Merge pull request #25018 from smarterclayton/fast_conversion

pkg/api/conversion_test.go

@@ -50,11 +50,11 @@ func BenchmarkPodConversion(b *testing.B) {
 	var result *api.Pod
 	for i := 0; i < b.N; i++ {
 		pod := &items[i%width]
-		versionedObj, err := scheme.ConvertToVersion(pod, testapi.Default.GroupVersion().String())
+		versionedObj, err := scheme.UnsafeConvertToVersion(pod, *testapi.Default.GroupVersion())
 		if err != nil {
 			b.Fatalf("Conversion error: %v", err)
 		}
-		obj, err := scheme.ConvertToVersion(versionedObj, testapi.Default.InternalGroupVersion().String())
+		obj, err := scheme.UnsafeConvertToVersion(versionedObj, testapi.Default.InternalGroupVersion())
 		if err != nil {
 			b.Fatalf("Conversion error: %v", err)
 		}
@@ -76,11 +76,11 @@ func BenchmarkNodeConversion(b *testing.B) {
 	scheme := api.Scheme
 	var result *api.Node
 	for i := 0; i < b.N; i++ {
-		versionedObj, err := scheme.ConvertToVersion(&node, testapi.Default.GroupVersion().String())
+		versionedObj, err := scheme.UnsafeConvertToVersion(&node, *testapi.Default.GroupVersion())
 		if err != nil {
 			b.Fatalf("Conversion error: %v", err)
 		}
-		obj, err := scheme.ConvertToVersion(versionedObj, testapi.Default.InternalGroupVersion().String())
+		obj, err := scheme.UnsafeConvertToVersion(versionedObj, testapi.Default.InternalGroupVersion())
 		if err != nil {
 			b.Fatalf("Conversion error: %v", err)
 		}
@@ -104,11 +104,11 @@ func BenchmarkReplicationControllerConversion(b *testing.B) {
 	scheme := api.Scheme
 	var result *api.ReplicationController
 	for i := 0; i < b.N; i++ {
-		versionedObj, err := scheme.ConvertToVersion(&replicationController, testapi.Default.GroupVersion().String())
+		versionedObj, err := scheme.UnsafeConvertToVersion(&replicationController, *testapi.Default.GroupVersion())
 		if err != nil {
 			b.Fatalf("Conversion error: %v", err)
 		}
-		obj, err := scheme.ConvertToVersion(versionedObj, testapi.Default.InternalGroupVersion().String())
+		obj, err := scheme.UnsafeConvertToVersion(versionedObj, testapi.Default.InternalGroupVersion())
 		if err != nil {
 			b.Fatalf("Conversion error: %v", err)
 		}

pkg/api/meta/meta.go

@@ -123,33 +123,21 @@ type objectAccessor struct {
 }
 
 func (obj objectAccessor) GetKind() string {
-	if gvk := obj.GetObjectKind().GroupVersionKind(); gvk != nil {
-		return gvk.Kind
-	}
-	return ""
+	return obj.GetObjectKind().GroupVersionKind().Kind
 }
 
 func (obj objectAccessor) SetKind(kind string) {
 	gvk := obj.GetObjectKind().GroupVersionKind()
-	if gvk == nil {
-		gvk = &unversioned.GroupVersionKind{}
-	}
 	gvk.Kind = kind
 	obj.GetObjectKind().SetGroupVersionKind(gvk)
 }
 
 func (obj objectAccessor) GetAPIVersion() string {
-	if gvk := obj.GetObjectKind().GroupVersionKind(); gvk != nil {
-		return gvk.GroupVersion().String()
-	}
-	return ""
+	return obj.GetObjectKind().GroupVersionKind().GroupVersion().String()
 }
 
 func (obj objectAccessor) SetAPIVersion(version string) {
 	gvk := obj.GetObjectKind().GroupVersionKind()
-	if gvk == nil {
-		gvk = &unversioned.GroupVersionKind{}
-	}
 	gv, err := unversioned.ParseGroupVersion(version)
 	if err != nil {
 		gv = unversioned.GroupVersion{Version: version}

pkg/api/meta/meta_test.go

@@ -253,10 +253,10 @@ type InternalObject struct {
 }
 
 func (obj *InternalObject) GetObjectKind() unversioned.ObjectKind { return obj }
-func (obj *InternalObject) SetGroupVersionKind(gvk *unversioned.GroupVersionKind) {
+func (obj *InternalObject) SetGroupVersionKind(gvk unversioned.GroupVersionKind) {
 	obj.TypeMeta.APIVersion, obj.TypeMeta.Kind = gvk.ToAPIVersionAndKind()
 }
-func (obj *InternalObject) GroupVersionKind() *unversioned.GroupVersionKind {
+func (obj *InternalObject) GroupVersionKind() unversioned.GroupVersionKind {
 	return unversioned.FromAPIVersionAndKind(obj.TypeMeta.APIVersion, obj.TypeMeta.Kind)
 }
 
@@ -610,10 +610,10 @@ type MyAPIObject struct {
 }
 
 func (obj *MyAPIObject) GetObjectKind() unversioned.ObjectKind { return obj }
-func (obj *MyAPIObject) SetGroupVersionKind(gvk *unversioned.GroupVersionKind) {
+func (obj *MyAPIObject) SetGroupVersionKind(gvk unversioned.GroupVersionKind) {
 	obj.TypeMeta.APIVersion, obj.TypeMeta.Kind = gvk.ToAPIVersionAndKind()
 }
-func (obj *MyAPIObject) GroupVersionKind() *unversioned.GroupVersionKind {
+func (obj *MyAPIObject) GroupVersionKind() unversioned.GroupVersionKind {
 	return unversioned.FromAPIVersionAndKind(obj.TypeMeta.APIVersion, obj.TypeMeta.Kind)
 }
 

pkg/api/meta/restmapper_test.go

@@ -32,7 +32,7 @@ func (fakeConvertor) Convert(in, out interface{}) error {
 	return nil
 }
 
-func (fakeConvertor) ConvertToVersion(in runtime.Object, _ string) (runtime.Object, error) {
+func (fakeConvertor) ConvertToVersion(in runtime.Object, _ unversioned.GroupVersion) (runtime.Object, error) {
 	return in, nil
 }
 

pkg/api/ref.go

@@ -54,10 +54,7 @@ func GetReference(obj runtime.Object) (*ObjectReference, error) {
 
 	// if the object referenced is actually persisted, we can just get kind from meta
 	// if we are building an object reference to something not yet persisted, we should fallback to scheme
-	var kind string
-	if gvk != nil {
-		kind = gvk.Kind
-	}
+	kind := gvk.Kind
 	if len(kind) == 0 {
 		// TODO: this is wrong
 		gvk, err := Scheme.ObjectKind(obj)
@@ -68,10 +65,7 @@ func GetReference(obj runtime.Object) (*ObjectReference, error) {
 	}
 
 	// if the object referenced is actually persisted, we can also get version from meta
-	var version string
-	if gvk != nil {
-		version = gvk.GroupVersion().String()
-	}
+	version := gvk.GroupVersion().String()
 	if len(version) == 0 {
 		selfLink := meta.GetSelfLink()
 		if len(selfLink) == 0 {
@@ -111,9 +105,9 @@ func GetPartialReference(obj runtime.Object, fieldPath string) (*ObjectReference
 
