utils: Add GenerateKubeVirtGroupVersionKind

GenerateKubeVirtGroupVersionKind ensures a provided object registered
with KubeVirts generated schema has GVK set correctly. This is required
as client-go continues to return objects without TypeMeta set as set out
in the following closed but often cited issue:

Object's TypeMeta is empty
kubernetes/client-go#413

Signed-off-by: Lee Yarwood <lyarwood@redhat.com>

pkg/instancetype/BUILD.bazel

@@ -9,6 +9,7 @@ go_library(
     importpath = "kubevirt.io/kubevirt/pkg/instancetype",
     visibility = ["//visibility:public"],
     deps = [
+        "//pkg/util:go_default_library",
         "//pkg/util/types:go_default_library",
         "//staging/src/kubevirt.io/api/core/v1:go_default_library",
         "//staging/src/kubevirt.io/api/instancetype:go_default_library",

pkg/instancetype/instancetype.go

@@ -23,6 +23,7 @@ import (
 	"kubevirt.io/client-go/kubecli"
 	"kubevirt.io/client-go/log"
 
+	utils "kubevirt.io/kubevirt/pkg/util"
 	utiltypes "kubevirt.io/kubevirt/pkg/util/types"
 )
 
@@ -60,17 +61,15 @@ func GetRevisionName(vmName, resourceName string, resourceUID types.UID, resourc
 }
 
 func CreateControllerRevision(vm *virtv1.VirtualMachine, object runtime.Object) (*appsv1.ControllerRevision, error) {
-	objCopy := object.DeepCopyObject()
-
-	// TypeMeta may be missing, so set it here.
-	gvks, _, err := generatedscheme.Scheme.ObjectKinds(objCopy)
+	obj, err := utils.GenerateKubeVirtGroupVersionKind(object)
 	if err != nil {
-		// This is a programmer's error and should not happen.
-		return nil, fmt.Errorf("could not get GroupVersionKind for object: %w", err)
+		return nil, err
+	}
+	metaObj, ok := obj.(metav1.Object)
+	if !ok {
+		return nil, fmt.Errorf("Unexpected object format returned from GenerateKubeVirtGroupVersionKind")
 	}
-	objCopy.GetObjectKind().SetGroupVersionKind(gvks[0])
 
-	metaObj := objCopy.(metav1.Object)
 	revisionName := GetRevisionName(vm.Name, metaObj.GetName(), metaObj.GetUID(), metaObj.GetGeneration())
 
 	// Removing unnecessary metadata
@@ -87,7 +86,7 @@ func CreateControllerRevision(vm *virtv1.VirtualMachine, object runtime.Object)
 			OwnerReferences: []metav1.OwnerReference{*metav1.NewControllerRef(vm, virtv1.VirtualMachineGroupVersionKind)},
 		},
 		Data: runtime.RawExtension{
-			Object: objCopy,
+			Object: obj,
 		},
 	}, nil
 }

pkg/storage/snapshot/BUILD.bazel

@@ -15,12 +15,12 @@ go_library(
     deps = [
         "//pkg/controller:go_default_library",
         "//pkg/storage/types:go_default_library",
+        "//pkg/util:go_default_library",
         "//pkg/util/status:go_default_library",
         "//pkg/virt-controller/watch/util:go_default_library",
         "//pkg/virt-launcher/virtwrap/api:go_default_library",
         "//staging/src/kubevirt.io/api/core/v1:go_default_library",
         "//staging/src/kubevirt.io/api/snapshot/v1alpha1:go_default_library",
-        "//staging/src/kubevirt.io/client-go/generated/kubevirt/clientset/versioned/scheme:go_default_library",
         "//staging/src/kubevirt.io/client-go/kubecli:go_default_library",
         "//staging/src/kubevirt.io/client-go/log:go_default_library",
         "//vendor/github.com/evanphx/json-patch:go_default_library",

pkg/storage/snapshot/source.go

@@ -35,11 +35,11 @@ import (
 
 	kubevirtv1 "kubevirt.io/api/core/v1"
 	snapshotv1 "kubevirt.io/api/snapshot/v1alpha1"
-	generatedscheme "kubevirt.io/client-go/generated/kubevirt/clientset/versioned/scheme"
 	"kubevirt.io/client-go/log"
 
