add "--force" flag to "kubectl update";

update relevant tests

pkg/kubectl/cmd/update.go

@@ -27,6 +27,7 @@ import (
 	cmdutil "github.com/GoogleCloudPlatform/kubernetes/pkg/kubectl/cmd/util"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/kubectl/resource"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/util"
+	"github.com/golang/glog"
 )
 
 const (
@@ -40,7 +41,10 @@ $ kubectl update -f pod.json
 $ cat pod.json | kubectl update -f -
 
 // Partially update a node using strategic merge patch
-kubectl --api-version=v1 update node k8s-node-1 --patch='{"spec":{"unschedulable":true}}'`
+kubectl --api-version=v1 update node k8s-node-1 --patch='{"spec":{"unschedulable":true}}'
+
+// Force update, delete and then re-create the resource
+kubectl update --force -f pod.json`
 )
 
 func NewCmdUpdate(f *cmdutil.Factory, out io.Writer) *cobra.Command {
@@ -60,6 +64,10 @@ func NewCmdUpdate(f *cmdutil.Factory, out io.Writer) *cobra.Command {
 	cmd.MarkFlagRequired("filename")
 	cmd.Flags().String("patch", "", "A JSON document to override the existing resource. The resource is downloaded, patched with the JSON, then updated.")
 	cmd.MarkFlagRequired("patch")
+	cmd.Flags().Bool("force", false, "Delete and re-create the specified resource")
+	cmd.Flags().Bool("cascade", false, "Only relevant during a force update. If true, cascade the deletion of the resources managed by this resource (e.g. Pods created by a ReplicationController).  Default true.")
+	cmd.Flags().Int("grace-period", -1, "Only relevant during a force update. Period of time in seconds given to the old resource to terminate gracefully. Ignored if negative.")
+	cmd.Flags().Duration("timeout", 0, "Only relevant during a force update. The length of time to wait before giving up on a delete of the old resource, zero means determine a timeout from the size of the object")
 	return cmd
 }
 
@@ -74,6 +82,7 @@ func RunUpdate(f *cmdutil.Factory, out io.Writer, cmd *cobra.Command, args []str
 		return err
 	}
 
+	force := cmdutil.GetFlagBool(cmd, "force")
 	patch := cmdutil.GetFlagString(cmd, "patch")
 	if len(filenames) == 0 && len(patch) == 0 {
 		return cmdutil.UsageError(cmd, "Must specify --filename or --patch to update")
@@ -81,6 +90,9 @@ func RunUpdate(f *cmdutil.Factory, out io.Writer, cmd *cobra.Command, args []str
 	if len(filenames) != 0 && len(patch) != 0 {
 		return cmdutil.UsageError(cmd, "Can not specify both --filename and --patch")
 	}
+	if len(filenames) == 0 && force {
+		return cmdutil.UsageError(cmd, "--force can only be used with --filename")
+	}
 
 	// TODO: Make patching work with -f, updating with patched JSON input files
 	if len(filenames) == 0 {
@@ -95,6 +107,10 @@ func RunUpdate(f *cmdutil.Factory, out io.Writer, cmd *cobra.Command, args []str
 		return cmdutil.UsageError(cmd, "Must specify --filename to update")
 	}
 
+	if force {
+		return forceUpdate(f, out, cmd, args, filenames)
+	}
+
 	mapper, typer := f.Object()
 	r := resource.NewBuilder(mapper, typer, f.ClientMapperForCommand()).
 		Schema(schema).
@@ -160,3 +176,76 @@ func updateWithPatch(cmd *cobra.Command, args []string, f *cmdutil.Factory, patc
 	_, err = helper.Patch(namespace, name, api.StrategicMergePatchType, []byte(patch))
 	return name, err
 }
+
+func forceUpdate(f *cmdutil.Factory, out io.Writer, cmd *cobra.Command, args []string, filenames util.StringList) error {
+	schema, err := f.Validator()
+	if err != nil {
+		return err
+	}
+
+	cmdNamespace, err := f.DefaultNamespace()
+	if err != nil {
+		return err
+	}
+
+	mapper, typer := f.Object()
+	r := resource.NewBuilder(mapper, typer, f.ClientMapperForCommand()).
+		ContinueOnError().
+		NamespaceParam(cmdNamespace).DefaultNamespace().
+		FilenameParam(filenames...).
+		ResourceTypeOrNameArgs(false, args...).RequireObject(false).
+		Flatten().
+		Do()
+	err = r.Err()
+	if err != nil {
+		return err
+	}
+	//Update will create a resource if it doesn't exist already, so ignore not found error
+	ignoreNotFound := true
+	// By default use a reaper to delete all related resources.
+	if cmdutil.GetFlagBool(cmd, "cascade") {
+		glog.Warningf("\"cascade\" is set, kubectl will delete and re-create all resources managed by this resource (e.g. Pods created by a ReplicationController). Consider using \"kubectl rolling-update\" if you want to update a ReplicationController together with its Pods.")
+		err = ReapResult(r, f, out, cmdutil.GetFlagBool(cmd, "cascade"), ignoreNotFound, cmdutil.GetFlagDuration(cmd, "timeout"), cmdutil.GetFlagInt(cmd, "grace-period"))
+	} else {
+		err = DeleteResult(r, out, ignoreNotFound)
+	}
+	if err != nil {
+		return err
+	}
+
+	r = resource.NewBuilder(mapper, typer, f.ClientMapperForCommand()).
+		Schema(schema).
+		ContinueOnError().
+		NamespaceParam(cmdNamespace).RequireNamespace().
+		FilenameParam(filenames...).
+		Flatten().
+		Do()
+	err = r.Err()
+	if err != nil {
+		return err
+	}
+
+	count := 0
+	err = r.Visit(func(info *resource.Info) error {
+		data, err := info.Mapping.Codec.Encode(info.Object)
+		if err != nil {
+			return err
+		}
+		obj, err := resource.NewHelper(info.Client, info.Mapping).Create(info.Namespace, true, data)
+		if err != nil {
+			return err
+		}
+		count++
+		info.Refresh(obj, true)
+		printObjectSpecificMessage(obj, out)
+		fmt.Fprintf(out, "%s/%s\n", info.Mapping.Resource, info.Name)
+		return nil
+	})
+	if err != nil {
+		return err
+	}
+	if count == 0 {
+		return fmt.Errorf("no objects passed to update")
+	}
+	return nil
+}