implement checkpoint in containerd shim

pkg/shim/v1/runsc/service.go

@@ -609,7 +609,23 @@ func (s *runscService) CloseIO(ctx context.Context, r *taskAPI.CloseIORequest) (
 
 // Checkpoint checkpoints the container.
 func (s *runscService) Checkpoint(ctx context.Context, r *taskAPI.CheckpointTaskRequest) (*types.Empty, error) {
-	return empty, errdefs.ErrNotImplemented
+	if s.task == nil {
+		log.L.Debugf("Checkpoint error, id: %s: container not created", r.ID)
+		return nil, errdefs.ToGRPCf(errdefs.ErrFailedPrecondition, "container must be created")
+	}
+
+	opts := &runsccmd.CheckpointOpts{
+		ImagePath: r.Path,
+	}
+
+	err := s.task.Runtime().Checkpoint(ctx, r.ID, opts)
+	if err != nil {
+		log.L.Debugf("Checkpoint failed: %v", err)
+
+		return nil, err
+	}
+	log.L.Debugf("Checkpoint succeeded")
+	return empty, nil
 }
 
 // Restore restores the container.

pkg/shim/v1/runsccmd/runsc.go

@@ -264,6 +264,32 @@ func (r *Runsc) Restore(context context.Context, id string, cio runc.IO, opts *R
 	return r.start(context, cio, r.command(context, append(args, id)...))
 }
 
+// CheckpointOpts is a set of options to runsc.Checkpoint().
+type CheckpointOpts struct {
+	ImagePath    string
+	LeaveRunning bool
+}
+
+func (o *CheckpointOpts) args() []string {
+	var out []string
+	if o.ImagePath != "" {
+		out = append(out, fmt.Sprintf("--image-path=%s", o.ImagePath))
+	}
+	if o.LeaveRunning {
+		out = append(out, "--leave-running")
+	}
+	return out
+}
+
+// Checkpoint checkpoints the container.
+func (r *Runsc) Checkpoint(context context.Context, id string, opts *CheckpointOpts) error {
+	args := []string{"checkpoint"}
+	if opts != nil {
+		args = append(args, opts.args()...)
+	}
+	return r.runOrError(r.command(context, append(args, id)...))
+}
+
 type waitResult struct {
 	ID         string `json:"id"`
 	ExitStatus int    `json:"exitStatus"`