Remove workarounds for missing zeroing in json decoder

Now that the c-r client zeroes fields before decoding into the object,
we can drop our workarounds for this, so basically drop
kutil.CreateResetObjectFunc and its usages.

ref kubernetes-sigs/controller-runtime#1640

pkg/controllerutils/patch.go

@@ -18,8 +18,6 @@ import (
 	"context"
 	"reflect"
 
-	kutil "github.com/gardener/gardener/pkg/utils/kubernetes"
-
 	apierrors "k8s.io/apimachinery/pkg/api/errors"
 	"k8s.io/apimachinery/pkg/util/wait"
 	"sigs.k8s.io/controller-runtime/pkg/client"
@@ -108,16 +106,6 @@ func CreateOrGetAndStrategicMergePatch(ctx context.Context, c client.Client, obj
 }
 
 func createOrGetAndPatch(ctx context.Context, c client.Client, obj client.Object, patchFunc patchFn, f controllerutil.MutateFn) (controllerutil.OperationResult, error) {
-	var (
-		namespace = obj.GetNamespace()
-		name      = obj.GetName()
-	)
-
-	resetObj, err := kutil.CreateResetObjectFunc(obj, c.Scheme())
-	if err != nil {
-		return controllerutil.OperationResultNone, err
-	}
-
 	if err := f(); err != nil {
 		return controllerutil.OperationResultNone, err
 	}
@@ -127,16 +115,11 @@ func createOrGetAndPatch(ctx context.Context, c client.Client, obj client.Object
 			return controllerutil.OperationResultNone, err
 		}
 
-		resetObj()
-		obj.SetNamespace(namespace)
-		obj.SetName(name)
-
 		if err2 := c.Get(ctx, client.ObjectKeyFromObject(obj), obj); err2 != nil {
 			return controllerutil.OperationResultNone, err2
 		}
 
 		patch := patchFunc(obj.DeepCopyObject().(client.Object))
-
 		if err2 := f(); err2 != nil {
 			return controllerutil.OperationResultNone, err2
 		}

pkg/controllerutils/patch_test.go

@@ -214,8 +214,6 @@ var _ = Describe("Patch", func() {
 				gomock.InOrder(
 					c.EXPECT().Create(ctx, obj).Return(apierrors.NewAlreadyExists(schema.GroupResource{}, "")),
 					c.EXPECT().Get(ctx, client.ObjectKeyFromObject(obj), obj).DoAndReturn(func(_ context.Context, _ client.ObjectKey, objToReturn *corev1.ServiceAccount) error {
-						Expect(obj.GetLabels()).To(BeEmpty(), "object should be reset before getting it again")
-
 						obj.DeepCopyInto(objToReturn)
 						return nil
 					}),

pkg/extensions/customresources.go

@@ -93,17 +93,9 @@ func WaitUntilObjectReadyWithHealthFunction(
 		healthFunc = health.And(health.ObjectHasAnnotationWithValue(v1beta1constants.GardenerTimestamp, expectedTimestamp), healthFunc)
 	}
 
-	resetObj, err := kutil.CreateResetObjectFunc(obj, c.Scheme())
-	if err != nil {
-		return err
-	}
-
 	if err := retry.UntilTimeout(ctx, interval, timeout, func(ctx context.Context) (bool, error) {
 		retryCountUntilSevere++
 
-		resetObj()
-		obj.SetName(name)
-		obj.SetNamespace(namespace)
 		if err := c.Get(ctx, client.ObjectKeyFromObject(obj), obj); err != nil {
 			if apierrors.IsNotFound(err) {
 				return retry.MinorError(err)
@@ -221,15 +213,7 @@ func WaitUntilExtensionObjectDeleted(
 		namespace = obj.GetNamespace()
 	)
 
-	resetObj, err := kutil.CreateResetObjectFunc(obj, c.Scheme())
-	if err != nil {
-		return err
-	}
-
 	if err := retry.UntilTimeout(ctx, interval, timeout, func(ctx context.Context) (bool, error) {
-		resetObj()
-		obj.SetName(name)
-		obj.SetNamespace(namespace)
 		if err := c.Get(ctx, client.ObjectKeyFromObject(obj), obj); err != nil {
 			if apierrors.IsNotFound(err) {
 				return retry.Ok()
@@ -363,20 +347,7 @@ func WaitUntilExtensionObjectMigrated(
 	interval time.Duration,
 	timeout time.Duration,
 ) error {
-	var (
-		name      = obj.GetName()
-		namespace = obj.GetNamespace()
-	)
-
-	resetObj, err := kutil.CreateResetObjectFunc(obj, c.Scheme())
-	if err != nil {
-		return err
-	}
-
 	return retry.UntilTimeout(ctx, interval, timeout, func(ctx context.Context) (done bool, err error) {
-		resetObj()
-		obj.SetName(name)
-		obj.SetNamespace(namespace)
 		if err := c.Get(ctx, client.ObjectKeyFromObject(obj), obj); err != nil {
 			if client.IgnoreNotFound(err) == nil {
 				return retry.Ok()
@@ -396,7 +367,7 @@ func WaitUntilExtensionObjectMigrated(
 		if extensionSpec := obj.GetExtensionSpec(); extensionSpec != nil {
 			extensionType = extensionSpec.GetExtensionType()
 		}
-		return retry.MinorError(fmt.Errorf("lastOperation for %s with name %s and type %s is not Migrate=Succeeded", obj.GetObjectKind().GroupVersionKind().Kind, name, extensionType))
+		return retry.MinorError(fmt.Errorf("lastOperation for %s with name %s and type %s is not Migrate=Succeeded", obj.GetObjectKind().GroupVersionKind().Kind, obj.GetName(), extensionType))
 	})
 }
 

