re-queue all messages from one queue to another with pika

Question

I need to loop though all the messages in the queue for the callback and then close the call back. I need it to stop consuming once the queue is empty. So I'm writing the messages from one queue to another queue.

creds = pika.PlainCredentials(app.config['mq.user'], app.config['mq.pass']) connection = pika.BlockingConnection(pika.ConnectionParameters( host=app.config['mq.host'], credentials=creds)) connection2 = pika.BlockingConnection(pika.ConnectionParameters( host=app.config['mq.host'], credentials=creds))

    channel = connection.channel()
    channel2 = connection2.channel()

Def requeue_callback(ch, method, properties, body):
try:
    msg = json.loads(body)
    ch2.basic_publish(exchange='',
                      routing_key=base_queue+'.request',
                      body = msg['orig_msg'])
finally:
    ch.basic_ack(delivery_tag = method.delivery_tag)

channel.basic_consume(requeue_callback,
                  queue=base_queue+'.error')

channel.start_consuming()

*Alternatively I could find the number of messages in a queue and then consume that specific number. In that case how would I re-queue a specific number.

Answer 1

In your callback function you can to declare queue with passive=True, then use result to get message count.

For example:

>>> ch = rabbit.connection.channel()
>>> method = ch.queue_declare('sandbox', passive=True)
>>> method.method.message_count
23
>>> 

Then check if this number is 0.