4.0

New issue

Open

No due date

•Last updated Sep 2, 2026

A cut-off for pending deprecations.

No schedule date yet, the milestone is a mark for API removal issues.

50% complete

Can't specify both fingerprint and SSLContext for client request
aio-libs/aiohttp#3679 · opened on Apr 5, 2019 · 4.0
7
Trailer headers
aio-libs/aiohttp#1652 · opened on Feb 17, 2017 · 4.0
9
Add test utils for testing ClientSession
aio-libs/aiohttp#1704 · opened on Mar 8, 2017 · 4.0
14
Response content is omitted if it is erroneous
aio-libs/aiohttp#1843 · opened on Apr 26, 2017 · 4.0
7
ConnectionResetError when close browser, but not all static files was fetch
aio-libs/aiohttp#1893 · opened on May 16, 2017 · 4.0
4
Introduce session.make_request() API
aio-libs/aiohttp#2019 · opened on Jun 26, 2017 · 4.0
3
Add custom header support to websocket client
aio-libs/aiohttp#2053 · opened on Jul 4, 2017 · 4.0
8
Send explicit RuntimeError on response operations after session closing
aio-libs/aiohttp#2202 · opened on Aug 15, 2017 · 4.0
1
Response not passed to WSServerHandshakeError
aio-libs/aiohttp#2279 · opened on Sep 20, 2017 · 4.0
9
Cannot easily access max_field_size in client response
aio-libs/aiohttp#2304 · opened on Oct 7, 2017 · 4.0
5
WebSocketResponse's timeout does not apply to send_bytes/send_json/send_str calls.
aio-libs/aiohttp#2310 · opened on Oct 10, 2017 · 4.0
2
access subapp routes via <app-name>:<route-name>
aio-libs/aiohttp#2314 · opened on Oct 11, 2017 · 4.0
12
prepared URL API
aio-libs/aiohttp#2516 · opened on Nov 13, 2017 · 4.0
6
Add custom header support to websocket client
Unread
#4607 opened Mar 3, 2020 · Updated Jul 18, 2026Draft
7
Refactor client SSL transports cleanup
Unread
#5102 opened Oct 22, 2020 · Updated Aug 22, 2023Draft
1
[Discussion] Ordering of middlewares=
aio-libs/aiohttp#6798 · opened on Jun 20, 2022 · 4.0
Handling static URLs
aio-libs/aiohttp#7940 · opened on Dec 4, 2023 · 4.0
1
WebSocketResponse requires closing/closed checks before sending something
aio-libs/aiohttp#3391 · opened on Nov 16, 2018 · 4.0
3
Send 100-continue only when handler reads body
aio-libs/aiohttp#8877 · opened on Aug 25, 2024 · 4.0
Wrong URL parsing in redirect
aio-libs/aiohttp#6626 · opened on Feb 18, 2022 · 4.0
12
Revert cookie changes in Python 3.15
aio-libs/aiohttp#11400 · opened on Aug 9, 2025 · 4.0
4
Alternative to passing router to the application?
Feature
aio-libs/aiohttp#11840 · opened on Dec 15, 2025 · 4.0
7
Fix type error with pytest-aiohttp
aio-libs/aiohttp#12495 · opened on May 10, 2026 · 4.0
Check lru_cache usage in v4
aio-libs/aiohttp#12916 · opened on Jun 13, 2026 · 4.0
Add support for HTTP/2
Unread
#13039 opened Jul 2, 2026 · Updated Nov 14, 2026Draft
169

Navigation Menu

4.0

Can't specify both fingerprint and SSLContext for client request

Trailer headers

Add test utils for testing ClientSession

Response content is omitted if it is erroneous

ConnectionResetError when close browser, but not all static files was fetch

Introduce `session.make_request()` API

Add custom header support to websocket client

Send explicit RuntimeError on response operations after session closing

Response not passed to WSServerHandshakeError

Cannot easily access max_field_size in client response

WebSocketResponse's timeout does not apply to send_bytes/send_json/send_str calls.

access subapp routes via <app-name>:<route-name>

prepared URL API

Add custom header support to websocket client

Refactor client SSL transports cleanup

[Discussion] Ordering of middlewares=

Handling static URLs

WebSocketResponse requires closing/closed checks before sending something

Send 100-continue only when handler reads body

Wrong URL parsing in redirect

Revert cookie changes in Python 3.15

Alternative to passing router to the application?

Fix type error with pytest-aiohttp

Check lru_cache usage in v4

Add support for HTTP/2

Issues