New command to add database source folder to workspace

extensions/ql-vscode/package.json

@@ -345,6 +345,10 @@
         "command": "codeQLDatabases.openDatabaseFolder",
         "title": "Show Database Directory"
       },
+      {
+        "command": "codeQLDatabases.addDatabaseSource",
+        "title": "Add Database Source to Workspace"
+      },
       {
         "command": "codeQL.chooseDatabaseFolder",
         "title": "CodeQL: Choose Database from Folder"
@@ -584,6 +588,11 @@
           "group": "9_qlCommands",
           "when": "view == codeQLDatabases"
         },
+        {
+          "command": "codeQLDatabases.addDatabaseSource",
+          "group": "9_qlCommands",
+          "when": "view == codeQLDatabases"
+        },
         {
           "command": "codeQLQueryHistory.openQuery",
           "group": "9_qlCommands",
@@ -707,6 +716,10 @@
           "command": "codeQLDatabases.openDatabaseFolder",
           "when": "false"
         },
+        {
+          "command": "codeQLDatabases.addDatabaseSource",
+          "when": "false"
+        },
         {
           "command": "codeQLDatabases.sortByName",
           "when": "false"

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

@@ -348,6 +348,12 @@ export class DatabaseUI extends DisposableObject {
         this.handleOpenFolder
       )
     );
+    this.push(
+      commandRunner(
+        'codeQLDatabases.addDatabaseSource',
+        this.handleAddSource
+      )
+    );
     this.push(
       commandRunner(
         'codeQLDatabases.removeOrphanedDatabases',
@@ -632,6 +638,25 @@ 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) {
+      // TODO: This multiselect part doesn't work yet. Only the first databases is re-added.
+      await Promise.all(
+        multiSelect.map((dbItem) => 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

extensions/ql-vscode/src/databases.ts

@@ -587,7 +587,7 @@ export class DatabaseManager extends DisposableObject {
     }));
   }
 
-  private async addDatabaseSourceArchiveFolder(item: DatabaseItem) {
+  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);