update default run function for sub-commands

pkg/kubectl/cmd/cmd.go

@@ -239,7 +239,7 @@ func NewKubectlCommand(f cmdutil.Factory, in io.Reader, out, err io.Writer) *cob
 		{
 			Message: "Deploy Commands:",
 			Commands: []*cobra.Command{
-				rollout.NewCmdRollout(f, out),
+				rollout.NewCmdRollout(f, out, err),
 				NewCmdRollingUpdate(f, out),
 				NewCmdScale(f, out),
 				NewCmdAutoscale(f, out),
@@ -249,7 +249,7 @@ func NewKubectlCommand(f cmdutil.Factory, in io.Reader, out, err io.Writer) *cob
 			Message: "Cluster Management Commands:",
 			Commands: []*cobra.Command{
 				NewCmdClusterInfo(f, out),
-				NewCmdTop(f, out),
+				NewCmdTop(f, out, err),
 				NewCmdCordon(f, out),
 				NewCmdUncordon(f, out),
 				NewCmdDrain(f, out),
@@ -304,7 +304,7 @@ func NewKubectlCommand(f cmdutil.Factory, in io.Reader, out, err io.Writer) *cob
 		)
 	}
 
-	cmds.AddCommand(cmdconfig.NewCmdConfig(clientcmd.NewDefaultPathOptions(), out))
+	cmds.AddCommand(cmdconfig.NewCmdConfig(clientcmd.NewDefaultPathOptions(), out, err))
 	cmds.AddCommand(NewCmdVersion(f, out))
 	cmds.AddCommand(NewCmdApiVersions(f, out))
 	cmds.AddCommand(NewCmdOptions(out))

pkg/kubectl/cmd/config/config.go

@@ -25,10 +25,11 @@ import (
 
 	"k8s.io/kubernetes/pkg/client/unversioned/clientcmd"
 	"k8s.io/kubernetes/pkg/kubectl/cmd/templates"
+	cmdutil "k8s.io/kubernetes/pkg/kubectl/cmd/util"
 )
 
 // NewCmdConfig creates a command object for the "config" action, and adds all child commands to it.
-func NewCmdConfig(pathOptions *clientcmd.PathOptions, out io.Writer) *cobra.Command {
+func NewCmdConfig(pathOptions *clientcmd.PathOptions, out, errOut io.Writer) *cobra.Command {
 	if len(pathOptions.ExplicitFileFlag) == 0 {
 		pathOptions.ExplicitFileFlag = clientcmd.RecommendedConfigPathFlag
 	}
@@ -44,9 +45,7 @@ func NewCmdConfig(pathOptions *clientcmd.PathOptions, out io.Writer) *cobra.Comm
 			1. If the --` + pathOptions.ExplicitFileFlag + ` flag is set, then only that file is loaded.  The flag may only be set once and no merging takes place.
 			2. If $` + pathOptions.EnvVar + ` environment variable is set, then it is used a list of paths (normal path delimitting rules for your system).  These paths are merged.  When a value is modified, it is modified in the file that defines the stanza.  When a value is created, it is created in the first file that exists.  If no files in the chain exist, then it creates the last file in the list.
 			3. Otherwise, ` + path.Join("${HOME}", pathOptions.GlobalFileSubpath) + ` is used and no merging takes place.`),
-		Run: func(cmd *cobra.Command, args []string) {
-			cmd.Help()
-		},
+		Run: cmdutil.DefaultSubCommandRun(errOut),
 	}
 
 	// file paths are common to all sub commands

pkg/kubectl/cmd/config/config_test.go

@@ -770,7 +770,7 @@ func testConfigCommand(args []string, startingConfig clientcmdapi.Config, t *tes
 
 	buf := bytes.NewBuffer([]byte{})
 
