feat: Add ability to disable features via flags (#223)

cmd/lsif-go/args.go

@@ -17,16 +17,18 @@ var app = kingpin.New(
 ).Version(version + ", protocol version " + protocol.Version)
 
 var (
-	outFile          string
-	projectRoot      string
-	moduleRoot       string
-	repositoryRoot   string
-	repositoryRemote string
-	moduleVersion    string
-	verbosity        int
-	noOutput         bool
-	noAnimation      bool
-	depBatchSize     int
+	outFile               string
+	projectRoot           string
+	moduleRoot            string
+	repositoryRoot        string
+	repositoryRemote      string
+	moduleVersion         string
+	verbosity             int
+	noOutput              bool
+	noAnimation           bool
+	depBatchSize          int
+	enableApiDocs         bool
+	enableImplementations bool
 )
 
 func init() {
@@ -51,6 +53,10 @@ func init() {
 	app.Flag("no-animation", "Do not animate output.").Default("false").BoolVar(&noAnimation)
 
 	app.Flag("dep-batch-size", "How many dependencies to load at once to limit memory usage (e.g. 100). 0 means load all at once.").Default("0").IntVar(&depBatchSize)
+
+	// Feature flags
+	app.Flag("enable-api-docs", "Enable Sourcegraph API Doc generation").Default("true").BoolVar(&enableApiDocs)
+	app.Flag("enable-implementations", "Enable textDocument/implementation generation").Default("true").BoolVar(&enableImplementations)
 }
 
 func parseArgs(args []string) (err error) {

cmd/lsif-go/index.go

@@ -12,7 +12,7 @@ import (
 	"github.com/sourcegraph/sourcegraph/lib/codeintel/lsif/protocol/writer"
 )
 
-func writeIndex(repositoryRoot, repositoryRemote, projectRoot, moduleName, moduleVersion string, dependencies map[string]gomod.GoModule, projectDependencies []string, outFile string, outputOptions output.Options, depBatchSize int) error {
+func writeIndex(repositoryRoot, repositoryRemote, projectRoot, moduleName, moduleVersion string, dependencies map[string]gomod.GoModule, projectDependencies []string, outFile string, outputOptions output.Options, generationOptions indexer.GenerationOptions) error {
 	start := time.Now()
 
 	out, err := os.Create(outFile)
@@ -44,7 +44,7 @@ func writeIndex(repositoryRoot, repositoryRemote, projectRoot, moduleName, modul
 		writer.NewJSONWriter(out),
 		packageDataCache,
 		outputOptions,
-		depBatchSize,
+		generationOptions,
 	)
 
 	if err := indexer.Index(); err != nil {

cmd/lsif-go/main.go

@@ -7,6 +7,7 @@ import (
 
 	"github.com/sourcegraph/lsif-go/internal/git"
 	"github.com/sourcegraph/lsif-go/internal/gomod"
+	"github.com/sourcegraph/lsif-go/internal/indexer"
 	"github.com/sourcegraph/lsif-go/internal/output"
 )
 
@@ -65,6 +66,11 @@ func mainErr() (err error) {
 		return fmt.Errorf("failed to list project dependencies: %v", err)
 	}
 
+	generationOptions := indexer.NewGenerationOptions()
+	generationOptions.EnableApiDocs = enableApiDocs
+	generationOptions.EnableImplementations = enableImplementations
+	generationOptions.DepBatchSize = depBatchSize
+
 	if err := writeIndex(
 		repositoryRoot,
 		repositoryRemote,
@@ -75,7 +81,7 @@ func mainErr() (err error) {
 		projectDependencies,
 		outFile,
 		outputOptions,
-		depBatchSize,
+		generationOptions,
 	); err != nil {
 		return fmt.Errorf("failed to index: %v", err)
 	}

internal/indexer/documentation.go

@@ -48,6 +48,10 @@ func (e emittedDocumentationResults) addAll(other emittedDocumentationResults) m
 
