3.11.5

Bug fixes

• Fixed the ANY method not appearing in :meth:~aiohttp.web.UrlDispatcher.routes -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9899, #9987.

---

3.11.4

Bug fixes

• Fixed StaticResource not allowing the OPTIONS method after calling set_options_route -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9972, #9975, #9976.

Miscellaneous internal changes

• Improved performance of creating web responses when there are no cookies -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9895.

---

3.11.3

Bug fixes

• Removed non-existing __author__ from dir(aiohttp) -- by :user:Dreamsorcerer.

  Related issues and pull requests on GitHub:
  #9918.

• Restored the FlowControlDataQueue class -- by :user:bdraco.

  This class is no longer used internally, and will be permanently removed in the next major version.

  Related issues and pull requests on GitHub:
  #9963.

Miscellaneous internal changes

• Improved performance of resolving resources when multiple methods are registered for the same route -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9899.

---

3.11.2

Bug fixes

• Fixed improperly closed WebSocket connections generating an unhandled exception -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9883.

---

3.11.1

Bug fixes

• Added a backward compatibility layer to :class:aiohttp.RequestInfo to allow creating these objects without a real_url -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9873.

---

3.11.0

Bug fixes

• Raise :exc:aiohttp.ServerFingerprintMismatch exception on client-side if request through http proxy with mismatching server fingerprint digest: aiohttp.ClientSession(headers=headers, connector=TCPConnector(ssl=aiohttp.Fingerprint(mismatch_digest), trust_env=True).request(...) -- by :user:gangj.

  Related issues and pull requests on GitHub:
  #6652.

• Modified websocket :meth:aiohttp.ClientWebSocketResponse.receive_str, :py:meth:aiohttp.ClientWebSocketResponse.receive_bytes, :py:meth:aiohttp.web.WebSocketResponse.receive_str & :py:meth:aiohttp.web.WebSocketResponse.receive_bytes methods to raise new :py:exc:aiohttp.WSMessageTypeError exception, instead of generic :py:exc:TypeError, when websocket messages of incorrect types are received -- by :user:ara-25.

  Related issues and pull requests on GitHub:
  #6800.

• Made TestClient.app a Generic so type checkers will know the correct type (avoiding unneeded client.app is not None checks) -- by :user:Dreamsorcerer.

  Related issues and pull requests on GitHub:
  #8977.

• Fixed the keep-alive connection pool to be FIFO instead of LIFO -- by :user:bdraco.

  Keep-alive connections are more likely to be reused before they disconnect.

  Related issues and pull requests on GitHub:
  #9672.

Features

• Added strategy parameter to :meth:aiohttp.web.StreamResponse.enable_compression
  The value of this parameter is passed to the :func:zlib.compressobj function, allowing people
  to use a more sufficient compression algorithm for their data served by :mod:aiohttp.web
  -- by :user:shootkin

  Related issues and pull requests on GitHub:
  #6257.

• Added server_hostname parameter to ws_connect.

  Related issues and pull requests on GitHub:
  #7941.

• Exported :py:class:~aiohttp.ClientWSTimeout to top-level namespace -- by :user:Dreamsorcerer.

  Related issues and pull requests on GitHub:
  #8612.

• Added secure/httponly/samesite parameters to .del_cookie() -- by :user:Dreamsorcerer.

  Related issues and pull requests on GitHub:
  #8956.

• Updated :py:class:~aiohttp.ClientSession's auth logic to include default auth only if the request URL's origin matches _base_url; otherwise, the auth will not be included -- by :user:MaximZemskov

  Related issues and pull requests on GitHub:
  #8966, #9466.

• Added proxy and proxy_auth parameters to :py:class:~aiohttp.ClientSession -- by :user:meshya.

  Related issues and pull requests on GitHub:
  #9207.

• Added default_to_multipart parameter to FormData.

  Related issues and pull requests on GitHub:
  #9335.

• Added :py:meth:~aiohttp.ClientWebSocketResponse.send_frame and :py:meth:~aiohttp.web.WebSocketResponse.send_frame for WebSockets -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9348.

• Updated :py:class:~aiohttp.ClientSession to support paths in base_url parameter.
  base_url paths must end with a / -- by :user:Cycloctane.

  Related issues and pull requests on GitHub:
  #9530.

• Improved performance of reading WebSocket messages with a Cython implementation -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9543, #9554, #9556, #9558, #9636, #9649, #9781.

