Add a finalizer to the ImagePolicy and ImageRepository resources

Fixes #225

This PR adds a finalizer to the ImagePolicy and ImageRepository resources. This is to properly record the Deleted reconciliation status when the object is deleted from the cluster. Without this change, the resource would be deleted before the image reflector controller has a chance to properly report the resource's status in the metrics. As a result, end-users may see falsely reported metrics.

Signed-off-by: Kaden Nelson <[email protected]>

Author: kaden-l-nelson

api/v1beta1/imagepolicy_types.go

@@ -24,6 +24,7 @@ import (
 )
 
 const ImagePolicyKind = "ImagePolicy"
+const ImagePolicyFinalizer = "finalizers.fluxcd.io"
 
 // ImagePolicySpec defines the parameters for calculating the
 // ImagePolicy

api/v1beta1/imagerepository_types.go

@@ -27,6 +27,7 @@ import (
 )
 
 const ImageRepositoryKind = "ImageRepository"
+const ImageRepositoryFinalizer = "finalizers.fluxcd.io"
 
 // ImageRepositorySpec defines the parameters for scanning an image
 // repository, e.g., `fluxcd/flux`.

controllers/imagepolicy_controller.go

@@ -30,6 +30,7 @@ import (
 	ctrl "sigs.k8s.io/controller-runtime"
 	"sigs.k8s.io/controller-runtime/pkg/client"
 	"sigs.k8s.io/controller-runtime/pkg/controller"
+	"sigs.k8s.io/controller-runtime/pkg/controller/controllerutil"
 	"sigs.k8s.io/controller-runtime/pkg/handler"
 	"sigs.k8s.io/controller-runtime/pkg/reconcile"
 	"sigs.k8s.io/controller-runtime/pkg/source"
@@ -89,6 +90,26 @@ func (r *ImagePolicyReconciler) Reconcile(ctx context.Context, req ctrl.Request)
 	}
 	defer r.recordReadinessMetric(ctx, &pol)
 
+	// Add our finalizer if it does not exist.
+	if !controllerutil.ContainsFinalizer(&pol, imagev1.ImagePolicyFinalizer) {
+		patch := client.MergeFrom(pol.DeepCopy())
+		controllerutil.AddFinalizer(&pol, imagev1.ImagePolicyFinalizer)
+		if err := r.Patch(ctx, &pol, patch); err != nil {
+			log.Error(err, "unable to register finalizer")
+			return ctrl.Result{}, err
+		}
+	}
+
+	// If the object is under deletion, record the readiness, and remove our finalizer.
+	if !pol.ObjectMeta.DeletionTimestamp.IsZero() {
+		r.recordReadinessMetric(ctx, &pol)
+		controllerutil.RemoveFinalizer(&pol, imagev1.ImagePolicyFinalizer)
+		if err := r.Update(ctx, &pol); err != nil {
+			return ctrl.Result{}, err
+		}
+		return ctrl.Result{}, nil
+	}
+
 	var repo imagev1.ImageRepository
 	repoNamespacedName := types.NamespacedName{
 		Namespace: pol.Namespace,

controllers/imagerepository_controller.go

@@ -46,6 +46,7 @@ import (
 	ctrl "sigs.k8s.io/controller-runtime"
 	"sigs.k8s.io/controller-runtime/pkg/client"
 	"sigs.k8s.io/controller-runtime/pkg/controller"
+	"sigs.k8s.io/controller-runtime/pkg/controller/controllerutil"
 	"sigs.k8s.io/controller-runtime/pkg/predicate"
 
 	"github.com/Azure/azure-sdk-for-go/sdk/azcore/arm"
@@ -128,6 +129,26 @@ func (r *ImageRepositoryReconciler) Reconcile(ctx context.Context, req ctrl.Requ
 
 	log := ctrl.LoggerFrom(ctx)
 
+	// Add our finalizer if it does not exist.
+	if !controllerutil.ContainsFinalizer(&imageRepo, imagev1.ImageRepositoryFinalizer) {
+		patch := client.MergeFrom(imageRepo.DeepCopy())
+		controllerutil.AddFinalizer(&imageRepo, imagev1.ImageRepositoryFinalizer)
+		if err := r.Patch(ctx, &imageRepo, patch); err != nil {
+			log.Error(err, "unable to register finalizer")
+			return ctrl.Result{}, err
+		}
+	}
+
+	// If the object is under deletion, record the readiness, and remove our finalizer.
+	if !imageRepo.ObjectMeta.DeletionTimestamp.IsZero() {
+		r.recordReadinessMetric(ctx, &imageRepo)
+		controllerutil.RemoveFinalizer(&imageRepo, imagev1.ImageRepositoryFinalizer)
+		if err := r.Update(ctx, &imageRepo); err != nil {
+			return ctrl.Result{}, err
+		}
+		return ctrl.Result{}, nil
+	}
+
 	if imageRepo.Spec.Suspend {
 		msg := "ImageRepository is suspended, skipping reconciliation"
 		imagev1.SetImageRepositoryReadiness(