BuildBucket-based build triggering

scripts/master/buildbucket/client.py

 # Copyright 2015 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.
 
 """This file contains buildbucket service client."""
 
 import json
 import logging
 import sys
 
 from master import auth
 from master.buildbucket import common
 from master.deferred_resource import DeferredResource
 
 from oauth2client.client import SignedJwtAssertionCredentials
 import httplib2
 import apiclient
 
 
 BUILDBUCKET_HOSTNAME_PRODUCTION = 'cr-buildbucket.appspot.com'
 BUILDBUCKET_HOSTNAME_TESTING = 'cr-buildbucket-test.appspot.com'
 
 
 def buildbucket_api_discovery_url(hostname=None):
   return (
       'https://%s/_ah/api/discovery/v1/apis/{api}/{apiVersion}/rest' % hostname)
 
+
+def get_default_buildbucket_hostname(master):
+  return (
+      BUILDBUCKET_HOSTNAME_PRODUCTION if master.is_production_host
+      else BUILDBUCKET_HOSTNAME_TESTING)
+
+
 def create_buildbucket_service(
     master, hostname=None, verbose=None):
   """Asynchronously creates buildbucket API resource.
 
   Returns:
     A DeferredResource as Deferred.
   """
-  hostname = hostname or (
-      BUILDBUCKET_HOSTNAME_PRODUCTION if master.is_production_host
-      else BUILDBUCKET_HOSTNAME_TESTING)
+  hostname = hostname or get_default_buildbucket_hostname(master)
   return DeferredResource.build(
       'buildbucket',
       'v1',
       http_factory=lambda: auth.create_http(master),
       discoveryServiceUrl=buildbucket_api_discovery_url(hostname),
       verbose=verbose or False,
       log_prefix=common.LOG_PREFIX,
   )