fix: Retry adding finalizers to referenced objects on conflict

internal/controller/object/object.go

@@ -799,18 +799,17 @@ func (f *objFinalizer) AddFinalizer(ctx context.Context, res resource.Object) er
 		return errors.New(errNotKubernetesObject)
 	}
 
-	if meta.FinalizerExists(obj, objFinalizerName) {
-		return nil
-	}
-	meta.AddFinalizer(obj, objFinalizerName)
+	if !meta.FinalizerExists(obj, objFinalizerName) {
+		meta.AddFinalizer(obj, objFinalizerName)
 
-	err := f.client.Update(ctx, obj)
-	if err != nil {
-		return errors.Wrap(err, errAddFinalizer)
+		err := f.client.Update(ctx, obj)
+		if err != nil {
+			return errors.Wrap(err, errAddFinalizer)
+		}
 	}
 
 	// Add finalizer to referenced resources if not exists
-	err = f.handleRefFinalizer(ctx, obj, func(
+	err := f.handleRefFinalizer(ctx, obj, func(
 		ctx context.Context, res *unstructured.Unstructured, finalizer string,
 	) error {
 		if !meta.FinalizerExists(res, finalizer) {

internal/controller/object/object_test.go

@@ -1066,6 +1066,32 @@ func TestAddFinalizer(t *testing.T) {
 				err: nil,
 			},
 		},
+		"SuccessfullyAddReferenceFinalizerOnRetry": {
+			args: args{
+				mg: kubernetesObject(func(obj *v1alpha2.Object) {
+					obj.ObjectMeta.Finalizers = append(obj.ObjectMeta.Finalizers, objFinalizerName)
+					obj.Spec.References = objectReferences()
+				}),
+				client: resource.ClientApplicator{
+					Client: &test.MockClient{
+						MockGet: test.NewMockGetFn(nil, func(obj client.Object) error {
+							*obj.(*unstructured.Unstructured) = *referenceObject()
+							return nil
+						}),
+						MockUpdate: test.NewMockUpdateFn(nil, func(obj client.Object) error {
+							name := obj.GetName()
+							if name == testReferenceObjectName {
+								return nil
+							}
+							return errBoom
+						}),
+					},
+				},
+			},
+			want: want{
+				err: nil,
+			},
+		},
 	}
 	for name, tc := range cases {
 		t.Run(name, func(t *testing.T) {