[Findit] Refactoring trigger swarming task pipelines

appengine/findit/model/wf_swarming_task.py

 # Copyright 2016 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 from collections import defaultdict
 
 from google.appengine.ext import ndb
 
 from model.base_build_model import BaseBuildModel
 from model.base_swarming_task import BaseSwarmingTask
@@ skipping 27 matching lines @@
         # If the test is 'SKIPPED', there should be failure in its dependency,
         # consider it to be failed as well.
         # TODO(chanli): Check more test statuses.
         classified_tests['reliable_tests'].append(test_name)
     return classified_tests
 
   @property
   def reliable_tests(self):
     return self.classified_tests.get('reliable_tests', [])
 
+  @ndb.ComputedProperty
+  def step_name(self):
+    return self.key.pairs()[1][1]
+
   @staticmethod
   def _CreateKey(
       master_name, builder_name, build_number, step_name):  # pragma: no cover
     build_id = BaseBuildModel.CreateBuildId(
         master_name, builder_name, build_number)
     return ndb.Key('WfBuild', build_id, 'WfSwarmingTask', step_name)
 
   @staticmethod
   def Create(
       master_name, builder_name, build_number, step_name):  # pragma: no cover
     task = WfSwarmingTask(
         key=WfSwarmingTask._CreateKey(
             master_name, builder_name, build_number, step_name))
     task.parameters = task.parameters or {}
     task.tests_statuses = task.tests_statuses or {}
     return task
 
   @staticmethod
   def Get(
       master_name, builder_name, build_number, step_name):  # pragma: no cover
     return WfSwarmingTask._CreateKey(
         master_name, builder_name, build_number, step_name).get()