• Added writer_limit to the :py:class:~aiohttp.web.WebSocketResponse to be able to adjust the limit before the writer forces the buffer to be drained -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9572.

• Added an :attr:~aiohttp.abc.AbstractAccessLogger.enabled property to :class:aiohttp.abc.AbstractAccessLogger to dynamically check if logging is enabled -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9822.

Deprecations (removal in next major release)

• Deprecate obsolete timeout: float and receive_timeout: Optional[float] in :py:meth:~aiohttp.ClientSession.ws_connect. Change default websocket receive timeout from None to 10.0.

  Related issues and pull requests on GitHub:
  #3945.

Removals and backward incompatible breaking changes

• Dropped support for Python 3.8 -- by :user:Dreamsorcerer.

  Related issues and pull requests on GitHub:
  #8797.

• Increased minimum yarl version to 1.17.0 -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #8909, #9079, #9305, #9574.

• Removed the is_ipv6_address and is_ip4_address helpers are they are no longer used -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9344.

• Changed ClientRequest.connection_key to be a NamedTuple to improve client performance -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9365.

• FlowControlDataQueue has been replaced with the WebSocketDataQueue -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9685.

• Changed ClientRequest.request_info to be a NamedTuple to improve client performance -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9692.

Packaging updates and notes for downstreams

• Switched to using the :mod:propcache <propcache.api> package for property caching
  -- by :user:bdraco.

  The :mod:propcache <propcache.api> package is derived from the property caching
  code in :mod:yarl and has been broken out to avoid maintaining it for multiple
  projects.

  Related issues and pull requests on GitHub:
  #9394.

• Separated aiohttp.http_websocket into multiple files to make it easier to maintain -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9542, #9552.

Contributor-facing changes

• Changed diagram images generator from blockdiag to GraphViz.
  Generating documentation now requires the GraphViz executable to be included in $PATH or sphinx build configuration.

  Related issues and pull requests on GitHub:
  #9359.

Miscellaneous internal changes

• Added flake8 settings to avoid some forms of implicit concatenation. -- by :user:booniepepper.

  Related issues and pull requests on GitHub:
  #7731.

• Enabled keep-alive support on proxies (which was originally disabled several years ago) -- by :user:Dreamsorcerer.

  Related issues and pull requests on GitHub:
  #8920.

• Changed web entry point to not listen on TCP when only a Unix path is passed -- by :user:Dreamsorcerer.

  Related issues and pull requests on GitHub:
  #9033.

• Disabled automatic retries of failed requests in :class:aiohttp.test_utils.TestClient's client session
  (which could potentially hide errors in tests) -- by :user:ShubhAgarwal-dev.

  Related issues and pull requests on GitHub:
  #9141.

• Changed web keepalive_timeout default to around an hour in order to reduce race conditions on reverse proxies -- by :user:Dreamsorcerer.

  Related issues and pull requests on GitHub:
  #9285.

• Reduced memory required for stream objects created during the client request lifecycle -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9407.

• Improved performance of the internal DataQueue -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9659.

• Improved performance of calling receive for WebSockets for the most common message types -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9679.

• Replace internal helper methods method_must_be_empty_body and status_code_must_be_empty_body with simple set lookups -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9722.

• Improved performance of :py:class:aiohttp.BaseConnector when there is no limit_per_host -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9756.

• Improved performance of sending HTTP requests when there is no body -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9757.

• Improved performance of the WebsocketWriter when the protocol is not paused -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9796.

• Implemented zero copy writes for StreamWriter -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9839.

---

3.11.0rc2

Bug fixes

• Raise :exc:aiohttp.ServerFingerprintMismatch exception on client-side if request through http proxy with mismatching server fingerprint digest: aiohttp.ClientSession(headers=headers, connector=TCPConnector(ssl=aiohttp.Fingerprint(mismatch_digest), trust_env=True).request(...) -- by :user:gangj.

  Related issues and pull requests on GitHub:
  #6652.

• Modified websocket :meth:aiohttp.ClientWebSocketResponse.receive_str, :py:meth:aiohttp.ClientWebSocketResponse.receive_bytes, :py:meth:aiohttp.web.WebSocketResponse.receive_str & :py:meth:aiohttp.web.WebSocketResponse.receive_bytes methods to raise new :py:exc:aiohttp.WSMessageTypeError exception, instead of generic :py:exc:TypeError, when websocket messages of incorrect types are received -- by :user:ara-25.

  Related issues and pull requests on GitHub:
  #6800.

