tools/android/loading Add appengine frontend for Clovis

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 flask
+from google.appengine.api import taskqueue
+import json
+import os
+import sys
+import uuid
+
+from common.clovis_task import ClovisTask
+
+
+app = flask.Flask(__name__)
+
+
+def StartFromJson(http_body_str):
+  """Creates a new batch of tasks from its JSON representation."""
+  task = ClovisTask.FromJsonDict(http_body_str)
+  if not task:
+    return 'Invalid JSON task:\n%s\n' % http_body_str
+
+  task_tag = task.TaskqueueTag()
+  if not task_tag:
+    task_tag = uuid.uuid1()
+
+  sub_tasks = []
+  if task.Action() == 'trace':
+    sub_tasks = SplitTraceTask(task)
+  else:
+    return 'Unsupported action: %s\n' % task.Action()
+
+  return EnqueueTasks(sub_tasks, task_tag)
+
+
+def SplitTraceTask(task):
+  """Split a tracing task with potentially many URLs into several tracing tasks
+  with few URLs.
+  """
+  params = task.Params()
+  urls = params['urls']
+
+  # Split the task in smaller tasks with fewer URLs each.
+  urls_per_task = 1
+  sub_tasks = []
+  for i in range(0, len(urls), urls_per_task):
+    sub_task_params = params.copy()
+    sub_task_params['urls'] = [url for url in urls[i:i+urls_per_task]]
+    sub_tasks.append(ClovisTask(task.Action(), sub_task_params,
+                                task.TaskqueueTag()))
+  return sub_tasks
+
+
+def EnqueueTasks(tasks, task_tag):
+  """Enqueues a list of tasks in the Google Cloud task queue, for consumption by
+  Google Compute Engine.
+  """
+  q = taskqueue.Queue('clovis-queue')
+  retry_options = taskqueue.TaskRetryOptions(task_retry_limit=3)
+  # Add tasks to the queue by groups.
+  # TODO(droger): This support to thousands of tasks, but maybe not millions.
+  # Defer the enqueuing if it times out.
+  # is too large.
+  group_size = 100
+  callbacks = []
+  try:
+    for i in range(0, len(tasks), group_size):
+      group = tasks[i:i+group_size]
+      taskqueue_tasks = [
+          taskqueue.Task(payload=task.ToJsonDict(), method='PULL', tag=task_tag,
+                         retry_options=retry_options)
+          for task in group]
+      rpc = taskqueue.create_rpc()
+      q.add_async(task=taskqueue_tasks, rpc=rpc)
+      callbacks.append(rpc)
+    for callback in callbacks:
+      callback.get_result()
+  except Exception as e:
+    return 'Exception:' + type(e).__name__ + ' ' + str(e.args) + '\n'
+  return 'pushed %i tasks with tag: %s\n' % (len(tasks), task_tag)
+
+
+@app.route('/')
+def Root():
+  """Home page: redirect to the static form."""
+  return flask.redirect('/static/form.html')
+
+
+@app.route('/form_sent', methods=['POST'])
+def StartFromForm():
+  """HTML form endpoint"""
+  data_stream = flask.request.files.get('json_task')
+  if not data_stream:
+    return 'failed'
+  http_body_str = data_stream.read()
+  return StartFromJson(http_body_str)
+
+
+@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