class SQSProbe(Probe):
def __init__(self, conn_mgr, task_queue, results_topic, state_domain,
state_backend=SDBStateBackend):
self._conn = conn_mgr
self._queue_name = task_queue
self._topic_name = results_topic
self._topic = None
self._queue = None
self._state_backend = state_backend(conn_mgr.sdb, state_domain)
super(SQSProbe, self).__init__()
def _setup_queue(self, **kwargs):
if self._queue:
return
logger.debug("setting up queue %s", self._queue_name)
self._queue = self._conn.sqs.create_queue(self._queue_name)
def _setup_topic(self, **kwargs):
if self._topic:
return
logger.debug("setting up topic %s", self._topic_name)
self._topic = SNSTopic(self._conn, self._topic_name)
def get_task(self, **kwargs):
self._setup_queue(**kwargs)
wait_time = kwargs.get('queue_wait_time')
timeout = kwargs.get('monitor_timeout') + 3
logger.debug("Getting task from queue %s.", self._queue_name)
task_item = self._queue.read(visibility_timeout=timeout,
wait_time_seconds=wait_time)
task = None
if task_item:
task = Task.deserialize(json.loads(task_item.get_body()),
origin=task_item)
return task
def resubmit_task(self, task, delay, **kwargs):
self._setup_queue(**kwargs)
task.increment_attempt()
logger.debug("Resubmitting task %s with %d second delay.", task.id,
delay)
m = Message()
m.set_body(json.dumps(task.serialize()))
return self._queue.write(m, delay_seconds=delay)
def submit_result(self, result, **kwargs):
self._setup_topic()
logger.debug("%s - submitting '%s/%s' result", result.id,
result.state_name, result.state_type_name)
return self._topic.publish(json.dumps(result.serialize()))
