move Kubernetes helper code into separate file

The goal is to have only "legacy" code in klog.go.

helpers.go

@@ -0,0 +1,94 @@
+/*
+Copyright 2021 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 klog
+
+import (
+	"fmt"
+	"reflect"
+
+	"github.com/go-logr/logr"
+)
+
+// ObjectRef references a kubernetes object
+type ObjectRef struct {
+	Name      string `json:"name"`
+	Namespace string `json:"namespace,omitempty"`
+}
+
+func (ref ObjectRef) String() string {
+	if ref.Namespace != "" {
+		return fmt.Sprintf("%s/%s", ref.Namespace, ref.Name)
+	}
+	return ref.Name
+}
+
+// MarshalLog ensures that loggers with support for structured output will log
+// as a struct by removing the String method via a custom type.
+func (ref ObjectRef) MarshalLog() interface{} {
+	type or ObjectRef
+	return or(ref)
+}
+
+var _ logr.Marshaler = ObjectRef{}
+
+// KMetadata is a subset of the kubernetes k8s.io/apimachinery/pkg/apis/meta/v1.Object interface
+// this interface may expand in the future, but will always be a subset of the
+// kubernetes k8s.io/apimachinery/pkg/apis/meta/v1.Object interface
+type KMetadata interface {
+	GetName() string
+	GetNamespace() string
+}
+
+// KObj returns ObjectRef from ObjectMeta
+func KObj(obj KMetadata) ObjectRef {
+	if obj == nil {
+		return ObjectRef{}
+	}
+	if val := reflect.ValueOf(obj); val.Kind() == reflect.Ptr && val.IsNil() {
+		return ObjectRef{}
+	}
+
+	return ObjectRef{
+		Name:      obj.GetName(),
+		Namespace: obj.GetNamespace(),
+	}
+}
+
+// KRef returns ObjectRef from name and namespace
+func KRef(namespace, name string) ObjectRef {
+	return ObjectRef{
+		Name:      name,
+		Namespace: namespace,
+	}
+}
+
+// KObjs returns slice of ObjectRef from an slice of ObjectMeta
+func KObjs(arg interface{}) []ObjectRef {
+	s := reflect.ValueOf(arg)
+	if s.Kind() != reflect.Slice {
+		return nil
+	}
+	objectRefs := make([]ObjectRef, 0, s.Len())
+	for i := 0; i < s.Len(); i++ {
+		if v, ok := s.Index(i).Interface().(KMetadata); ok {
+			objectRefs = append(objectRefs, KObj(v))
+		} else {
+			return nil
+		}
+	}
+	return objectRefs
+}

klog.go

@@ -81,7 +81,6 @@ import (
 	"math"
 	"os"
 	"path/filepath"
-	"reflect"
 	"runtime"
 	"strconv"
 	"strings"
@@ -1536,73 +1535,3 @@ type LogFilter interface {
 func SetLogFilter(filter LogFilter) {
 	logging.filter = filter
 }
-
-// ObjectRef references a kubernetes object
-type ObjectRef struct {
-	Name      string `json:"name"`
-	Namespace string `json:"namespace,omitempty"`
-}
-
-func (ref ObjectRef) String() string {
-	if ref.Namespace != "" {
-		return fmt.Sprintf("%s/%s", ref.Namespace, ref.Name)
-	}
-	return ref.Name
-}
-
-// MarshalLog ensures that loggers with support for structured output will log
-// as a struct by removing the String method via a custom type.
-func (ref ObjectRef) MarshalLog() interface{} {
-	type or ObjectRef
-	return or(ref)
-}
-
-var _ logr.Marshaler = ObjectRef{}
-
-// KMetadata is a subset of the kubernetes k8s.io/apimachinery/pkg/apis/meta/v1.Object interface
-// this interface may expand in the future, but will always be a subset of the
-// kubernetes k8s.io/apimachinery/pkg/apis/meta/v1.Object interface
-type KMetadata interface {
-	GetName() string
-	GetNamespace() string
-}
-
-// KObj returns ObjectRef from ObjectMeta
-func KObj(obj KMetadata) ObjectRef {
-	if obj == nil {
-		return ObjectRef{}
-	}
-	if val := reflect.ValueOf(obj); val.Kind() == reflect.Ptr && val.IsNil() {
-		return ObjectRef{}
-	}
-
-	return ObjectRef{
-		Name:      obj.GetName(),
-		Namespace: obj.GetNamespace(),
-	}
-}
-
-// KRef returns ObjectRef from name and namespace
-func KRef(namespace, name string) ObjectRef {
-	return ObjectRef{
-		Name:      name,
-		Namespace: namespace,
-	}
-}
-
-// KObjs returns slice of ObjectRef from an slice of ObjectMeta
-func KObjs(arg interface{}) []ObjectRef {
-	s := reflect.ValueOf(arg)
-	if s.Kind() != reflect.Slice {
-		return nil
-	}
-	objectRefs := make([]ObjectRef, 0, s.Len())
-	for i := 0; i < s.Len(); i++ {
-		if v, ok := s.Index(i).Interface().(KMetadata); ok {
-			objectRefs = append(objectRefs, KObj(v))
-		} else {
-			return nil
-		}
-	}
-	return objectRefs
-}