feat: Add support for Github Enterprise

README.md

@@ -17,6 +17,7 @@ Code Ownership & Review Assignment Tool - GitHub CODEOWNERS but better
 - [Getting Started](#getting-started)
   - [GitHub Configuration](#github-configuration)
   - [GitHub Teams Support](#github-teams-support)
+  - [GitHub Enterprise](#github-enterprise)
 - [Configuration](#configuration)
   - [.codeowners File Spec](#codeowners-file-spec)
   - [Advanced Configuration](#advanced-configuration)
@@ -112,6 +113,16 @@ It is recommended to also set up a rerun workflow on `pull_request_review` to re
 
 If you plan to have organization teams as code owners, you will need to use a PAT that has organization [read access for Members and Administration](https://docs.github.com/en/rest/authentication/permissions-required-for-fine-grained-personal-access-tokens) as the token. If you do not have organization teams as owners, [GITHUB_TOKEN](https://docs.github.com/en/actions/security-for-github-actions/security-guides/automatic-token-authentication#using-the-github_token-in-a-workflow) should be sufficient.
 
+### GitHub Enterprise
+
+To use a GitHub Enterprise instance instead of the public GitHub API, set the `github-api-url` input:
+
+```yaml
+          github-api-url: 'https://ghe.example.com'
+```
+
+The `/api/v3` suffix is optional. For GitHub Enterprise Cloud with data residency, use `https://api.<tenant>.ghe.com`. If the input is not set, the public GitHub API is used.
+
 ## Configuration
 
 ### .codeowners File Spec

action.yml

@@ -15,6 +15,10 @@ inputs:
     description: 'The owner and repository name.  For example `octocat/Hello-World`'
     required: true
     default: '${{ github.repository }}'
+  github-api-url:
+    description: 'GitHub API base URL. Set for GitHub Enterprise, e.g. https://ghe.example.com/api/v3. Defaults to the public GitHub API.'
+    required: false
+    default: ''
   verbose:
     description: 'Print debug info'
     required: false
@@ -111,6 +115,7 @@ runs:
         INPUT_GITHUB-TOKEN: ${{ inputs.github-token }}
         INPUT_PR: ${{ inputs.pr }}
         INPUT_REPOSITORY: ${{ inputs.repository }}
+        INPUT_GITHUB-API-URL: ${{ inputs.github-api-url }}
         INPUT_VERBOSE: ${{ inputs.verbose }}
         INPUT_QUIET: ${{ inputs.quiet }}
         BIN: ${{ steps.resolve.outputs.bin }}

internal/app/app.go

@@ -52,6 +52,7 @@ func (od *OutputData) UpdateOutputData(success bool, message string, stillRequir
 // Config holds the application configuration
 type Config struct {
 	Token         string
+	ApiUrl        string
 	RepoDir       string
 	PR            int
 	Repo          string
@@ -79,7 +80,7 @@ func New(cfg Config) (*App, error) {
 	owner := repoSplit[0]
 	repo := repoSplit[1]
 
-	client, err := gh.NewClient(owner, repo, cfg.Token)
+	client, err := gh.NewClient(owner, repo, cfg.Token, cfg.ApiUrl)
 	if err != nil {
 		return nil, err
 	}

internal/github/gh.go

@@ -69,8 +69,15 @@ type GHClient struct {
 	infoBuffer      io.Writer
 }
 
-func NewClient(owner, repo, token string) (Client, error) {
-	client, err := github.NewClient(github.WithAuthToken(token))
+func NewClient(owner, repo, token, apiUrl string) (Client, error) {
+	opts := []github.ClientOptionsFunc{github.WithAuthToken(token)}
+	if apiUrl != "" {
+		// WithEnterpriseURLs appends api/uploads/ to the upload URL, so strip
+		// any api/v3 suffix to avoid ending up with api/v3/api/uploads/.
+		uploadUrl := strings.TrimSuffix(strings.TrimSuffix(apiUrl, "/"), "/api/v3")
+		opts = append(opts, github.WithEnterpriseURLs(apiUrl, uploadUrl))
+	}
+	client, err := github.NewClient(opts...)
 	if err != nil {
 		return nil, err
 	}

