[Findit] Integrate with Fracas through Pub/Sub.

appengine/findit/handlers/crash/fracas_crash.py

+# Copyright 2016 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.
+
+import base64
+import json
+import logging
+
+from base_handler import BaseHandler
+from base_handler import Permission
+from common import constants
+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
+
+  def HandlePost(self):
+    """Handles push delivery from Pub/Sub for crash data."""
+    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']))
+
+    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'],

[mimee, 2016/04/07 23:43:09]

I prefer passing the object and unpacking it in the implementation. Or specify
that you only take a particular json form. Also, we use just 'version', not
'chrome_version'. I think Chrome is implied.

[stgao, 2016/04/08 01:14:08]

I'd unpack the json here to prevent malformed data from propagating  all the way
to the backend.

Updated the documentation here.
I'd make it explicit, because dependencies (like v8, pdfium, etc) also have
version or revisions.
We might need an clankium_version later for Chrome on Android.

+        crash_data['stack_trace'], crash_data['chrome_version'],
+        crash_data['cpm'], queue_name=constants.CRASH_ANALYSIS_FRACAS_QUEUE)