Clean up repo cache when repository is removed (#4049)

Signed-off-by: Morten Torkildsen <mortent@google.com>

porch/pkg/cache/repository.go

@@ -333,7 +333,7 @@ func (r *cachedRepository) Close() error {
 		}
 		r.objectNotifier.NotifyPackageRevisionChange(watch.Deleted, pr, pkgRevMeta)
 	}
-	return nil
+	return r.repo.Close()
 }
 
 // pollForever will continue polling until signal channel is closed or ctx is done.

porch/pkg/engine/fake/repository.go

@@ -30,6 +30,10 @@ type Repository struct {
 
 var _ repository.Repository = &Repository{}
 
+func (r *Repository) Close() error {
+	return nil
+}
+
 func (r *Repository) ListPackageRevisions(_ context.Context, filter repository.ListPackageRevisionFilter) ([]repository.PackageRevision, error) {
 	var revs []repository.PackageRevision
 	for _, rev := range r.PackageRevisions {

porch/pkg/git/git.go

@@ -131,6 +131,7 @@ func OpenRepository(ctx context.Context, name, namespace string, spec *configapi
 		secret:             spec.SecretRef.Name,
 		credentialResolver: opts.CredentialResolver,
 		userInfoProvider:   opts.UserInfoProvider,
+		cacheDir:           dir,
 		deployment:         deployment,
 	}
 
@@ -157,6 +158,9 @@ type gitRepository struct {
 	credentialResolver repository.CredentialResolver
 	userInfoProvider   repository.UserInfoProvider
 
+	// Folder used for the local git cache.
+	cacheDir string
+
 	// deployment holds spec.deployment
 	// TODO: Better caching here, support repository spec changes
 	deployment bool
@@ -175,6 +179,13 @@ type gitRepository struct {
 
 var _ GitRepository = &gitRepository{}
 
+func (r *gitRepository) Close() error {
+	if err := os.RemoveAll(r.cacheDir); err != nil {
+		return fmt.Errorf("error cleaning up local git cache for repo %s: %v", r.name, err)
+	}
+	return nil
+}
+
 func (r *gitRepository) ListPackages(ctx context.Context, filter repository.ListPackageFilter) ([]repository.Package, error) {
 	ctx, span := tracer.Start(ctx, "gitRepository::ListPackages", trace.WithAttributes())
 	defer span.End()

porch/pkg/oci/oci.go

@@ -63,6 +63,10 @@ type ociRepository struct {
 var _ repository.Repository = &ociRepository{}
 var _ repository.FunctionRepository = &ociRepository{}
 
+func (r *ociRepository) Close() error {
+	return nil
+}
+
 func (r *ociRepository) ListPackageRevisions(ctx context.Context, filter repository.ListPackageRevisionFilter) ([]repository.PackageRevision, error) {
 	if r.content != configapi.RepositoryContentPackage {
 		return []repository.PackageRevision{}, nil

porch/pkg/registry/porch/background.go

@@ -103,7 +103,9 @@ loop:
 					bookmark = repository.ResourceVersion
 					klog.Infof("Bookmark: %q", bookmark)
 				} else {
-					b.updateCache(ctx, event.Type, repository)
+					if err := b.updateCache(ctx, event.Type, repository); err != nil {
+						klog.Warningf("error updating cache: %v", err)
+					}
 				}
 			} else {
 				klog.V(5).Infof("Received unexpected watch event Object: %T", event.Object)
@@ -136,13 +138,52 @@ func (b *background) updateCache(ctx context.Context, event watch.EventType, rep
 		// TODO: implement
 	case watch.Deleted:
 		klog.Infof("Repository deleted: %s:%s", repository.ObjectMeta.Namespace, repository.ObjectMeta.Name)
-		return b.cache.CloseRepository(repository)
+		shared, err := b.isSharedRepository(ctx, repository)
+		if err != nil {
+			return err
+		}
+		// Only close the repository if no other k8s repository resources references
+		// the same underlying git/oci repo.
+		if !shared {
+			return b.cache.CloseRepository(repository)
+		}
+		return nil
 	default:
 		klog.Warning("Unhandled watch event type: %s", event)
 	}
 	return nil
 }
 
+// isSharedRepository checks if the underlying git/oci repo of the provided
+// k8s repository is also used by another repository.
+func (b *background) isSharedRepository(ctx context.Context, repo *configapi.Repository) (bool, error) {
+	var obj configapi.RepositoryList
+	if err := b.coreClient.List(ctx, &obj); err != nil {
+		return false, err
+	}
+	for _, r := range obj.Items {
+		if r.Name == repo.Name && r.Namespace == repo.Namespace {
+			continue
+		}
+		if r.Spec.Type != repo.Spec.Type {
+			continue
+		}
+		switch r.Spec.Type {
+		case configapi.RepositoryTypeOCI:
+			if r.Spec.Oci.Registry == repo.Spec.Oci.Registry {
+				return true, nil
+			}
+		case configapi.RepositoryTypeGit:
+			if r.Spec.Git.Repo == repo.Spec.Git.Repo {
+				return true, nil
+			}
+		default:
+			return false, fmt.Errorf("type %q not supported", r.Spec.Type)
+		}
+	}
+	return false, nil
+}
+
 func (b *background) runOnce(ctx context.Context) error {
 	klog.Infof("background-refreshing repositories")
 	var repositories configapi.RepositoryList

porch/pkg/repository/repository.go

@@ -202,6 +202,9 @@ type Repository interface {
 
 	// DeletePackage deletes a package
 	DeletePackage(ctx context.Context, old Package) error
+
+	// Close cleans up any resources associated with the repository
+	Close() error
 }
 
 type FunctionRepository interface {