internal/github/gh_test.go

@@ -322,7 +322,7 @@ func TestIsSubstringInComments(t *testing.T) {
 }
 
 func TestNewGithubClient(t *testing.T) {
-	c, err := NewClient("owner", "repo", "token")
+	c, err := NewClient("owner", "repo", "token", "")
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
 	}
@@ -345,6 +345,77 @@ func TestNewGithubClient(t *testing.T) {
 	if client.userReviewerMap != nil {
 		t.Error("Expected userReviewerMap to be nil")
 	}
+	if got := client.client.BaseURL(); got != "https://api.github.com/" {
+		t.Errorf("Expected base URL to be https://api.github.com/, got %s", got)
+	}
+}
+
+func TestNewGithubClientApiUrl(t *testing.T) {
+	tt := []struct {
+		name           string
+		apiUrl         string
+		expectedBase   string
+		expectedUpload string
+		expectError    bool
+	}{
+		{
+			name:           "empty uses public GitHub",
+			apiUrl:         "",
+			expectedBase:   "https://api.github.com/",
+			expectedUpload: "https://uploads.github.com/",
+		},
+		{
+			name:           "enterprise host",
+			apiUrl:         "https://ghe.example.com",
+			expectedBase:   "https://ghe.example.com/api/v3/",
+			expectedUpload: "https://ghe.example.com/api/uploads/",
+		},
+		{
+			name:           "enterprise host with api/v3",
+			apiUrl:         "https://ghe.example.com/api/v3",
+			expectedBase:   "https://ghe.example.com/api/v3/",
+			expectedUpload: "https://ghe.example.com/api/uploads/",
+		},
+		{
+			name:           "enterprise host with api/v3 and trailing slash",
+			apiUrl:         "https://ghe.example.com/api/v3/",
+			expectedBase:   "https://ghe.example.com/api/v3/",
+			expectedUpload: "https://ghe.example.com/api/uploads/",
+		},
+		{
+			name:           "enterprise cloud with data residency",
+			apiUrl:         "https://api.acme.ghe.com",
+			expectedBase:   "https://api.acme.ghe.com/",
+			expectedUpload: "https://api.acme.ghe.com/",
+		},
+		{
+			name:        "invalid URL",
+			apiUrl:      "://bad",
+			expectError: true,
+		},
+	}
+
+	for _, tc := range tt {
+		t.Run(tc.name, func(t *testing.T) {
+			c, err := NewClient("owner", "repo", "token", tc.apiUrl)
+			if tc.expectError {
+				if err == nil {
+					t.Fatal("expected error but got none")
+				}
+				return
+			}
+			if err != nil {
+				t.Fatalf("unexpected error: %v", err)
+			}
+			gh := c.(*GHClient)
+			if got := gh.client.BaseURL(); got != tc.expectedBase {
+				t.Errorf("Expected base URL to be %s, got %s", tc.expectedBase, got)
+			}
+			if got := gh.client.UploadURL(); got != tc.expectedUpload {
+				t.Errorf("Expected upload URL to be %s, got %s", tc.expectedUpload, got)
+			}
+		})
+	}
 }
 
 func TestNilPRErr(t *testing.T) {
@@ -1464,7 +1535,7 @@ func TestContainsValidBypassApproval(t *testing.T) {
 }
 
 func TestContainsValidBypassApprovalNoPR(t *testing.T) {
-	c, err := NewClient("test-owner", "test-repo", "test-token")
+	c, err := NewClient("test-owner", "test-repo", "test-token", "")
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
 	}

main.go

@@ -16,6 +16,7 @@ import (
 // Flags holds the command line flags
 type Flags struct {
 	Token   *string
+	ApiUrl  *string
 	RepoDir *string
 	PR      *int
 	Repo    *string
@@ -26,6 +27,7 @@ type Flags struct {
 var (
 	flags = &Flags{
 		Token:   flag.String("token", getEnv("INPUT_GITHUB-TOKEN", ""), "GitHub authentication token"),
+		ApiUrl:  flag.String("api-url", getEnv("INPUT_GITHUB-API-URL", ""), "GitHub API base URL (for GitHub Enterprise, e.g. https://ghe.example.com/api/v3)"),
 		RepoDir: flag.String("dir", getEnv("GITHUB_WORKSPACE", "/"), "Path to local Git repo"),
 		PR:      flag.Int("pr", ignoreError(strconv.Atoi(getEnv("INPUT_PR", ""))), "Pull Request number"),
 		Repo:    flag.String("repo", getEnv("INPUT_REPOSITORY", ""), "GitHub repo name"),
@@ -127,6 +129,7 @@ func main() {
 
 	cfg := app.Config{
 		Token:         *flags.Token,
+		ApiUrl:        *flags.ApiUrl,
 		RepoDir:       *flags.RepoDir,
 		PR:            *flags.PR,
 		Repo:          *flags.Repo,