Error “unknown delivery tag” occurs when i try ack messages to RabbitMQ using pika (python)

Question

I want process messages in few threads but i\'m getting error during execute this code:

from __future__ import with_statement
import pika
import sys
from pika.ad         


        

Answer 1

For me, it was just that I told the queue I wasn't going to ack, then I acked.

E.g. WRONG:

channel.basic_consume(callback, queue=queue_name, no_ack=True)

and then in my callback:

def callback(ch, method, properties, body):
  # do stuff
  ch.basic_ack(delivery_tag = method.delivery_tag)

RIGHT:

channel.basic_consume(callback, queue=queue_name, no_ack=False)

Bottom line: If you want to manually ack, set no_ack=False.

From the docs:

no_ack: (bool) if set to True, automatic acknowledgement mode will be used (see http://www.rabbitmq.com/confirms.html)