[depot_tools] Find, upload and apply patchset dependencies

rietveld.py

 # coding: utf-8
 # Copyright (c) 2012 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.
 """Defines class Rietveld to easily access a rietveld instance.
 
 Security implications:
 
 The following hypothesis are made:
 - Rietveld enforces:
@@ skipping 66 matching lines @@
 
   def get_issue_properties(self, issue, messages):
     """Returns all the issue's metadata as a dictionary."""
     url = '/api/%d' % issue
     if messages:
       url += '?messages=true'
     data = json.loads(self.get(url, retry_on_404=True))
     data['description'] = '\n'.join(data['description'].strip().splitlines())
     return data
 
+  def get_depends_on_patchset(self, issue, patchset):
+    """Returns the patchset this patchset depends on if it exists."""
+    url = '/%d/patchset/%d/get_depends_on_patchset' % (issue, patchset)
+    resp = None
+    try:
+      resp = json.loads(self.get(url))
+    except (urllib2.HTTPError, ValueError):
+      # The get_depends_on_patchset endpoint does not exist on this Rietveld
+      # instance yet. Ignore the error and proceed.
+      # TODO(rmistry): Make this an error when all Rietveld instances have
+      # this endpoint.
+      pass
+    return resp
+
   def get_patchset_properties(self, issue, patchset):
     """Returns the patchset properties."""
     url = '/api/%d/%d' % (issue, patchset)
     return json.loads(self.get(url))
 
   def get_file_content(self, issue, patchset, item):
     """Returns the content of a new file.
 
     Throws HTTP 302 exception if the file doesn't exist or is not a binary file.
     """
@@ skipping 573 matching lines @@
     ReadOnlyRietveld._local_changes.setdefault(issue, {})['closed'] = True
 
   def get_issue_properties(self, issue, messages):
     data = self._rietveld.get_issue_properties(issue, messages)
     data.update(self._get_local_changes(issue))
     return data
 
   def get_patchset_properties(self, issue, patchset):
     return self._rietveld.get_patchset_properties(issue, patchset)
 
+  def get_depends_on_patchset(self, issue, patchset):
+    return self._rietveld.get_depends_on_patchset(issue, patchset)
+
   def get_patch(self, issue, patchset):
     return self._rietveld.get_patch(issue, patchset)
 
   def update_description(self, issue, description):  # pylint:disable=R0201
     logging.info('ReadOnlyRietveld: new description for issue %d: %s' %
         (issue, description))
 
   def add_comment(self,  # pylint:disable=R0201
                   issue,
                   message,
@@ skipping 10 matching lines @@
       self, issue, patchset, reason, clobber, revision, builders_and_tests,
       master=None, category='cq'):
     logging.info('ReadOnlyRietveld: triggering try jobs %r for issue %d' %
         (builders_and_tests, issue))
 
   def trigger_distributed_try_jobs(  # pylint:disable=R0201
       self, issue, patchset, reason, clobber, revision, masters,
       category='cq'):
     logging.info('ReadOnlyRietveld: triggering try jobs %r for issue %d' %
         (masters, issue))