plugin: support GitHub Enterprise Server as plugin source (#1751)

plugin/install.go

@@ -16,6 +16,8 @@ import (
 	"golang.org/x/oauth2"
 )
 
+const defaultSourceHost = "github.com"
+
 // InstallConfig is a config for plugin installation.
 // This is a wrapper for PluginConfig and manages naming conventions
 // and directory names for installation.
@@ -149,9 +151,12 @@ func (c *InstallConfig) fetchReleaseAssets() (map[string]*github.ReleaseAsset, e
 	assets := map[string]*github.ReleaseAsset{}
 
 	ctx := context.Background()
-	client := newGitHubClient(ctx)
 
-	log.Printf("[DEBUG] Request to https://api.github.com/repos/%s/%s/releases/tags/%s", c.SourceOwner, c.SourceRepo, c.TagName())
+	client, err := newGitHubClient(ctx, c)
+	if err != nil {
+		return assets, err
+	}
+
 	release, _, err := client.Repositories.GetReleaseByTag(ctx, c.SourceOwner, c.SourceRepo, c.TagName())
 	if err != nil {
 		return assets, err
@@ -172,9 +177,12 @@ func (c *InstallConfig) downloadToTempFile(asset *github.ReleaseAsset) (*os.File
 	}
 
 	ctx := context.Background()
-	client := newGitHubClient(ctx)
 
-	log.Printf("[DEBUG] Request to https://api.github.com/repos/%s/%s/releases/assets/%d", c.SourceOwner, c.SourceRepo, asset.GetID())
+	client, err := newGitHubClient(ctx, c)
+	if err != nil {
+		return nil, err
+	}
+
 	downloader, _, err := client.Repositories.DownloadReleaseAsset(ctx, c.SourceOwner, c.SourceRepo, asset.GetID(), http.DefaultClient)
 	if err != nil {
 		return nil, err
@@ -237,18 +245,27 @@ func extractFileFromZipFile(zipFile *os.File, savePath string) error {
 	return nil
 }
 
-func newGitHubClient(ctx context.Context) *github.Client {
-	token := os.Getenv("GITHUB_TOKEN")
-	if token == "" {
-		return github.NewClient(nil)
+func newGitHubClient(ctx context.Context, config *InstallConfig) (*github.Client, error) {
+	hc := &http.Client{
+		Transport: http.DefaultTransport,
 	}
 
-	log.Printf("[DEBUG] GITHUB_TOKEN set, plugin requests to the GitHub API will be authenticated")
+	if t := os.Getenv("GITHUB_TOKEN"); t != "" {
+		log.Printf("[DEBUG] GITHUB_TOKEN set, plugin requests to the GitHub API will be authenticated")
 
-	ts := oauth2.StaticTokenSource(
-		&oauth2.Token{AccessToken: token},
-	)
-	return github.NewClient(oauth2.NewClient(ctx, ts))
+		hc = oauth2.NewClient(ctx, oauth2.StaticTokenSource(&oauth2.Token{
+			AccessToken: t,
+		}))
+	}
+
+	hc.Transport = &requestLoggingTransport{hc.Transport}
+
+	if config.SourceHost == defaultSourceHost {
+		return github.NewClient(hc), nil
+	}
+
+	baseURL := fmt.Sprintf("https://%s/", config.SourceHost)
+	return github.NewEnterpriseClient(baseURL, baseURL, hc)
 }
 
 func fileExt() string {
@@ -257,3 +274,13 @@ func fileExt() string {
 	}
 	return ""
 }
+
+// requestLoggingTransport wraps an existing RoundTripper and prints DEBUG logs before each request
+type requestLoggingTransport struct {
+	http.RoundTripper
+}
+
+func (s *requestLoggingTransport) RoundTrip(r *http.Request) (*http.Response, error) {
+	log.Printf("[DEBUG] Request to %s", r.URL)
+	return s.RoundTripper.RoundTrip(r)
+}

plugin/install_test.go

@@ -1,6 +1,7 @@
 package plugin
 
 import (
+	"context"
 	"os"
 	"testing"
 
