Custom resource definition

Co-authored-by: Mathieu Lonjaret <mathieu.lonjaret@gmail.com>

vendor/k8s.io/apimachinery/pkg/runtime/serializer/versioning/versioning.go

@@ -19,6 +19,7 @@ package versioning
 import (
 	"io"
 
+	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
 	"k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/apimachinery/pkg/runtime/schema"
 )
@@ -166,9 +167,27 @@ func (c *codec) Decode(data []byte, defaultGVK *schema.GroupVersionKind, into ru
 // Encode ensures the provided object is output in the appropriate group and version, invoking
 // conversion if necessary. Unversioned objects (according to the ObjectTyper) are output as is.
 func (c *codec) Encode(obj runtime.Object, w io.Writer) error {
-	switch obj.(type) {
-	case *runtime.Unknown, runtime.Unstructured:
+	switch obj := obj.(type) {
+	case *runtime.Unknown:
 		return c.encoder.Encode(obj, w)
+	case runtime.Unstructured:
+		// An unstructured list can contain objects of multiple group version kinds. don't short-circuit just
+		// because the top-level type matches our desired destination type. actually send the object to the converter
+		// to give it a chance to convert the list items if needed.
+		if _, ok := obj.(*unstructured.UnstructuredList); !ok {
+			// avoid conversion roundtrip if GVK is the right one already or is empty (yes, this is a hack, but the old behaviour we rely on in kubectl)
+			objGVK := obj.GetObjectKind().GroupVersionKind()
+			if len(objGVK.Version) == 0 {
+				return c.encoder.Encode(obj, w)
+			}
+			targetGVK, ok := c.encodeVersion.KindForGroupVersionKinds([]schema.GroupVersionKind{objGVK})
+			if !ok {
+				return runtime.NewNotRegisteredGVKErrForTarget(objGVK, c.encodeVersion)
+			}
+			if targetGVK == objGVK {
+				return c.encoder.Encode(obj, w)
+			}
+		}
 	}
 
 	gvks, isUnversioned, err := c.typer.ObjectKinds(obj)