feat: generate_blocked field in per-library configuration (#2221)

For #897. This change implements the "generate" command.

When library config has generate_blocked field set to true, the generate
command skips the library processing.

If the library is explicitly specified in the argument via "--library",
then this Librarian CLI processes the library.

Author: suztomo

doc/config-schema.md

@@ -29,6 +29,7 @@ Each object in the `libraries` list represents a single library and has the foll
 |-------------------------|--------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------|----------|-----------------------------------------------------------|
 | `id`           | string | A unique identifier for the library, in a language-specific format. It should not be empty and only contains alphanumeric characters, slashes, periods, underscores, and hyphens. | Yes      | Must be a valid library ID.                               |
 | `next_version` | string | The next released version of the library. Ignored unless it would increase the release version.                                                                                   | No       | Must be a valid semantic version, "v" prefix is optional. |
+| `generate_blocked` | bool | Set this to `true` to skip the generation of this library. It's `false` by default. | No       |  |
 
 ## Example
 
@@ -54,4 +55,5 @@ global_files_allowlist:
 libraries:
   - id: "example-library"
     next_version: "2.3.4"
+    generate_blocked: false
 ```

internal/config/librarian_config.go

@@ -32,8 +32,9 @@ type LibrarianConfig struct {
 
 // LibraryConfig defines configuration for a single library, identified by its ID.
 type LibraryConfig struct {
-	LibraryID   string `yaml:"id"`
-	NextVersion string `yaml:"next_version"`
+	LibraryID       string `yaml:"id"`
+	NextVersion     string `yaml:"next_version"`
+	GenerateBlocked bool   `yaml:"generate_blocked"`
 }
 
 // GlobalFile defines the global files in language repositories.

internal/librarian/generate.go

@@ -46,6 +46,7 @@ type generateRunner struct {
 	repo            gitrepo.Repository
 	sourceRepo      gitrepo.Repository
 	state           *config.LibrarianState
+	librarianConfig *config.LibrarianConfig
 	workRoot        string
 }
 
@@ -69,6 +70,7 @@ func newGenerateRunner(cfg *config.Config) (*generateRunner, error) {
 		repo:            runner.repo,
 		sourceRepo:      runner.sourceRepo,
 		state:           runner.state,
+		librarianConfig: runner.librarianConfig,
 		workRoot:        runner.workRoot,
 	}, nil
 }
@@ -101,7 +103,16 @@ func (r *generateRunner) run(ctx context.Context) error {
 	} else {
 		succeededGenerations := 0
 		failedGenerations := 0
+		blockedGenerations := 0
 		for _, library := range r.state.Libraries {
+			if r.librarianConfig != nil {
+				libConfig := r.librarianConfig.LibraryConfigFor(library.ID)
+				if libConfig != nil && libConfig.GenerateBlocked {
+					slog.Info("library has generate_blocked, skipping", "id", library.ID)
+					blockedGenerations++
+					continue
+				}
+			}
 			oldCommit, err := r.generateSingleLibrary(ctx, library.ID, outputDir)
 			if err != nil {
 				slog.Error("failed to generate library", "id", library.ID, "err", err)
@@ -119,9 +130,11 @@ func (r *generateRunner) run(ctx context.Context) error {
 			"generation statistics",
 			"all", len(r.state.Libraries),
 			"successes", succeededGenerations,
+			"blocked", blockedGenerations,
 			"failures", failedGenerations)
-		if failedGenerations > 0 && failedGenerations == len(r.state.Libraries) {
-			return fmt.Errorf("all %d libraries failed to generate", failedGenerations)
+		if failedGenerations > 0 && failedGenerations+blockedGenerations == len(r.state.Libraries) {