• Made TestClient.app a Generic so type checkers will know the correct type (avoiding unneeded client.app is not None checks) -- by :user:Dreamsorcerer.

  Related issues and pull requests on GitHub:
  #8977.

• Authentication provided by a redirect now takes precedence over provided auth when making requests with the client -- by :user:PLPeeters.

  Related issues and pull requests on GitHub:
  #9436.

• Fixed :py:meth:WebSocketResponse.close() <aiohttp.web.WebSocketResponse.close> to discard non-close messages within its timeout window after sending close -- by :user:lenard-mosys.

  Related issues and pull requests on GitHub:
  #9506.

• Fixed a deadlock that could occur while attempting to get a new connection slot after a timeout -- by :user:bdraco.

  The connector was not cancellation-safe.

  Related issues and pull requests on GitHub:
  #9670, #9671.

• Fixed the keep-alive connection pool to be FIFO instead of LIFO -- by :user:bdraco.

  Keep-alive connections are more likely to be reused before they disconnect.

  Related issues and pull requests on GitHub:
  #9672.

• Fixed the WebSocket flow control calculation undercounting with multi-byte data -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9686.

Features

• Added strategy parameter to :meth:aiohttp.web.StreamResponse.enable_compression
  The value of this parameter is passed to the :func:zlib.compressobj function, allowing people
  to use a more sufficient compression algorithm for their data served by :mod:aiohttp.web
  -- by :user:shootkin

  Related issues and pull requests on GitHub:
  #6257.

• Added server_hostname parameter to ws_connect.

  Related issues and pull requests on GitHub:
  #7941.

• Exported :py:class:~aiohttp.ClientWSTimeout to top-level namespace -- by :user:Dreamsorcerer.

  Related issues and pull requests on GitHub:
  #8612.

• Added secure/httponly/samesite parameters to .del_cookie() -- by :user:Dreamsorcerer.

  Related issues and pull requests on GitHub:
  #8956.

• Updated :py:class:~aiohttp.ClientSession's auth logic to include default auth only if the request URL's origin matches _base_url; otherwise, the auth will not be included -- by :user:MaximZemskov

  Related issues and pull requests on GitHub:
  #8966, #9466.

• Added proxy and proxy_auth parameters to :py:class:~aiohttp.ClientSession -- by :user:meshya.

  Related issues and pull requests on GitHub:
  #9207.

• Added default_to_multipart parameter to FormData.

  Related issues and pull requests on GitHub:
  #9335.

• Added :py:meth:~aiohttp.ClientWebSocketResponse.send_frame and :py:meth:~aiohttp.web.WebSocketResponse.send_frame for WebSockets -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9348.

• Updated :py:class:~aiohttp.ClientSession to support paths in base_url parameter.
  base_url paths must end with a / -- by :user:Cycloctane.

  Related issues and pull requests on GitHub:
  #9530.

• Improved performance of reading WebSocket messages with a Cython implementation -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9543, #9554, #9556, #9558, #9636, #9649, #9781.

• Added writer_limit to the :py:class:~aiohttp.web.WebSocketResponse to be able to adjust the limit before the writer forces the buffer to be drained -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9572.

• Added an :attr:~aiohttp.abc.AbstractAccessLogger.enabled property to :class:aiohttp.abc.AbstractAccessLogger to dynamically check if logging is enabled -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9822.

Deprecations (removal in next major release)

• Deprecate obsolete timeout: float and receive_timeout: Optional[float] in :py:meth:~aiohttp.ClientSession.ws_connect. Change default websocket receive timeout from None to 10.0.

  Related issues and pull requests on GitHub:
  #3945.

Removals and backward incompatible breaking changes

• Dropped support for Python 3.8 -- by :user:Dreamsorcerer.

  Related issues and pull requests on GitHub:
  #8797.

• Increased minimum yarl version to 1.17.0 -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #8909, #9079, #9305, #9574.

• Removed the is_ipv6_address and is_ip4_address helpers are they are no longer used -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9344.

• Changed ClientRequest.connection_key to be a NamedTuple to improve client performance -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9365.

• Improved performance of the connector when a connection can be reused -- by :user:bdraco.

  If BaseConnector.connect has been subclassed and replaced with custom logic, the ceil_timeout must be added.

  Related issues and pull requests on GitHub:
  #9600.

• FlowControlDataQueue has been replaced with the WebSocketDataQueue -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9685.

• Changed ClientRequest.request_info to be a NamedTuple to improve client performance -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9692.

Packaging updates and notes for downstreams

• Switched to using the :mod:propcache <propcache.api> package for property caching
  -- by :user:bdraco.

