def list_subscriptions(topic,
                       max_results,
                       app_id=None,
                       sub_id_start=None,
                       expires_before=None):

  request = prospective_search_pb.ListSubscriptionsRequest()
  if app_id:
    request.set_app_id(app_id)
  request.set_topic(topic)
  request.set_subscription_id_start(sub_id_start)
  request.set_max_results(max_results)
  if expires_before:
    request.set_expires_before(expires_before)
  response = prospective_search_pb.ListSubscriptionsResponse()
  apiproxy_stub_map.MakeSyncCall('matcher', 'ListSubscriptions',
                                 request, response)
  subscriptions = []
  for sub in response.subscription_list():
    subscriptions.append((sub.id(),
                          sub.vanilla_query(),
                          sub.expiration_time_sec(),
                          sub.state(),
                          sub.error_message()))
  return subscriptions
List subscriptions on a topic.
dataset/ETHPy150Open AppScale/appscale/AppServer/google/appengine/api/prospective_search/prospective_search_admin.py/list_subscriptions