 	"kubevirt.io/kubevirt/pkg/controller"
 	storagetypes "kubevirt.io/kubevirt/pkg/storage/types"
+	utils "kubevirt.io/kubevirt/pkg/util"
 	watchutil "kubevirt.io/kubevirt/pkg/virt-controller/watch/util"
 	launcherapi "kubevirt.io/kubevirt/pkg/virt-launcher/virtwrap/api"
 )
@@ -212,14 +212,16 @@ func (s *vmSnapshotSource) captureInstancetypeControllerRevision(namespace, revi
 	// We strip out the source VM name from the CR name and replace it with the snapshot name
 	snapshotCR.Name = s.snapshot.Name + strings.ReplaceAll(existingCR.Name, s.snapshot.Spec.Source.Name, "")
 
-	// TODO - share with pkg/instancetype somewhere
-	snapshotCopy := s.snapshot.DeepCopy()
-	gvks, _, err := generatedscheme.Scheme.ObjectKinds(snapshotCopy)
+	// Ensure GVK is set before we attempt to create the controller OwnerReference below
+	obj, err := utils.GenerateKubeVirtGroupVersionKind(s.snapshot)
 	if err != nil {
-		return "", fmt.Errorf("could not get GroupVersionKind for object: %w", err)
+		return "", err
+	}
+	snapshot, ok := obj.(*snapshotv1.VirtualMachineSnapshot)
+	if !ok {
+		return "", fmt.Errorf("Unexpected object format returned from GenerateKubeVirtGroupVersionKind")
 	}
-	snapshotCopy.GetObjectKind().SetGroupVersionKind(gvks[0])
-	snapshotCR.OwnerReferences = []metav1.OwnerReference{*metav1.NewControllerRef(snapshotCopy, snapshotCopy.GroupVersionKind())}
+	snapshotCR.OwnerReferences = []metav1.OwnerReference{*metav1.NewControllerRef(snapshot, snapshot.GroupVersionKind())}
 
 	snapshotCR, err = s.controller.Client.AppsV1().ControllerRevisions(s.snapshot.Namespace).Create(context.Background(), snapshotCR, metav1.CreateOptions{})
 	if err != nil && !errors.IsAlreadyExists(err) {

pkg/util/BUILD.bazel

@@ -10,7 +10,9 @@ go_library(
     visibility = ["//visibility:public"],
     deps = [
         "//staging/src/kubevirt.io/api/core/v1:go_default_library",
+        "//staging/src/kubevirt.io/client-go/generated/kubevirt/clientset/versioned/scheme:go_default_library",
         "//staging/src/kubevirt.io/client-go/log:go_default_library",
         "//vendor/k8s.io/apimachinery/pkg/api/resource:go_default_library",
+        "//vendor/k8s.io/apimachinery/pkg/runtime:go_default_library",
     ],
 )

pkg/util/util.go

@@ -9,8 +9,10 @@ import (
 	"strings"
 
 	"k8s.io/apimachinery/pkg/api/resource"
+	"k8s.io/apimachinery/pkg/runtime"
 
 	v1 "kubevirt.io/api/core/v1"
+	generatedscheme "kubevirt.io/client-go/generated/kubevirt/clientset/versioned/scheme"
 	"kubevirt.io/client-go/log"
 )
 
@@ -258,3 +260,17 @@ func GenerateSecureRandomString(n int) (string, error) {
 
 	return string(ret), nil
 }
+
+// GenerateKubeVirtGroupVersionKind ensures a provided object registered with KubeVirts generated schema
+// has GVK set correctly. This is required as client-go continues to return objects without
+// TypeMeta set as set out in the following issue: https://github.com/kubernetes/client-go/issues/413
+func GenerateKubeVirtGroupVersionKind(obj runtime.Object) (runtime.Object, error) {
+	objCopy := obj.DeepCopyObject()
+	gvks, _, err := generatedscheme.Scheme.ObjectKinds(objCopy)
+	if err != nil {
+		return nil, fmt.Errorf("could not get GroupVersionKind for object: %w", err)
+	}
+	objCopy.GetObjectKind().SetGroupVersionKind(gvks[0])
+
+	return objCopy, nil
+}