {
+  databases: Dataset[];
+}
+
+export interface DeregisterDatabasesParams {
+  databases: Dataset[];
+}
+
+export type RegisterDatabasesResult = {
+  registeredDatabases: Dataset[];
+};
+
+export type DeregisterDatabasesResult = {
+  registeredDatabases: Dataset[];
+};
 
 /**
- * Type for any action that could have progress messages.
+ * A position within a QL file.
  */
-export interface WithProgressId<T> {
-  /**
-   * The main body
-   */
-  body: T;
-  /**
-   * The id used to report progress updates
-   */
-  progressId: number;
-}
+export type Position = shared.Position;
 
-export interface ProgressMessage {
-  /**
-   * The id of the operation that is running
-   */
-  id: number;
-  /**
-   * The current step
-   */
-  step: number;
-  /**
-   * The maximum step. This *should* be constant for a single job.
-   */
-  maxStep: number;
-  /**
-   * The current progress message
-   */
-  message: string;
-}
+/**
+ * The way of compiling the query, as a normal query
+ * or a subset of it. Note that precisely one of the two options should be set.
+ */
+export type CompilationTarget = shared.CompilationTarget;
+
+export type QuickEvalOptions = shared.QuickEvalOptions;
+
+export type WithProgressId<T> = shared.WithProgressId<T>;
+export type ProgressMessage = shared.ProgressMessage;
 
 /**
  * Check a Ql query for errors without compiling it
@@ -913,7 +996,20 @@ export const checkUpgrade = new rpc.RequestType<WithProgressId<UpgradeParams>, C
  * Compile an upgrade script to upgrade a dataset.
  */
 export const compileUpgrade = new rpc.RequestType<WithProgressId<CompileUpgradeParams>, CompileUpgradeResult, void, void>('compilation/compileUpgrade');
+/**
+ * Compile an upgrade script to upgrade a dataset.
+ */
+export const compileUpgradeSequence = new rpc.RequestType<WithProgressId<CompileUpgradeSequenceParams>, CompileUpgradeSequenceResult, void, void>('compilation/compileUpgradeSequence');
 
+/**
+ * Start a new structured log in the evaluator, terminating the previous one if it exists
+ */
+export const startLog = new rpc.RequestType<WithProgressId<StartLogParams>, StartLogResult, void, void>('evaluation/startLog');
+
+/**
+ * Terminate a structured log in the evaluator. Is a no-op if we aren't logging to the given location
+ */
+export const endLog = new rpc.RequestType<WithProgressId<EndLogParams>, EndLogResult, void, void>('evaluation/endLog');
 
 /**
  * Clear the cache of a dataset
@@ -934,13 +1030,24 @@ export const runQueries = new rpc.RequestType<WithProgressId<EvaluateQueriesPara
  */
 export const runUpgrade = new rpc.RequestType<WithProgressId<RunUpgradeParams>, RunUpgradeResult, void, void>('evaluation/runUpgrade');
 
+export const registerDatabases = new rpc.RequestType<
+  WithProgressId<RegisterDatabasesParams>,
+  RegisterDatabasesResult,
+  void,
+  void
+>('evaluation/registerDatabases');
+
+export const deregisterDatabases = new rpc.RequestType<
+  WithProgressId<DeregisterDatabasesParams>,
+  DeregisterDatabasesResult,
+  void,
+  void
+>('evaluation/deregisterDatabases');
+
 /**
  * Request returned to the client to notify completion of a query.
  * The full runQueries job is completed when all queries are acknowledged.
  */
 export const completeQuery = new rpc.RequestType<EvaluationResult, Record<string, any>, void, void>('evaluation/queryCompleted');
 
-/**
- * A notification that the progress has been changed.
- */
-export const progress = new rpc.NotificationType<ProgressMessage, void>('ql/progressUpdated');
+export const progress = shared.progress;

extensions/ql-vscode/src/pure/location-link-utils.ts

@@ -0,0 +1,15 @@
+import { FileLink } from '../remote-queries/shared/analysis-result';
+
+export function createRemoteFileRef(
+  fileLink: FileLink,
+  startLine?: number,
+  endLine?: number
+): string {
+  if (startLine && endLine) {
+    return `${fileLink.fileLinkPrefix}/${fileLink.filePath}#L${startLine}-L${endLine}`;
+  } else if (startLine) {
+    return `${fileLink.fileLinkPrefix}/${fileLink.filePath}#L${startLine}`;
+  } else {
+    return `${fileLink.fileLinkPrefix}/${fileLink.filePath}`;
+  }
+}

