The Fix
Upgrade to version 0.13.0 or later.
Based on closed encode/httpx issue #670 · 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%.
@@ -6,7 +6,7 @@
from urllib.request import parse_http_list
-from .exceptions import ProtocolError
+from .exceptions import ProtocolError, RequestBodyUnavailable
from .models import Request, Response
Option A — Upgrade to fixed release\nUpgrade to version 0.13.0 or later.\nWhen NOT to use: Do not use this fix if the request body must remain non-replayable.\n\n
Why This Fix Works in Production
- Trigger: DigestAuth should raise a clear error if the request cannot replay.
- Mechanism: DigestAuth implementation fails to handle non-replayable requests properly
- Why the fix works: DigestAuth now raises a RequestBodyUnavailable exception if a non-replayable request is passed. (first fixed release: 0.13.0).
- 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
- DigestAuth implementation fails to handle non-replayable requests properly
- Production symptom (often without a traceback): DigestAuth should raise a clear error if the request cannot replay.
Proof / Evidence
- GitHub issue: #670
- Fix PR: https://github.com/encode/httpx/pull/685
- First fixed release: 0.13.0
- Reproduced locally: No (not executed)
- Last verified: 2026-02-09
- Confidence: 0.85
- Did this fix it?: Yes (upstream fix exists)
- Own content ratio: 0.73
Discussion
High-signal excerpts from the issue thread (symptoms, repros, edge-cases).
“@kousikmitra Feel free to! We don’t tend to assign people to issues so feel free to go ahead and open a PR when you’d like…”
“See the client redirect code for an equivelent case with redirects. Potentially a reasonable first issue.”
Failure Signature (Search String)
- DigestAuth should raise a clear error if the request cannot replay.
- Our DigestAuth implementation cannot work with non-replayable requests.
Copy-friendly signature
Failure Signature
-----------------
DigestAuth should raise a clear error if the request cannot replay.
Our DigestAuth implementation cannot work with non-replayable requests.
Error Message
Signature-only (no traceback captured)
Error Message
-------------
DigestAuth should raise a clear error if the request cannot replay.
Our DigestAuth implementation cannot work with non-replayable requests.
What Broke
Requests with non-replayable bodies lead to unclear errors in production.
Why It Broke
DigestAuth implementation fails to handle non-replayable requests properly
Fix Options (Details)
Option A — Upgrade to fixed release Safe default (recommended)
Upgrade to version 0.13.0 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/685
First fixed release: 0.13.0
Last verified: 2026-02-09. Validate in your environment.
When NOT to Use This Fix
- Do not use this fix if the request body must remain non-replayable.
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.
Version Compatibility Table
| Version | Status |
|---|---|
| 0.13.0 | Fixed |
Related Issues
No related fixes found.
Sources
We don’t republish the full GitHub discussion text. Use the links above for context.