 // IsAnAPIObject allows clients to preemptively get a reference to an API object and pass it to places that
 // intend only to get a reference to that object. This simplifies the event recording interface.
-func (obj *ObjectReference) SetGroupVersionKind(gvk *unversioned.GroupVersionKind) {
+func (obj *ObjectReference) SetGroupVersionKind(gvk unversioned.GroupVersionKind) {
 	obj.APIVersion, obj.Kind = gvk.ToAPIVersionAndKind()
 }
-func (obj *ObjectReference) GroupVersionKind() *unversioned.GroupVersionKind {
+func (obj *ObjectReference) GroupVersionKind() unversioned.GroupVersionKind {
 	return unversioned.FromAPIVersionAndKind(obj.APIVersion, obj.Kind)
 }

pkg/api/serialization_test.go

@@ -281,7 +281,7 @@ func TestObjectWatchFraming(t *testing.T) {
 	secret.Data["binary"] = []byte{0x00, 0x10, 0x30, 0x55, 0xff, 0x00}
 	secret.Data["utf8"] = []byte("a string with \u0345 characters")
 	secret.Data["long"] = bytes.Repeat([]byte{0x01, 0x02, 0x03, 0x00}, 1000)
-	converted, _ := api.Scheme.ConvertToVersion(secret, "v1")
+	converted, _ := api.Scheme.ConvertToVersion(secret, v1.SchemeGroupVersion)
 	v1secret := converted.(*v1.Secret)
 	for _, streamingMediaType := range api.Codecs.SupportedStreamingMediaTypes() {
 		s, _ := api.Codecs.StreamingSerializerForMediaType(streamingMediaType, nil)
@@ -358,7 +358,7 @@ func benchmarkItems() []v1.Pod {
 	for i := range items {
 		var pod api.Pod
 		apiObjectFuzzer.Fuzz(&pod)
-		out, err := api.Scheme.ConvertToVersion(&pod, "v1")
+		out, err := api.Scheme.ConvertToVersion(&pod, v1.SchemeGroupVersion)
 		if err != nil {
 			panic(err)
 		}

pkg/api/unversioned/group_version.go

@@ -259,11 +259,11 @@ func (gvk *GroupVersionKind) ToAPIVersionAndKind() (string, string) {
 // do not use TypeMeta. This method exists to support test types and legacy serializations
 // that have a distinct group and kind.
 // TODO: further reduce usage of this method.
-func FromAPIVersionAndKind(apiVersion, kind string) *GroupVersionKind {
+func FromAPIVersionAndKind(apiVersion, kind string) GroupVersionKind {
 	if gv, err := ParseGroupVersion(apiVersion); err == nil {
-		return &GroupVersionKind{Group: gv.Group, Version: gv.Version, Kind: kind}
+		return GroupVersionKind{Group: gv.Group, Version: gv.Version, Kind: kind}
 	}
-	return &GroupVersionKind{Kind: kind}
+	return GroupVersionKind{Kind: kind}
 }
 
 // All objects that are serialized from a Scheme encode their type information. This interface is used
@@ -273,10 +273,10 @@ func FromAPIVersionAndKind(apiVersion, kind string) *GroupVersionKind {
 type ObjectKind interface {
 	// SetGroupVersionKind sets or clears the intended serialized kind of an object. Passing kind nil
 	// should clear the current setting.
-	SetGroupVersionKind(kind *GroupVersionKind)
+	SetGroupVersionKind(kind GroupVersionKind)
 	// GroupVersionKind returns the stored group, version, and kind of an object, or nil if the object does
 	// not expose or provide these fields.
-	GroupVersionKind() *GroupVersionKind
+	GroupVersionKind() GroupVersionKind
 }
 
 // EmptyObjectKind implements the ObjectKind interface as a noop
@@ -286,7 +286,7 @@ var EmptyObjectKind = emptyObjectKind{}
 type emptyObjectKind struct{}
 
 // SetGroupVersionKind implements the ObjectKind interface
-func (emptyObjectKind) SetGroupVersionKind(gvk *GroupVersionKind) {}
+func (emptyObjectKind) SetGroupVersionKind(gvk GroupVersionKind) {}
 
 // GroupVersionKind implements the ObjectKind interface
-func (emptyObjectKind) GroupVersionKind() *GroupVersionKind { return nil }
+func (emptyObjectKind) GroupVersionKind() GroupVersionKind { return GroupVersionKind{} }

pkg/api/unversioned/register.go

@@ -25,12 +25,12 @@ func Kind(kind string) GroupKind {
 }
 
 // SetGroupVersionKind satisfies the ObjectKind interface for all objects that embed TypeMeta
-func (obj *TypeMeta) SetGroupVersionKind(gvk *GroupVersionKind) {
+func (obj *TypeMeta) SetGroupVersionKind(gvk GroupVersionKind) {
 	obj.APIVersion, obj.Kind = gvk.ToAPIVersionAndKind()
 }
 
 // GroupVersionKind satisfies the ObjectKind interface for all objects that embed TypeMeta
-func (obj *TypeMeta) GroupVersionKind() *GroupVersionKind {
+func (obj *TypeMeta) GroupVersionKind() GroupVersionKind {
 	return FromAPIVersionAndKind(obj.APIVersion, obj.Kind)
 }
 

pkg/api/validation/validation.go

@@ -149,7 +149,7 @@ func validateOwnerReference(ownerReference api.OwnerReference, fldPath *field.Pa
 	if len(ownerReference.UID) == 0 {
 		allErrs = append(allErrs, field.Invalid(fldPath.Child("uid"), ownerReference.UID, "uid must not be empty"))
 	}
-	if _, ok := BannedOwners[*gvk]; ok {
+	if _, ok := BannedOwners[gvk]; ok {
 		allErrs = append(allErrs, field.Invalid(fldPath, ownerReference, fmt.Sprintf("%s is disallowed from being an owner", gvk)))
 	}
 	return allErrs

pkg/apiserver/apiserver.go

@@ -264,7 +264,7 @@ func (c stripVersionEncoder) EncodeToStream(obj runtime.Object, w io.Writer, ove
 	}
 	gvk.Group = ""
 	gvk.Version = ""
-	roundTrippedObj.GetObjectKind().SetGroupVersionKind(gvk)
+	roundTrippedObj.GetObjectKind().SetGroupVersionKind(*gvk)
 	return c.serializer.EncodeToStream(roundTrippedObj, w)
 }
 

pkg/apiserver/resthandler.go

@@ -459,7 +459,7 @@ func PatchResource(r rest.Patcher, scope RequestScope, typer runtime.ObjectTyper
 		ctx := scope.ContextFunc(req)
 		ctx = api.WithNamespace(ctx, namespace)
 
-		versionedObj, err := converter.ConvertToVersion(r.New(), scope.Kind.GroupVersion().String())
+		versionedObj, err := converter.ConvertToVersion(r.New(), scope.Kind.GroupVersion())
 		if err != nil {
 			scope.err(err, res.ResponseWriter, req.Request)
 			return

pkg/apiserver/resthandler_test.go

@@ -174,7 +174,7 @@ func (tc *patchTestCase) Run(t *testing.T) {
 
 	namer := &testNamer{namespace, name}
 
-	versionedObj, err := api.Scheme.ConvertToVersion(&api.Pod{}, "v1")
+	versionedObj, err := api.Scheme.ConvertToVersion(&api.Pod{}, unversioned.GroupVersion{Version: "v1"})
 	if err != nil {
 		t.Errorf("%s: unexpected error: %v", tc.name, err)
 		return

pkg/client/unversioned/clientcmd/api/register.go

@@ -35,9 +35,9 @@ func init() {
 }
 
 func (obj *Config) GetObjectKind() unversioned.ObjectKind { return obj }
-func (obj *Config) SetGroupVersionKind(gvk *unversioned.GroupVersionKind) {
+func (obj *Config) SetGroupVersionKind(gvk unversioned.GroupVersionKind) {
 	obj.APIVersion, obj.Kind = gvk.ToAPIVersionAndKind()
 }
-func (obj *Config) GroupVersionKind() *unversioned.GroupVersionKind {
+func (obj *Config) GroupVersionKind() unversioned.GroupVersionKind {
 	return unversioned.FromAPIVersionAndKind(obj.APIVersion, obj.Kind)
 }

pkg/client/unversioned/clientcmd/api/v1/register.go

@@ -32,9 +32,9 @@ func init() {
 }
 
 func (obj *Config) GetObjectKind() unversioned.ObjectKind { return obj }
-func (obj *Config) SetGroupVersionKind(gvk *unversioned.GroupVersionKind) {
+func (obj *Config) SetGroupVersionKind(gvk unversioned.GroupVersionKind) {
 	obj.APIVersion, obj.Kind = gvk.ToAPIVersionAndKind()
 }
-func (obj *Config) GroupVersionKind() *unversioned.GroupVersionKind {
+func (obj *Config) GroupVersionKind() unversioned.GroupVersionKind {
 	return unversioned.FromAPIVersionAndKind(obj.APIVersion, obj.Kind)
 }

pkg/conversion/converter.go

@@ -210,9 +210,6 @@ func (c ConversionFuncs) Merge(other ConversionFuncs) ConversionFuncs {
 