-	cmd := NewCmdConfig(clientcmd.NewDefaultPathOptions(), buf)
+	cmd := NewCmdConfig(clientcmd.NewDefaultPathOptions(), buf, buf)
 	cmd.SetArgs(argsToUse)
 	cmd.Execute()
 

pkg/kubectl/cmd/create.go

@@ -58,7 +58,8 @@ func NewCmdCreate(f cmdutil.Factory, out, errOut io.Writer) *cobra.Command {
 		Example: create_example,
 		Run: func(cmd *cobra.Command, args []string) {
 			if cmdutil.IsFilenameEmpty(options.Filenames) {
-				cmd.Help()
+				defaultRunFunc := cmdutil.DefaultSubCommandRun(errOut)
+				defaultRunFunc(cmd, args)
 				return
 			}
 			cmdutil.CheckErr(ValidateArgs(cmd, args))
@@ -81,10 +82,10 @@ func NewCmdCreate(f cmdutil.Factory, out, errOut io.Writer) *cobra.Command {
 	// create subcommands
 	cmd.AddCommand(NewCmdCreateNamespace(f, out))
 	cmd.AddCommand(NewCmdCreateQuota(f, out))
-	cmd.AddCommand(NewCmdCreateSecret(f, out))
+	cmd.AddCommand(NewCmdCreateSecret(f, out, errOut))
 	cmd.AddCommand(NewCmdCreateConfigMap(f, out))
 	cmd.AddCommand(NewCmdCreateServiceAccount(f, out))
-	cmd.AddCommand(NewCmdCreateService(f, out))
+	cmd.AddCommand(NewCmdCreateService(f, out, errOut))
 	cmd.AddCommand(NewCmdCreateDeployment(f, out))
 	return cmd
 }

pkg/kubectl/cmd/create_secret.go

@@ -28,14 +28,12 @@ import (
 )
 
 // NewCmdCreateSecret groups subcommands to create various types of secrets
-func NewCmdCreateSecret(f cmdutil.Factory, cmdOut io.Writer) *cobra.Command {
+func NewCmdCreateSecret(f cmdutil.Factory, cmdOut, errOut io.Writer) *cobra.Command {
 	cmd := &cobra.Command{
 		Use:   "secret",
 		Short: "Create a secret using specified subcommand",
 		Long:  "Create a secret using specified subcommand.",
-		Run: func(cmd *cobra.Command, args []string) {
-			cmd.Help()
-		},
+		Run:   cmdutil.DefaultSubCommandRun(errOut),
 	}
 	cmd.AddCommand(NewCmdCreateSecretDockerRegistry(f, cmdOut))
 	cmd.AddCommand(NewCmdCreateSecretTLS(f, cmdOut))

pkg/kubectl/cmd/create_service.go

@@ -29,15 +29,13 @@ import (
 )
 
 // NewCmdCreateService is a macro command to create a new service
-func NewCmdCreateService(f cmdutil.Factory, cmdOut io.Writer) *cobra.Command {
+func NewCmdCreateService(f cmdutil.Factory, cmdOut, errOut io.Writer) *cobra.Command {
 	cmd := &cobra.Command{
 		Use:     "service",
 		Aliases: []string{"svc"},
 		Short:   "Create a service using specified subcommand.",
 		Long:    "Create a service using specified subcommand.",
-		Run: func(cmd *cobra.Command, args []string) {
-			cmd.Help()
-		},
+		Run:     cmdutil.DefaultSubCommandRun(errOut),
 	}
 	cmd.AddCommand(NewCmdCreateServiceClusterIP(f, cmdOut))
 	cmd.AddCommand(NewCmdCreateServiceNodePort(f, cmdOut))

pkg/kubectl/cmd/rollout/rollout.go

@@ -39,16 +39,14 @@ var (
 		`)
 )
 
