Redis publish - Wrong number of argument for 'set'

Question

I'm trying to use websockets with Django for small parts of my application.

Trying the first example to broadcast a message with django-websocket-redis

from ws4redis.publisher import RedisPublisher
redis_publisher = RedisPublisher(facility='foobar', broadcast=True)
redis_publisher.publish_message('Hello World')

I'm actually receiving the message into subscribed clients but I'm getting this error:

wrong number of arguments for 'set' command [...] Exception location my_virtualenv/local/lib/python2.7/site-packages/redis/connection.py in read_response, line 344

(traced from the publish_message() call)

My versions:

Django==1.6.2
django-websocket-redis==0.4.0
redis==2.9.1

Can someone help me to debug that ?

Answer 1

I finally set the expiration time to 0 as a workaround

WS4REDIS_EXPIRE = 0

This prevents ws4redis to store anything in redis.

---

Fixed since 0.4.1

Answer 2

Looks like it's a bug.

Fix:

in ws4redis.redis_store.RedisStore in publish_message, change

self._connection.set(channel, message, ex=expire)

to

self._connection.setex(channel, expire, message)

the redis SET command does not take a 3rd argument. What I believe was meant was to set a value that expires after a number of seconds, which is the redis SETEX command. The py-redis setex method is called like setex(name, time, value).

This resolves the "Wrong number of argument for 'set'" error.

ref: https://github.com/jrief/django-websocket-redis/pull/30