Add a separate CLI for cri-containerd ctrcri.

Signed-off-by: Lantao Liu <lantaol@google.com>

cmd/cri-containerd/cri_containerd.go

@@ -82,7 +82,6 @@ func main() {
 	o.AddFlags(cmd.Flags())
 	cmd.AddCommand(defaultConfigCommand())
 	cmd.AddCommand(versionCommand())
-	cmd.AddCommand(loadImageCommand())
 
 	cmd.RunE = func(cmd *cobra.Command, args []string) error {
 		setupDumpStacksTrap()

cmd/cri-containerd/options/options.go

@@ -19,7 +19,6 @@ package options
 import (
 	"fmt"
 	"os"
-	"time"
 
 	"github.com/BurntSushi/toml"
 	"github.com/containerd/containerd"
@@ -31,8 +30,6 @@ const (
 	configFilePathArgName = "config"
 	// defaultConfigFilePath is the default config file path.
 	defaultConfigFilePath = "/etc/cri-containerd/config.toml"
-	// connectionTimeout is the grpc connection timeout.
-	connectionTimeout = 10 * time.Second
 )
 
 // ContainerdConfig contains toml config related to containerd
@@ -234,13 +231,6 @@ func PrintDefaultTomlConfig() {
 	}
 }
 
-// AddGRPCFlags add flags for grpc connection.
-func AddGRPCFlags(fs *pflag.FlagSet) (*string, *time.Duration) {
-	endpoint := fs.String("endpoint", DefaultConfig().SocketPath, "cri-containerd endpoint.")
-	timeout := fs.Duration("timeout", connectionTimeout, "cri-containerd connection timeout.")
-	return endpoint, timeout
-}
-
 // DefaultConfig returns default configurations of cri-containerd.
 func DefaultConfig() Config {
 	return Config{

cmd/ctrcri/ctrcri.go

@@ -0,0 +1,84 @@
+/*
+Copyright 2018 The Containerd 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 main
+
+import (
+	"os"
+	"time"
+
+	"github.com/spf13/cobra"
+	"github.com/spf13/pflag"
+
+	"github.com/containerd/cri-containerd/cmd/cri-containerd/options"
+	"github.com/containerd/cri-containerd/pkg/version"
+)
+
+const (
+	// Add \u200B to avoid the space trimming.
+	desc = "\u200B" + `        __                 _ 
+  _____/ /________________(_)
+ / ___/ __/ ___/ ___/ ___/ / 
+/ /__/ /_/ /  / /__/ /  / /  
+\___/\__/_/   \___/_/  /_/   
+
+containerd CRI plugin CLI
+`
+	command = "ctrcri"
+)
+
+var cmd = &cobra.Command{
+	Use:   command,
+	Short: "A CLI for containerd CRI plugin.",
+	Long:  desc,
+}
+
+var (
+	// address is the address for containerd's GRPC server.
+	address string
+	// timeout is the timeout for containerd grpc connection.
+	timeout time.Duration
+	// defaultTimeout is the default timeout for containerd grpc connection.
+	defaultTimeout = 10 * time.Second
+)
+
+func addGlobalFlags(fs *pflag.FlagSet) {
+	// TODO(random-liu): Change default to containerd/defaults.DefaultAddress after cri plugin
+	// become default.
+	fs.StringVar(&address, "address", options.DefaultConfig().SocketPath, "address for containerd's GRPC server.")
+	fs.DurationVar(&timeout, "timeout", defaultTimeout, "timeout for containerd grpc connection.")
+}
+
+func versionCommand() *cobra.Command {
+	return &cobra.Command{
+		Use:   "version",
+		Short: "Print " + command + " version information.",
+		Run: func(cmd *cobra.Command, args []string) {
+			version.PrintVersion()
+		},
+	}
+}
+
+func main() {
+	addGlobalFlags(cmd.PersistentFlags())
+
+	cmd.AddCommand(versionCommand())
+	cmd.AddCommand(loadImageCommand())
+	if err := cmd.Execute(); err != nil {
+		// Error should have been reported.
+		os.Exit(1)
+	}
+}

cmd/ctrcri/load.go

@@ -25,7 +25,6 @@ import (
 	"github.com/spf13/cobra"
 	"golang.org/x/net/context"
 
-	"github.com/containerd/cri-containerd/cmd/cri-containerd/options"
 	api "github.com/containerd/cri-containerd/pkg/api/v1"
 	"github.com/containerd/cri-containerd/pkg/client"
 )
@@ -41,21 +40,20 @@ var (
 		TAR - The path to a tar archive containing a container image.
 
 		Requirement:
-			Containerd and cri-containerd daemons (grpc servers) must already be up and
-			running before the load command is used.
+			Containerd and its cri plugin must already be up and running before the load
+			command is used.
 
 		Description:
-			Running as a client, cri-containerd implements the load command by sending the
-			load request to the already running cri-containerd daemon/server, which in
-			turn loads the image into containerd's image storage via the already running
-			containerd daemon.`)
+			Running as a client, ` + command + ` implements the load command by sending the
+			load request to the already running containerd daemon/server, which in
+			turn loads the image into containerd's image storage.`)
 
 	loadExample = dedent(`
 		- use docker to pull the latest busybox image and save it as a tar archive:
 			$ docker pull busybox:latest
 			$ docker save busybox:latest -o busybox.tar
-		- use cri-containerd to load the image into containerd's image storage:
-			$ cri-containerd load busybox.tar`)
+		- use ` + command + ` to load the image into containerd's image storage:
+			$ ` + command + ` load busybox.tar`)
 )
 
 func loadImageCommand() *cobra.Command {
@@ -67,9 +65,8 @@ func loadImageCommand() *cobra.Command {
 		Example: loadExample,
 	}
 	c.SetUsageTemplate(strings.Replace(c.UsageTemplate(), "Examples:", "Example:", 1))
-	endpoint, timeout := options.AddGRPCFlags(c.Flags())
 	c.RunE = func(cmd *cobra.Command, args []string) error {
-		cl, err := client.NewCRIContainerdClient(*endpoint, *timeout)
+		cl, err := client.NewCRIContainerdClient(address, timeout)
 		if err != nil {
 			return fmt.Errorf("failed to create grpc client: %v", err)
 		}