@Test
  public void testDeriveImage() throws Throwable {
    ImageCreateSpec imageCreateSpec = new ImageCreateSpec();
    imageCreateSpec.setName("i1");
    imageCreateSpec.setReplicationType(ImageReplicationType.EAGER);

    ImageEntity vmImage =
        entityFactory.createImage(
            "image1", ImageState.READY, ImageReplicationType.EAGER, 100L, "n1", "v1", "n2", "v2");

    flushSession();

    String imageId = imageBackend.deriveImage(imageCreateSpec, vmImage).getId();

    flushSession();

    ImageEntity image = imageBackend.findById(imageId);
    assertThat(image.getName(), is(imageCreateSpec.getName()));
    assertThat(image.getReplicationType(), is(imageCreateSpec.getReplicationType()));
    assertThat(image.getState(), is(ImageState.CREATING));
    assertThat(image.getSize(), is(100L));
    assertThat(
        image.getImageSettingsMap(),
        is((Map<String, String>) ImmutableMap.of("n1", "v1", "n2", "v2")));
  }
  @Test
  public void testTombstone() throws Throwable {
    TaskEntity task =
        imageBackend.prepareImageUpload(inputStream, "image-name", ImageReplicationType.ON_DEMAND);
    StepEntity step = task.getSteps().get(0);
    ImageEntity image = (ImageEntity) step.getTransientResourceEntities().get(0);
    assertThat(image.getState(), is(ImageState.CREATING));

    image.setState(ImageState.READY);
    flushSession();

    TenantEntity tenant = new TenantEntity();
    tenant.setName("t1");
    tenantDao.create(tenant);

    ProjectEntity project = new ProjectEntity();
    project.setTenantId(tenant.getId());
    project.setName("staging");
    projectDao.create(project);

    VmEntity vm = new VmEntity();
    vm.setName("vm-1");
    vm.setProjectId(project.getId());
    vm.setImageId(image.getId());
    vmDao.create(vm);

    flushSession();

    imageBackend.tombstone(image);
    assertThat(image.getState(), is(ImageState.PENDING_DELETE));

    vm = vmDao.findById(vm.getId()).get();
    vmDao.delete(vm);
    flushSession();

    imageBackend.tombstone(image);
    try {
      imageBackend.findById(image.getId());
      fail("Image should be deleted in database");
    } catch (ImageNotFoundException e) {
    }
  }