diff --git a/metrics-server/vendor/k8s.io/apimachinery/pkg/util/mergepatch/util.go b/metrics-server/vendor/k8s.io/apimachinery/pkg/util/mergepatch/util.go
new file mode 100644
index 0000000..9261290
--- /dev/null
+++ b/metrics-server/vendor/k8s.io/apimachinery/pkg/util/mergepatch/util.go
@@ -0,0 +1,133 @@
+/*
+Copyright 2017 The Kubernetes 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 mergepatch
+
+import (
+	"fmt"
+	"reflect"
+
+	"github.com/davecgh/go-spew/spew"
+	"github.com/ghodss/yaml"
+)
+
+// PreconditionFunc asserts that an incompatible change is not present within a patch.
+type PreconditionFunc func(interface{}) bool
+
+// RequireKeyUnchanged returns a precondition function that fails if the provided key
+// is present in the patch (indicating that its value has changed).
+func RequireKeyUnchanged(key string) PreconditionFunc {
+	return func(patch interface{}) bool {
+		patchMap, ok := patch.(map[string]interface{})
+		if !ok {
+			return true
+		}
+
+		// The presence of key means that its value has been changed, so the test fails.
+		_, ok = patchMap[key]
+		return !ok
+	}
+}
+
+// RequireMetadataKeyUnchanged creates a precondition function that fails
+// if the metadata.key is present in the patch (indicating its value
+// has changed).
+func RequireMetadataKeyUnchanged(key string) PreconditionFunc {
+	return func(patch interface{}) bool {
+		patchMap, ok := patch.(map[string]interface{})
+		if !ok {
+			return true
+		}
+		patchMap1, ok := patchMap["metadata"]
+		if !ok {
+			return true
+		}
+		patchMap2, ok := patchMap1.(map[string]interface{})
+		if !ok {
+			return true
+		}
+		_, ok = patchMap2[key]
+		return !ok
+	}
+}
+
+func ToYAMLOrError(v interface{}) string {
+	y, err := toYAML(v)
+	if err != nil {
+		return err.Error()
+	}
+
+	return y
+}
+
+func toYAML(v interface{}) (string, error) {
+	y, err := yaml.Marshal(v)
+	if err != nil {
+		return "", fmt.Errorf("yaml marshal failed:%v\n%v\n", err, spew.Sdump(v))
+	}
+
+	return string(y), nil
+}
+
+// HasConflicts returns true if the left and right JSON interface objects overlap with
+// different values in any key. All keys are required to be strings. Since patches of the
+// same Type have congruent keys, this is valid for multiple patch types. This method
+// supports JSON merge patch semantics.
+//
+// NOTE: Numbers with different types (e.g. int(0) vs int64(0)) will be detected as conflicts.
+//       Make sure the unmarshaling of left and right are consistent (e.g. use the same library).
+func HasConflicts(left, right interface{}) (bool, error) {
+	switch typedLeft := left.(type) {
+	case map[string]interface{}:
+		switch typedRight := right.(type) {
+		case map[string]interface{}:
+			for key, leftValue := range typedLeft {
+				rightValue, ok := typedRight[key]
+				if !ok {
+					continue
+				}
+				if conflict, err := HasConflicts(leftValue, rightValue); err != nil || conflict {
+					return conflict, err
+				}
+			}
+
+			return false, nil
+		default:
+			return true, nil
+		}
+	case []interface{}:
+		switch typedRight := right.(type) {
+		case []interface{}:
+			if len(typedLeft) != len(typedRight) {
+				return true, nil
+			}
+
+			for i := range typedLeft {
+				if conflict, err := HasConflicts(typedLeft[i], typedRight[i]); err != nil || conflict {
+					return conflict, err
+				}
+			}
+
+			return false, nil
+		default:
+			return true, nil
+		}
+	case string, float64, bool, int, int64, nil:
+		return !reflect.DeepEqual(left, right), nil
+	default:
+		return true, fmt.Errorf("unknown type: %v", reflect.TypeOf(left))
+	}
+}