+			return fmt.Errorf("all %d libraries failed to generate (blocked: %d)",
+				failedGenerations, blockedGenerations)
 		}
 	}
 

internal/librarian/generate_test.go

@@ -551,6 +551,7 @@ func TestGenerateScenarios(t *testing.T) {
 		api                string
 		library            string
 		state              *config.LibrarianState
+		librarianConfig    *config.LibrarianConfig
 		container          *mockContainerClient
 		ghClient           GitHubClient
 		build              bool
@@ -830,6 +831,92 @@ func TestGenerateScenarios(t *testing.T) {
 			wantGenerateCalls: 2,
 			wantBuildCalls:    1,
 		},
+		{
+			name: "generate skips blocked libraries",
+			state: &config.LibrarianState{
+				Image: "gcr.io/test/image:v1.2.3",
+				Libraries: []*config.LibraryState{
+					{
+						ID:   "google.cloud.texttospeech.v1",
+						APIs: []*config.API{{Path: "google/cloud/texttospeech/v1"}},
+					},
+					{
+						ID:   "google.cloud.vision.v1",
+						APIs: []*config.API{{Path: "google/cloud/vision/v1"}},
+					},
+				},
+			},
+			librarianConfig: &config.LibrarianConfig{
+				Libraries: []*config.LibraryConfig{
+					{LibraryID: "google.cloud.texttospeech.v1"},
+					{LibraryID: "google.cloud.vision.v1", GenerateBlocked: true},
+				},
+			},
+			container: &mockContainerClient{
+				wantLibraryGen: true,
+			},
+			ghClient:          &mockGitHubClient{},
+			build:             true,
+			wantGenerateCalls: 1,
+			wantBuildCalls:    1,
+		},
+		{
+			name:    "generate runs blocked libraries if explicitly requested",
+			library: "google.cloud.vision.v1",
+			state: &config.LibrarianState{
+				Image: "gcr.io/test/image:v1.2.3",
+				Libraries: []*config.LibraryState{
+					{
+						ID:   "google.cloud.texttospeech.v1",
+						APIs: []*config.API{{Path: "google/cloud/texttospeech/v1"}},
+					},
+					{
+						ID:   "google.cloud.vision.v1",
+						APIs: []*config.API{{Path: "google/cloud/vision/v1"}},
+					},
+				},
+			},
+			librarianConfig: &config.LibrarianConfig{
+				Libraries: []*config.LibraryConfig{
+					{LibraryID: "google.cloud.texttospecech.v1"},
+					{LibraryID: "google.cloud.vision.v1", GenerateBlocked: true},
+				},
+			},
+			container: &mockContainerClient{
+				wantLibraryGen: true,
+			},
+			ghClient:          &mockGitHubClient{},
+			build:             true,
+			wantGenerateCalls: 1,
+			wantBuildCalls:    1,
+		},
+		{
+			name: "generate skips a blocked library and the rest fail. should report error",
+			state: &config.LibrarianState{
+				Image: "gcr.io/test/image:v1.2.3",
+				Libraries: []*config.LibraryState{
+					{
+						ID:   "google.cloud.texttospeech.v1",
+						APIs: []*config.API{{Path: "google/cloud/texttospeech/v1"}},
+					},
+					{
+						ID:   "google.cloud.vision.v1",
+						APIs: []*config.API{{Path: "google/cloud/vision/v1"}},
+					},
+				},
+			},
+			librarianConfig: &config.LibrarianConfig{
+				Libraries: []*config.LibraryConfig{
+					{LibraryID: "google.cloud.texttospeech.v1"},
+					{LibraryID: "google.cloud.vision.v1", GenerateBlocked: true},
+				},
+			},
+			container:  &mockContainerClient{generateErr: errors.New("generate error")},
+			ghClient:   &mockGitHubClient{},
+			build:      true,
+			wantErr:    true,
+			wantErrMsg: "all 1 libraries failed to generate (blocked: 1)",
+		},
 		{
 			name: "generate all, all fail should report error",
 			state: &config.LibrarianState{
@@ -885,6 +972,7 @@ func TestGenerateScenarios(t *testing.T) {
 				repo:            repo,
 				sourceRepo:      newTestGitRepo(t),
 				state:           test.state,
+				librarianConfig: test.librarianConfig,
 				containerClient: test.container,
 				ghClient:        test.ghClient,
 				workRoot:        t.TempDir(),