Source code for domain_event_broker.replay

from .transport import Transport
from . import settings


RETRY = 'retry'
LEAVE = 'leave'
DISCARD = 'discard'


def retry_event(**kwargs):
    return RETRY


[docs]def replay_event(queue_name, message_callback=retry_event, connection_settings=settings.DEFAULT): """ Move one domain event from a dead-letter queue back into the processing queue. :param str queue_name: Name of the queue where to move the event. :param function message_callback: A callable that receives the event and returns either ``RETRY``, ``LEAVE`` or ``DISCARD``. :param str connection_settings: :return: The number of messages left in the dead letter queue. :rtype: int """ if connection_settings is None: return 0 elif connection_settings is settings.DEFAULT: connection_settings = settings.BROKER retry_exchange = queue_name + '-retry' dead_letter_queue = queue_name + '-dl' transport = Transport(connection_settings) transport.connect() frame, header, body = transport.channel.basic_get(dead_letter_queue) if frame is None: return 0 action = message_callback(frame=frame, header=header, body=body) if action == RETRY: transport.channel.basic_publish(exchange=retry_exchange, routing_key=frame.routing_key, body=body, ) transport.channel.basic_ack(frame.delivery_tag) elif action == DISCARD: transport.channel.basic_ack(frame.delivery_tag) elif action == LEAVE: transport.channel.basic_reject(frame.delivery_tag, requeue=True) else: transport.channel.basic_reject(frame.delivery_tag, requeue=True) raise Exception("Invalid action '{}'".format(action)) return frame.message_count
[docs]def replay_all(queue_name, message_callback=retry_event, connection_settings=settings.DEFAULT): """ Replay all messages currently in the dead-letter queue. Return number of messages dead-lettered since starting the replay. """ remainder = replay_event(queue_name, message_callback, connection_settings=connection_settings) for _ in range(remainder): remainder = replay_event(queue_name, message_callback, connection_settings=connection_settings) return remainder