@@ -17,6 +18,7 @@ func Test_Install(t *testing.T) {
 		Enabled:     true,
 		Version:     "0.4.0",
 		Source:      "github.com/terraform-linters/tflint-ruleset-aws",
+		SourceHost:  "github.com",
 		SourceOwner: "terraform-linters",
 		SourceRepo:  "tflint-ruleset-aws",
 	})
@@ -40,3 +42,45 @@ func Test_Install(t *testing.T) {
 		t.Fatalf("Installed binary name is invalid: expected=%s, got=%s", expected, info.Name())
 	}
 }
+
+func TestNewGitHubClient(t *testing.T) {
+	cases := []struct {
+		name     string
+		config   *InstallConfig
+		expected string
+	}{
+		{
+			name: "default",
+			config: &InstallConfig{
+				PluginConfig: &tflint.PluginConfig{
+					SourceHost: "github.com",
+				},
+			},
+			expected: "https://api.github.com/",
+		},
+		{
+			name: "enterprise",
+			config: &InstallConfig{
+				PluginConfig: &tflint.PluginConfig{
+					SourceHost: "github.example.com",
+				},
+			},
+			expected: "https://github.example.com/api/v3/",
+		},
+	}
+
+	for _, tc := range cases {
+		tc := tc
+
+		t.Run(tc.name, func(t *testing.T) {
+			client, err := newGitHubClient(context.Background(), tc.config)
+			if err != nil {
+				t.Fatalf("Failed to create client: %s", err)
+			}
+
+			if client.BaseURL.String() != tc.expected {
+				t.Fatalf("Unexpected API URL: want %s, got %s", tc.expected, client.BaseURL.String())
+			}
+		})
+	}
+}

tflint/config.go

@@ -101,6 +101,7 @@ type PluginConfig struct {
 	Body hcl.Body `hcl:",remain"`
 
 	// Parsed source attributes
+	SourceHost  string
 	SourceOwner string
 	SourceRepo  string
 }
@@ -477,11 +478,10 @@ func (c *PluginConfig) validate() error {
 		parts := strings.Split(c.Source, "/")
 		// Expected `github.com/owner/repo` format
 		if len(parts) != 3 {
-			return fmt.Errorf("plugin `%s`: `source` is invalid. Must be in the format `github.com/owner/repo`", c.Name)
-		}
-		if parts[0] != "github.com" {
-			return fmt.Errorf("plugin `%s`: `source` is invalid. Hostname must be `github.com`", c.Name)
+			return fmt.Errorf("plugin `%s`: `source` is invalid. Must be a GitHub reference in the format `${host}/${owner}/${repo}`", c.Name)
 		}
+
+		c.SourceHost = parts[0]
 		c.SourceOwner = parts[1]
 		c.SourceRepo = parts[2]
 	}

tflint/config_test.go

@@ -107,6 +107,7 @@ plugin "baz" {
 						Version:     "0.1.0",
 						Source:      "github.com/foo/bar",
 						SigningKey:  "SIGNING_KEY",
+						SourceHost:  "github.com",
 						SourceOwner: "foo",
 						SourceRepo:  "bar",
 					},
@@ -276,24 +277,46 @@ plugin "foo" {
 }`,
 			},
 			errCheck: func(err error) bool {
-				return err == nil || err.Error() != "plugin `foo`: `source` is invalid. Must be in the format `github.com/owner/repo`"
+				return err == nil || err.Error() != "plugin `foo`: `source` is invalid. Must be a GitHub reference in the format `${host}/${owner}/${repo}`"
 			},
 		},
 		{
-			name: "plugin with invalid source host",
-			file: "plugin_with_invalid_source_host.hcl",
+			name: "plugin with GHES source host",
+			file: "plugin_with_ghes_source_host.hcl",
 			files: map[string]string{
-				"plugin_with_invalid_source_host.hcl": `
+				"plugin_with_ghes_source_host.hcl": `
 plugin "foo" {
 	enabled = true
 
 	version = "0.1.0"
-	source = "gitlab.com/foo/bar"
+	source = "github.example.com/foo/bar"
 }`,
 			},
-			errCheck: func(err error) bool {
-				return err == nil || err.Error() != "plugin `foo`: `source` is invalid. Hostname must be `github.com`"
+			want: &Config{
+				Module:            false,
+				Force:             false,
+				IgnoreModules:     map[string]bool{},
+				Varfiles:          []string{},
+				Variables:         []string{},
+				DisabledByDefault: false,
+				Rules:             map[string]*RuleConfig{},
+				Plugins: map[string]*PluginConfig{
+					"foo": {
+						Name:        "foo",
+						Enabled:     true,
+						Version:     "0.1.0",
+						Source:      "github.example.com/foo/bar",
+						SourceHost:  "github.example.com",
+						SourceOwner: "foo",
+						SourceRepo:  "bar",
+					},
+					"terraform": {
+						Name:    "terraform",
+						Enabled: true,
+					},
+				},
 			},
+			errCheck: neverHappend,
 		},
 	}