 // Meta is supplied by Scheme, when it calls Convert.
 type Meta struct {
-	SrcVersion  string
-	DestVersion string
-
 	// KeyNameMapping is an optional function which may map the listed key (field name)
 	// into a source and destination value.
 	KeyNameMapping FieldMappingFunc

pkg/conversion/converter_test.go

@@ -611,7 +611,7 @@ func TestConverter_meta(t *testing.T) {
 	checks := 0
 	err := c.RegisterConversionFunc(
 		func(in *Foo, out *Bar, s Scope) error {
-			if s.Meta() == nil || s.Meta().SrcVersion != "test" || s.Meta().DestVersion != "passes" {
+			if s.Meta() == nil {
 				t.Errorf("Meta did not get passed!")
 			}
 			checks++
@@ -624,7 +624,7 @@ func TestConverter_meta(t *testing.T) {
 	}
 	err = c.RegisterConversionFunc(
 		func(in *string, out *string, s Scope) error {
-			if s.Meta() == nil || s.Meta().SrcVersion != "test" || s.Meta().DestVersion != "passes" {
+			if s.Meta() == nil {
 				t.Errorf("Meta did not get passed a second time!")
 			}
 			checks++
@@ -634,7 +634,7 @@ func TestConverter_meta(t *testing.T) {
 	if err != nil {
 		t.Fatalf("Unexpected error: %v", err)
 	}
-	err = c.Convert(&Foo{}, &Bar{}, 0, &Meta{SrcVersion: "test", DestVersion: "passes"})
+	err = c.Convert(&Foo{}, &Bar{}, 0, &Meta{})
 	if err != nil {
 		t.Fatalf("Unexpected error: %v", err)
 	}

pkg/conversion/deep_copy_generated.go

@@ -174,8 +174,6 @@ func DeepCopy_conversion_Equalities(in Equalities, out *Equalities, c *Cloner) e
 }
 
 func DeepCopy_conversion_Meta(in Meta, out *Meta, c *Cloner) error {
-	out.SrcVersion = in.SrcVersion
-	out.DestVersion = in.DestVersion
 	if in.KeyNameMapping == nil {
 		out.KeyNameMapping = nil
 	} else if newVal, err := c.DeepCopy(in.KeyNameMapping); err != nil {

pkg/kubectl/cmd/annotate.go

@@ -221,7 +221,7 @@ func (o AnnotateOptions) RunAnnotate() error {
 			return err
 		}
 
-		obj, err := info.Mapping.ConvertToVersion(info.Object, info.Mapping.GroupVersionKind.GroupVersion().String())
+		obj, err := info.Mapping.ConvertToVersion(info.Object, info.Mapping.GroupVersionKind.GroupVersion())
 		if err != nil {
 			return err
 		}

pkg/kubectl/cmd/cmd_test.go

@@ -87,24 +87,24 @@ type ExternalType2 struct {
 }
 
 func (obj *internalType) GetObjectKind() unversioned.ObjectKind { return obj }
-func (obj *internalType) SetGroupVersionKind(gvk *unversioned.GroupVersionKind) {
+func (obj *internalType) SetGroupVersionKind(gvk unversioned.GroupVersionKind) {
 	obj.APIVersion, obj.Kind = gvk.ToAPIVersionAndKind()
 }
-func (obj *internalType) GroupVersionKind() *unversioned.GroupVersionKind {
+func (obj *internalType) GroupVersionKind() unversioned.GroupVersionKind {
 	return unversioned.FromAPIVersionAndKind(obj.APIVersion, obj.Kind)
 }
 func (obj *externalType) GetObjectKind() unversioned.ObjectKind { return obj }
-func (obj *externalType) SetGroupVersionKind(gvk *unversioned.GroupVersionKind) {
+func (obj *externalType) SetGroupVersionKind(gvk unversioned.GroupVersionKind) {
 	obj.APIVersion, obj.Kind = gvk.ToAPIVersionAndKind()
 }
-func (obj *externalType) GroupVersionKind() *unversioned.GroupVersionKind {
+func (obj *externalType) GroupVersionKind() unversioned.GroupVersionKind {
 	return unversioned.FromAPIVersionAndKind(obj.APIVersion, obj.Kind)
 }
 func (obj *ExternalType2) GetObjectKind() unversioned.ObjectKind { return obj }
-func (obj *ExternalType2) SetGroupVersionKind(gvk *unversioned.GroupVersionKind) {
+func (obj *ExternalType2) SetGroupVersionKind(gvk unversioned.GroupVersionKind) {
 	obj.APIVersion, obj.Kind = gvk.ToAPIVersionAndKind()
 }
-func (obj *ExternalType2) GroupVersionKind() *unversioned.GroupVersionKind {
+func (obj *ExternalType2) GroupVersionKind() unversioned.GroupVersionKind {
 	return unversioned.FromAPIVersionAndKind(obj.APIVersion, obj.Kind)
 }
 

pkg/kubectl/cmd/convert.go

@@ -167,7 +167,7 @@ func (o *ConvertOptions) RunConvert() error {
 		}
 
 		infos := []*resource.Info{info}
-		objects, err := resource.AsVersionedObject(infos, false, o.outputVersion.String(), o.encoder)
+		objects, err := resource.AsVersionedObject(infos, false, o.outputVersion, o.encoder)
 		if err != nil {
 			return err
 		}

pkg/kubectl/cmd/edit.go

@@ -182,7 +182,7 @@ func RunEdit(f *cmdutil.Factory, out, errOut io.Writer, cmd *cobra.Command, args
 	if err != nil {
 		return err
 	}
-	objs, err := resource.AsVersionedObjects(infos, defaultVersion.String(), encoder)
+	objs, err := resource.AsVersionedObjects(infos, defaultVersion, encoder)
 	if err != nil {
 		return err
 	}

pkg/kubectl/cmd/get.go

@@ -246,7 +246,7 @@ func RunGet(f *cmdutil.Factory, out io.Writer, cmd *cobra.Command, args []string
 		if err != nil {
 			return err
 		}
-		obj, err := resource.AsVersionedObject(infos, !singular, version.String(), f.JSONEncoder())
+		obj, err := resource.AsVersionedObject(infos, !singular, version, f.JSONEncoder())
 		if err != nil {
 			return err
 		}
@@ -273,7 +273,7 @@ func RunGet(f *cmdutil.Factory, out io.Writer, cmd *cobra.Command, args []string
 		}
 
 		for ix := range infos {
-			objs[ix], err = infos[ix].Mapping.ConvertToVersion(infos[ix].Object, version.String())
+			objs[ix], err = infos[ix].Mapping.ConvertToVersion(infos[ix].Object, version)
 			if err != nil {
 				allErrs = append(allErrs, err)
 				continue

pkg/kubectl/cmd/label.go

@@ -246,7 +246,7 @@ func RunLabel(f *cmdutil.Factory, out io.Writer, cmd *cobra.Command, args []stri
 			}
 			outputObj = info.Object
 		} else {
-			obj, err := info.Mapping.ConvertToVersion(info.Object, info.Mapping.GroupVersionKind.GroupVersion().String())
+			obj, err := info.Mapping.ConvertToVersion(info.Object, info.Mapping.GroupVersionKind.GroupVersion())
 			if err != nil {
 				return err
 			}

pkg/kubectl/resource/result.go

@@ -211,7 +211,7 @@ func (r *Result) Watch(resourceVersion string) (watch.Interface, error) {
 // the objects as children, or if only a single Object is present, as that object. The provided
 // version will be preferred as the conversion target, but the Object's mapping version will be
 // used if that version is not present.
-func AsVersionedObject(infos []*Info, forceList bool, version string, encoder runtime.Encoder) (runtime.Object, error) {
+func AsVersionedObject(infos []*Info, forceList bool, version unversioned.GroupVersion, encoder runtime.Encoder) (runtime.Object, error) {
 	objects, err := AsVersionedObjects(infos, version, encoder)
 	if err != nil {
 		return nil, err
@@ -222,7 +222,7 @@ func AsVersionedObject(infos []*Info, forceList bool, version string, encoder ru
 		object = objects[0]
 	} else {
 		object = &api.List{Items: objects}
-		converted, err := tryConvert(api.Scheme, object, version, registered.GroupOrDie(api.GroupName).GroupVersion.Version)
+		converted, err := tryConvert(api.Scheme, object, version, registered.GroupOrDie(api.GroupName).GroupVersion)
 		if err != nil {
 			return nil, err
 		}
@@ -234,7 +234,7 @@ func AsVersionedObject(infos []*Info, forceList bool, version string, encoder ru
 // AsVersionedObjects converts a list of infos into versioned objects. The provided
 // version will be preferred as the conversion target, but the Object's mapping version will be
 // used if that version is not present.
-func AsVersionedObjects(infos []*Info, version string, encoder runtime.Encoder) ([]runtime.Object, error) {
+func AsVersionedObjects(infos []*Info, version unversioned.GroupVersion, encoder runtime.Encoder) ([]runtime.Object, error) {
 	objects := []runtime.Object{}
 	for _, info := range infos {
 		if info.Object == nil {
@@ -250,7 +250,7 @@ func AsVersionedObjects(infos []*Info, version string, encoder runtime.Encoder)
 
