Refactor diff/prune

This PR does some refactors for diff/prune;

- GetRESTMappings takes value array instead reference
- Move getObjectName into diff instead prune
- License, etc. changes

staging/src/k8s.io/kubectl/pkg/cmd/apply/apply.go

@@ -21,9 +21,8 @@ import (
 	"io"
 	"net/http"
 
-	"k8s.io/kubectl/pkg/util/prune"
-
 	"github.com/spf13/cobra"
+
 	corev1 "k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/api/errors"
 	"k8s.io/apimachinery/pkg/api/meta"
@@ -44,6 +43,7 @@ import (
 	"k8s.io/kubectl/pkg/util"
 	"k8s.io/kubectl/pkg/util/i18n"
 	"k8s.io/kubectl/pkg/util/openapi"
+	"k8s.io/kubectl/pkg/util/prune"
 	"k8s.io/kubectl/pkg/util/templates"
 	"k8s.io/kubectl/pkg/validation"
 )

staging/src/k8s.io/kubectl/pkg/cmd/apply/prune.go

@@ -21,8 +21,6 @@ import (
 	"fmt"
 	"io"
 
-	"k8s.io/kubectl/pkg/util/prune"
-
 	corev1 "k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/api/meta"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
@@ -30,6 +28,7 @@ import (
 	"k8s.io/cli-runtime/pkg/printers"
 	"k8s.io/client-go/dynamic"
 	cmdutil "k8s.io/kubectl/pkg/cmd/util"
+	"k8s.io/kubectl/pkg/util/prune"
 )
 
 type pruner struct {
@@ -71,7 +70,7 @@ func newPruner(o *ApplyOptions) pruner {
 
 func (p *pruner) pruneAll(o *ApplyOptions) error {
 
-	namespacedRESTMappings, nonNamespacedRESTMappings, err := prune.GetRESTMappings(o.Mapper, &(o.PruneResources))
+	namespacedRESTMappings, nonNamespacedRESTMappings, err := prune.GetRESTMappings(o.Mapper, o.PruneResources)
 	if err != nil {
 		return fmt.Errorf("error retrieving RESTMappings to prune: %v", err)
 	}

staging/src/k8s.io/kubectl/pkg/cmd/diff/diff.go

@@ -25,8 +25,6 @@ import (
 	"regexp"
 	"strings"
 
-	"k8s.io/kubectl/pkg/util/prune"
-
 	"github.com/jonboulle/clockwork"
 	"github.com/spf13/cobra"
 	"k8s.io/apimachinery/pkg/api/errors"
@@ -46,6 +44,7 @@ import (
 	"k8s.io/kubectl/pkg/util"
 	"k8s.io/kubectl/pkg/util/i18n"
 	"k8s.io/kubectl/pkg/util/openapi"
+	"k8s.io/kubectl/pkg/util/prune"
 	"k8s.io/kubectl/pkg/util/templates"
 	"k8s.io/utils/exec"
 	"sigs.k8s.io/yaml"
@@ -173,7 +172,7 @@ func NewCmdDiff(f cmdutil.Factory, streams genericclioptions.IOStreams) *cobra.C
 
 	usage := "contains the configuration to diff"
 	cmd.Flags().StringVarP(&options.Selector, "selector", "l", options.Selector, "Selector (label query) to filter on, supports '=', '==', and '!='.(e.g. -l key1=value1,key2=value2)")
-	cmd.Flags().StringArray("prunewhitelist", []string{}, "Overwrite the default whitelist with <group/version/kind> for --prune")
+	cmd.Flags().StringArray("prune-allowlist", []string{}, "Overwrite the default whitelist with <group/version/kind> for --prune")
 	cmd.Flags().Bool("prune", false, "Include resources that would be deleted by pruning. Can be used with -l and default shows all resources would be pruned")
 	cmdutil.AddFilenameOptionFlags(cmd, &options.FilenameOptions, usage)
 	cmdutil.AddServerSideApplyFlags(cmd)
@@ -653,7 +652,7 @@ func (o *DiffOptions) Complete(f cmdutil.Factory, cmd *cobra.Command) error {
 			return err
 		}
 
-		resources, err := prune.ParseResources(mapper, cmdutil.GetFlagStringArray(cmd, "prunewhitelist"))
+		resources, err := prune.ParseResources(mapper, cmdutil.GetFlagStringArray(cmd, "prune-allowlist"))
 		if err != nil {
 			return err
 		}
@@ -749,7 +748,7 @@ func (o *DiffOptions) Run() error {
 		// Print pruned objects into old file and thus, diff
 		// command will show them as pruned.
 		for _, p := range prunedObjs {
-			name, err := o.pruner.GetObjectName(p)
+			name, err := getObjectName(p)
 			if err != nil {
 				klog.Warningf("pruning failed and object name could not be retrieved: %v", err)
 				continue
@@ -766,3 +765,25 @@ func (o *DiffOptions) Run() error {
 
