Merge pull request #33250 from ymqytw/edit_before_create

Automatic merge from submit-queue

support editing before creating resource

Support `kubectl create -f config.yaml --edit`
Support editing before creating resource from files, urls and stdin.
The behavior is similar to `kubectl edit`
It won't create anything when edit make no change.

partial: #18064

Based on: #33686 and #33973

```release-note
Support editing before creating resource from files, urls and stdin, e.g. `kubectl create -f config.yaml --edit`
It won't create anything when edit make no change.
```

hack/make-rules/test-cmd.sh

@@ -720,6 +720,25 @@ runTests() {
   # Pre-condition: no POD exists
   create_and_use_new_namespace
   kube::test::get_object_assert pods "{{range.items}}{{$id_field}}:{{end}}" ''
+  ## kubectl create --edit can update the image field of a POD. tmp-editor.sh is a fake editor
+  TEMP=$(mktemp /tmp/tmp-editor-XXXXXXXX.sh)
+  echo -e "#!/bin/bash\n$SED -i \"s/gcr.io\/google_containers\/serve_hostname/nginx/g\" \$1" > ${TEMP}
+  chmod +x ${TEMP}
+  # Command
+  EDITOR=${TEMP} kubectl create --edit -f test/fixtures/doc-yaml/admin/limitrange/valid-pod.yaml "${kube_flags[@]}"
+  # Post-condition: valid-pod POD is created and has image gcr.io/google_containers/serve_hostname
+  kube::test::get_object_assert pods "{{range.items}}{{$id_field}}:{{end}}" 'valid-pod:'
+  kube::test::get_object_assert pods "{{range.items}}{{$image_field}}:{{end}}" 'nginx:'
+  # Clean up
+  rm ${TEMP}
+  kubectl delete pods/valid-pod "${kube_flags[@]}"
+
+  ## kubectl create --edit won't create anything if user makes no changes
+  [ "$(EDITOR=cat kubectl create --edit -f test/fixtures/doc-yaml/admin/limitrange/valid-pod.yaml -o json 2>&1 | grep 'Edit cancelled')" ]
+
+  ## Create valid-pod POD
+  # Pre-condition: no POD exists
+  kube::test::get_object_assert pods "{{range.items}}{{$id_field}}:{{end}}" ''
   # Command
   kubectl create -f test/fixtures/doc-yaml/admin/limitrange/valid-pod.yaml "${kube_flags[@]}"
   # Post-condition: valid-pod POD is created

pkg/kubectl/cmd/cmd.go

@@ -221,7 +221,7 @@ func NewKubectlCommand(f cmdutil.Factory, in io.Reader, out, err io.Writer) *cob
 		{
 			Message: "Basic Commands (Beginner):",
 			Commands: []*cobra.Command{
-				NewCmdCreate(f, out),
+				NewCmdCreate(f, out, err),
 				NewCmdExposeService(f, out),
 				NewCmdRun(f, in, out, err),
 				set.NewCmdSet(f, out, err),

pkg/kubectl/cmd/create.go

@@ -19,6 +19,7 @@ package cmd
 import (
 	"fmt"
 	"io"
+	gruntime "runtime"
 
 	"github.com/spf13/cobra"
 
@@ -41,10 +42,13 @@ var (
 		kubectl create -f ./pod.json
 
 		# Create a pod based on the JSON passed into stdin.
-		cat pod.json | kubectl create -f -`)
+		cat pod.json | kubectl create -f -
+
+		# Edit the data in docker-registry.yaml in JSON using the v1 API format then create the resource using the edited data.
+		kubectl create -f docker-registry.yaml --edit --output-version=v1 -o json`)
 )
 
-func NewCmdCreate(f cmdutil.Factory, out io.Writer) *cobra.Command {
+func NewCmdCreate(f cmdutil.Factory, out, errOut io.Writer) *cobra.Command {
 	options := &resource.FilenameOptions{}
 
 	cmd := &cobra.Command{
@@ -58,8 +62,7 @@ func NewCmdCreate(f cmdutil.Factory, out io.Writer) *cobra.Command {
 				return
 			}
 			cmdutil.CheckErr(ValidateArgs(cmd, args))
-			cmdutil.CheckErr(cmdutil.ValidateOutputArgs(cmd))
+			cmdutil.CheckErr(RunCreate(f, cmd, out, errOut, options))
-			cmdutil.CheckErr(RunCreate(f, cmd, out, options))
 		},
 	}
 