extensions/ql-vscode/src/pure/log-summary-parser.ts

@@ -0,0 +1,34 @@
+import { readJsonlFile } from '../log-insights/jsonl-reader';
+
+// TODO(angelapwen): Only load in necessary information and
+// location in bytes for this log to save memory.
+export interface EvalLogData {
+  predicateName: string;
+  millis: number;
+  resultSize: number;
+  // Key: pipeline identifier; Value: array of pipeline steps
+  ra: Record<string, string[]>;
+}
+
+/**
+ * A pure method that parses a string of evaluator log summaries into
+ * an array of EvalLogData objects.
+ */
+export async function parseViewerData(jsonSummaryPath: string): Promise<EvalLogData[]> {
+  const viewerData: EvalLogData[] = [];
+
+  await readJsonlFile(jsonSummaryPath, async jsonObj => {
+    // Only convert log items that have an RA and millis field
+    if (jsonObj.ra !== undefined && jsonObj.millis !== undefined) {
+      const newLogData: EvalLogData = {
+        predicateName: jsonObj.predicateName,
+        millis: jsonObj.millis,
+        resultSize: jsonObj.resultSize,
+        ra: jsonObj.ra
+      };
+      viewerData.push(newLogData);
+    }
+  });
+
+  return viewerData;
+}

extensions/ql-vscode/src/pure/messages-shared.ts

@@ -0,0 +1,110 @@
+/**
+ * Types for messages exchanged during jsonrpc communication with the
+ * the CodeQL query server.
+ *
+ * This file exists in the queryserver and in the vscode extension, and
+ * should be kept in sync between them.
+ *
+ * A note about the namespaces below, which look like they are
+ * essentially enums, namely Severity, ResultColumnKind, and
+ * QueryResultType. By design, for the sake of extensibility, clients
+ * receiving messages of this protocol are supposed to accept any
+ * number for any of these types. We commit to the given meaning of
+ * the numbers listed in constants in the namespaces, and we commit to
+ * the fact that any unknown QueryResultType value counts as an error.
+ */
+
+import * as rpc from 'vscode-jsonrpc';
+
+/**
+ * A position within a QL file.
+ */
+export interface Position {
+  /**
+   * The one-based index of the start line
+   */
+  line: number;
+  /**
+   * The one-based offset of the start column within
+   * the start line in UTF-16 code-units
+   */
+  column: number;
+  /**
+   * The one-based index of the end line line
+   */
+  endLine: number;
+
+  /**
+   * The one-based offset of the end column within
+   * the end line in UTF-16 code-units
+   */
+  endColumn: number;
+  /**
+   * The path of the file.
+   * If the file name is "Compiler Generated" the
+   * the position is not a real position but
+   * arises from compiler generated code.
+   */
+  fileName: string;
+}
+
+/**
+ * The way of compiling the query, as a normal query
+ * or a subset of it. Note that precisely one of the two options should be set.
+ */
+export interface CompilationTarget {
+  /**
+   * Compile as a normal query
+   */
+  query?: Record<string, never>;
+  /**
+   * Compile as a quick evaluation
+   */
+  quickEval?: QuickEvalOptions;
+}
+
+/**
+ * Options for quick evaluation
+ */
+export interface QuickEvalOptions {
+  quickEvalPos?: Position;
+}
+
+/**
+ * Type for any action that could have progress messages.
+ */
+export interface WithProgressId<T> {
+  /**
+   * The main body
+   */
+  body: T;
+  /**
+   * The id used to report progress updates
+   */
+  progressId: number;
+}
+
+export interface ProgressMessage {
+  /**
+   * The id of the operation that is running
+   */
+  id: number;
+  /**
+   * The current step
+   */
+  step: number;
+  /**
+   * The maximum step. This *should* be constant for a single job.
+   */
+  maxStep: number;
+  /**
+   * The current progress message
+   */
+  message: string;
+}
+
+
+/**
+ * A notification that the progress has been changed.
+ */
+export const progress = new rpc.NotificationType<ProgressMessage, void>('ql/progressUpdated');

