tools/android/loading Prevent gcloud instance leak.

tools/android/loading/cloud/frontend/clovis_frontend.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 logging
 import os
 import sys
 import time
 
 import cloudstorage
@@ skipping 250 matching lines @@
   user_email = email_helper.GetUserEmail()
   user_name = user_email[:user_email.find('@')]
   if user_name:
     task_dir_components.append(user_name)
   task_name = task.BackendParams().get('task_name')
   if task_name:
     task_dir_components.append(task_name)
   task_dir_components.append(task_tag)
   task_dir = os.path.join(task.Action(), '_'.join(task_dir_components))
 
-  # Create the instance template if required.
-  if not CreateInstanceTemplate(task, task_dir):
-    return Render('Template creation failed.', memory_logs)
-
   # Build the URL where the result will live.
   task_url = None
   if task.Action() == 'trace':
     bucket = task.BackendParams().get('storage_bucket')
     if bucket:
       task_url = 'https://console.cloud.google.com/storage/%s/%s' % (bucket,
                                                                      task_dir)
   elif task.Action() == 'report':
     task_url = common.clovis_paths.GetBigQueryTableURL(project_name, task_tag)
   else:
     error_string = 'Unsupported action: %s.' % task.Action()
     clovis_logger.error(error_string)
     return Render(error_string, memory_logs)
   clovis_logger.info('Task result URL: ' + task_url)
 
   # Split the task in smaller tasks.
   sub_tasks = SplitClovisTask(task)
   if not sub_tasks:
     return Render('Task split failed.', memory_logs)
 
   if not EnqueueTasks(sub_tasks, task_tag):
     return Render('Task creation failed.', memory_logs)
 
-  # Start the instances if required.
-  if not CreateInstances(task):
-    return Render('Instance creation failed.', memory_logs)
-
   # Start polling the progress.
   clovis_logger.info('Creating worker polling task.')
   first_poll_delay_minutes = 10
   timeout_hours = task.BackendParams().get('timeout_hours', 5)
   deferred.defer(PollWorkers, task_tag, time.time(), timeout_hours, user_email,
                  task_url, _countdown=(60 * first_poll_delay_minutes))
 
+  # Start the instances if required.
+  if not CreateInstanceTemplate(task, task_dir):
+    return Render('Instance template creation failed.', memory_logs)
+  if not CreateInstances(task):
+    return Render('Instance creation failed.', memory_logs)
+
   return Render(flask.Markup(
       'Success!<br>Your task %s has started.<br>'
       'You will be notified at %s when completed.') % (task_tag, user_email),
       memory_logs)
 
 
 def EnqueueTasks(tasks, task_tag):
   """Enqueues a list of tasks in the Google Cloud task queue, for consumption by
   Google Compute Engine.
   """
@@ skipping 41 matching lines @@
 @app.errorhandler(404)
 def PageNotFound(e):  # pylint: disable=unused-argument
   """Return a custom 404 error."""
   return 'Sorry, Nothing at this URL.', 404
 
 
 @app.errorhandler(500)
 def ApplicationError(e):
   """Return a custom 500 error."""
   return 'Sorry, unexpected error: {}'.format(e), 499