Fix deletion of resources with deleted CRDs (#778)

We don't have any yet, but when VPA is added, the reconciler-manager
cleanup will need to work with resources whos CRD may have been
removed. Also fix the errors so they can be unwrapped correctly.
This will fix error messages to be more clear.

pkg/reconcilermanager/controllers/errors.go

@@ -61,6 +61,12 @@ func (ooe *ObjectOperationError) Error() string {
 		ooe.ID.Kind, ooe.ID.ObjectKey, ooe.Operation, ooe.Cause)
 }
 
+// Unwrap returns the cause of the error, to allow type checking with errors.Is
+// and errors.As.
+func (ooe *ObjectOperationError) Unwrap() error {
+	return ooe.Cause
+}
+
 // NewObjectOperationError constructs a new ObjectOperationError
 func NewObjectOperationError(err error, obj client.Object, op Operation) *ObjectOperationError {
 	id := core.IDOf(obj)
@@ -144,6 +150,12 @@ func (oripe *ObjectReconcileError) Error() string {
 		oripe.ID.Kind, oripe.ID.ObjectKey, oripe.Status, oripe.Cause)
 }
 
+// Unwrap returns the cause of the error, to allow type checking with errors.Is
+// and errors.As.
+func (oripe *ObjectReconcileError) Unwrap() error {
+	return oripe.Cause
+}
+
 // NewObjectReconcileError constructs a new ObjectReconcileError
 func NewObjectReconcileError(err error, obj client.Object, status kstatus.Status) *ObjectReconcileError {
 	id := core.IDOf(obj)

pkg/util/watch/delete.go

@@ -20,6 +20,7 @@ import (
 
 	"github.com/pkg/errors"
 	apierrors "k8s.io/apimachinery/pkg/api/errors"
+	"k8s.io/apimachinery/pkg/api/meta"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/client-go/tools/cache"
 	"k8s.io/klog/v2"
@@ -166,6 +167,13 @@ func DeleteAndWait(ctx context.Context, c client.WithWatch, obj client.Object, r
 				// Stop waiting - object already deleted
 				return true, nil
 			}
+			if meta.IsNoMatchError(err) {
+				klog.V(3).Infof("Resource not registered %q=%q, %q=%q",
+					logFieldObjectRef, id.ObjectKey.String(),
+					logFieldObjectKind, id.Kind)
+				// Stop waiting - resource not registered
+				return true, nil
+			}
 			// Stop waiting
 			return false, err
 		}

pkg/util/watch/until.go

@@ -62,6 +62,15 @@ func UntilDeletedWithSync(ctx context.Context, c client.WithWatch, obj client.Ob
 	if err != nil {
 		return err
 	}
+	// Validate that the resource API is registered.
+	// If not, error and let the caller deal with whether NoMatchError is
+	// tolerated or not.
+	// Without this check, the informer will retry endlessly waiting for the
+	// ListAndWatch to succeed.
+	_, err = c.RESTMapper().RESTMapping(itemGVK.GroupKind(), itemGVK.Version)
+	if err != nil {
+		return err
+	}
 	var objList client.ObjectList
 	if _, ok := obj.(*unstructured.Unstructured); ok {
 		objList = kinds.NewUnstructuredListForItemGVK(itemGVK)