Merge pull request #452 from pjbgf/feature-nolibgit2

gogit: Add new ForceGoGitImplementation FeatureGate

Author: Paulo Gomes

controllers/imageupdateautomation_controller.go

@@ -86,6 +86,8 @@ type ImageUpdateAutomationReconciler struct {
 	helper.Metrics
 
 	NoCrossNamespaceRef bool
+
+	features map[string]bool
 }
 
 type ImageUpdateAutomationReconcilerOptions struct {
@@ -255,8 +257,13 @@ func (r *ImageUpdateAutomationReconciler) Reconcile(ctx context.Context, req ctr
 		return failWithError(err)
 	}
 
+	gitImplementation := origin.Spec.GitImplementation
+	if goGitOnly, _ := r.features[features.ForceGoGitImplementation]; goGitOnly {
+		gitImplementation = sourcev1.GoGitImplementation
+	}
+
 	var gitClient git.RepositoryClient
-	switch origin.Spec.GitImplementation {
+	switch gitImplementation {
 	case sourcev1.LibGit2Implementation:
 		gitClient, err = libgit2.NewClient(tmp, authOpts)
 	case sourcev1.GoGitImplementation, "":
@@ -268,7 +275,7 @@ func (r *ImageUpdateAutomationReconciler) Reconcile(ctx context.Context, req ctr
 
 		gitClient, err = gogit.NewClient(tmp, authOpts, opts...)
 	default:
-		err = fmt.Errorf("failed to create git client; referred GitRepository has invalid implementation: %s", origin.Spec.GitImplementation)
+		err = fmt.Errorf("failed to create git client; referred GitRepository has invalid implementation: %s", gitImplementation)
 	}
 	if err != nil {
 		return failWithError(err)
@@ -423,6 +430,10 @@ func (r *ImageUpdateAutomationReconciler) SetupWithManager(mgr ctrl.Manager, opt
 		return err
 	}
 
+	if r.features == nil {
+		r.features = features.FeatureGates()
+	}
+
 	return ctrl.NewControllerManagedBy(mgr).
 		For(&imagev1.ImageUpdateAutomation{}, builder.WithPredicates(
 			predicate.Or(predicate.GenerationChangedPredicate{}, predicates.ReconcileRequestedPredicate{}))).

controllers/suite_test.go

@@ -35,6 +35,7 @@ import (
 	sourcev1 "github.com/fluxcd/source-controller/api/v1beta2"
 
 	imagev1 "github.com/fluxcd/image-automation-controller/api/v1beta1"
+	"github.com/fluxcd/image-automation-controller/internal/features"
 	// +kubebuilder:scaffold:imports
 )
 
@@ -60,19 +61,34 @@ func TestMain(m *testing.M) {
 	utilruntime.Must(sourcev1.AddToScheme(scheme.Scheme))
 	utilruntime.Must(imagev1.AddToScheme(scheme.Scheme))
 
+	if err := transport.InitManagedTransport(); err != nil {
+		panic(fmt.Sprintf("failed to initialize libgit2 managed transport: %v", err))
+	}
+
+	code := runTestsWithFeatures(m, nil)
+	if code != 0 {
+		fmt.Println("failed with default feature values")
+		os.Exit(code)
+	}
+
+	code = runTestsWithFeatures(m, map[string]bool{
+		features.ForceGoGitImplementation: false,
+	})
+
+	os.Exit(code)
+}
+
+func runTestsWithFeatures(m *testing.M, feats map[string]bool) int {
 	testEnv = testenv.New(testenv.WithCRDPath(
 		filepath.Join("..", "config", "crd", "bases"),
 		filepath.Join("testdata", "crds"),
 	))
 
-	if err := transport.InitManagedTransport(); err != nil {
-		panic(fmt.Sprintf("failed to initialize libgit2 managed transport: %v", err))
-	}
-
 	controllerName := "image-automation-controller"
 	if err := (&ImageUpdateAutomationReconciler{
 		Client:        testEnv,
 		EventRecorder: testEnv.GetEventRecorderFor(controllerName),
+		features:      feats,
 	}).SetupWithManager(testEnv, ImageUpdateAutomationReconcilerOptions{}); err != nil {
 		panic(fmt.Sprintf("failed to start ImageUpdateAutomationReconciler: %v", err))
 	}
@@ -92,7 +108,7 @@ func TestMain(m *testing.M) {
 		panic(fmt.Sprintf("failed to stop the test environment: %v", err))
 	}
 
-	os.Exit(code)
+	return code
 }
 
 // This provides a regression assurance for image-automation-controller/#339.

internal/features/features.go

@@ -25,12 +25,23 @@ const (
 	// GitForcePushBranch enables the use of "force push" when push branches
 	// are configured.
 	GitForcePushBranch = "GitForcePushBranch"
+
+	// ForceGoGitImplementation ignores the value set for gitImplementation
+	// of a GitRepository object and ensures that go-git is used for all git operations.
+	//
+	// When enabled, libgit2 won't be initialized, nor will any git2go cgo
+	// code be called.
+	ForceGoGitImplementation = "ForceGoGitImplementation"
 )
 
 var features = map[string]bool{
 	// GitForcePushBranch
 	// opt-out from v0.27
 	GitForcePushBranch: true,
+
+	// ForceGoGitImplementation
+	// opt-out from v0.27
+	ForceGoGitImplementation: true,
 }
 
 // DefaultFeatureGates contains a list of all supported feature gates and

main.go

@@ -163,9 +163,11 @@ func main() {
 	}
 	// +kubebuilder:scaffold:builder
 
-	if err = transport.InitManagedTransport(); err != nil {
-		setupLog.Error(err, "unable to initialize libgit2 managed transport")
-		os.Exit(1)
+	if gogitOnly, _ := features.Enabled(features.ForceGoGitImplementation); !gogitOnly {
+		if err = transport.InitManagedTransport(); err != nil {
+			setupLog.Error(err, "unable to initialize libgit2 managed transport")
+			os.Exit(1)
+		}
 	}
 
 	setupLog.Info("starting manager")