[Findit] Bailing out if build data is too old and moving relevant settings to config

appengine/findit/waterfall/build_util.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.
 
 from datetime import datetime
 
 from common.http_client_appengine import HttpClientAppengine as HttpClient
 from model.wf_build import WfBuild
 from waterfall import buildbot
 from waterfall import lock_util
+from waterfall import waterfall_config
 
 
 HTTP_CLIENT_LOGGING_ERRORS = HttpClient()
 HTTP_CLIENT_NO_404_ERROR = HttpClient(no_error_logging_statuses=[404])
+CHROME_BUILD_EXTRACT = 'CBE'
+BUILDBOT_MASTER = 'BM'
 
 
 def _BuildDataNeedUpdating(build):
-  return (not build.data or (not build.completed and
-      (datetime.utcnow() - build.last_crawled_time).total_seconds() >= 300))
+  return (not build.data or (
+      not build.completed and (
+          datetime.utcnow() - build.last_crawled_time).total_seconds() >= 300))
 
 
 def DownloadBuildData(master_name, builder_name, build_number):
   """Downloads build data and returns a WfBuild instance."""
   build = WfBuild.Get(master_name, builder_name, build_number)
   if not build:
     build = WfBuild.Create(master_name, builder_name, build_number)
 
   # Cache the data to avoid pulling from master again.
   if _BuildDataNeedUpdating(build):
-    # Retrieve build data from build archive first.
-    build.data = buildbot.GetBuildDataFromArchive(
-        master_name, builder_name, build_number, HTTP_CLIENT_NO_404_ERROR)
+    use_cbe = waterfall_config.GetDownloadBuildDataSettings().get(
+        'use_chrome_build_extract')
 
-    if build.data is None:
-      if not lock_util.WaitUntilDownloadAllowed(
+    if use_cbe:
+      # Retrieve build data from build archive first.
+      build.data = buildbot.GetBuildDataFromArchive(
+          master_name, builder_name, build_number, HTTP_CLIENT_NO_404_ERROR)
+
+      if build.data:
+        build.data_source = CHROME_BUILD_EXTRACT
+      elif not lock_util.WaitUntilDownloadAllowed(
           master_name):  # pragma: no cover
         return None
 
+    if not build.data:
       # Retrieve build data from build master.
       build.data = buildbot.GetBuildDataFromBuildMaster(
           master_name, builder_name, build_number, HTTP_CLIENT_LOGGING_ERRORS)
+      build.data_source = BUILDBOT_MASTER
 
     build.last_crawled_time = datetime.utcnow()
     build.put()
 
   return build