  The :mod:propcache <propcache.api> package is derived from the property caching
  code in :mod:yarl and has been broken out to avoid maintaining it for multiple
  projects.

  Related issues and pull requests on GitHub:
  #9394.

• Separated aiohttp.http_websocket into multiple files to make it easier to maintain -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9542, #9552.

Contributor-facing changes

• Changed diagram images generator from blockdiag to GraphViz.
  Generating documentation now requires the GraphViz executable to be included in $PATH or sphinx build configuration.

  Related issues and pull requests on GitHub:
  #9359.

Miscellaneous internal changes

• Added flake8 settings to avoid some forms of implicit concatenation. -- by :user:booniepepper.

  Related issues and pull requests on GitHub:
  #7731.

• Enabled keep-alive support on proxies (which was originally disabled several years ago) -- by :user:Dreamsorcerer.

  Related issues and pull requests on GitHub:
  #8920.

• Changed web entry point to not listen on TCP when only a Unix path is passed -- by :user:Dreamsorcerer.

  Related issues and pull requests on GitHub:
  #9033.

• Disabled automatic retries of failed requests in :class:aiohttp.test_utils.TestClient's client session
  (which could potentially hide errors in tests) -- by :user:ShubhAgarwal-dev.

  Related issues and pull requests on GitHub:
  #9141.

• Changed web keepalive_timeout default to around an hour in order to reduce race conditions on reverse proxies -- by :user:Dreamsorcerer.

  Related issues and pull requests on GitHub:
  #9285.

• Reduced memory required for stream objects created during the client request lifecycle -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9407.

• Improved performance of the client request lifecycle when there are no cookies -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9470.

• Improved performance of sending client requests when the writer can finish synchronously -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9485.

• Improved performance of serializing HTTP headers -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9603.

• Improved performance of the internal DataQueue -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9659.

• Improved performance of calling receive for WebSockets for the most common message types -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9679.

• Replace internal helper methods method_must_be_empty_body and status_code_must_be_empty_body with simple set lookups -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9722.

• Passing enable_cleanup_closed to :py:class:aiohttp.TCPConnector is now ignored on Python 3.12.7+ and 3.13.1+ since the underlying bug that caused asyncio to leak SSL connections has been fixed upstream -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9726, #9736.

• Improved performance of :py:class:aiohttp.BaseConnector when there is no limit_per_host -- by :user:bdraco.

  *Related issues and pull...

3.10.11

Bug fixes

• Authentication provided by a redirect now takes precedence over provided auth when making requests with the client -- by :user:PLPeeters.

  Related issues and pull requests on GitHub:
  #9436.

• Fixed :py:meth:WebSocketResponse.close() <aiohttp.web.WebSocketResponse.close> to discard non-close messages within its timeout window after sending close -- by :user:lenard-mosys.

  Related issues and pull requests on GitHub:
  #9506.

• Fixed a deadlock that could occur while attempting to get a new connection slot after a timeout -- by :user:bdraco.

  The connector was not cancellation-safe.

  Related issues and pull requests on GitHub:
  #9670, #9671.

• Fixed the WebSocket flow control calculation undercounting with multi-byte data -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9686.

• Fixed incorrect parsing of chunk extensions with the pure Python parser -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9851.

• Fixed system routes polluting the middleware cache -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9852.

Removals and backward incompatible breaking changes

• Improved performance of the connector when a connection can be reused -- by :user:bdraco.

  If BaseConnector.connect has been subclassed and replaced with custom logic, the ceil_timeout must be added.

  Related issues and pull requests on GitHub:
  #9600.

Miscellaneous internal changes

• Improved performance of the client request lifecycle when there are no cookies -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9470.

• Improved performance of sending client requests when the writer can finish synchronously -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9485.

• Improved performance of serializing HTTP headers -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9603.

• Passing enable_cleanup_closed to :py:class:aiohttp.TCPConnector is now ignored on Python 3.12.7+ and 3.13.1+ since the underlying bug that caused asyncio to leak SSL connections has been fixed upstream -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9726, #9736.

---

3.10.11rc0

Bug fixes

• Authentication provided by a redirect now takes precedence over provided auth when making requests with the client -- by :user:PLPeeters.

  Related issues and pull requests on GitHub:
  #9436.

• Fixed :py:meth:WebSocketResponse.close() <aiohttp.web.WebSocketResponse.close> to discard non-close messages within its timeout window after sending close -- by :user:lenard-mosys.