@@ -68,6 +71,8 @@ func NewCmdCreate(f cmdutil.Factory, out io.Writer) *cobra.Command {
 	cmd.MarkFlagRequired("filename")
 	cmdutil.AddValidateFlags(cmd)
 	cmdutil.AddPrinterFlags(cmd)
+	cmd.Flags().Bool("edit", false, "Edit the API resource before creating")
+	cmd.Flags().Bool("windows-line-endings", gruntime.GOOS == "windows", "Only relevant if --edit=true. Use Windows line-endings (default Unix line-endings)")
 	cmdutil.AddApplyAnnotationFlags(cmd)
 	cmdutil.AddRecordFlag(cmd)
 	cmdutil.AddDryRunFlag(cmd)
@@ -91,7 +96,10 @@ func ValidateArgs(cmd *cobra.Command, args []string) error {
 	return nil
 }
 
-func RunCreate(f cmdutil.Factory, cmd *cobra.Command, out io.Writer, options *resource.FilenameOptions) error {
+func RunCreate(f cmdutil.Factory, cmd *cobra.Command, out, errOut io.Writer, options *resource.FilenameOptions) error {
+	if cmdutil.GetFlagBool(cmd, "edit") {
+		return RunEditOnCreate(f, out, errOut, cmd, options)
+	}
 	schema, err := f.Validator(cmdutil.GetFlagBool(cmd, "validate"), cmdutil.GetFlagString(cmd, "schema-cache-dir"))
 	if err != nil {
 		return err
@@ -159,6 +167,10 @@ func RunCreate(f cmdutil.Factory, cmd *cobra.Command, out io.Writer, options *re
 	return nil
 }
 
+func RunEditOnCreate(f cmdutil.Factory, out, errOut io.Writer, cmd *cobra.Command, options *resource.FilenameOptions) error {
+	return runEdit(f, out, errOut, cmd, []string{}, options, EditBeforeCreateMode)
+}
+
 // createAndRefresh creates an object from input info and refreshes info with that object
 func createAndRefresh(info *resource.Info) error {
 	obj, err := resource.NewHelper(info.Client, info.Mapping).Create(info.Namespace, true, info.Object)

pkg/kubectl/cmd/create_test.go

@@ -29,9 +29,10 @@ import (
 func TestExtraArgsFail(t *testing.T) {
 	initTestErrorHandler(t)
 	buf := bytes.NewBuffer([]byte{})
+	errBuf := bytes.NewBuffer([]byte{})
 
 	f, _, _, _ := cmdtesting.NewAPIFactory()
-	c := NewCmdCreate(f, buf)
+	c := NewCmdCreate(f, buf, errBuf)
 	if ValidateArgs(c, []string{"rc"}) == nil {
 		t.Errorf("unexpected non-error")
 	}
@@ -59,8 +60,9 @@ func TestCreateObject(t *testing.T) {
 	}
 	tf.Namespace = "test"
 	buf := bytes.NewBuffer([]byte{})
+	errBuf := bytes.NewBuffer([]byte{})
 
-	cmd := NewCmdCreate(f, buf)
+	cmd := NewCmdCreate(f, buf, errBuf)
 	cmd.Flags().Set("filename", "../../../examples/guestbook/legacy/redis-master-controller.yaml")
 	cmd.Flags().Set("output", "name")
 	cmd.Run(cmd, []string{})
@@ -94,8 +96,9 @@ func TestCreateMultipleObject(t *testing.T) {
 	}
 	tf.Namespace = "test"
 	buf := bytes.NewBuffer([]byte{})
+	errBuf := bytes.NewBuffer([]byte{})
 
-	cmd := NewCmdCreate(f, buf)
+	cmd := NewCmdCreate(f, buf, errBuf)
 	cmd.Flags().Set("filename", "../../../examples/guestbook/legacy/redis-master-controller.yaml")
 	cmd.Flags().Set("filename", "../../../examples/guestbook/frontend-service.yaml")
 	cmd.Flags().Set("output", "name")
@@ -129,8 +132,9 @@ func TestCreateDirectory(t *testing.T) {
 	}
 	tf.Namespace = "test"
 	buf := bytes.NewBuffer([]byte{})
+	errBuf := bytes.NewBuffer([]byte{})
 