extensions/ql-vscode/src/pure/new-messages.ts

@@ -0,0 +1,215 @@
+/**
+ * Types for messages exchanged during jsonrpc communication with the
+ * the CodeQL query server.
+ *
+ * This file exists in the queryserver and in the vscode extension, and
+ * should be kept in sync between them.
+ *
+ * A note about the namespaces below, which look like they are
+ * essentially enums, namely Severity, ResultColumnKind, and
+ * QueryResultType. By design, for the sake of extensibility, clients
+ * receiving messages of this protocol are supposed to accept any
+ * number for any of these types. We commit to the given meaning of
+ * the numbers listed in constants in the namespaces, and we commit to
+ * the fact that any unknown QueryResultType value counts as an error.
+ */
+
+import * as rpc from 'vscode-jsonrpc';
+import * as shared from './messages-shared';
+
+
+
+/**
+ * Parameters to clear the cache
+ */
+export interface ClearCacheParams {
+  /**
+   * The dataset for which we want to clear the cache
+   */
+  db: string;
+  /**
+   * Whether the cache should actually be cleared.
+   */
+  dryRun: boolean;
+}
+
+/**
+ * Parameters for trimming the cache of a dataset
+ */
+export interface TrimCacheParams {
+  /**
+   * The dataset that we want to trim the cache of.
+   */
+  db: string;
+}
+
+/**
+ * The result of trimming or clearing the cache.
+ */
+export interface ClearCacheResult {
+  /**
+   * A user friendly message saying what was or would be
+   * deleted.
+   */
+  deletionMessage: string;
+}
+
+
+export type QueryResultType = number;
+/**
+ * The result of running a query. This namespace is intentionally not
+ * an enum, see "for the sake of extensibility" comment above.
+ */
+// eslint-disable-next-line @typescript-eslint/no-namespace
+export namespace QueryResultType {
+  /**
+   * The query ran successfully
+   */
+  export const SUCCESS = 0;
+  /**
+   * The query failed due to an reason
+   * that isn't listed
+   */
+  export const OTHER_ERROR = 1;
+  /**
+   * The query failed do to compilation erorrs
+   */
+  export const COMPILATION_ERROR = 2;
+  /**
+    * The query failed due to running out of
+    * memory
+    */
+  export const OOM = 3;
+  /**
+   * The query failed because it was cancelled.
+   */
+  export const CANCELLATION = 4;
+  /**
+   * The dbscheme basename was not the same
+   */
+  export const DBSCHEME_MISMATCH_NAME = 5;
+  /**
+   * No upgrade was found
+   */
+  export const DBSCHEME_NO_UPGRADE = 6;
+}
+
+
+export interface RegisterDatabasesParams {
+  databases: string[];
+}
+
+export interface DeregisterDatabasesParams {
+  databases: string[];
+}
+
+export type RegisterDatabasesResult = {
+  registeredDatabases: string[];
+};
+
+export type DeregisterDatabasesResult = {
+  registeredDatabases: string[];
+};
+
+
+export interface RunQueryParams {
+  /**
+   * The path of the query
+   */
+  queryPath: string,
+  /**
+   * The output path
+   */
+  outputPath: string,
+  /**
+   * The database path
+   */
+  db: string,
+  additionalPacks: string[],
+  target: CompilationTarget,
+  externalInputs: Record<string, string>,
+  singletonExternalInputs: Record<string, string>,
+  dilPath?: string,
+  logPath?: string
+}
+
+export interface RunQueryResult {
+  resultType: QueryResultType,
+  message?: string,
+  expectedDbschemeName?: string,
+  evaluationTime: number;
+}
+
+
+
+export interface UpgradeParams {
+  db: string,
+  additionalPacks: string[],
+}
+
+export type UpgradeResult = Record<string, unknown>;
+
+export type ClearPackCacheParams = Record<string, unknown>;
+export type ClearPackCacheResult = Record<string, unknown>;
+
+/**
+ * A position within a QL file.
+ */
+export type Position = shared.Position;
+
+/**
+ * The way of compiling the query, as a normal query
+ * or a subset of it. Note that precisely one of the two options should be set.
+ */
+export type CompilationTarget = shared.CompilationTarget;
+
+export type QuickEvalOptions = shared.QuickEvalOptions;
+
+export type WithProgressId<T> = shared.WithProgressId<T>;
+export type ProgressMessage = shared.ProgressMessage;
+
+/**
+ * Clear the cache of a dataset
+ */
+export const clearCache = new rpc.RequestType<WithProgressId<ClearCacheParams>, ClearCacheResult, void, void>('evaluation/clearCache');
+/**
+ * Trim the cache of a dataset
+ */
+export const trimCache = new rpc.RequestType<WithProgressId<TrimCacheParams>, ClearCacheResult, void, void>('evaluation/trimCache');
+
+/**
+ * Clear the pack cache
+ */
+export const clearPackCache = new rpc.RequestType<WithProgressId<ClearPackCacheParams>, ClearPackCacheResult, void, void>('evaluation/clearPackCache');
+
+/**
+ * Run a query on a database
+ */
+export const runQuery = new rpc.RequestType<WithProgressId<RunQueryParams>, RunQueryResult, void, void>('evaluation/runQuery');
+
+export const registerDatabases = new rpc.RequestType<
+  WithProgressId<RegisterDatabasesParams>,
+  RegisterDatabasesResult,
+  void,
+  void
+>('evaluation/registerDatabases');
+
+export const deregisterDatabases = new rpc.RequestType<
+  WithProgressId<DeregisterDatabasesParams>,
+  DeregisterDatabasesResult,
+  void,
+  void
+>('evaluation/deregisterDatabases');
+
+
+export const upgradeDatabase = new rpc.RequestType<
+  WithProgressId<UpgradeParams>,
+  UpgradeResult,
+  void,
+  void
+>('evaluation/runUpgrade');
+
+/**
+ * A notification that the progress has been changed.
+ */
+export const progress = shared.progress;