Example #1
0
File: export.go Project: nhlfr/rkt
// mountOverlay mounts the app from the overlay-rendered pod to the destination directory.
func mountOverlay(pod *pkgPod.Pod, app *schema.RuntimeApp, dest string) error {
	if _, err := os.Stat(dest); err != nil {
		return err
	}

	s, err := imagestore.NewStore(getDataDir())
	if err != nil {
		return errwrap.Wrap(errors.New("cannot open store"), err)
	}

	ts, err := treestore.NewStore(treeStoreDir(), s)
	if err != nil {
		return errwrap.Wrap(errors.New("cannot open treestore"), err)
	}

	treeStoreID, err := pod.GetAppTreeStoreID(app.Name)
	if err != nil {
		return err
	}
	lower := ts.GetRootFS(treeStoreID)
	imgDir := filepath.Join(filepath.Join(pod.Path(), "overlay"), treeStoreID)
	if _, err := os.Stat(imgDir); err != nil {
		return err
	}
	upper := filepath.Join(imgDir, "upper", app.Name.String())
	if _, err := os.Stat(upper); err != nil {
		return err
	}
	work := filepath.Join(imgDir, "work", app.Name.String())
	if _, err := os.Stat(work); err != nil {
		return err
	}

	if err := overlay.Mount(&overlay.MountCfg{lower, upper, work, dest, ""}); err != nil {
		return errwrap.Wrap(errors.New("problem mounting overlayfs directory"), err)
	}

	return nil
}