The Fix
Upgrade to version 0.14.2 or later.
Based on closed encode/httpx issue #1066 · 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%.
@@ -36,13 +36,13 @@
::: httpx.Client
:docstring:
- :members: headers cookies params request get head options post put patch delete build_request send close
+ :members: headers cookies params auth request get head options post put patch delete build_request send close
Option A — Upgrade to fixed release\nUpgrade to version 0.14.2 or later.\nWhen NOT to use: Do not use this fix if you require the original behavior of static authentication.\n\n
Why This Fix Works in Production
- Trigger: - [x] `self.timeout` - Looks like it should *definitely* move to a property getter / setter style, as per params/headers/cookies.
- Mechanism: Added a setter for the `Client.auth` property to allow authentication to be set using the same argument types as during client initialization.
- Why the fix works: Added a setter for the `Client.auth` property to allow authentication to be set using the same argument types as during client initialization. (first fixed release: 0.14.2).
- 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
- Production symptom (often without a traceback): - [x] `self.timeout` - Looks like it should *definitely* move to a property getter / setter style, as per params/headers/cookies.
Proof / Evidence
- GitHub issue: #1066
- Fix PR: https://github.com/encode/httpx/pull/1185
- First fixed release: 0.14.2
- Reproduced locally: No (not executed)
- Last verified: 2026-02-09
- Confidence: 0.85
- Did this fix it?: Yes (upstream fix exists)
- Own content ratio: 0.75
Discussion
High-signal excerpts from the issue thread (symptoms, repros, edge-cases).
“Dropping the milestone on this from 0.14 to 1.0, since the remaining items here are pretty minor, but we should still track them.”
Failure Signature (Search String)
- - [x] `self.timeout` - Looks like it should *definitely* move to a property getter / setter style, as per params/headers/cookies.
Copy-friendly signature
Failure Signature
-----------------
- [x] `self.timeout` - Looks like it should *definitely* move to a property getter / setter style, as per params/headers/cookies.
Error Message
Signature-only (no traceback captured)
Error Message
-------------
- [x] `self.timeout` - Looks like it should *definitely* move to a property getter / setter style, as per params/headers/cookies.
What Broke
Users could not change authentication methods after the client was created, leading to failed requests.
Fix Options (Details)
Option A — Upgrade to fixed release Safe default (recommended)
Upgrade to version 0.14.2 or later.
Use when you can deploy the upstream fix. It is usually lower-risk than long-lived workarounds.
Fix reference: https://github.com/encode/httpx/pull/1185
First fixed release: 0.14.2
Last verified: 2026-02-09. Validate in your environment.
When NOT to Use This Fix
- Do not use this fix if you require the original behavior of static authentication.
Did This Fix Work in Your Case?
Quick signal helps us prioritize which fixes to verify and improve.
Prevention
- Add a CI check that diffs key outputs after upgrades (OpenAPI schema snapshots, JSON payload shapes, CLI output).
- Upgrade behind a canary and run integration tests against the canary before 100% rollout.
- 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 |
|---|---|
| 0.14.2 | Fixed |
Related Issues
No related fixes found.
Sources
We don’t republish the full GitHub discussion text. Use the links above for context.