 		// objects that are not part of api.Scheme must be converted to JSON
 		// TODO: convert to map[string]interface{}, attach to runtime.Unknown?
-		if len(version) > 0 {
+		if !version.IsEmpty() {
 			if _, err := api.Scheme.ObjectKind(info.Object); runtime.IsNotRegisteredError(err) {
 				// TODO: ideally this would encode to version, but we don't expose multiple codecs here.
 				data, err := runtime.Encode(encoder, info.Object)
@@ -263,7 +263,7 @@ func AsVersionedObjects(infos []*Info, version string, encoder runtime.Encoder)
 			}
 		}
 
-		converted, err := tryConvert(info.Mapping.ObjectConvertor, info.Object, version, info.Mapping.GroupVersionKind.GroupVersion().String())
+		converted, err := tryConvert(info.Mapping.ObjectConvertor, info.Object, version, info.Mapping.GroupVersionKind.GroupVersion())
 		if err != nil {
 			return nil, err
 		}
@@ -274,10 +274,10 @@ func AsVersionedObjects(infos []*Info, version string, encoder runtime.Encoder)
 
 // tryConvert attempts to convert the given object to the provided versions in order. This function assumes
 // the object is in internal version.
-func tryConvert(convertor runtime.ObjectConvertor, object runtime.Object, versions ...string) (runtime.Object, error) {
+func tryConvert(convertor runtime.ObjectConvertor, object runtime.Object, versions ...unversioned.GroupVersion) (runtime.Object, error) {
 	var last error
 	for _, version := range versions {
-		if len(version) == 0 {
+		if version.IsEmpty() {
 			return object, nil
 		}
 		obj, err := convertor.ConvertToVersion(object, version)

pkg/kubectl/resource_printer.go

@@ -182,7 +182,7 @@ func (p *VersionedPrinter) PrintObj(obj runtime.Object, w io.Writer) error {
 		if version.IsEmpty() {
 			continue
 		}
-		converted, err := p.convertor.ConvertToVersion(obj, version.String())
+		converted, err := p.convertor.ConvertToVersion(obj, version)
 		if runtime.IsNotRegisteredError(err) {
 			continue
 		}

pkg/kubectl/resource_printer_test.go

@@ -105,7 +105,7 @@ func TestPrinter(t *testing.T) {
 		},
 	}
 	emptyListTest := &api.PodList{}
-	testapi, err := api.Scheme.ConvertToVersion(podTest, testapi.Default.GroupVersion().String())
+	testapi, err := api.Scheme.ConvertToVersion(podTest, *testapi.Default.GroupVersion())
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
 	}

pkg/registry/thirdpartyresourcedata/codec.go

@@ -40,7 +40,7 @@ type thirdPartyObjectConverter struct {
 	converter runtime.ObjectConvertor
 }
 
-func (t *thirdPartyObjectConverter) ConvertToVersion(in runtime.Object, outVersion string) (out runtime.Object, err error) {
+func (t *thirdPartyObjectConverter) ConvertToVersion(in runtime.Object, outVersion unversioned.GroupVersion) (out runtime.Object, err error) {
 	switch in.(type) {
 	// This seems weird, but in this case the ThirdPartyResourceData is really just a wrapper on the raw 3rd party data.
 	// The actual thing printed/sent to server is the actual raw third party resource data, which only has one version.

pkg/runtime/codec.go

@@ -162,7 +162,7 @@ func (c *parameterCodec) EncodeParameters(obj Object, to unversioned.GroupVersio
 		return nil, err
 	}
 	if to != gvk.GroupVersion() {
-		out, err := c.convertor.ConvertToVersion(obj, to.String())
+		out, err := c.convertor.ConvertToVersion(obj, to)
 		if err != nil {
 			return nil, err
 		}

pkg/runtime/helper.go

@@ -43,10 +43,31 @@ func (t objectTyperToTyper) ObjectKind(obj Object) (*unversioned.GroupVersionKin
 	return &gvk, unversionedType, nil
 }
 
+// ObjectTyperToTyper casts the old typer interface to the new typer interface
 func ObjectTyperToTyper(typer ObjectTyper) Typer {
 	return objectTyperToTyper{typer: typer}
 }
 
+// unsafeObjectConvertor implements ObjectConvertor using the unsafe conversion path.
+type unsafeObjectConvertor struct {
+	*Scheme
+}
+
+var _ ObjectConvertor = unsafeObjectConvertor{}
+
+// ConvertToVersion converts in to the provided outVersion without copying the input first, which
+// is only safe if the output object is not mutated or reused.
+func (c unsafeObjectConvertor) ConvertToVersion(in Object, outVersion unversioned.GroupVersion) (Object, error) {
+	return c.Scheme.UnsafeConvertToVersion(in, outVersion)
+}
+
+// UnsafeObjectConvertor performs object conversion without copying the object structure,
+// for use when the converted object will not be reused or mutated. Primarily for use within
+// versioned codecs, which use the external object for serialization but do not return it.
+func UnsafeObjectConvertor(scheme *Scheme) ObjectConvertor {
+	return unsafeObjectConvertor{scheme}
+}
+
 // fieldPtr puts the address of fieldName, which must be a member of v,
 // into dest, which must be an address of a variable to which this field's
 // address can be assigned.

pkg/runtime/interfaces.go

@@ -161,7 +161,7 @@ type StorageSerializer interface {
 // Non-codec interfaces
 
 type ObjectVersioner interface {
-	ConvertToVersion(in Object, outVersion string) (out Object, err error)
+	ConvertToVersion(in Object, outVersion unversioned.GroupVersion) (out Object, err error)
 }
 
 // ObjectConvertor converts an object to a different version.
@@ -171,7 +171,7 @@ type ObjectConvertor interface {
 	Convert(in, out interface{}) error
 	// ConvertToVersion takes the provided object and converts it the provided version. This
 	// method does not guarantee that the in object is not mutated.
-	ConvertToVersion(in Object, outVersion string) (out Object, err error)
+	ConvertToVersion(in Object, outVersion unversioned.GroupVersion) (out Object, err error)
 	ConvertFieldLabel(version, kind, label, value string) (string, string, error)
 }
 

pkg/runtime/register.go

@@ -21,12 +21,12 @@ import (
 )
 
 // SetGroupVersionKind satisfies the ObjectKind interface for all objects that embed TypeMeta
-func (obj *TypeMeta) SetGroupVersionKind(gvk *unversioned.GroupVersionKind) {
+func (obj *TypeMeta) SetGroupVersionKind(gvk unversioned.GroupVersionKind) {
 	obj.APIVersion, obj.Kind = gvk.ToAPIVersionAndKind()
 }
 
 // GroupVersionKind satisfies the ObjectKind interface for all objects that embed TypeMeta
-func (obj *TypeMeta) GroupVersionKind() *unversioned.GroupVersionKind {
+func (obj *TypeMeta) GroupVersionKind() unversioned.GroupVersionKind {
 	return unversioned.FromAPIVersionAndKind(obj.APIVersion, obj.Kind)
 }
 

pkg/runtime/scheme.go

@@ -124,11 +124,8 @@ func (s *Scheme) nameFunc(t reflect.Type) string {
 
 // fromScope gets the input version, desired output version, and desired Scheme
 // from a conversion.Scope.
-func (s *Scheme) fromScope(scope conversion.Scope) (inVersion, outVersion string, scheme *Scheme) {
-	scheme = s
-	inVersion = scope.Meta().SrcVersion
-	outVersion = scope.Meta().DestVersion
-	return inVersion, outVersion, scheme
+func (s *Scheme) fromScope(scope conversion.Scope) *Scheme {
+	return s
 }
 