  Related issues and pull requests on GitHub:
  #9506.

• Fixed a deadlock that could occur while attempting to get a new connection slot after a timeout -- by :user:bdraco.

  The connector was not cancellation-safe.

  Related issues and pull requests on GitHub:
  #9670, #9671.

• Fixed the WebSocket flow control calculation undercounting with multi-byte data -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9686.

Removals and backward incompatible breaking changes

• Improved performance of the connector when a connection can be reused -- by :user:bdraco.

  If BaseConnector.connect has been subclassed and replaced with custom logic, the ceil_timeout must be added.

  Related issues and pull requests on GitHub:
  #9600.

Miscellaneous internal changes

• Improved performance of the client request lifecycle when there are no cookies -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9470.

• Improved performance of sending client requests when the writer can finish synchronously -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9485.

• Improved performance of serializing HTTP headers -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9603.

• Passing enable_cleanup_closed to :py:class:aiohttp.TCPConnector is now ignored on Python 3.12.7+ and 3.13.1+ since the underlying bug that caused asyncio to leak SSL connections has been fixed upstream -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9726, #9736.

---

3.11.0rc1

Bug fixes

• Raise :exc:aiohttp.ServerFingerprintMismatch exception on client-side if request through http proxy with mismatching server fingerprint digest: aiohttp.ClientSession(headers=headers, connector=TCPConnector(ssl=aiohttp.Fingerprint(mismatch_digest), trust_env=True).request(...) -- by :user:gangj.

  Related issues and pull requests on GitHub:
  #6652.

• Modified websocket :meth:aiohttp.ClientWebSocketResponse.receive_str, :py:meth:aiohttp.ClientWebSocketResponse.receive_bytes, :py:meth:aiohttp.web.WebSocketResponse.receive_str & :py:meth:aiohttp.web.WebSocketResponse.receive_bytes methods to raise new :py:exc:aiohttp.WSMessageTypeError exception, instead of generic :py:exc:TypeError, when websocket messages of incorrect types are received -- by :user:ara-25.

  Related issues and pull requests on GitHub:
  #6800.

• Made TestClient.app a Generic so type checkers will know the correct type (avoiding unneeded client.app is not None checks) -- by :user:Dreamsorcerer.

  Related issues and pull requests on GitHub:
  #8977.

• Authentication provided by a redirect now takes precedence over provided auth when making requests with the client -- by :user:PLPeeters.

  Related issues and pull requests on GitHub:
  #9436.

• Fixed :py:meth:WebSocketResponse.close() <aiohttp.web.WebSocketResponse.close> to discard non-close messages within its timeout window after sending close -- by :user:lenard-mosys.

  Related issues and pull requests on GitHub:
  #9506.

• Fixed a deadlock that could occur while attempting to get a new connection slot after a timeout -- by :user:bdraco.

  The connector was not cancellation-safe.

  Related issues and pull requests on GitHub:
  #9670, #9671.

• Fixed the keep-alive connection pool to be FIFO instead of LIFO -- by :user:bdraco.

  Keep-alive connections are more likely to be reused before they disconnect.

  Related issues and pull requests on GitHub:
  #9672.

• Fixed the WebSocket flow control calculation undercounting with multi-byte data -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9686.

Features

• Added strategy parameter to :meth:aiohttp.web.StreamResponse.enable_compression
  The value of this parameter is passed to the :func:zlib.compressobj function, allowing people
  to use a more sufficient compression algorithm for their data served by :mod:aiohttp.web
  -- by :user:shootkin

  Related issues and pull requests on GitHub:
  #6257.

• Added server_hostname parameter to ws_connect.

  Related issues and pull requests on GitHub:
  #7941.

• Exported :py:class:~aiohttp.ClientWSTimeout to top-level namespace -- by :user:Dreamsorcerer.

  Related issues and pull requests on GitHub:
  #8612.

• Added secure/httponly/samesite parameters to .del_cookie() -- by :user:Dreamsorcerer.

  Related issues and pull requests on GitHub:
  #8956.

• Updated :py:class:~aiohttp.ClientSession's auth logic to include default auth only if the request URL's origin matches _base_url; otherwise, the auth will not be included -- by :user:MaximZemskov

  Related issues and pull requests on GitHub:
  #8966, #9466.

• Added proxy and proxy_auth parameters to :py:class:~aiohttp.ClientSession -- by :user:meshya.

  Related issues and pull requests on GitHub:
  #9207.