-func NewCmdRollout(f cmdutil.Factory, out io.Writer) *cobra.Command {
+func NewCmdRollout(f cmdutil.Factory, out, errOut io.Writer) *cobra.Command {
 
 	cmd := &cobra.Command{
 		Use:     "rollout SUBCOMMAND",
 		Short:   "Manage a deployment rollout",
 		Long:    rollout_long,
 		Example: rollout_example,
-		Run: func(cmd *cobra.Command, args []string) {
-			cmd.Help()
-		},
+		Run:     cmdutil.DefaultSubCommandRun(errOut),
 	}
 	// subcommands
 	cmd.AddCommand(NewCmdRolloutHistory(f, out))

pkg/kubectl/cmd/set/set.go

@@ -36,9 +36,7 @@ func NewCmdSet(f cmdutil.Factory, out, err io.Writer) *cobra.Command {
 		Use:   "set SUBCOMMAND",
 		Short: "Set specific features on objects",
 		Long:  set_long,
-		Run: func(cmd *cobra.Command, args []string) {
-			cmd.Help()
-		},
+		Run:   cmdutil.DefaultSubCommandRun(err),
 	}
 
 	// add subcommands

pkg/kubectl/cmd/top.go

@@ -35,18 +35,12 @@ var (
 		The top command allows you to see the resource consumption for nodes or pods.`)
 )
 
-func NewCmdTop(f cmdutil.Factory, out io.Writer) *cobra.Command {
-	options := &TopOptions{}
-
+func NewCmdTop(f cmdutil.Factory, out, errOut io.Writer) *cobra.Command {
 	cmd := &cobra.Command{
 		Use:   "top",
 		Short: "Display Resource (CPU/Memory/Storage) usage",
 		Long:  topLong,
-		Run: func(cmd *cobra.Command, args []string) {
-			if err := options.RunTop(f, cmd, args, out); err != nil {
-				cmdutil.CheckErr(err)
-			}
-		},
+		Run:   cmdutil.DefaultSubCommandRun(errOut),
 	}
 
 	// create subcommands
@@ -54,7 +48,3 @@ func NewCmdTop(f cmdutil.Factory, out io.Writer) *cobra.Command {
 	cmd.AddCommand(NewCmdTopPod(f, out))
 	return cmd
 }
-
-func (o TopOptions) RunTop(f cmdutil.Factory, cmd *cobra.Command, args []string, out io.Writer) error {
-	return cmd.Help()
-}

pkg/kubectl/cmd/top_test.go

@@ -23,13 +23,14 @@ import (
 	"io/ioutil"
 	"time"
 
+	"testing"
+
 	metrics_api "k8s.io/heapster/metrics/apis/metrics/v1alpha1"
 	"k8s.io/kubernetes/pkg/api"
 	"k8s.io/kubernetes/pkg/api/resource"
 	"k8s.io/kubernetes/pkg/api/unversioned"
 	v1 "k8s.io/kubernetes/pkg/api/v1"
 	cmdtesting "k8s.io/kubernetes/pkg/kubectl/cmd/testing"
-	"testing"
 )
 
 const (
@@ -44,7 +45,7 @@ func TestTopSubcommandsExist(t *testing.T) {
 	f, _, _, _ := cmdtesting.NewAPIFactory()
 	buf := bytes.NewBuffer([]byte{})
 
-	cmd := NewCmdTop(f, buf)
+	cmd := NewCmdTop(f, buf, buf)
 	if !cmd.HasSubCommands() {
 		t.Error("top command should have subcommands")
 	}

pkg/kubectl/cmd/util/helpers.go

@@ -752,3 +752,20 @@ func IsSiblingCommandExists(cmd *cobra.Command, targetCmdName string) bool {
 
 	return false
 }
+
+// DefaultSubCommandRun prints a command's help string to the specified output if no
+// arguments (sub-commands) are provided, or a usage error otherwise.
+func DefaultSubCommandRun(out io.Writer) func(c *cobra.Command, args []string) {
+	return func(c *cobra.Command, args []string) {
+		c.SetOutput(out)
+		RequireNoArguments(c, args)
+		c.Help()
+	}
+}
+
+// RequireNoArguments exits with a usage error if extra arguments are provided.
+func RequireNoArguments(c *cobra.Command, args []string) {
+	if len(args) > 0 {
+		CheckErr(UsageError(c, fmt.Sprintf(`unknown command %q`, strings.Join(args, " "))))
+	}
+}