httpx Can't read response in Auth.auth

The Fix

Upgrade to version 0.13.0 or later.

Based on closed encode/httpx issue #802 · 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%.

Open PR/Commit

@@ -421,6 +421,41 @@ class MyCustomAuth(httpx.Auth):
 ```
 
+Similarly, if you are implementing a scheme that requires access to the response body, then use the `requires_response_body` property.   You will then be able to access response body properties and methods such as `response.content`, `response.text`, `response.json()`, etc.
+
+```python

fix.md

Option A — Upgrade to fixed release\nUpgrade to version 0.13.0 or later.\nWhen NOT to use: This fix should not be used if the response body is not needed for authentication.\n\n

Why This Fix Works in Production

Trigger: Can't read response in Auth.auth_flow
Mechanism: The Auth class did not allow access to the response body in the auth flow
Why the fix works: Added the Auth.requires_response_body attribute to allow reading the response body in the auth flow. (first fixed release: 0.13.0).

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

The Auth class did not allow access to the response body in the auth flow
Production symptom (often without a traceback): Can't read response in Auth.auth_flow

Proof / Evidence

GitHub issue: #802
Fix PR: https://github.com/encode/httpx/pull/803
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: 0.71

Discussion

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

Jump to Sources Open on GitHub

“Hi! I assume you’d like to access the response body because the server returns an auth token as a JSON payload, eg {"token": "123abc"}, right?…”

@florimondmanca · 2020-02-03 · source

“Indeed, adding a requires_response_body attribute would make sense.”

@lovelydinosaur · 2020-02-03 · source

Failure Signature (Search String)

Can't read response in Auth.auth_flow

Copy-friendly signature

signature.txt

Failure Signature
-----------------
Can't read response in Auth.auth_flow

Error Message

Signature-only (no traceback captured)

error.txt

Error Message
-------------
Can't read response in Auth.auth_flow

What Broke

Users could not retrieve authentication tokens from server responses, causing failed authentication.

Why It Broke

The Auth class did not allow access to the response body in the auth flow

Fix Options (Details)

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

Upgrade to version 0.13.0 or later.

When NOT to use: This fix should not be used if the response body is not needed for authentication.

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/803

First fixed release: 0.13.0

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

When NOT to Use This Fix

This fix should not be used if the response body is not needed for 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.

Version Compatibility Table

Version	Status
0.13.0	Fixed

Related Issues

No related fixes found.

Cluster: httpx:configuration-error All hubs All clusters

Related clusters: Data consistency Other Timeout

Sources

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

httpx Can't read response in Auth.auth_flow (Fix)