@JsonIgnore
  public Map<String, StepTransition> getDag() {
    return steps.stream().collect(MapHelper.toListMap(Step::getId, Step::getTransition));
  }
@Test
  public void testGetDag() throws Exception {
    Workflow wf =
        loadObject(
                "fixtures/workflows/definition/sample-active-wf-with-props.json",
                WorkflowDefinition.class)
            .getWorkflow();
    assertEquals(
        threeItemMap(
            "job.1", wf.getSteps().get(0).getTransition(),
            "job.2", wf.getSteps().get(1).getTransition(),
            "job.3", wf.getSteps().get(2).getTransition()),
        wf.getDag());
  }