Monkey patch httplib on python <=2.6.2 to make it work with 'requests' library.

utils/net.py

 # Copyright 2013 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.
 
 """Classes and functions for generic network communication over HTTP."""
 
 import cookielib
 import cStringIO as StringIO
 import httplib
 import itertools
@@ skipping 15 matching lines @@
 from third_party.rietveld import upload
 
 from utils import zip_package
 
 # Hack out upload logging.info()
 upload.logging = logging.getLogger('upload')
 # Mac pylint choke on this line.
 upload.logging.setLevel(logging.WARNING)  # pylint: disable=E1103
 
 
+# TODO(vadimsh): Remove this once we don't have to support python 2.6 anymore.
+def monkey_patch_httplib():
+  """Patch httplib.HTTPConnection to have '_tunnel_host' attribute.
+
+  'requests' library (>= v2) accesses 'HTTPConnection._tunnel_host' attribute
+  added only in python 2.6.3. This function patches HTTPConnection to have it
+  on python 2.6.2 as well.
+  """
+  conn = httplib.HTTPConnection('example.com')
+  if not hasattr(conn, '_tunnel_host'):
+    httplib.HTTPConnection._tunnel_host = None
+monkey_patch_httplib()
+
+
 # Big switch that controls what API to use to make HTTP requests.
 # It's temporary here to simplify benchmarking of old vs new implementation.
 USE_REQUESTS_LIB = True
 
 # The name of the key to store the count of url attempts.
 COUNT_KEY = 'UrlOpenAttempt'
 
 # Default maximum number of attempts to trying opening a url before aborting.
 URL_OPEN_MAX_ATTEMPTS = 30
 
@@ skipping 731 matching lines @@
     attemp_obj = RetryAttempt(attempt, remaining)
     yield attemp_obj
     if attemp_obj.skip_sleep:
       continue
     # Only sleep if we are going to try again.
     if max_attempts and attempt != max_attempts - 1:
       remaining = (timeout - (current_time() - start)) if timeout else None
       if remaining is not None and remaining < 0:
         break
       sleep_before_retry(attempt, remaining)