 // indexDocumentation indexes all packages in the project.
 func (i *Indexer) indexDocumentation() error {
+	if !i.generationOptions.EnableApiDocs {
+		return nil
+	}
+
 	var (
 		d                     = &docsIndexer{i: i}
 		mu                    sync.Mutex

internal/indexer/implementation.go

@@ -138,6 +138,10 @@ func (rel *implRelation) linkInterfaceToReceivers(idx int, interfaceMethods []st
 // NOTE: if indexImplementations becomes multi-threaded then we would need to update
 // Indexer.ensureImplementationMoniker to ensure that it uses appropriate locking.
 func (i *Indexer) indexImplementations() error {
+	if !i.generationOptions.EnableImplementations {
+		return nil
+	}
+
 	var implErr error
 
 	output.WithProgress("Indexing implementations", func() {
@@ -392,7 +396,7 @@ func (i *Indexer) extractInterfacesAndConcreteTypes(pkgNames []string) (interfac
 	for ix, pkgName := range pkgNames {
 		pkgBatch = append(pkgBatch, pkgName)
 
-		if i.depBatchSize != 0 && ix%i.depBatchSize == 0 {
+		if i.generationOptions.DepBatchSize != 0 && ix%i.generationOptions.DepBatchSize == 0 {
 			err := batch(pkgBatch)
 			runtime.GC() // Prevent a garbage pile
 			if err != nil {

internal/indexer/indexer.go

@@ -30,6 +30,20 @@ type importMonikerReference struct {
 }
 type setVal interface{}
 
+type GenerationOptions struct {
+	EnableApiDocs         bool
+	EnableImplementations bool
+	DepBatchSize          int
+}
+
+func NewGenerationOptions() GenerationOptions {
+	return GenerationOptions{
+		EnableApiDocs:         true,
+		EnableImplementations: true,
+		DepBatchSize:          0,
+	}
+}
+
 type Indexer struct {
 	repositoryRoot      string                    // path to repository
 	repositoryRemote    string                    // import path inferred by git remote
@@ -79,7 +93,7 @@ type Indexer struct {
 
 	importMonikerChannel chan importMonikerReference
 
-	depBatchSize int
+	generationOptions GenerationOptions
 }
 
 func New(
@@ -94,7 +108,7 @@ func New(
 	jsonWriter writer.JSONWriter,
 	packageDataCache *PackageDataCache,
 	outputOptions output.Options,
-	depBatchSize int,
+	generationOptions GenerationOptions,
 ) *Indexer {
 	return &Indexer{
 		repositoryRoot:           repositoryRoot,
@@ -124,7 +138,7 @@ func New(
 		packageDataCache:         packageDataCache,
 		stripedMutex:             newStripedMutex(),
 		importMonikerChannel:     make(chan importMonikerReference, 512),
-		depBatchSize:             depBatchSize,
+		generationOptions:        generationOptions,
 	}
 }
 

internal/indexer/indexer_test.go

@@ -46,7 +46,7 @@ func TestIndexer(t *testing.T) {
 		w,
 		NewPackageDataCache(),
 		output.Options{},
-		0,
+		NewGenerationOptions(),
 	)
 
 	if err := indexer.Index(); err != nil {
@@ -651,7 +651,7 @@ func TestIndexer_documentation(t *testing.T) {
 				writer.NewJSONWriter(&buf),
 				NewPackageDataCache(),
 				output.Options{},
-				0,
+				NewGenerationOptions(),
 			)
 			if err := indexer.Index(); err != nil {
 				t.Fatalf("unexpected error indexing testdata: %s", err.Error())
@@ -691,7 +691,7 @@ func TestIndexer_shouldVisitPackage(t *testing.T) {
 		w,
 		NewPackageDataCache(),
 		output.Options{},
-		0,
+		NewGenerationOptions(),
 	)
 
 	if err := indexer.loadPackages(false); err != nil {