-	cmd := NewCmdCreate(f, buf)
+	cmd := NewCmdCreate(f, buf, errBuf)
 	cmd.Flags().Set("filename", "../../../examples/guestbook/legacy")
 	cmd.Flags().Set("output", "name")
 	cmd.Run(cmd, []string{})

pkg/kubectl/cmd/edit.go

@@ -118,12 +118,16 @@ func NewCmdEdit(f cmdutil.Factory, out, errOut io.Writer) *cobra.Command {
 }
 
 func RunEdit(f cmdutil.Factory, out, errOut io.Writer, cmd *cobra.Command, args []string, options *resource.FilenameOptions) error {
+	return runEdit(f, out, errOut, cmd, args, options, NormalEditMode)
+}
+
+func runEdit(f cmdutil.Factory, out, errOut io.Writer, cmd *cobra.Command, args []string, options *resource.FilenameOptions, editMode EditMode) error {
 	o, err := getPrinter(cmd)
 	if err != nil {
 		return err
 	}
 
-	mapper, resourceMapper, r, cmdNamespace, err := getMapperAndResult(f, args, options)
+	mapper, resourceMapper, r, cmdNamespace, err := getMapperAndResult(f, args, options, editMode)
 	if err != nil {
 		return err
 	}
@@ -192,14 +196,15 @@ func RunEdit(f cmdutil.Factory, out, errOut io.Writer, cmd *cobra.Command, args
 			if err != nil {
 				return preservedFile(err, results.file, errOut)
 			}
+			if editMode == NormalEditMode || containsError {
 				if bytes.Equal(stripComments(editedDiff), stripComments(edited)) {
 					// Ugly hack right here. We will hit this either (1) when we try to
 					// save the same changes we tried to save in the previous iteration
 					// which means our changes are invalid or (2) when we exit the second
 					// time. The second case is more usual so we can probably live with it.
 					// TODO: A less hacky fix would be welcome :)
-				fmt.Fprintln(errOut, "Edit cancelled, no valid changes were saved.")
+					return preservedFile(fmt.Errorf("%s", "Edit cancelled, no valid changes were saved."), file, errOut)
-				return nil
+				}
 			}
 
 			// cleanup any file from the previous pass
@@ -229,6 +234,7 @@ func RunEdit(f cmdutil.Factory, out, errOut io.Writer, cmd *cobra.Command, args
 				fmt.Fprintln(errOut, "Edit cancelled, no changes made.")
 				return nil
 			}
+
 			lines, err := hasLines(bytes.NewBuffer(edited))
 			if err != nil {
 				return preservedFile(err, file, errOut)
@@ -271,7 +277,14 @@ func RunEdit(f cmdutil.Factory, out, errOut io.Writer, cmd *cobra.Command, args
 				meta.SetList(updates.Object, mutatedObjects)
 			}
 
+			switch editMode {
+			case NormalEditMode:
 				err = visitToPatch(originalObj, updates, mapper, resourceMapper, encoder, out, errOut, defaultVersion, &results, file)
+			case EditBeforeCreateMode:
+				err = visitToCreate(updates, mapper, resourceMapper, out, errOut, defaultVersion, &results, file)
+			default:
+				err = fmt.Errorf("Not supported edit mode %q", editMode)
+			}
 			if err != nil {
 				return preservedFile(err, results.file, errOut)
 			}
@@ -315,7 +328,8 @@ func getPrinter(cmd *cobra.Command) (*editPrinterOptions, error) {
 			ext:       ".json",
 			addHeader: false,
 		}, nil
-	case "yaml":
+	// If flag -o is not specified, use yaml as default
+	case "yaml", "":
 		return &editPrinterOptions{
 			printer:   &kubectl.YAMLPrinter{},
 			ext:       ".yaml",
@@ -326,13 +340,24 @@ func getPrinter(cmd *cobra.Command) (*editPrinterOptions, error) {
 	}
 }
 
