Port ctr to use client

Signed-off-by: Michael Crosby <crosbymichael@gmail.com>

cmd/ctr/ps.go

@@ -5,7 +5,6 @@ import (
 	"os"
 	"text/tabwriter"
 
-	"github.com/containerd/containerd/api/services/execution"
 	"github.com/pkg/errors"
 	"github.com/urfave/cli"
 )
@@ -13,15 +12,9 @@ import (
 var psCommand = cli.Command{
 	Name:  "ps",
 	Usage: "list processes for container",
-	Flags: []cli.Flag{
-		cli.StringFlag{
-			Name:  "id",
-			Usage: "id of the container",
-		},
-	},
 	Action: func(context *cli.Context) error {
 		var (
-			id          = context.String("id")
+			id          = context.Args().First()
 			ctx, cancel = appContext(context)
 		)
 		defer cancel()
@@ -29,34 +22,33 @@ var psCommand = cli.Command{
 		if id == "" {
 			return errors.New("container id must be provided")
 		}
-
-		pr := &execution.ProcessesRequest{
-			ContainerID: id,
+		client, err := newClient(context)
+		if err != nil {
+			return err
 		}
-
-		tasks, err := getTasksService(context)
+		container, err := client.LoadContainer(ctx, id)
 		if err != nil {
 			return err
 		}
 
-		resp, err := tasks.Processes(ctx, pr)
+		task, err := container.Task(ctx, nil)
+		if err != nil {
+			return err
+		}
+		processes, err := task.Processes(ctx)
 		if err != nil {
 			return err
 		}
-
 		w := tabwriter.NewWriter(os.Stdout, 10, 1, 3, ' ', 0)
 		fmt.Fprintln(w, "PID")
-		for _, ps := range resp.Processes {
-			if _, err := fmt.Fprintf(w, "%d\n",
-				ps.Pid,
-			); err != nil {
+		for _, ps := range processes {
+			if _, err := fmt.Fprintf(w, "%d\n", ps); err != nil {
 				return err
 			}
 		}
 		if err := w.Flush(); err != nil {
 			return err
 		}
-
 		return nil
 	},
 }