redis-py exception in listen (Fix)

The Fix

pip install redis==7.1.0

Based on closed redis/redis-py issue #1788 · PR/commit linked

Jump to Verify Open PR/Commit

@@ -1530,6 +1530,8 @@ def handle_message(self, response, ignore_subscribe_messages=False):
         message being returned.
         """
+        if response is None:
+            return None
         message_type = str_if_bytes(response[0])

repro.py

import time
import redis
db = redis.from_url('redis://redis_server', health_check_interval=1.0)
ps = db.pubsub(ignore_subscribe_messages=True)
ps.subscribe('CHANNEL_NOT_EXISTS')
time.sleep(2)
for msg in ps.listen():
    print(msg)

verify

Re-run the minimal reproduction on your broken version, then apply the fix and re-run.

fix.md

Option A — Upgrade to fixed release\npip install redis==7.1.0\nWhen NOT to use: Do not use this fix if the application relies on receiving None responses.\n\n

Why This Fix Works in Production

Trigger: for msg in ps.listen():
Mechanism: The listen method raises an exception when a health-check response is received as None
Why the fix works: Fixes an exception raised in the listen method when a health-check response is received. (first fixed release: 7.1.0).

Why This Breaks in Prod

Shows up under Python 3.9 in real deployments (not just unit tests).
The listen method raises an exception when a health-check response is received as None
Surfaces as: Traceback (most recent call last):

Proof / Evidence

GitHub issue: #1788
Fix PR: https://github.com/redis/redis-py/pull/1823
First fixed release: 7.1.0
Reproduced locally: No (not executed)
Last verified: 2026-02-07
Confidence: 0.95
Did this fix it?: Yes (upstream fix exists)
Own content ratio: 0.53

Discussion

High-signal excerpts from the issue thread (symptoms, repros, edge-cases).

Jump to Sources Open on GitHub

“will raise exception: parse_response returns None, since the first response is a health-check response. Happens on 3.5.2 and 4.0.2 fix is straight forward:”

Issue thread · issue description · source

Failure Signature (Search String)

for msg in ps.listen():

Error Message

Stack trace

error.txt

Error Message
-------------
Traceback (most recent call last):
  File "test_listen.py", line 7, in <module>
    for msg in ps.listen():
  File ".../lib/python3.9/site-packages/redis/client.py", line 3605, in listen
    response = self.handle_message(self.parse_response(block=True))
  File ".../lib/python3.9/site-packages/redis/client.py", line 3635, in handle_message
    message_type = nativestr(response[0])
TypeError: 'NoneType' object is not subscriptable

Minimal Reproduction

repro.py

import time
import redis
db = redis.from_url('redis://redis_server', health_check_interval=1.0)
ps = db.pubsub(ignore_subscribe_messages=True)
ps.subscribe('CHANNEL_NOT_EXISTS')
time.sleep(2)
for msg in ps.listen():
    print(msg)

Environment

Python: 3.9

What Broke

The application crashes with a TypeError when attempting to listen for messages.

Why It Broke

The listen method raises an exception when a health-check response is received as None

Fix Options (Details)

Option A — Upgrade to fixed release Safe default (recommended)

pip install redis==7.1.0

When NOT to use: Do not use this fix if the application relies on receiving None responses.

Use when you can deploy the upstream fix. It is usually lower-risk than long-lived workarounds.

Fix reference: https://github.com/redis/redis-py/pull/1823

First fixed release: 7.1.0

Last verified: 2026-02-07. Validate in your environment.

When NOT to Use This Fix

Do not use this fix if the application relies on receiving None responses.

Verify Fix

verify

Re-run the minimal reproduction on your broken version, then apply the fix and re-run.

Did This Fix Work in Your Case?

Quick signal helps us prioritize which fixes to verify and improve.

Prevention

Capture the exact failing error string in logs and tests so you can reproduce via a minimal script.
Pin production dependencies and upgrade only with a reproducible test that hits the failing path.

Version Compatibility Table

Version	Status
7.1.0	Fixed

Related Issues

No related fixes found.

Cluster: redis-py:other redis-py hub redis-py best practices All hubs All clusters

Related clusters: Configuration error Retry storm Data consistency

Sources

We don’t republish the full GitHub discussion text. Use the links above for context.