-func getMapperAndResult(f cmdutil.Factory, args []string, options *resource.FilenameOptions) (meta.RESTMapper, *resource.Mapper, *resource.Result, string, error) {
+func getMapperAndResult(f cmdutil.Factory, args []string, options *resource.FilenameOptions, editMode EditMode) (meta.RESTMapper, *resource.Mapper, *resource.Result, string, error) {
 	cmdNamespace, enforceNamespace, err := f.DefaultNamespace()
 	if err != nil {
 		return nil, nil, nil, "", err
 	}
-
+	var mapper meta.RESTMapper
-	mapper, typer := f.Object()
+	var typer runtime.ObjectTyper
+	switch editMode {
+	case NormalEditMode:
+		mapper, typer = f.Object()
+	case EditBeforeCreateMode:
+		mapper, typer, err = f.UnstructuredObject()
+	default:
+		return nil, nil, nil, "", fmt.Errorf("Not supported edit mode %q", editMode)
+	}
+	if err != nil {
+		return nil, nil, nil, "", err
+	}
 	resourceMapper := &resource.Mapper{
 		ObjectTyper:  typer,
 		RESTMapper:   mapper,
@@ -345,14 +370,21 @@ func getMapperAndResult(f cmdutil.Factory, args []string, options *resource.File
 		// compare two different GroupVersions).
 		Decoder: f.Decoder(false),
 	}
-
+	var b *resource.Builder
-	r := resource.NewBuilder(mapper, typer, resource.ClientMapperFunc(f.ClientForMapping), f.Decoder(true)).
+	switch editMode {
-		NamespaceParam(cmdNamespace).DefaultNamespace().
+	case NormalEditMode:
-		FilenameParam(enforceNamespace, options).
+		b = resource.NewBuilder(mapper, typer, resource.ClientMapperFunc(f.ClientForMapping), f.Decoder(true)).
 			ResourceTypeOrNameArgs(true, args...).
+			Latest()
+	case EditBeforeCreateMode:
+		b = resource.NewBuilder(mapper, typer, resource.ClientMapperFunc(f.UnstructuredClientForMapping), runtime.UnstructuredJSONScheme)
+	default:
+		return nil, nil, nil, "", fmt.Errorf("Not supported edit mode %q", editMode)
+	}
+	r := b.NamespaceParam(cmdNamespace).DefaultNamespace().
+		FilenameParam(enforceNamespace, options).
 		ContinueOnError().
 		Flatten().
-		Latest().
 		Do()
 	err = r.Err()
 	if err != nil {
@@ -428,7 +460,7 @@ func visitToPatch(originalObj runtime.Object, updates *resource.Info, mapper met
 		if err != nil {
 			glog.V(4).Infof("Unable to calculate diff, no merge is possible: %v", err)
 			if strategicpatch.IsPreconditionFailed(err) {
-				return preservedFile(nil, file, errOut)
+				return fmt.Errorf("%s", "At least one of apiVersion, kind and name was changed")
 			}
 			return err
 		}
@@ -446,6 +478,19 @@ func visitToPatch(originalObj runtime.Object, updates *resource.Info, mapper met
 	return err
 }
 
+func visitToCreate(updates *resource.Info, mapper meta.RESTMapper, resourceMapper *resource.Mapper, out, errOut io.Writer, defaultVersion unversioned.GroupVersion, results *editResults, file string) error {
+	createVisitor := resource.NewFlattenListVisitor(updates, resourceMapper)
+	err := createVisitor.Visit(func(info *resource.Info, incomingErr error) error {
+		results.version = defaultVersion
+		if err := createAndRefresh(info); err != nil {
+			return err
+		}
+		cmdutil.PrintSuccess(mapper, false, out, info.Mapping.Resource, info.Name, false, "created")
+		return nil
+	})
+	return err
+}
+
 func visitAnnotation(cmd *cobra.Command, f cmdutil.Factory, updates *resource.Info, resourceMapper *resource.Mapper, encoder runtime.Encoder) ([]runtime.Object, error) {
 	mutatedObjects := []runtime.Object{}
 	annotationVisitor := resource.NewFlattenListVisitor(updates, resourceMapper)
@@ -468,6 +513,13 @@ func visitAnnotation(cmd *cobra.Command, f cmdutil.Factory, updates *resource.In
 	return mutatedObjects, err
 }
 
+type EditMode string
+
+const (
+	NormalEditMode       EditMode = "normal_mode"
+	EditBeforeCreateMode EditMode = "edit_before_create_mode"
+)
+
 // editReason preserves a message about the reason this file must be edited again
 type editReason struct {
 	head  string