 // Converter allows access to the converter for the scheme
@@ -476,16 +473,12 @@ func (s *Scheme) ConvertFieldLabel(version, kind, label, value string) (string,
 // contain the inKind (or a mapping by name defined with AddKnownTypeWithName). Will also
 // return an error if the conversion does not result in a valid Object being
 // returned. The serializer handles loading/serializing nested objects.
-func (s *Scheme) ConvertToVersion(in Object, outVersion string) (Object, error) {
-	gv, err := unversioned.ParseGroupVersion(outVersion)
-	if err != nil {
-		return nil, err
-	}
+func (s *Scheme) ConvertToVersion(in Object, outVersion unversioned.GroupVersion) (Object, error) {
 	switch in.(type) {
 	case *Unknown, *Unstructured, *UnstructuredList:
 		old := in.GetObjectKind().GroupVersionKind()
 		defer in.GetObjectKind().SetGroupVersionKind(old)
-		setTargetVersion(in, s, gv)
+		setTargetVersion(in, s, outVersion)
 		return in, nil
 	}
 	t := reflect.TypeOf(in)
@@ -509,7 +502,7 @@ func (s *Scheme) ConvertToVersion(in Object, outVersion string) (Object, error)
 		kind = kinds[0]
 	}
 
-	outKind := gv.WithKind(kind.Kind)
+	outKind := outVersion.WithKind(kind.Kind)
 
 	inKind, err := s.ObjectKind(in)
 	if err != nil {
@@ -521,29 +514,106 @@ func (s *Scheme) ConvertToVersion(in Object, outVersion string) (Object, error)
 		return nil, err
 	}
 
-	flags, meta := s.generateConvertMeta(inKind.GroupVersion(), gv, in)
+	flags, meta := s.generateConvertMeta(inKind.GroupVersion(), outVersion, in)
 	if err := s.converter.Convert(in, out, flags, meta); err != nil {
 		return nil, err
 	}
 
-	setTargetVersion(out, s, gv)
+	setTargetVersion(out, s, outVersion)
+	return out, nil
+}
+
+// UnsafeConvertToVersion will convert in to the provided outVersion if such a conversion is possible,
+// but does not guarantee the output object does not share fields with the input object. It attempts to be as
+// efficient as possible when doing conversion.
+func (s *Scheme) UnsafeConvertToVersion(in Object, outVersion unversioned.GroupVersion) (Object, error) {
+	switch t := in.(type) {
+	case *Unknown:
+		t.APIVersion = outVersion.String()
+		return t, nil
+	case *Unstructured:
+		t.SetAPIVersion(outVersion.String())
+		return t, nil
+	case *UnstructuredList:
+		t.SetAPIVersion(outVersion.String())
+		return t, nil
+	}
+
+	// determine the incoming kinds with as few allocations as possible.
+	t := reflect.TypeOf(in)
+	if t.Kind() != reflect.Ptr {
+		return nil, fmt.Errorf("only pointer types may be converted: %v", t)
+	}
+	t = t.Elem()
+	if t.Kind() != reflect.Struct {
+		return nil, fmt.Errorf("only pointers to struct types may be converted: %v", t)
+	}
+	kinds, ok := s.typeToGVK[t]
+	if !ok || len(kinds) == 0 {
+		return nil, fmt.Errorf("%v is not a registered type and cannot be converted into version %q", t, outVersion)
+	}
+
+	// if the Go type is also registered to the destination kind, no conversion is necessary
+	for i := range kinds {
+		if kinds[i].Version == outVersion.Version && kinds[i].Group == outVersion.Group {
+			setTargetKind(in, kinds[i])
+			return in, nil
+		}
+	}
+
+	// type is unversioned, no conversion necessary
+	// it should be possible to avoid this allocation
+	if unversionedKind, ok := s.unversionedTypes[t]; ok {
+		kind := unversionedKind
+		outKind := outVersion.WithKind(kind.Kind)
+		setTargetKind(in, outKind)
+		return in, nil
+	}
+
+	// allocate a new object as the target using the target kind
+	// TODO: this should look in the target group version and find the first kind that matches, rather than the
+	//   first kind registered in typeToGVK
+	kind := kinds[0]
+	kind.Version = outVersion.Version
+	kind.Group = outVersion.Group
+	out, err := s.New(kind)
+	if err != nil {
+		return nil, err
+	}
+
+	// TODO: try to avoid the allocations here - in fast paths we are not likely to need these flags or meta
+	flags, meta := s.converter.DefaultMeta(t)
+	if err := s.converter.Convert(in, out, flags, meta); err != nil {
+		return nil, err
+	}
+
+	setTargetKind(out, kind)
 	return out, nil
 }
 
 // generateConvertMeta constructs the meta value we pass to Convert.
 func (s *Scheme) generateConvertMeta(srcGroupVersion, destGroupVersion unversioned.GroupVersion, in interface{}) (conversion.FieldMatchingFlags, *conversion.Meta) {
-	flags, meta := s.converter.DefaultMeta(reflect.TypeOf(in))
-	meta.SrcVersion = srcGroupVersion.String()
-	meta.DestVersion = destGroupVersion.String()
-	return flags, meta
+	return s.converter.DefaultMeta(reflect.TypeOf(in))
 }
 
+// setTargetVersion is deprecated and should be replaced by use of setTargetKind
 func setTargetVersion(obj Object, raw *Scheme, gv unversioned.GroupVersion) {
 	if gv.Version == APIVersionInternal {
 		// internal is a special case
-		obj.GetObjectKind().SetGroupVersionKind(nil)
-	} else {
-		gvk, _ := raw.ObjectKind(obj)
-		obj.GetObjectKind().SetGroupVersionKind(&unversioned.GroupVersionKind{Group: gv.Group, Version: gv.Version, Kind: gvk.Kind})
+		obj.GetObjectKind().SetGroupVersionKind(unversioned.GroupVersionKind{})
+		return
+	}
+	gvk, _ := raw.ObjectKind(obj)
+	obj.GetObjectKind().SetGroupVersionKind(unversioned.GroupVersionKind{Group: gv.Group, Version: gv.Version, Kind: gvk.Kind})
+}
+
+// setTargetKind sets the kind on an object, taking into account whether the target kind is the internal version.
+func setTargetKind(obj Object, kind unversioned.GroupVersionKind) {
+	if kind.Version == APIVersionInternal {
+		// internal is a special case
+		// TODO: look at removing the need to special case this
+		obj.GetObjectKind().SetGroupVersionKind(unversioned.GroupVersionKind{})
+		return
 	}
+	obj.GetObjectKind().SetGroupVersionKind(kind)
 }

pkg/runtime/scheme_test.go

@@ -65,24 +65,12 @@ func TestScheme(t *testing.T) {
 	// Register functions to verify that scope.Meta() gets set correctly.
 	err := scheme.AddConversionFuncs(
 		func(in *InternalSimple, out *ExternalSimple, scope conversion.Scope) error {
-			if e, a := internalGV.String(), scope.Meta().SrcVersion; e != a {
-				t.Errorf("Expected '%v', got '%v'", e, a)
-			}
-			if e, a := externalGV.String(), scope.Meta().DestVersion; e != a {
-				t.Errorf("Expected '%v', got '%v'", e, a)
-			}
 			scope.Convert(&in.TypeMeta, &out.TypeMeta, 0)
 			scope.Convert(&in.TestString, &out.TestString, 0)
 			internalToExternalCalls++
 			return nil
 		},
 		func(in *ExternalSimple, out *InternalSimple, scope conversion.Scope) error {
-			if e, a := externalGV.String(), scope.Meta().SrcVersion; e != a {
-				t.Errorf("Expected '%v', got '%v'", e, a)
-			}
-			if e, a := internalGV.String(), scope.Meta().DestVersion; e != a {
-				t.Errorf("Expected '%v', got '%v'", e, a)
-			}
 			scope.Convert(&in.TypeMeta, &out.TypeMeta, 0)
 			scope.Convert(&in.TestString, &out.TestString, 0)
 			externalToInternalCalls++
@@ -472,10 +460,10 @@ type ExternalInternalSame struct {
 }
 
 func (obj *MyWeirdCustomEmbeddedVersionKindField) GetObjectKind() unversioned.ObjectKind { return obj }
-func (obj *MyWeirdCustomEmbeddedVersionKindField) SetGroupVersionKind(gvk *unversioned.GroupVersionKind) {
+func (obj *MyWeirdCustomEmbeddedVersionKindField) SetGroupVersionKind(gvk unversioned.GroupVersionKind) {
 	obj.APIVersion, obj.ObjectKind = gvk.ToAPIVersionAndKind()
 }
-func (obj *MyWeirdCustomEmbeddedVersionKindField) GroupVersionKind() *unversioned.GroupVersionKind {
+func (obj *MyWeirdCustomEmbeddedVersionKindField) GroupVersionKind() unversioned.GroupVersionKind {
 	return unversioned.FromAPIVersionAndKind(obj.APIVersion, obj.ObjectKind)
 }
 
