Do not retry uploading to blobstore on HTTP 500, regenerate a new url first.

run_isolated.py

 #!/usr/bin/env python
 # 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.
 
 """Reads a .isolated, creates a tree of hardlinks and runs the test.
 
 Keeps a local cache.
 """
 
@@ skipping 518 matching lines @@
         new_url = urlparse.urlunparse(url_parts)
       request = urllib2.Request(new_url, data=payload)
       if payload is not None:
         if content_type:
           request.add_header('Content-Type', content_type)
         request.add_header('Content-Length', len(payload))
       return request
 
     return self._retry_loop(make_request, **kwargs)
 
-  def _retry_loop(self, make_request, retry_404=False):
+  def _retry_loop(self, make_request, retry_404=False, retry_50x=True):
     """Runs internal request-retry loop."""
     authenticated = False
     last_error = None
     for attempt in range(MAX_URL_OPEN_ATTEMPTS):
       extra = {COUNT_KEY: attempt} if attempt else {}
       request = make_request(extra)
       try:
         url_response = self._url_open(request)
         logging.debug('url_open(%s) succeeded', request.get_full_url())
         return url_response
       except urllib2.HTTPError as e:
         # Unauthorized. Ask to authenticate and then try again.
         if e.code in (401, 403):
           # Try to authenticate only once. If it doesn't help, then server does
           # not support app engine authentication.
           logging.error(
               'Authentication is required for %s on attempt %d.\n%s',
               request.get_full_url(), attempt,
               self._format_exception(e, verbose=True))
           if not authenticated and self.authenticate():
             authenticated = True
             continue
           logging.error(
               'Unable to authenticate to %s.\n%s',
               request.get_full_url(), self._format_exception(e, verbose=True))
           return None
 
-        if e.code < 500 and not (retry_404 and e.code == 404):
+        if ((e.code < 500 and not (retry_404 and e.code == 404)) or
+            (e.code >= 500 and not retry_50x)):
           # This HTTPError means we reached the server and there was a problem
           # with the request, so don't retry.
           logging.error(
               'Able to connect to %s but an exception was thrown.\n%s',
               request.get_full_url(), self._format_exception(e, verbose=True))
           return None
 
         # The HTTPError was due to a server error, so retry the attempt.
         logging.warning('Able to connect to %s on attempt %d.\n%s',
                         request.get_full_url(), attempt,
@@ skipping 1196 matching lines @@
     except Exception, e:
       # Make sure any exception is logged.
       logging.exception(e)
       return 1
 
 
 if __name__ == '__main__':
   # Ensure that we are always running with the correct encoding.
   fix_default_encoding()
   sys.exit(main())