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.

---

3.11.0rc0

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.

• 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.

• 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.

---

3.11.0b5

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.

• 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.

• 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:
  #9...

3.11.0b4

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.

• 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.

• 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.

---

Performance

aiohttp 3.10.0 yarl 1.9.5

aiohttp 3.11.0b0 yarl 1.17.0

aiohttp 3.11.0b4 yarl 1.17.1

3.11.0b3

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 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.

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.

• 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.

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.

---

Performance

WebSocket reader performance has improved ~10% since b2

aiohttp 3.10.0 yarl 1.9.5

aiohttp 3.11.0b0 yarl 1.17.0

aiohttp 3.11.0b1 yarl 1.17.1 (no change from b1/b2)

3.11.0b2

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.

• 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.

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.

• 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.

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.

---

Performance

WebSocket reader performance has improved ~60% since b1

aiohttp 3.10.0 yarl 1.9.5

aiohttp 3.11.0b0 yarl 1.17.0

aiohttp 3.11.0b1 yarl 1.17.1 (no change from b1)

3.11.0b1

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.

• 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.

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.

• 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.

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.

---

Performance

aiohttp 3.10.0 yarl 1.9.5

aiohttp 3.11.0b0 yarl 1.17.0

aiohttp 3.11.0b1 yarl 1.17.1

3.11.0b0

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.

• 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.

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.

• 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.

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

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

• 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.

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.

---

Performance

aiohttp 3.10.0 yarl 1.9.5

aiohttp 3.11.0b0 yarl 1.17.0

3.10.10

Bug fixes

• Fixed error messages from :py:class:~aiohttp.resolver.AsyncResolver being swallowed -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9451, #9455.

Features

• Added :exc:aiohttp.ClientConnectorDNSError for differentiating DNS resolution errors from other connector errors -- by :user:mstojcevich.

  Related issues and pull requests on GitHub:
  #8455.

Miscellaneous internal changes

• Simplified DNS resolution throttling code to reduce chance of race conditions -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9454.

---

3.10.9

Bug fixes

• Fixed proxy headers being used in the ConnectionKey hash when a proxy was not being used -- by :user:bdraco.

  If default headers are used, they are also used for proxy headers. This could have led to creating connections that were not needed when one was already available.

  Related issues and pull requests on GitHub:
  #9368.

• Widened the type of the trace_request_ctx parameter of
  :meth:ClientSession.request() <aiohttp.ClientSession.request> and friends
  -- by :user:layday.

  Related issues and pull requests on GitHub:
  #9397.

Removals and backward incompatible breaking changes

• Fixed failure to try next host after single-host connection timeout -- by :user:brettdh.

  The default client :class:aiohttp.ClientTimeout params has changed to include a sock_connect timeout of 30 seconds so that this correct behavior happens by default.

  Related issues and pull requests on GitHub:
  #7342.

Miscellaneous internal changes

• Improved performance of resolving hosts with Python 3.12+ -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9342.

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

  Related issues and pull requests on GitHub:
  #9406.

---