@@ -542,7 +530,7 @@ func TestKnownTypes(t *testing.T) {
 func TestConvertToVersion(t *testing.T) {
 	s := GetTestScheme()
 	tt := &TestType1{A: "I'm not a pointer object"}
-	other, err := s.ConvertToVersion(tt, "v1")
+	other, err := s.ConvertToVersion(tt, unversioned.GroupVersion{Version: "v1"})
 	if err != nil {
 		t.Fatalf("Failure: %v", err)
 	}
@@ -570,24 +558,12 @@ func TestMetaValues(t *testing.T) {
 	err := s.AddConversionFuncs(
 		func(in *InternalSimple, out *ExternalSimple, scope conversion.Scope) error {
 			t.Logf("internal -> external")
-			if e, a := internalGV.String(), scope.Meta().SrcVersion; e != a {
-				t.Fatalf("Expected '%v', got '%v'", e, a)
-			}
-			if e, a := externalGV.String(), scope.Meta().DestVersion; e != a {
-				t.Fatalf("Expected '%v', got '%v'", e, a)
-			}
 			scope.Convert(&in.TestString, &out.TestString, 0)
 			internalToExternalCalls++
 			return nil
 		},
 		func(in *ExternalSimple, out *InternalSimple, scope conversion.Scope) error {
 			t.Logf("external -> internal")
-			if e, a := externalGV.String(), scope.Meta().SrcVersion; e != a {
-				t.Errorf("Expected '%v', got '%v'", e, a)
-			}
-			if e, a := internalGV.String(), scope.Meta().DestVersion; e != a {
-				t.Fatalf("Expected '%v', got '%v'", e, a)
-			}
 			scope.Convert(&in.TestString, &out.TestString, 0)
 			externalToInternalCalls++
 			return nil
@@ -602,12 +578,12 @@ func TestMetaValues(t *testing.T) {
 
 	s.Log(t)
 
-	out, err := s.ConvertToVersion(simple, externalGV.String())
+	out, err := s.ConvertToVersion(simple, externalGV)
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
 	}
 
-	internal, err := s.ConvertToVersion(out, internalGV.String())
+	internal, err := s.ConvertToVersion(out, internalGV)
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
 	}
@@ -643,12 +619,6 @@ func TestMetaValuesUnregisteredConvert(t *testing.T) {
 	// Register functions to verify that scope.Meta() gets set correctly.
 	err := s.AddConversionFuncs(
 		func(in *InternalSimple, out *ExternalSimple, scope conversion.Scope) error {
-			if e, a := "unknown/unknown", scope.Meta().SrcVersion; e != a {
-				t.Fatalf("Expected '%v', got '%v'", e, a)
-			}
-			if e, a := "unknown/unknown", scope.Meta().DestVersion; e != a {
-				t.Fatalf("Expected '%v', got '%v'", e, a)
-			}
 			scope.Convert(&in.TestString, &out.TestString, 0)
 			internalToExternalCalls++
 			return nil

pkg/runtime/serializer/codec_test.go

@@ -129,10 +129,10 @@ var TestObjectFuzzer = fuzz.New().NilChance(.5).NumElements(1, 100).Funcs(
 )
 
 func (obj *MyWeirdCustomEmbeddedVersionKindField) GetObjectKind() unversioned.ObjectKind { return obj }
-func (obj *MyWeirdCustomEmbeddedVersionKindField) SetGroupVersionKind(gvk *unversioned.GroupVersionKind) {
+func (obj *MyWeirdCustomEmbeddedVersionKindField) SetGroupVersionKind(gvk unversioned.GroupVersionKind) {
 	obj.APIVersion, obj.ObjectKind = gvk.ToAPIVersionAndKind()
 }
-func (obj *MyWeirdCustomEmbeddedVersionKindField) GroupVersionKind() *unversioned.GroupVersionKind {
+func (obj *MyWeirdCustomEmbeddedVersionKindField) GroupVersionKind() unversioned.GroupVersionKind {
 	return unversioned.FromAPIVersionAndKind(obj.APIVersion, obj.ObjectKind)
 }
 

pkg/runtime/serializer/json/json.go

@@ -111,7 +111,7 @@ func (s *Serializer) Decode(originalData []byte, gvk *unversioned.GroupVersionKi
 	if unk, ok := into.(*runtime.Unknown); ok && unk != nil {
 		unk.Raw = originalData
 		unk.ContentType = runtime.ContentTypeJSON
-		unk.GetObjectKind().SetGroupVersionKind(actual)
+		unk.GetObjectKind().SetGroupVersionKind(*actual)
 		return unk, actual, nil
 	}
 

pkg/runtime/serializer/json/json_test.go

@@ -31,12 +31,12 @@ import (
 type testDecodable struct {
 	Other string
 	Value int `json:"value"`
-	gvk   *unversioned.GroupVersionKind
+	gvk   unversioned.GroupVersionKind
 }
 
-func (d *testDecodable) GetObjectKind() unversioned.ObjectKind                 { return d }
-func (d *testDecodable) SetGroupVersionKind(gvk *unversioned.GroupVersionKind) { d.gvk = gvk }
-func (d *testDecodable) GroupVersionKind() *unversioned.GroupVersionKind       { return d.gvk }
+func (d *testDecodable) GetObjectKind() unversioned.ObjectKind                { return d }
+func (d *testDecodable) SetGroupVersionKind(gvk unversioned.GroupVersionKind) { d.gvk = gvk }
+func (d *testDecodable) GroupVersionKind() unversioned.GroupVersionKind       { return d.gvk }
 
 func TestDecode(t *testing.T) {
 	testCases := []struct {
@@ -76,34 +76,28 @@ func TestDecode(t *testing.T) {
 			errFn:       func(err error) bool { return err.Error() == "fake error" },
 		},
 		{
-			data:       []byte("{}"),
-			defaultGVK: &unversioned.GroupVersionKind{Kind: "Test", Group: "other", Version: "blah"},
-			creater:    &mockCreater{obj: &testDecodable{}},
-			expectedObject: &testDecodable{
-				gvk: nil, // json serializer does NOT set GVK
-			},
-			expectedGVK: &unversioned.GroupVersionKind{Kind: "Test", Group: "other", Version: "blah"},
+			data:           []byte("{}"),
+			defaultGVK:     &unversioned.GroupVersionKind{Kind: "Test", Group: "other", Version: "blah"},
+			creater:        &mockCreater{obj: &testDecodable{}},
+			expectedObject: &testDecodable{},
+			expectedGVK:    &unversioned.GroupVersionKind{Kind: "Test", Group: "other", Version: "blah"},
 		},
 
 		// version without group is not defaulted
 		{
-			data:       []byte(`{"apiVersion":"blah"}`),
-			defaultGVK: &unversioned.GroupVersionKind{Kind: "Test", Group: "other", Version: "blah"},
-			creater:    &mockCreater{obj: &testDecodable{}},
-			expectedObject: &testDecodable{
-				gvk: nil, // json serializer does NOT set GVK
-			},
-			expectedGVK: &unversioned.GroupVersionKind{Kind: "Test", Group: "", Version: "blah"},
+			data:           []byte(`{"apiVersion":"blah"}`),
+			defaultGVK:     &unversioned.GroupVersionKind{Kind: "Test", Group: "other", Version: "blah"},
+			creater:        &mockCreater{obj: &testDecodable{}},
+			expectedObject: &testDecodable{},
+			expectedGVK:    &unversioned.GroupVersionKind{Kind: "Test", Group: "", Version: "blah"},
 		},
 		// group without version is defaulted
 		{
-			data:       []byte(`{"apiVersion":"other/"}`),
-			defaultGVK: &unversioned.GroupVersionKind{Kind: "Test", Group: "other", Version: "blah"},
-			creater:    &mockCreater{obj: &testDecodable{}},
-			expectedObject: &testDecodable{
-				gvk: nil, // json serializer does NOT set GVK
-			},
-			expectedGVK: &unversioned.GroupVersionKind{Kind: "Test", Group: "other", Version: "blah"},
+			data:           []byte(`{"apiVersion":"other/"}`),
+			defaultGVK:     &unversioned.GroupVersionKind{Kind: "Test", Group: "other", Version: "blah"},
+			creater:        &mockCreater{obj: &testDecodable{}},
+			expectedObject: &testDecodable{},
+			expectedGVK:    &unversioned.GroupVersionKind{Kind: "Test", Group: "other", Version: "blah"},
 		},
 
