def deadlettering_exchange(self, rabbit_config, exchange, queue):
conn = Connection(rabbit_config[AMQP_URI_CONFIG_KEY])
with connections[conn].acquire(block=True) as connection:
deadletter_exchange = Exchange(name="deadletter", type="topic")
deadletter_exchange.maybe_bind(connection)
deadletter_exchange.declare()
deadletter_queue = Queue(
name="deadletter",
exchange=deadletter_exchange,
routing_key="#",
queue_arguments={'x-dead-letter-exchange': exchange.name})
deadletter_queue.maybe_bind(connection)
deadletter_queue.declare()
return deadletter_exchange
class Listener():
""" Simple class to wrap the operations needed for an AMQP listener """
def __init__(self, hostname="127.0.0.1", userid="guest", password="******",
virtual_host="/", port=5672):
""" Setup a connection to the AMQP server, get a channel
Create a topic exchange, attach a bonded queue to it
and register a consumer callback.
A specific service listener implementation overrides the name
and routing_key
"""
self.connection = BrokerConnection(hostname=hostname,
userid=userid, password=password,
virtual_host=virtual_host, port=port,
insist=False, ssl=False)
self.channel = self.connection.channel()
self.exchange = Exchange(name=self.name, type="topic", durable=True,
channel=self.channel)
self.queue = Queue(self.name, exchange=self.exchange,
routing_key=self.routing_key)
self.queue = self.queue(self.channel)
self.queue.declare()
self.queue.consume(consumer_tag="", callback=self.callback, no_ack=True)
self.connection.connect()
return
def callback(self, msg):
""" This callback is run when a message is recieved """
return
def consume(self):
""" Event loop """
while True:
self.connection.drain_events()
return
