util: optimize informers transformers

pkg/util/transformer/metadata_transformer.go

@@ -0,0 +1,37 @@
+/*
+Copyright 2022 The Koordinator Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package transformer
+
+import (
+	"fmt"
+
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/client-go/tools/cache"
+)
+
+var _ cache.TransformFunc = PartialMetadataRemoveTransform
+
+// partialMetadataRemoveAll implements a cache.TransformFunc that removes managed
+// fields from PartialObjectMetadata.
+func PartialMetadataRemoveTransform(obj interface{}) (interface{}, error) {
+	partialMeta, ok := obj.(*metav1.PartialObjectMetadata)
+	if !ok {
+		return nil, fmt.Errorf("internal error: cannot cast object %#+v to PartialObjectMetadata", obj)
+	}
+	partialMeta.ManagedFields = nil
+	return partialMeta, nil
+}

pkg/util/transformer/metadata_transformer_test.go

@@ -0,0 +1,66 @@
+/*
+Copyright 2022 The Koordinator Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package transformer
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+)
+
+func TestTransformMetadata(t *testing.T) {
+	tests := []struct {
+		name    string
+		pod     *metav1.PartialObjectMetadata
+		wantPod *metav1.PartialObjectMetadata
+	}{
+		{
+			name: "normal pod metadata transform",
+			pod: &metav1.PartialObjectMetadata{
+				TypeMeta: metav1.TypeMeta{
+					Kind:       "Pod",
+					APIVersion: "v1",
+				},
+				ObjectMeta: metav1.ObjectMeta{
+					Name:          "name",
+					Namespace:     "ns",
+					ManagedFields: []metav1.ManagedFieldsEntry{},
+				},
+			},
+
+			wantPod: &metav1.PartialObjectMetadata{
+				TypeMeta: metav1.TypeMeta{
+					Kind:       "Pod",
+					APIVersion: "v1",
+				},
+				ObjectMeta: metav1.ObjectMeta{
+					Name:          "name",
+					Namespace:     "ns",
+					ManagedFields: nil,
+				},
+			},
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			obj, err := PartialMetadataRemoveTransform(tt.pod)
+			assert.NoError(t, err)
+			assert.Equal(t, tt.wantPod, obj)
+		})
+	}
+}

pkg/util/transformer/transformers.go

@@ -45,5 +45,9 @@ func SetupTransformers(informerFactory informers.SharedInformerFactory, koordInf
 		if err := informer.Informer().SetTransform(transformFn); err != nil {
 			klog.Fatalf("Failed to SetTransform in informer, resource: %v, err: %v", resource, err)
 		}
+		// clean up partial metadata
+		if err := informer.Informer().SetTransform(PartialMetadataRemoveTransform); err != nil {
+			klog.Fatalf("Failed to PartialMetadataRemoveTransform in informer, resource: %v, err: %v", resource, err)
+		}
 	}
 }