How to fix NOGROUP No such consumer group in Redis

Before using XREADGROUP, create the consumer group using the XGROUP CREATE command. The MKSTREAM flag ensures the stream is created if it does not already exist:

XGROUP CREATE mystream mygroup $ MKSTREAM

Replace mystream with your stream key and mygroup with your desired consumer group name. The $ means new messages only; use 0 to read from the beginning.

Check that the consumer group was created successfully using XINFO GROUPS:

XINFO GROUPS mystream

This displays all consumer groups for the stream. Confirm your group name is in the list.

For production applications, implement error handling to auto-create the group on startup:

import redis

r = redis.Redis()
try:
    r.xgroup_create('mystream', 'mygroup', id='$', mkstream=True)
except redis.exceptions.ResponseError as e:
    if 'BUSYGROUP' in str(e):
        pass  # Group already exists, that's fine
    else:
        raise

This catches the BUSYGROUP error (which means the group already exists) and continues safely.

Ensure you are using the correct stream key and group name consistently across your codebase. Redis is case-sensitive, so mygroup and MyGroup are different. Use XINFO GROUPS or XINFO STREAM to verify which streams and groups actually exist.