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Dumping RabbitMQ queue contents

Apparently there is no easy way to look at the content of messages in RabbitMQ. the list_queues only will give you a count but if you want to look at all the messages content then there is no easy way. I had few thumbnail generation messages in the queue that the code failed to ACK because of exceptions in code. Now I want to see what files are stuck for thumbnail generation. The best way is to restart the program and Rabbit would redeliver the messages but we cant restart a live system. So the trick is to just write a python program that would consume the message but wont acknowledge it.



import sys
from amqplib import client_0_8 as amqp

def process_message(msg):
     print "================================================="
     print "Properties ="
     print msg.properties
     print "Body=" 
     print msg.body

if __name__ == '__main__':
    if len(sys.argv) < 5:
       print "Usage python list_queue_messages.py mq_url mq_user mq_pass mq_vhost mq_exchange mq_queue_name mq_routing_key"
       exit()
   
    mq_url = sys.argv[1]
    mq_user = sys.argv[2]
    mq_pass = sys.argv[3]
    mq_vhost = sys.argv[4]
    mq_exchange = sys.argv[5]
    mq_queue_name = sys.argv[6]
    mq_routing_key = sys.argv[7]
    conn = amqp.Connection(host=mq_url,
                           userid=mq_user,
                           password=mq_pass,
                           virtual_host=mq_vhost,
                           insist=False);
    chan = conn.channel();
    chan.queue_declare(queue=mq_queue_name, durable=True,
        exclusive=False, auto_delete=False);
    chan.exchange_declare(exchange=mq_exchange, type="direct", durable=True,
        auto_delete=False);        
    chan.queue_bind(queue=mq_queue_name, exchange=mq_exchange,
        routing_key=mq_routing_key)

    print "Consumer consuming messages from %s press CTRL+C when all messages are dumped" % mq_queue_name
    
    chan.basic_consume(queue=mq_queue_name, no_ack=False,
                    callback=process_message)
    try:
        while chan.callbacks:
             chan.wait();
    finally:
        chan.close();
        conn.close();


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