 	return differ.Run(o.Diff)
 }
+
+func getObjectName(obj runtime.Object) (string, error) {
+	gvk := obj.GetObjectKind().GroupVersionKind()
+	metadata, err := meta.Accessor(obj)
+	if err != nil {
+		return "", err
+	}
+	name := metadata.GetName()
+	ns := metadata.GetNamespace()
+
+	group := ""
+	if gvk.Group != "" {
+		group = fmt.Sprintf("%v.", gvk.Group)
+	}
+	return group + fmt.Sprintf(
+		"%v.%v.%v.%v",
+		gvk.Version,
+		gvk.Kind,
+		ns,
+		name,
+	), nil
+}

staging/src/k8s.io/kubectl/pkg/cmd/diff/prune.go

@@ -1,5 +1,5 @@
 /*
-Copyright 2019 The Kubernetes Authors.
+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.
@@ -20,17 +20,14 @@ import (
 	"context"
 	"fmt"
 
-	"k8s.io/cli-runtime/pkg/resource"
-
-	"k8s.io/apimachinery/pkg/runtime"
-
-	"k8s.io/kubectl/pkg/util/prune"
-
 	corev1 "k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/api/meta"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/apimachinery/pkg/util/sets"
+	"k8s.io/cli-runtime/pkg/resource"
 	"k8s.io/client-go/dynamic"
+	"k8s.io/kubectl/pkg/util/prune"
 )
 
 type pruner struct {
@@ -55,7 +52,7 @@ func newPruner(dc dynamic.Interface, m meta.RESTMapper, r []prune.Resource) *pru
 
 func (p *pruner) pruneAll() ([]runtime.Object, error) {
 	var allPruned []runtime.Object
-	namespacedRESTMappings, nonNamespacedRESTMappings, err := prune.GetRESTMappings(p.mapper, &(p.resources))
+	namespacedRESTMappings, nonNamespacedRESTMappings, err := prune.GetRESTMappings(p.mapper, p.resources)
 	if err != nil {
 		return allPruned, fmt.Errorf("error retrieving RESTMappings to prune: %v", err)
 	}
@@ -115,28 +112,6 @@ func (p *pruner) prune(namespace string, mapping *meta.RESTMapping) ([]runtime.O
 	return pobjs, nil
 }
 
-func (p *pruner) GetObjectName(obj runtime.Object) (string, error) {
-	gvk := obj.GetObjectKind().GroupVersionKind()
-	metadata, err := meta.Accessor(obj)
-	if err != nil {
-		return "", err
-	}
-	name := metadata.GetName()
-	ns := metadata.GetNamespace()
-
-	group := ""
-	if gvk.Group != "" {
-		group = fmt.Sprintf("%v.", gvk.Group)
-	}
-	return group + fmt.Sprintf(
-		"%v.%v.%v.%v",
-		gvk.Version,
-		gvk.Kind,
-		ns,
-		name,
-	), nil
-}
-
 // MarkVisited marks visited namespaces and uids
 func (p *pruner) MarkVisited(info *resource.Info) {
 	if info.Namespaced() {

staging/src/k8s.io/kubectl/pkg/util/prune/prune.go

@@ -35,10 +35,10 @@ func (pr Resource) String() string {
 	return fmt.Sprintf("%v/%v, Kind=%v, Namespaced=%v", pr.group, pr.version, pr.kind, pr.namespaced)
 }
 
-func GetRESTMappings(mapper meta.RESTMapper, pruneResources *[]Resource) (namespaced, nonNamespaced []*meta.RESTMapping, err error) {
+func GetRESTMappings(mapper meta.RESTMapper, pruneResources []Resource) (namespaced, nonNamespaced []*meta.RESTMapping, err error) {
-	if len(*pruneResources) == 0 {
+	if len(pruneResources) == 0 {
 		// default allowlist
-		*pruneResources = []Resource{
+		pruneResources = []Resource{
 			{"", "v1", "ConfigMap", true},
 			{"", "v1", "Endpoints", true},
 			{"", "v1", "Namespace", false},
@@ -58,7 +58,7 @@ func GetRESTMappings(mapper meta.RESTMapper, pruneResources *[]Resource) (namesp
 		}
 	}
 
-	for _, resource := range *pruneResources {
+	for _, resource := range pruneResources {
 		addedMapping, err := mapper.RESTMapping(schema.GroupKind{Group: resource.group, Kind: resource.kind}, resource.version)
 		if err != nil {
 			return nil, nil, fmt.Errorf("invalid resource %v: %v", resource, err)

staging/src/k8s.io/kubectl/pkg/util/prune/prune_test.go

@@ -49,14 +49,14 @@ func (m *testRESTMapper) RESTMapping(gk schema.GroupKind, versions ...string) (*
 func TestGetRESTMappings(t *testing.T) {
 	tests := []struct {
 		mapper      *testRESTMapper
-		pr          *[]Resource
+		pr          []Resource
 		expectedns  int
 		expectednns int
 		expectederr error
 	}{
 		{
 			mapper:      &testRESTMapper{},
-			pr:          &[]Resource{},
+			pr:          []Resource{},
 			expectedns:  14,
 			expectednns: 2,
 			expectederr: nil,