My web app needs to be able to send XMPP messages (Facebook Chat), and I thought Celery might be a good solution for this. A task would consist of querying the database and sending the XMPP message to a number of users. However, with that approach I would have to connect to the XMPP server every time I run a task, which is not a great idea.

From the Facebook Chat API docs:

Best Practices

• Your Facebook Chat integration should only be used for sessions that are expected to be long-lived. Clients should not rapidly churn on and off.

Is there a way to share an XMPP connection between workers so I don't have to reconnect every time I want to send a message? Or, is there a better solution?

You can create a connection globally in your celery task module and use it from your tasks to send messages. In that case the connection will be established at start-up and will be shared between worker processes.

import socket 
from celery.task import tasks = socket.socket(socket.AF_INET, socket.SOCK_STREAM) 
s.connect(('localhost', 9999)) @task
def echo(arg):s.send(arg) return s.recv()