AWS ActiveMQ fetch messages from a Consumer and send to a queue

Question

I am trying to fetch messages from a consumer and send it to a queue. For this I am using Stomp.py After going through articles and posts, I wrote below code:

import ssl
import stomp

stompurl = "xxxxxxxx.mq.us-west-2.amazonaws.com"
stompuser = "stomuser"
stomppass = "password"


class MyListener(stomp.ConnectionListener):
    msg_list = []

    def __init__(self):
        self.msg_list = []

    def on_error(self, frame):
        self.msg_list.append('(ERROR) ' + frame.body)

    def on_message(self, frame):
        self.msg_list.append(frame.body)


conn = stomp.Connection(host_and_ports=[(stompurl, "61614")], auto_decode=True)
conn.set_ssl(for_hosts=[(stompurl, "61614")], ssl_version=ssl.PROTOCOL_TLS)
lst = MyListener()
listener = conn.set_listener('', lst)
conn.connect(stompuser, stomppass, wait=True)
# conn.send(body='Test message', destination='Test_QUEUE')
conn.subscribe('Test_QUEUE', '102')
print(listener.message_list)
import time; time.sleep(2)
messages = lst.msg_list
# conn.disconnect()
print(messages)

With this code I am able to send messages to Test_QUEUE but I can't fetch all messages from consumer. How can I pull out all messages from a consumer and post to a queue for processing.

Answer 1

I'm not a Python + STOMP expert, but in every other language I've used when you create an asynchronous (i.e. non-blocking) message listener as you have done then you must prevent your application from exiting. You have a time.sleep(2) in there, but is that realistically enough time to fetch all the messages from the queue?

It appears your application will exit after print(messages) which means that if you don't get all the messages during the time.sleep(2) then your application will simply terminate.