redis-py invoke devenv throws "Not Found for url: (Fix)

The Fix

pip install redis==7.1.0

Based on closed redis/redis-py issue #1768 · PR/commit linked

Production note: Most teams hit this during upgrades or environment changes. Roll out with a canary and smoke critical endpoints (health, OpenAPI/docs) before 100%.

Jump to Verify Open PR/Commit

@@ -73,7 +73,7 @@ healtcheck_cmd = python -c "import socket;print(True) if 0 == socket.socket(sock
 [docker:lots-of-pythons]
 name = lots-of-pythons
-image = redisfab/lots-of-pythons
+image = redisfab/lots-of-pythons:latest
 volumes =

verify

Re-run: invoke tests
Re-run: invoke clean
Re-run: groups

fix.md

Option A — Upgrade to fixed release\npip install redis==7.1.0\nWhen NOT to use: Do not use this fix if you require a specific version of the Docker image.\n\n

Why This Fix Works in Production

Trigger: Error: No such container: master
Mechanism: Locking the latest tag for the pythons docker to resolve the issue with missing images.
Why the fix works: Locking the latest tag for the pythons docker to resolve the issue with missing images. (first fixed release: 7.1.0).

Production impact:

If left unfixed, the same config can fail only in production (env differences), causing startup failures or partial feature outages.

Why This Breaks in Prod

Triggered by an upgrade/regression window: 3.6 breaks; 7.1.0 is the first fixed release.
Shows up under Python 3.7.10 in real deployments (not just unit tests).
Surfaces as: Error: No such container: master

Proof / Evidence

GitHub issue: #1768
Fix PR: https://github.com/redis/redis-py/pull/1769
First fixed release: 7.1.0
Affected versions: 3.6
Reproduced locally: No (not executed)
Last verified: 2026-02-09
Confidence: 0.85
Did this fix it?: Yes (upstream fix exists)
Own content ratio: 0.19

Discussion

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

Jump to Sources Open on GitHub

“Reopened pending feedback. But the PR merged to master should address and close this.”

@chayim · 2021-12-02 · confirmation · source

“I forgot to mention the docker version. It's version 20.10.7, build f0df350 on Amazon Linux 2. Thanks you for the quick response. The invoke devenv…”

@santosh · 2021-12-03 · source

“Can you do me a favour and remove all your docker images, as well as restarting the docker daemon? I can't reproduce this unfortunately :(”

@chayim · 2021-12-03 · source

“Taking this a step further, can you also run _invoke clean_? It may be that you have dockers in a strange state - so please…”

@chayim · 2021-12-03 · source

Failure Signature (Search String)

Error: No such container: master

Error Message

Stack trace

error.txt

Error Message
-------------
Error: No such container: master
Error: No such container: replica
Error: No such container: sentinel_1
Error: No such container: sentinel_2
Error: No such container: sentinel_3
Error: No such container: redismod
Error: No such container: lots-of-pythons
devenv installed: astor==0.8.1,attrs==21.2.0,backports.entry-points-selectable==1.1.1,black==21.11b1,certifi==2021.10.8,charset-normalizer==2.0.8,click==8.0.3,coverage==6.2,distlib==0.3.3,docker==5.0.3,filelock==3.4.0,flake8==4.0.1,flynt==0.69,idna==3.3,importlib-metadata==4.2.0,iniconfig==1.1.1,invoke==1.6.0,isort==5.10.1,mccabe==0.6.1,mypy-extensions==0.4.3,packaging==21.3,pathspec==0.9.0,platformdirs==2.4.0,pluggy==1.0.0,py==1.11.0,pycodestyle==2.8.0,pyflakes==2.4.0,pyparsing==3.0.6,pytest==6.2.5,pytest-cov==3.0.0,pytest-timeout==2.0.1,regex==2021.11.10,requests==2.26.0,six==1.16.0,toml==0.10.2,tomli==1.2.2,tox==3.24.4,tox-docker==3.1.0,typed-ast==1.5.0,typing_extensions==4.0.1,ujson==4.3.0,urllib3==1.26.7,virtualenv==20.10.0,vulture==2.3,websocket-client==1.2.1,zipp==3.6.0
devenv docker: pull 'redisfab/redis-py:6.2.6-buster' (from 'master')
___________________________________ summary ____________________________________
  devenv: commands succeeded
  congratulations :)
Traceback (most recent call last):
  File "/efs/repos/redis-py/.venv/lib64/python3.7/site-packages/docker/api/client.py", line 268, in _raise_for_status
...
... (truncated) ...

Stack trace

error.txt

Error Message
-------------
$ invoke tests
Starting Redis tests
GLOB sdist-make: /efs/repos/redis-py/setup.py
standalone-plain inst-nodeps: /efs/repos/redis-py/.tox/.tmp/package/2/redis-4.1.0rc2.zip
standalone-plain installed: astor==0.8.1,attrs==21.2.0,backports.entry-points-selectable==1.1.1,black==21.11b1,certifi==2021.10.8,charset-normalizer==2.0.8,click==8.0.3,coverage==6.2,Deprecated==1.2.3,distlib==0.3.3,docker==5.0.3,filelock==3.4.0,flake8==4.0.1,flynt==0.69,idna==3.3,importlib-metadata==4.2.0,iniconfig==1.1.1,invoke==1.6.0,isort==5.10.1,mccabe==0.6.1,mypy-extensions==0.4.3,packaging==21.3,pathspec==0.9.0,platformdirs==2.4.0,pluggy==1.0.0,py==1.11.0,pycodestyle==2.8.0,pyflakes==2.4.0,pyparsing==3.0.6,pytest==6.2.5,pytest-cov==3.0.0,pytest-timeout==2.0.1,redis @ file:///efs/repos/redis-py/.tox/.tmp/package/2/redis-4.1.0rc2.zip,regex==2021.11.10,requests==2.26.0,six==1.16.0,toml==0.10.2,tomli==1.2.2,tox==3.24.4,tox-docker==3.1.0,typed-ast==1.5.0,typing_extensions==4.0.1,ujson==4.3.0,urllib3==1.26.7,virtualenv==20.10.0,vulture==2.3,websocket-client==1.2.1,wrapt==1.13.3,zipp==3.6.0
standalone-plain docker: run 'redisfab/redis-py:6.2.6-buster' (from 'master')
___________________________________ summary ____________________________________
  standalone-plain: commands succeeded
ERROR:   standalone-hiredis: undefined
ERROR:   cluster-plain: undefined
ERROR:   cluster-hiredis: undefined
Traceback (most re
... (truncated) ...