 		// accept runtime.Unknown as into and bypass creator

pkg/runtime/serializer/protobuf/protobuf.go

@@ -120,14 +120,14 @@ func (s *Serializer) Decode(originalData []byte, gvk *unversioned.GroupVersionKi
 	}
 
 	actual := unk.GroupVersionKind()
-	copyKindDefaults(actual, gvk)
+	copyKindDefaults(&actual, gvk)
 
 	if intoUnknown, ok := into.(*runtime.Unknown); ok && intoUnknown != nil {
 		*intoUnknown = unk
 		if len(intoUnknown.ContentType) == 0 {
 			intoUnknown.ContentType = s.contentType
 		}
-		return intoUnknown, actual, nil
+		return intoUnknown, &actual, nil
 	}
 
 	if into != nil {
@@ -136,16 +136,16 @@ func (s *Serializer) Decode(originalData []byte, gvk *unversioned.GroupVersionKi
 		case runtime.IsNotRegisteredError(err):
 			pb, ok := into.(proto.Message)
 			if !ok {
-				return nil, actual, errNotMarshalable{reflect.TypeOf(into)}
+				return nil, &actual, errNotMarshalable{reflect.TypeOf(into)}
 			}
 			if err := proto.Unmarshal(unk.Raw, pb); err != nil {
-				return nil, actual, err
+				return nil, &actual, err
 			}
-			return into, actual, nil
+			return into, &actual, nil
 		case err != nil:
-			return nil, actual, err
+			return nil, &actual, err
 		default:
-			copyKindDefaults(actual, typed)
+			copyKindDefaults(&actual, typed)
 			// if the result of defaulting did not set a version or group, ensure that at least group is set
 			// (copyKindDefaults will not assign Group if version is already set). This guarantees that the group
 			// of into is set if there is no better information from the caller or object.
@@ -156,25 +156,24 @@ func (s *Serializer) Decode(originalData []byte, gvk *unversioned.GroupVersionKi
 	}
 
 	if len(actual.Kind) == 0 {
-		return nil, actual, runtime.NewMissingKindErr(fmt.Sprintf("%#v", unk.TypeMeta))
+		return nil, &actual, runtime.NewMissingKindErr(fmt.Sprintf("%#v", unk.TypeMeta))
 	}
 	if len(actual.Version) == 0 {
-		return nil, actual, runtime.NewMissingVersionErr(fmt.Sprintf("%#v", unk.TypeMeta))
+		return nil, &actual, runtime.NewMissingVersionErr(fmt.Sprintf("%#v", unk.TypeMeta))
 	}
 
-	return unmarshalToObject(s.typer, s.creater, actual, into, unk.Raw)
+	return unmarshalToObject(s.typer, s.creater, &actual, into, unk.Raw)
 }
 
 // EncodeToStream serializes the provided object to the given writer. Overrides is ignored.
 func (s *Serializer) EncodeToStream(obj runtime.Object, w io.Writer, overrides ...unversioned.GroupVersion) error {
 	var unk runtime.Unknown
-	if kind := obj.GetObjectKind().GroupVersionKind(); kind != nil {
-		unk = runtime.Unknown{
-			TypeMeta: runtime.TypeMeta{
-				Kind:       kind.Kind,
-				APIVersion: kind.GroupVersion().String(),
-			},
-		}
+	kind := obj.GetObjectKind().GroupVersionKind()
+	unk = runtime.Unknown{
+		TypeMeta: runtime.TypeMeta{
+			Kind:       kind.Kind,
+			APIVersion: kind.GroupVersion().String(),
+		},
 	}
 
 	prefixSize := uint64(len(s.prefix))
@@ -334,7 +333,7 @@ func (s *RawSerializer) Decode(originalData []byte, gvk *unversioned.GroupVersio
 		intoUnknown.Raw = data
 		intoUnknown.ContentEncoding = ""
 		intoUnknown.ContentType = s.contentType
-		intoUnknown.SetGroupVersionKind(actual)
+		intoUnknown.SetGroupVersionKind(*actual)
 		return intoUnknown, actual, nil
 	}
 

pkg/runtime/serializer/protobuf/protobuf_test.go

@@ -34,12 +34,12 @@ import (
 )
 
 type testObject struct {
-	gvk *unversioned.GroupVersionKind
+	gvk unversioned.GroupVersionKind
 }
 
-func (d *testObject) GetObjectKind() unversioned.ObjectKind                 { return d }
-func (d *testObject) SetGroupVersionKind(gvk *unversioned.GroupVersionKind) { d.gvk = gvk }
-func (d *testObject) GroupVersionKind() *unversioned.GroupVersionKind       { return d.gvk }
+func (d *testObject) GetObjectKind() unversioned.ObjectKind                { return d }
+func (d *testObject) SetGroupVersionKind(gvk unversioned.GroupVersionKind) { d.gvk = gvk }
+func (d *testObject) GroupVersionKind() unversioned.GroupVersionKind       { return d.gvk }
 
 type testMarshalable struct {
 	testObject
@@ -106,7 +106,7 @@ func TestEncode(t *testing.T) {
 		0x22, 0x00, // content-encoding
 	}
 	obj2 := &testMarshalable{
-		testObject: testObject{gvk: &unversioned.GroupVersionKind{Kind: "test", Group: "other", Version: "version"}},
+		testObject: testObject{gvk: unversioned.GroupVersionKind{Kind: "test", Group: "other", Version: "version"}},
 		data:       []byte{0x01, 0x02, 0x03},
 	}
 	wire2 := []byte{

pkg/runtime/serializer/versioning/versioning.go

@@ -71,7 +71,7 @@ func NewCodecForScheme(
 	encodeVersion []unversioned.GroupVersion,
 	decodeVersion []unversioned.GroupVersion,
 ) runtime.Codec {
-	return NewCodec(encoder, decoder, scheme, scheme, scheme, runtime.ObjectTyperToTyper(scheme), encodeVersion, decodeVersion)
+	return NewCodec(encoder, decoder, runtime.UnsafeObjectConvertor(scheme), scheme, scheme, runtime.ObjectTyperToTyper(scheme), encodeVersion, decodeVersion)
 }
 
 // NewCodec takes objects in their internal versions and converts them to external versions before
@@ -204,7 +204,7 @@ func (c *codec) Decode(data []byte, defaultGVK *unversioned.GroupVersionKind, in
 	}
 
 	// Convert if needed.
-	out, err := c.convertor.ConvertToVersion(obj, targetGV.String())
+	out, err := c.convertor.ConvertToVersion(obj, targetGV)
 	if err != nil {
 		return nil, gvk, err
 	}
@@ -227,10 +227,12 @@ func (c *codec) EncodeToStream(obj runtime.Object, w io.Writer, overrides ...unv
 	}
 
 	if (c.encodeVersion == nil && len(overrides) == 0) || isUnversioned {
-		old := obj.GetObjectKind().GroupVersionKind()
-		obj.GetObjectKind().SetGroupVersionKind(gvk)
-		defer obj.GetObjectKind().SetGroupVersionKind(old)
-		return c.encoder.EncodeToStream(obj, w, overrides...)
+		objectKind := obj.GetObjectKind()
+		old := objectKind.GroupVersionKind()
+		objectKind.SetGroupVersionKind(*gvk)
+		err = c.encoder.EncodeToStream(obj, w, overrides...)
+		objectKind.SetGroupVersionKind(old)
+		return err
 	}
 
 	targetGV, ok := c.encodeVersion[gvk.Group]
@@ -261,22 +263,21 @@ func (c *codec) EncodeToStream(obj runtime.Object, w io.Writer, overrides ...unv
 	}
 
