Add retries to pfq push.

cros_mark_as_stable.py

 #!/usr/bin/python
 
 # Copyright (c) 2010 The Chromium OS Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """This module uprevs a given package's ebuild to the next revision."""
 
 
 import fileinput
@@ skipping 197 matching lines @@
 
 def _PushChange():
   """Pushes changes to the git repository.
 
   Pushes locals commits from calls to CommitChange to the remote git
   repository specified by os.pwd.
 
   Raises:
       OSError: Error occurred while pushing.
   """
+  num_retries = 5
 
   # TODO(sosa) - Add logic for buildbot to check whether other slaves have
   # completed and push this change only if they have.
 
   # Sanity check to make sure we're on a stabilizing branch before pushing.
   if not _CheckOnStabilizingBranch():
     Info('Not on branch %s so no work found to push.  Exiting' % \
         _STABLE_BRANCH_NAME)
     return
 
   description = _SimpleRunCommand('git log --format=format:%s%n%n%b ' +
                             gflags.FLAGS.tracking_branch + '..')
   description = 'Marking set of ebuilds as stable\n\n%s' % description
   merge_branch_name = 'merge_branch'
-  _SimpleRunCommand('git remote update')
-  merge_branch = _GitBranch(merge_branch_name)
-  merge_branch.CreateBranch()
-  if not merge_branch.Exists():
-    Die('Unable to create merge branch.')
-  _SimpleRunCommand('git merge --squash %s' % _STABLE_BRANCH_NAME)
-  _SimpleRunCommand('git commit -m "%s"' % description)
-  # Ugh. There has got to be an easier way to push to a tracking branch
-  _SimpleRunCommand('git config push.default tracking')
-  _SimpleRunCommand('git push')
+  for push_try in range(num_retries + 1):
+    try:
+      _SimpleRunCommand('git remote update')
+      merge_branch = _GitBranch(merge_branch_name)
+      merge_branch.CreateBranch()
+      if not merge_branch.Exists():
+        Die('Unable to create merge branch.')
+      _SimpleRunCommand('git merge --squash %s' % _STABLE_BRANCH_NAME)
+      _SimpleRunCommand('git commit -m "%s"' % description)
+      # Ugh. There has got to be an easier way to push to a tracking branch
+      _SimpleRunCommand('git config push.default tracking')
+      _SimpleRunCommand('git push')
+      break
+    except:
+      if push_try < num_retries:
+        Warning('Failed to push change, performing retry (%s/%s)' % (
+            push_try + 1, num_retries))
+      else:
+        raise
 
 
 def _SimpleRunCommand(command):
   """Runs a shell command and returns stdout back to caller."""
   _Print('  + %s' % command)
   proc_handle = subprocess.Popen(command, stdout=subprocess.PIPE, shell=True)
   stdout = proc_handle.communicate()[0]
   retcode = proc_handle.wait()
   if retcode != 0:
     _Print(stdout)
@@ skipping 297 matching lines @@
           raise
 
       if revved_packages:
         _CleanStalePackages(gflags.FLAGS.board, revved_packages)
       else:
         work_branch.Delete()
 
 
 if __name__ == '__main__':
   main(sys.argv)