Stack trace

error.txt

Error Message
-------------
$ invoke clean
master
replica
sentinel_1
sentinel_2
sentinel_3
redismod
lots-of-pythons
redis_cluster
(.venv) ec2-user at ip-10-2-1-250 in /efs/repos/redis-py (master)
$ groups
ec2-user adm wheel systemd-journal docker
(.venv) ec2-user at ip-10-2-1-250 in /efs/repos/redis-py (master)
$ invoke devenv
Error: No such container: master
Error: No such container: replica
Error: No such container: sentinel_1
Error: No such container: sentinel_2
Error: No such container: sentinel_3
Error: No such container: redismod
Error: No such container: lots-of-pythons
Error: No such container: redis_cluster
devenv installed: astor==0.8.1,attrs==21.2.0,backports.entry-points-selectable==1.1.1,black==21.11b1,certifi==2021.10.8,charset-normalizer==2.0.8,click==8.0.3,coverage==6.2,distlib==0.3.3,docker==5.0.3,filelock==3.4.0,flake8==4.0.1,flynt==0.69,idna==3.3,importlib-metadata==4.2.0,iniconfig==1.1.1,invoke==1.6.0,isort==5.10.1,mccabe==0.6.1,mypy-extensions==0.4.3,packaging==21.3,pathspec==0.9.0,platformdirs==2.4.0,pluggy==1.0.0,py==1.11.0,pycodestyle==2.8.0,pyflakes==2.4.0,pyparsing==3.0.6,pytest==6.2.5,pytest-cov==3.0.0,pytest-timeout==2.0.1,regex==2021.11.10,requests==2.26.0,six==1.16.0,toml==0.10.2,tomli==1.2.2,tox==3.24.4,tox-docker==3.1.0,typed-ast==1.5.0,typing_extensions==4.0.1,ujson==4.3.0,urllib3==1.26.7,virtualenv==20.10.0,vulture==2.3,websocket-client==1.2.1,zipp==3.6.0
devenv docker: r
... (truncated) ...

Environment

Python: 3.7.10

What Broke

The development environment setup fails, preventing local development and testing.

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 you require a specific version of the Docker image.

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

Option D — Guard side-effects with OnceOnly Guardrail for side-effects

Mitigate duplicate external side-effects under retries/timeouts/agent loops by gating the operation before calling external systems.

Place OnceOnly between your code/agent and real side-effects (Stripe, emails, CRM, APIs).
Use a stable key per side-effect (e.g., customer_id + action + idempotency_key).
Fail-safe: configure fail-open vs fail-closed based on blast radius and spend risk.

Show example snippet (optional)

onceonly.py

from onceonly import OnceOnly
import os

once = OnceOnly(api_key=os.environ["ONCEONLY_API_KEY"], fail_open=True)

# Stable idempotency key per real side-effect.
# Use a request id / job id / webhook delivery id / Stripe event id, etc.
event_id = "evt_..."  # replace
key = f"stripe:webhook:{event_id}"

res = once.check_lock(key=key, ttl=3600)
if res.duplicate:
    return {"status": "already_processed"}

# Safe to execute the side-effect exactly once.
handle_event(event_id)

See OnceOnly SDK

When NOT to use: Do not use this to hide logic bugs or data corruption. Use it to block duplicate external side-effects and enforce tool permissions/spend caps.

Fix reference: https://github.com/redis/redis-py/pull/1769

First fixed release: 7.1.0

Last verified: 2026-02-09. Validate in your environment.

When NOT to Use This Fix

Do not use this fix if you require a specific version of the Docker image.
Do not use this to hide logic bugs or data corruption. Use it to block duplicate external side-effects and enforce tool permissions/spend caps.

Verify Fix

verify

Re-run: invoke tests
Re-run: invoke clean
Re-run: groups

Did This Fix Work in Your Case?

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

Prevention

Make timeouts explicit and test them (unit + integration) to avoid silent behavior changes.
Instrument retries (attempt count + reason) and alert on spikes to catch dependency slowdowns.

Version Compatibility Table

Version	Status
3.6	Broken
7.1.0	Fixed

Related Issues

No related fixes found.

Cluster: redis-py:configuration-error redis-py hub redis-py best practices All hubs All clusters

Related clusters: Retry storm Data consistency Race condition

Sources

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

redis-py invoke devenv throws "Not Found for url: (Fix)

The Fix

Why This Fix Works in Production

Why This Breaks in Prod

Proof / Evidence

Discussion

Failure Signature (Search String)

Error Message

Environment

What Broke

Fix Options (Details)

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

Option D — Guard side-effects with OnceOnly Guardrail for side-effects

Get updates

When NOT to Use This Fix

Verify Fix

Did This Fix Work in Your Case?

Prevention

Version Compatibility Table

Related Issues

Sources