Critical. Celery=5.2.2 does not create a connection to the Redis Sentinel when using kombu=5.6.1 #2420
Description
This morning, while updating, I came across an error in celery. After investigation, I found out that the error is due to yesterday's release of kombu=5.6.1. When rolling back to the kombu version=5.5.4. Everything is working.
- Python 3.10.19
- Celery 5.2.2
- Kombu 5.6.1
- Redis Sentinel Cluster
- Docker python:3.10-slim-bookworm
Log:
[CRITICAL] 26/11/2025 05:34:42 - Unrecoverable error: TypeError('NoneType takes no arguments')
Traceback (most recent call last):
File "/usr/local/lib/python3.10/site-packages/kombu/transport/virtual/base.py", line 951, in create_channel
return self._avail_channels.pop()
IndexError: pop from empty list
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "/usr/local/lib/python3.10/site-packages/celery/worker/worker.py", line 203, in start
self.blueprint.start(self)
File "/usr/local/lib/python3.10/site-packages/celery/bootsteps.py", line 116, in start
step.start(parent)
File "/usr/local/lib/python3.10/site-packages/celery/bootsteps.py", line 365, in start
return self.obj.start()
File "/usr/local/lib/python3.10/site-packages/celery/worker/consumer/consumer.py", line 326, in start
blueprint.start(self)
File "/usr/local/lib/python3.10/site-packages/celery/bootsteps.py", line 116, in start
step.start(parent)
File "/usr/local/lib/python3.10/site-packages/celery/worker/consumer/connection.py", line 21, in start
c.connection = c.connect()
File "/usr/local/lib/python3.10/site-packages/celery/worker/consumer/consumer.py", line 422, in connect
conn = self.connection_for_read(heartbeat=self.amqheartbeat)
File "/usr/local/lib/python3.10/site-packages/celery/worker/consumer/consumer.py", line 428, in connection_for_read
return self.ensure_connected(
File "/usr/local/lib/python3.10/site-packages/celery/worker/consumer/consumer.py", line 454, in ensure_connected
conn = conn.ensure_connection(
File "/usr/local/lib/python3.10/site-packages/kombu/connection.py", line 408, in ensure_connection
self._ensure_connection(*args, **kwargs)
File "/usr/local/lib/python3.10/site-packages/kombu/connection.py", line 461, in _ensure_connection
return retry_over_time(
File "/usr/local/lib/python3.10/site-packages/kombu/utils/functional.py", line 318, in retry_over_time
return fun(*args, **kwargs)
File "/usr/local/lib/python3.10/site-packages/kombu/connection.py", line 941, in _connection_factory
self._connection = self._establish_connection()
File "/usr/local/lib/python3.10/site-packages/kombu/connection.py", line 863, in _establish_connection
conn = self.transport.establish_connection()
File "/usr/local/lib/python3.10/site-packages/kombu/transport/virtual/base.py", line 975, in establish_connection
self._avail_channels.append(self.create_channel(self))
File "/usr/local/lib/python3.10/site-packages/kombu/transport/virtual/base.py", line 953, in create_channel
channel = self.Channel(connection)
File "/usr/local/lib/python3.10/site-packages/kombu/transport/redis.py", line 757, in __init__
self.client.ping()
File "/usr/local/lib/python3.10/site-packages/kombu/utils/objects.py", line 40, in __get__
return super().__get__(instance, owner)
File "/usr/local/lib/python3.10/functools.py", line 981, in __get__
val = self.func(instance)
File "/usr/local/lib/python3.10/site-packages/kombu/transport/redis.py", line 1304, in client
return self._create_client(asynchronous=True)
File "/usr/local/lib/python3.10/site-packages/kombu/transport/redis.py", line 1260, in _create_client
return self.Client(connection_pool=self.async_pool)
File "/usr/local/lib/python3.10/site-packages/kombu/transport/redis.py", line 1298, in async_pool
self._async_pool = self._get_pool(asynchronous=True)
File "/usr/local/lib/python3.10/site-packages/kombu/transport/redis.py", line 1487, in _get_pool
params = self._connparams(asynchronous=asynchronous)
File "/usr/local/lib/python3.10/site-packages/kombu/transport/redis.py", line 1245, in _connparams
class Connection(connection_cls):
TypeError: NoneType takes no arguments