ctr: move tasks, run to commands package

Signed-off-by: Jess Valarezo <valarezo.jessica@gmail.com>

cmd/ctr/commands/tasks/ps.go

@@ -0,0 +1,59 @@
+package tasks
+
+import (
+	"fmt"
+	"os"
+	"text/tabwriter"
+
+	"github.com/containerd/containerd/cmd/ctr/commands"
+	"github.com/containerd/containerd/windows/hcsshimtypes"
+	"github.com/pkg/errors"
+	"github.com/urfave/cli"
+)
+
+var psCommand = cli.Command{
+	Name:      "ps",
+	Usage:     "list processes for container",
+	ArgsUsage: "CONTAINER",
+	Action: func(context *cli.Context) error {
+		id := context.Args().First()
+		if id == "" {
+			return errors.New("container id must be provided")
+		}
+		client, ctx, cancel, err := commands.NewClient(context)
+		if err != nil {
+			return err
+		}
+		defer cancel()
+		container, err := client.LoadContainer(ctx, id)
+		if err != nil {
+			return err
+		}
+
+		task, err := container.Task(ctx, nil)
+		if err != nil {
+			return err
+		}
+		processes, err := task.Pids(ctx)
+		if err != nil {
+			return err
+		}
+		w := tabwriter.NewWriter(os.Stdout, 10, 1, 3, ' ', 0)
+		fmt.Fprintln(w, "PID\tINFO")
+		for _, ps := range processes {
+			if ps.Info != nil {
+				var details hcsshimtypes.ProcessDetails
+				if err := details.Unmarshal(ps.Info.Value); err == nil {
+					if _, err := fmt.Fprintf(w, "%d\t%+v\n", ps.Pid, details); err != nil {
+						return err
+					}
+				}
+			} else {
+				if _, err := fmt.Fprintf(w, "%d\t-\n", ps.Pid); err != nil {
+					return err
+				}
+			}
+		}
+		return w.Flush()
+	},
+}