add --dry-run opt to kubectl set image

This patch adds a `--dry-run` option to `kubectl set image...`

pkg/kubectl/cmd/set/BUILD

@@ -36,7 +36,10 @@ go_library(
 
 go_test(
     name = "go_default_test",
-    srcs = ["set_image_test.go"],
+    srcs = [
+        "set_image_test.go",
+        "set_test.go",
+    ],
     data = [
         "//examples:config",
     ],
@@ -50,5 +53,6 @@ go_test(
         "//pkg/kubectl/cmd/testing:go_default_library",
         "//pkg/kubectl/cmd/util:go_default_library",
         "//pkg/kubectl/resource:go_default_library",
+        "//vendor:github.com/spf13/cobra",
     ],
 )

pkg/kubectl/cmd/set/set_image.go

@@ -42,9 +42,11 @@ type ImageOptions struct {
 	Selector    string
 	Out         io.Writer
 	Err         io.Writer
+	DryRun      bool
 	ShortOutput bool
 	All         bool
 	Record      bool
+	Output      string
 	ChangeCause string
 	Local       bool
 	Cmd         *cobra.Command
@@ -104,6 +106,7 @@ func NewCmdImage(f cmdutil.Factory, out, err io.Writer) *cobra.Command {
 	cmd.Flags().StringVarP(&options.Selector, "selector", "l", "", "Selector (label query) to filter on, supports '=', '==', and '!='.")
 	cmd.Flags().BoolVar(&options.Local, "local", false, "If true, set image will NOT contact api-server but run locally.")
 	cmdutil.AddRecordFlag(cmd)
+	cmdutil.AddDryRunFlag(cmd)
 	return cmd
 }
 
@@ -115,6 +118,8 @@ func (o *ImageOptions) Complete(f cmdutil.Factory, cmd *cobra.Command, args []st
 	o.Record = cmdutil.GetRecordFlag(cmd)
 	o.ChangeCause = f.Command()
 	o.PrintObject = f.PrintObject
+	o.DryRun = cmdutil.GetDryRunFlag(cmd)
+	o.Output = cmdutil.GetFlagString(cmd, "output")
 	o.Cmd = cmd
 
 	cmdNamespace, enforceNamespace, err := f.DefaultNamespace()
@@ -198,7 +203,7 @@ func (o *ImageOptions) Run() error {
 			continue
 		}
 
-		if o.Local {
+		if o.PrintObject != nil && (o.Local || o.DryRun) {
 			return o.PrintObject(o.Cmd, o.Mapper, info.Object, o.Out)
 		}
 
@@ -220,7 +225,11 @@ func (o *ImageOptions) Run() error {
 		}
 
 		info.Refresh(obj, true)
-		cmdutil.PrintSuccess(o.Mapper, o.ShortOutput, o.Out, info.Mapping.Resource, info.Name, false, "image updated")
+
+		if len(o.Output) > 0 {
+			return o.PrintObject(o.Cmd, o.Mapper, obj, o.Out)
+		}
+		cmdutil.PrintSuccess(o.Mapper, o.ShortOutput, o.Out, info.Mapping.Resource, info.Name, o.DryRun, "image updated")
 	}
 	return utilerrors.NewAggregate(allErrs)
 }

pkg/kubectl/cmd/set/set_test.go

@@ -0,0 +1,47 @@
+/*
+Copyright 2016 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 set
+
+import (
+	"bytes"
+	"testing"
+
+	"github.com/spf13/cobra"
+
+	clientcmdutil "k8s.io/kubernetes/pkg/kubectl/cmd/util"
+)
+
+func TestLocalAndDryRunFlags(t *testing.T) {
+	out := &bytes.Buffer{}
+	errout := &bytes.Buffer{}
+	f := clientcmdutil.NewFactory(nil)
+	setCmd := NewCmdSet(f, out, errout)
+	ensureLocalAndDryRunFlagsOnChildren(t, setCmd, "")
+}
+
+func ensureLocalAndDryRunFlagsOnChildren(t *testing.T, c *cobra.Command, prefix string) {
+	for _, cmd := range c.Commands() {
+		name := prefix + cmd.Name()
+		if localFlag := cmd.Flag("local"); localFlag == nil {
+			t.Errorf("Command %s does not implement the --local flag", name)
+		}
+		if dryRunFlag := cmd.Flag("dry-run"); dryRunFlag == nil {
+			t.Errorf("Command %s does not implement the --dry-run flag", name)
+		}
+		ensureLocalAndDryRunFlagsOnChildren(t, cmd, name+".")
+	}
+}