• Added default_to_multipart parameter to FormData.

  Related issues and pull requests on GitHub:
  #9335.

• Added :py:meth:~aiohttp.ClientWebSocketResponse.send_frame and :py:meth:~aiohttp.web.WebSocketResponse.send_frame for WebSockets -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9348.

• Updated :py:class:~aiohttp.ClientSession to support paths in base_url parameter.
  base_url paths must end with a / -- by :user:Cycloctane.

  Related issues and pull requests on GitHub:
  #9530.

• Improved performance of reading WebSocket messages with a Cython implementation -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9543, #9554, #9556, #9558, #9636, #9649, #9781.

• Added writer_limit to the :py:class:~aiohttp.web.WebSocketResponse to be able to adjust the limit before the writer forces the buffer to be drained -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9572.

Deprecations (removal in next major release)

• Deprecate obsolete timeout: float and receive_timeout: Optional[float] in :py:meth:~aiohttp.ClientSession.ws_connect. Change default websocket receive timeout from None to 10.0.

  Related issues and pull requests on GitHub:
  #3945.

Removals and backward incompatible breaking changes

• Dropped support for Python 3.8 -- by :user:Dreamsorcerer.

  Related issues and pull requests on GitHub:
  #8797.

• Increased minimum yarl version to 1.17.0 -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #8909, #9079, #9305, #9574.

• Removed the is_ipv6_address and is_ip4_address helpers are they are no longer used -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9344.

• Changed ClientRequest.connection_key to be a NamedTuple to improve client performance -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9365.

• Improved performance of the connector when a connection can be reused -- by :user:bdraco.

  If BaseConnector.connect has been subclassed and replaced with custom logic, the ceil_timeout must be added.

  Related issues and pull requests on GitHub:
  #9600.

• FlowControlDataQueue has been replaced with the WebSocketDataQueue -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9685.

• Changed ClientRequest.request_info to be a NamedTuple to improve client performance -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9692.

Packaging updates and notes for downstreams

• Switched to using the :mod:propcache <propcache.api> package for property caching
  -- by :user:bdraco.

  The :mod:propcache <propcache.api> package is derived from the property caching
  code in :mod:yarl and has been broken out to avoid maintaining it for multiple
  projects.

  Related issues and pull requests on GitHub:
  #9394.

• Separated aiohttp.http_websocket into multiple files to make it easier to maintain -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9542, #9552.

Contributor-facing changes

• Changed diagram images generator from blockdiag to GraphViz.
  Generating documentation now requires the GraphViz executable to be included in $PATH or sphinx build configuration.

  Related issues and pull requests on GitHub:
  #9359.

Miscellaneous internal changes

• Added flake8 settings to avoid some forms of implicit concatenation. -- by :user:booniepepper.

  Related issues and pull requests on GitHub:
  #7731.

• Enabled keep-alive support on proxies (which was originally disabled several years ago) -- by :user:Dreamsorcerer.

  Related issues and pull requests on GitHub:
  #8920.

• Changed web entry point to not listen on TCP when only a Unix path is passed -- by :user:Dreamsorcerer.

  Related issues and pull requests on GitHub:
  #9033.

• Disabled automatic retries of failed requests in :class:aiohttp.test_utils.TestClient's client session
  (which could potentially hide errors in tests) -- by :user:ShubhAgarwal-dev.

  Related issues and pull requests on GitHub:
  #9141.

• Changed web keepalive_timeout default to around an hour in order to reduce race conditions on reverse proxies -- by :user:Dreamsorcerer.

  Related issues and pull requests on GitHub:
  #9285.

• Reduced memory required for stream objects created during the client request lifecycle -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9407.

• Improved performance of the client request lifecycle when there are no cookies -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9470.

• Improved performance of sending client requests when the writer can finish synchronously -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9485.

• Improved performance of serializing HTTP headers -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9603.

• Improved performance of the internal DataQueue -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9659.

• Improved performance of calling receive for WebSockets for the most common message types -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9679.

• Replace internal helper methods method_must_be_empty_body and status_code_must_be_empty_body with simple set lookups -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9722.

• Passing enable_cleanup_closed to :py:class:aiohttp.TCPConnector is now ignored on Python 3.12.7+ and 3.13.1+ since the underlying bug that caused asyncio to leak SSL connections has been fixed upstream -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9726, #9736.

• Improved performance of :py:class:aiohttp.BaseConnector when there is no limit_per_host -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9756.

• Improved performance of sending HTTP requests when there is no body -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9757.

---