 	// Perform a conversion if necessary
-	if gvk.GroupVersion() != targetGV {
-		out, err := c.convertor.ConvertToVersion(obj, targetGV.String())
-		if err != nil {
-			if ok {
-				return err
-			}
-		} else {
-			obj = out
+	objectKind := obj.GetObjectKind()
+	old := objectKind.GroupVersionKind()
+	out, err := c.convertor.ConvertToVersion(obj, targetGV)
+	if err != nil {
+		if ok {
+			return err
 		}
 	} else {
-		old := obj.GetObjectKind().GroupVersionKind()
-		defer obj.GetObjectKind().SetGroupVersionKind(old)
-		obj.GetObjectKind().SetGroupVersionKind(&unversioned.GroupVersionKind{Group: targetGV.Group, Version: targetGV.Version, Kind: gvk.Kind})
+		obj = out
 	}
-
-	return c.encoder.EncodeToStream(obj, w, overrides...)
+	// Conversion is responsible for setting the proper group, version, and kind onto the outgoing object
+	err = c.encoder.EncodeToStream(obj, w, overrides...)
+	// restore the old GVK, in case conversion returned the same object
+	objectKind.SetGroupVersionKind(old)
+	return err
 }
 
 // promoteOrPrependGroupVersion finds the group version in the provided group versions that has the same group as target.

pkg/runtime/serializer/versioning/versioning_test.go

@@ -30,12 +30,12 @@ import (
 type testDecodable struct {
 	Other string
 	Value int `json:"value"`
-	gvk   *unversioned.GroupVersionKind
+	gvk   unversioned.GroupVersionKind
 }
 
-func (d *testDecodable) GetObjectKind() unversioned.ObjectKind                 { return d }
-func (d *testDecodable) SetGroupVersionKind(gvk *unversioned.GroupVersionKind) { d.gvk = gvk }
-func (d *testDecodable) GroupVersionKind() *unversioned.GroupVersionKind       { return d.gvk }
+func (d *testDecodable) GetObjectKind() unversioned.ObjectKind                { return d }
+func (d *testDecodable) SetGroupVersionKind(gvk unversioned.GroupVersionKind) { d.gvk = gvk }
+func (d *testDecodable) GroupVersionKind() unversioned.GroupVersionKind       { return d.gvk }
 
 func TestDecode(t *testing.T) {
 	gvk1 := &unversioned.GroupVersionKind{Kind: "Test", Group: "other", Version: "blah"}
@@ -65,12 +65,12 @@ func TestDecode(t *testing.T) {
 	}{
 		{
 			serializer:  &mockSerializer{actual: gvk1},
-			convertor:   &checkConvertor{groupVersion: "other/__internal"},
+			convertor:   &checkConvertor{groupVersion: unversioned.GroupVersion{Group: "other", Version: "__internal"}},
 			expectedGVK: gvk1,
 		},
 		{
 			serializer:  &mockSerializer{actual: gvk1, obj: decodable1},
-			convertor:   &checkConvertor{in: decodable1, obj: decodable2, groupVersion: "other/__internal"},
+			convertor:   &checkConvertor{in: decodable1, obj: decodable2, groupVersion: unversioned.GroupVersion{Group: "other", Version: "__internal"}},
 			expectedGVK: gvk1,
 			sameObject:  decodable2,
 		},
@@ -78,7 +78,7 @@ func TestDecode(t *testing.T) {
 		{
 			serializer:  &mockSerializer{actual: gvk1, obj: decodable1},
 			defaultGVK:  &unversioned.GroupVersionKind{Group: "force"},
-			convertor:   &checkConvertor{in: decodable1, obj: decodable2, groupVersion: "force/__internal"},
+			convertor:   &checkConvertor{in: decodable1, obj: decodable2, groupVersion: unversioned.GroupVersion{Group: "force", Version: "__internal"}},
 			expectedGVK: gvk1,
 			sameObject:  decodable2,
 		},
@@ -118,7 +118,7 @@ func TestDecode(t *testing.T) {
 
 			serializer:     &mockSerializer{actual: gvk1, obj: decodable1},
 			copier:         &checkCopy{in: decodable1, obj: decodable1},
-			convertor:      &checkConvertor{in: decodable1, obj: decodable2, groupVersion: "other/__internal"},
+			convertor:      &checkConvertor{in: decodable1, obj: decodable2, groupVersion: unversioned.GroupVersion{Group: "other", Version: "__internal"}},
 			expectedGVK:    gvk1,
 			expectedObject: &runtime.VersionedObjects{Objects: []runtime.Object{decodable1, decodable2}},
 		},
@@ -127,7 +127,7 @@ func TestDecode(t *testing.T) {
 
 			serializer:     &mockSerializer{actual: gvk1, obj: decodable1},
 			copier:         &checkCopy{in: decodable1, obj: nil, err: fmt.Errorf("error on copy")},
-			convertor:      &checkConvertor{in: decodable1, obj: decodable2, groupVersion: "other/__internal"},
+			convertor:      &checkConvertor{in: decodable1, obj: decodable2, groupVersion: unversioned.GroupVersion{Group: "other", Version: "__internal"}},
 			expectedGVK:    gvk1,
 			expectedObject: &runtime.VersionedObjects{Objects: []runtime.Object{decodable1, decodable2}},
 		},
@@ -228,7 +228,7 @@ func (c *checkCopy) Copy(obj runtime.Object) (runtime.Object, error) {
 type checkConvertor struct {
 	err           error
 	in, obj       runtime.Object
-	groupVersion  string
+	groupVersion  unversioned.GroupVersion
 	directConvert bool
 }
 
@@ -244,7 +244,7 @@ func (c *checkConvertor) Convert(in, out interface{}) error {
 	}
 	return c.err
 }
-func (c *checkConvertor) ConvertToVersion(in runtime.Object, outVersion string) (out runtime.Object, err error) {
+func (c *checkConvertor) ConvertToVersion(in runtime.Object, outVersion unversioned.GroupVersion) (out runtime.Object, err error) {
 	if c.directConvert {
 		return nil, fmt.Errorf("unexpected call to ConvertToVersion")
 	}

pkg/runtime/types.go

@@ -301,18 +301,18 @@ func (u *Unstructured) SetAnnotations(annotations map[string]string) {
 	u.setNestedMap(annotations, "metadata", "annotations")
 }
 
-func (u *Unstructured) SetGroupVersionKind(gvk *unversioned.GroupVersionKind) {
+func (u *Unstructured) SetGroupVersionKind(gvk unversioned.GroupVersionKind) {
 	u.SetAPIVersion(gvk.GroupVersion().String())
 	u.SetKind(gvk.Kind)
 }
 
-func (u *Unstructured) GroupVersionKind() *unversioned.GroupVersionKind {
+func (u *Unstructured) GroupVersionKind() unversioned.GroupVersionKind {
 	gv, err := unversioned.ParseGroupVersion(u.GetAPIVersion())
 	if err != nil {
-		return nil
+		return unversioned.GroupVersionKind{}
 	}
 	gvk := gv.WithKind(u.GetKind())
-	return &gvk
+	return gvk
 }
 
 // UnstructuredList allows lists that do not have Golang structs
@@ -364,18 +364,18 @@ func (u *UnstructuredList) SetSelfLink(selfLink string) {
 	u.setNestedField(selfLink, "metadata", "selfLink")
 }
 
-func (u *UnstructuredList) SetGroupVersionKind(gvk *unversioned.GroupVersionKind) {
+func (u *UnstructuredList) SetGroupVersionKind(gvk unversioned.GroupVersionKind) {
 	u.SetAPIVersion(gvk.GroupVersion().String())
 	u.SetKind(gvk.Kind)
 }
 
-func (u *UnstructuredList) GroupVersionKind() *unversioned.GroupVersionKind {
+func (u *UnstructuredList) GroupVersionKind() unversioned.GroupVersionKind {
 	gv, err := unversioned.ParseGroupVersion(u.GetAPIVersion())
 	if err != nil {
-		return nil
+		return unversioned.GroupVersionKind{}
 	}
 	gvk := gv.WithKind(u.GetKind())
-	return &gvk
+	return gvk
 }
 
 // VersionedObjects is used by Decoders to give callers a way to access all versions

pkg/runtime/unstructured.go

@@ -45,10 +45,10 @@ func (s unstructuredJSONScheme) Decode(data []byte, _ *unversioned.GroupVersionK
 
 	gvk := obj.GetObjectKind().GroupVersionKind()
 	if len(gvk.Kind) == 0 {
-		return nil, gvk, NewMissingKindErr(string(data))
+		return nil, &gvk, NewMissingKindErr(string(data))
 	}
 
-	return obj, gvk, nil
+	return obj, &gvk, nil
 }
 
 func (unstructuredJSONScheme) EncodeToStream(obj Object, w io.Writer, overrides ...unversioned.GroupVersion) error {