pkg/utils/kubernetes/object.go

@@ -17,19 +17,17 @@ package kubernetes
 import (
 	"context"
 	"fmt"
-	"reflect"
 	"strings"
 
-	"github.com/gardener/gardener/pkg/resourcemanager/controller/garbagecollector/references"
 	corev1 "k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/api/meta"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/apimachinery/pkg/runtime/schema"
 	"k8s.io/utils/pointer"
 	"sigs.k8s.io/controller-runtime/pkg/client"
-	"sigs.k8s.io/controller-runtime/pkg/client/apiutil"
 
+	"github.com/gardener/gardener/pkg/resourcemanager/controller/garbagecollector/references"
 	"github.com/gardener/gardener/pkg/utils"
 	"github.com/gardener/gardener/pkg/utils/flow"
 )
@@ -91,31 +89,6 @@ func IsNamespaceInUse(ctx context.Context, reader client.Reader, namespace strin
 	return len(objects.Items) > 0, nil
 }
 
-// CreateResetObjectFunc creates a func that will reset the given object to a new empty object every time the func is called.
-// This is useful for resetting an in-memory object before re-getting it from the API server / cache
-// to avoid executing checks on stale/removed object data e.g. annotations/lastError
-// (json decoder does not unset fields in the in-memory object that are unset in the API server's response)
-func CreateResetObjectFunc(obj runtime.Object, scheme *runtime.Scheme) (func(), error) {
-	gvk, err := apiutil.GVKForObject(obj, scheme)
-	if err != nil {
-		return nil, err
-	}
-	emptyObj, err := scheme.New(gvk)
-	if err != nil {
-		return nil, err
-	}
-	return func() {
-		deepCopyIntoObject(obj, emptyObj)
-	}, nil
-}
-
-// deepCopyIntoObject deep copies src into dest.
-// This is a workaround for runtime.Object's lack of a DeepCopyInto method, similar to what the c-r cache does:
-// https://github.com/kubernetes-sigs/controller-runtime/blob/55a329c15d6b4f91a9ff072fed6f6f05ff3339e7/pkg/cache/internal/cache_reader.go#L85-L90
-func deepCopyIntoObject(dest, src runtime.Object) {
-	reflect.ValueOf(dest).Elem().Set(reflect.ValueOf(src.DeepCopyObject()).Elem())
-}
-
 // MakeUnique takes either a *corev1.ConfigMap or a *corev1.Secret object and makes it immutable, i.e., it sets
 // .immutable=true, computes a checksum based on .data, and appends the first 8 characters of the computed checksum
 // to the name of the object. Additionally, it injects the `resources.gardener.cloud/garbage-collectable-reference=true`

pkg/utils/kubernetes/object_test.go

@@ -179,36 +179,6 @@ var _ = Describe("Object", func() {
 		})
 	})
 
-	Describe("#CreateResetObjectFunc", func() {
-		var (
-			obj = &corev1.ServiceAccount{
-				ObjectMeta: metav1.ObjectMeta{
-					Name: "non-empty-sa",
-				},
-			}
-			objCopy = obj.DeepCopy()
-		)
-
-		It("should fail because the GVK for the object cannot be determined", func() {
-			f, err := CreateResetObjectFunc(obj, runtime.NewScheme())
-			Expect(f).To(BeNil())
-			Expect(runtime.IsNotRegisteredError(err)).To(BeTrue())
-			Expect(obj).To(Equal(objCopy))
-		})
-
-		It("should return a function that allows resets an object", func() {
-			scheme := runtime.NewScheme()
-			Expect(corev1.AddToScheme(scheme)).To(Succeed())
-
-			f, err := CreateResetObjectFunc(obj, scheme)
-			Expect(f).NotTo(BeNil())
-			Expect(err).NotTo(HaveOccurred())
-
-			f()
-			Expect(obj).To(Equal(&corev1.ServiceAccount{}))
-		})
-	})
-
 	Describe("#MakeUnique", func() {
 		var (
 			name                 = "some-name"