[Findit] Use PubSub built-in authentication for push endpoint.

appengine/findit/handlers/crash/fracas_crash.py

Index: appengine/findit/handlers/crash/fracas_crash.py
diff --git a/appengine/findit/handlers/crash/fracas_crash.py b/appengine/findit/handlers/crash/fracas_crash.py
index 5112bfcc940670a40cb8e4608a9641c1a2fc51d0..d4d9f777f92fa73c4e3ce7b44bc61da3a4c85633 100644
--- a/appengine/findit/handlers/crash/fracas_crash.py
+++ b/appengine/findit/handlers/crash/fracas_crash.py
@@ -10,14 +10,10 @@ from common import constants
 from common.base_handler import BaseHandler
 from common.base_handler import Permission
 from crash import fracas_crash_pipeline
-from model.crash.crash_config import CrashConfig
-
-
-FRACAS_ANALYSIS_QUEUE = 'fracas-crash-queue'
 
 
 class FracasCrash(BaseHandler):
-  PERMISSION_LEVEL = Permission.ANYONE
+  PERMISSION_LEVEL = Permission.ADMIN
 
   def HandlePost(self):
     """Handles push delivery from Pub/Sub for crash data.
@@ -35,13 +31,6 @@ class FracasCrash(BaseHandler):
       },
     }
     """
-    token = self.request.get('token', '').strip()
-    crash_config = CrashConfig.Get()
-    if token != crash_config.fracas.get('crash_data_push_token'):
-      logging.warning('Unauthorized access.')
-      return self.CreateError(
-          'Unauthorized access: invalid token "%s"' % token, 403)
-
     received_message = json.loads(self.request.body)
     pubsub_message = received_message['message']
     crash_data = json.loads(base64.b64decode(pubsub_message['data']))
@@ -49,8 +38,12 @@ class FracasCrash(BaseHandler):
     logging.info('Processing message %s from subscription %s.',
                  pubsub_message['message_id'], received_message['subscription'])
 
-    fracas_crash_pipeline.ScheduleNewAnalysisForCrash(
-        crash_data['channel'], crash_data['platform'], crash_data['signature'],
-        crash_data['stack_trace'], crash_data['chrome_version'],
-        crash_data['versions_to_cpm'],
-        queue_name=constants.CRASH_ANALYSIS_FRACAS_QUEUE)
+    try:
+      fracas_crash_pipeline.ScheduleNewAnalysisForCrash(
+          crash_data['channel'], crash_data['platform'],
+          crash_data['signature'], crash_data['stack_trace'],
+          crash_data['chrome_version'], crash_data['versions_to_cpm'],
+          queue_name=constants.CRASH_ANALYSIS_FRACAS_QUEUE)
+    except KeyError:  # pragma: no cover.
+      # TODO: save exception in datastore and create a page to show them.
+      logging.exception('Failed to process fracas message')