Go: Detect and apply proxy settings (WIP)

go/extractor/toolchain/toolchain.go

@@ -139,7 +139,9 @@ func SupportsWorkspaces() bool {
 
 // Constructs a `*exec.Cmd` for `go` with the specified arguments.
 func GoCommand(arg ...string) *exec.Cmd {
-	return exec.Command("go", arg...)
+	cmd := exec.Command("go", arg...)
+	util.ApplyProxyEnvVars(cmd)
+	return cmd
 }
 
 // Run `go mod tidy -e` in the directory given by `path`.

go/extractor/util/BUILD.bazel

@@ -6,6 +6,7 @@ go_library(
     name = "util",
     srcs = [
         "extractvendordirs.go",
+        "registryproxy.go",
         "semver.go",
         "util.go",
     ],
@@ -17,6 +18,7 @@ go_library(
 go_test(
     name = "util_test",
     srcs = [
+        "registryproxy_test.go",
         "semver_test.go",
         "util_test.go",
     ],

go/extractor/util/registryproxy.go

@@ -0,0 +1,114 @@
+package util
+
+import (
+	"encoding/json"
+	"fmt"
+	"log/slog"
+	"os"
+	"os/exec"
+	"strings"
+)
+
+const PROXY_HOST = "CODEQL_PROXY_HOST"
+const PROXY_PORT = "CODEQL_PROXY_PORT"
+const PROXY_CA_CERTIFICATE = "CODEQL_PROXY_CA_CERTIFICATE"
+const PROXY_URLS = "CODEQL_PROXY_URLS"
+const GOPROXY_SERVER = "goproxy_server"
+
+type RegistryConfig struct {
+	Type string `json:"type"`
+	URL  string `json:"url"`
+}
+
+var proxy_address string
+var proxy_cert_file string
+var proxy_configs []RegistryConfig
+
+// Tries to parse the given string value into an array of RegistryConfig values.
+func parseRegistryConfigs(str string) ([]RegistryConfig, error) {
+	var configs []RegistryConfig
+	if err := json.Unmarshal([]byte(str), &configs); err != nil {
+		return nil, err
+	}
+
+	return configs, nil
+}
+
+func checkEnvVars() {
+	if proxy_host, proxy_host_set := os.LookupEnv(PROXY_HOST); proxy_host_set {
+		if proxy_port, proxy_port_set := os.LookupEnv(PROXY_PORT); proxy_port_set {
+			proxy_address = fmt.Sprintf("http://%s:%s", proxy_host, proxy_port)
+			slog.Info("Found private registry proxy", slog.String("proxy_address", proxy_address))
+		}
+	}
+
+	if proxy_cert, proxy_cert_set := os.LookupEnv(PROXY_CA_CERTIFICATE); proxy_cert_set {
+		// Write the certificate to a temporary file
+		slog.Info("Found certificate")
+
+		f, err := os.CreateTemp("", "codeql-proxy.crt")
+		if err != nil {
+			slog.Error("Unable to create temporary file for the proxy certificate", slog.String("error", err.Error()))
+		}
+
+		_, err = f.WriteString(proxy_cert)
+		if err != nil {
+			slog.Error("Failed to write to the temporary certificate file", slog.String("error", err.Error()))
+		}
+
+		err = f.Close()
+		if err != nil {
+			slog.Error("Failed to close the temporary certificate file", slog.String("error", err.Error()))
+		} else {
+			proxy_cert_file = f.Name()
+		}
+	}
+
+	if proxy_urls, proxy_urls_set := os.LookupEnv(PROXY_URLS); proxy_urls_set {
+		val, err := parseRegistryConfigs(proxy_urls)
+		if err != nil {
+			slog.Error("Unable to parse proxy configurations", slog.String("error", err.Error()))
+		} else {
+			// We only care about private registry configurations that are relevant to Go and
+			// filter others out at this point.
+			proxy_configs = make([]RegistryConfig, 0)
+			for _, cfg := range val {
+				if cfg.Type == GOPROXY_SERVER {
+					proxy_configs = append(proxy_configs, cfg)
+					slog.Info("Found GOPROXY server", slog.String("url", cfg.URL))
+				}
+			}
+		}
+	}
+}
+
+// Applies private package proxy related environment variables to `cmd`.
+func ApplyProxyEnvVars(cmd *exec.Cmd) {
+	slog.Info(
+		"Applying private registry proxy environment variables",
+		slog.String("cmd_args", strings.Join(cmd.Args, " ")),
+	)
+
+	checkEnvVars()
+
+	if proxy_address != "" {
+		cmd.Env = append(cmd.Env, fmt.Sprintf("HTTP_PROXY=%s", proxy_address))
+		cmd.Env = append(cmd.Env, fmt.Sprintf("HTTPS_PROXY=%s", proxy_address))
+	}
+	if proxy_cert_file != "" {
+		slog.Info("Setting SSL_CERT_FILE", slog.String("proxy_cert_file", proxy_cert_file))
+		cmd.Env = append(cmd.Env, fmt.Sprintf("SSL_CERT_FILE=%s", proxy_cert_file))
+	}
+
+	if len(proxy_configs) > 0 {
+		goproxy_val := "https://proxy.golang.org,direct"
+
+		for _, cfg := range proxy_configs {
+			goproxy_val = cfg.URL + "," + goproxy_val
+		}
+
+		cmd.Env = append(cmd.Env, fmt.Sprintf("GOPROXY=%s", goproxy_val))
+		cmd.Env = append(cmd.Env, "GOPRIVATE=")
+		cmd.Env = append(cmd.Env, "GONOPROXY=")
+	}
+}

go/extractor/util/registryproxy_test.go

@@ -0,0 +1,49 @@
+package util
+
+import (
+	"testing"
+)
+
+func parseRegistryConfigsFail(t *testing.T, str string) {
+	_, err := parseRegistryConfigs(str)
+
+	if err == nil {
+		t.Fatal("Expected `parseRegistryConfigs` to fail, but it succeeded.")
+	}
+}
+
+func parseRegistryConfigsSuccess(t *testing.T, str string) []RegistryConfig {
+	val, err := parseRegistryConfigs(str)
+
+	if err != nil {
+		t.Fatalf("Expected `parseRegistryConfigs` to succeed, but it failed: %s", err.Error())
+	}
+
+	return val
+}
+
+func TestParseRegistryConfigs(t *testing.T) {
+	// parseRegistryConfigsFail(t, "")
+
+	empty := parseRegistryConfigsSuccess(t, "[]")
+
+	if len(empty) != 0 {
+		t.Fatal("Expected `parseRegistryConfigs(\"[]\")` to return no configurations, but got some.")
+	}
+
+	single := parseRegistryConfigsSuccess(t, "[{ \"type\": \"goproxy_server\", \"url\": \"https://proxy.example.com/mod\" }]")
+
+	if len(single) != 1 {
+		t.Fatalf("Expected `parseRegistryConfigs` to return one configuration, but got %d.", len(single))
+	}
+
+	first := single[0]
+
+	if first.Type != "goproxy_server" {
+		t.Fatalf("Expected `Type` to be `goproxy_server`, but got `%s`", first.Type)
+	}
+
+	if first.URL != "https://proxy.example.com/mod" {
+		t.Fatalf("Expected `URL` to be `https://proxy.example.com/mod`, but got `%s`", first.URL)
+	}
+}