Fix version converter

staging/src/k8s.io/apiserver/pkg/endpoints/handlers/fieldmanager/fieldmanager.go

@@ -72,7 +72,7 @@ func NewCRDFieldManager(objectConverter runtime.ObjectConvertor, objectDefaulter
 		groupVersion:    gv,
 		hubVersion:      hub,
 		updater: merge.Updater{
-			Converter: internal.NewVersionConverter(internal.DeducedTypeConverter{}, objectConverter, hub),
+			Converter: internal.NewCRDVersionConverter(internal.DeducedTypeConverter{}, objectConverter, hub),
 		},
 	}
 }

staging/src/k8s.io/apiserver/pkg/endpoints/handlers/fieldmanager/internal/versionconverter.go

@@ -17,8 +17,6 @@ limitations under the License.
 package internal
 
 import (
-	"fmt"
-
 	"k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/apimachinery/pkg/runtime/schema"
 	"sigs.k8s.io/structured-merge-diff/fieldpath"
@@ -31,7 +29,7 @@ import (
 type versionConverter struct {
 	typeConverter   TypeConverter
 	objectConvertor runtime.ObjectConvertor
-	hubVersion      schema.GroupVersion
+	hubGetter       func(from schema.GroupVersion) schema.GroupVersion
 }
 
 var _ merge.Converter = &versionConverter{}
@@ -41,7 +39,23 @@ func NewVersionConverter(t TypeConverter, o runtime.ObjectConvertor, h schema.Gr
 	return &versionConverter{
 		typeConverter:   t,
 		objectConvertor: o,
-		hubVersion:      h,
+		hubGetter: func(from schema.GroupVersion) schema.GroupVersion {
+			return schema.GroupVersion{
+				Group:   from.Group,
+				Version: h.Version,
+			}
+		},
+	}
+}
+
+// NewCRDVersionConverter builds a VersionConverter for CRDs from a TypeConverter and an ObjectConvertor.
+func NewCRDVersionConverter(t TypeConverter, o runtime.ObjectConvertor, h schema.GroupVersion) merge.Converter {
+	return &versionConverter{
+		typeConverter:   t,
+		objectConvertor: o,
+		hubGetter: func(from schema.GroupVersion) schema.GroupVersion {
+			return h
+		},
 	}
 }
 
@@ -60,22 +74,21 @@ func (v *versionConverter) Convert(object typed.TypedValue, version fieldpath.AP
 	}
 
 	// If attempting to convert to the same version as we already have, just return it.
-	if objectToConvert.GetObjectKind().GroupVersionKind().GroupVersion() == groupVersion {
+	fromVersion := objectToConvert.GetObjectKind().GroupVersionKind().GroupVersion()
+	if fromVersion == groupVersion {
 		return object, nil
 	}
 
 	// Convert to internal
-	internalObject, err := v.objectConvertor.ConvertToVersion(objectToConvert, v.hubVersion)
+	internalObject, err := v.objectConvertor.ConvertToVersion(objectToConvert, v.hubGetter(fromVersion))
 	if err != nil {
-		return object, fmt.Errorf("failed to convert object (%v to %v): %v",
-			objectToConvert.GetObjectKind().GroupVersionKind(), v.hubVersion, err)
+		return object, err
 	}
 
 	// Convert the object into the target version
 	convertedObject, err := v.objectConvertor.ConvertToVersion(internalObject, groupVersion)
 	if err != nil {
-		return object, fmt.Errorf("failed to convert object (%v to %v): %v",
-			internalObject.GetObjectKind().GroupVersionKind(), groupVersion, err)
+		return object, err
 	}
 
 	// Convert the object back to a smd typed value and return it.