Normalize list-style header parsing in pure-Python parser#12253
Closed
rodrigobnogueira wants to merge 2 commits intoaio-libs:masterfrom
Closed
Normalize list-style header parsing in pure-Python parser#12253rodrigobnogueira wants to merge 2 commits intoaio-libs:masterfrom
rodrigobnogueira wants to merge 2 commits intoaio-libs:masterfrom
Conversation
psf-chronographer
bot
added
the
bot:chronographer:provided
Codecov Report✅ All modified and coverable lines are covered by tests. Additional details and impacted files@@ Coverage Diff @@
## master #12253 +/- ##
==========================================
- Coverage 99.11% 99.10% -0.01%
==========================================
Files 130 130
Lines 45432 45489 +57
Branches 2400 2410 +10
==========================================
+ Hits 45028 45084 +56
Misses 273 273
- Partials 131 132 +1
Flags with carried forward coverage won't be shown. Click here to find out more. ☔ View full report in Codecov by Sentry. |
rodrigobnogueira
changed the title
rodrigobnogueira
force-pushed
the
fix-header-list-parsing-master
branch
from
8e8bc9e to
b4fc804
Compare
rodrigobnogueira
changed the title
rodrigobnogueira
force-pushed
the
fix-header-list-parsing-master
branch
from
8dd9795 to
30c7234
Compare
rodrigobnogueira
added a commit
to rodrigobnogueira/aiohttp
that referenced
this pull request
Mar 23, 2026
rodrigobnogueira
added a commit
to rodrigobnogueira/aiohttp
that referenced
this pull request
Mar 23, 2026
rodrigobnogueira
force-pushed
the
fix-header-list-parsing-master
branch
from
908082a to
5077768
Compare
5 tasks
Member
Author
|
Superseded by #12296, which targets list-headers as requested. Closing this PR to keep discussion in one place. |
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
1 participant
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
What do these changes do?
This PR fixes list-style token parsing for the
Connectionheader and related tokenized headers in the HTTP parser.The parser now normalizes comma-separated values and validates token fragments more consistently, avoiding edge-case misparsing.
Are there changes in behavior for the user?
Yes.
Malformed
Transfer-Encodingvalues are now rejected more strictly during parsing.Specifically, when parsing yields no valid transfer-coding tokens (for example because the field value is empty/invalid after normalization), the parser raises
BadHttpMessage("Request has invalid \Transfer-Encoding`")`.Previously, some malformed cases could be treated as "not chunked" and continue. The new behavior fails fast for invalid
Transfer-Encoding, which is safer and more RFC-aligned.Is it a substantial burden for the maintainers to support this?
No.
This is a focused parser correctness hardening with tests and changelog updates, and it keeps behavior consistent around invalid tokenized headers.
Related issue number
N/A
Checklist