3.14.1

Bug fixes

• Fixed a race condition in :py:class:~aiohttp.TCPConnector where closing the connector while a DNS resolution was in-flight could raise :py:exc:AttributeError instead of :py:exc:~aiohttp.ClientConnectionError -- by :user:goingforstudying-ctrl.

  Related issues and pull requests on GitHub:
  #12497.

• Fixed CancelledError not closing a connection -- by :user:aiolibsbot.

  Related issues and pull requests on GitHub:
  #12795.

• Tightened up some websocket parser checks -- by :user:Dreamsorcerer.

  Related issues and pull requests on GitHub:
  #12817.

• Fixed :class:~aiohttp.CookieJar dropping the host-only flag of cookies when persisted with :meth:~aiohttp.CookieJar.save and reloaded with :meth:~aiohttp.CookieJar.load, so a cookie set without a Domain attribute is again scoped to the exact host that set it after a reload; the absolute expiration deadline is now persisted as well, so a reloaded cookie keeps its original lifetime instead of being rescheduled from the load time. :meth:~aiohttp.CookieJar.load now replaces the jar contents rather than merging onto prior state, and loaded cookies pass through the same acceptance rules as :meth:~aiohttp.CookieJar.update_cookies, so a cookie for an IP-address host is dropped when loaded into a jar created without unsafe=True -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #12824.

• Scoped :class:~aiohttp.DigestAuthMiddleware credentials to the origin of the first request it handles, so a redirect to a different origin no longer triggers a digest response computed from the configured credentials; a challenge from another origin is only answered when that origin falls within a protection space advertised by the anchor origin through the RFC 7616 domain directive -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #12825.

• Fixed the C HTTP parser not enforcing max_line_size on a request target or response reason phrase that is split across multiple reads; each fragment was checked on its own, so an accumulated line could exceed the limit without raising LineTooLong. The accumulated length is now checked, matching the pure-Python parser -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #12826.

• Changed :class:~aiohttp.TCPConnector to reject legacy non-canonical numeric IPv4 host forms such as 2130706433, 017700000001 and 127.1 with :exc:~aiohttp.InvalidUrlClientError; only canonical dotted-quad IPv4 literals are now treated as IP address literals, while every other host is sent through the configured resolver -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #12827.

• Fixed :meth:~aiohttp.StreamReader.readany and :meth:~aiohttp.StreamReader.read_nowait joining data fed back into the buffer during the call (when draining below the low water mark resumes reading) into a single unbounded :class:bytes; a call now returns only the chunks that were buffered when it started, keeping the drain of an unread auto-decompressed request body bounded by the read buffer -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #12828.

• Bounded the number of parsed-but-unhandled pipelined HTTP/1 requests buffered per connection on the server; once the queue reaches an internal limit the parser stops emitting and the transport is paused, resuming as the request handler drains the queue, so a client keeping one handler busy can no longer accumulate an unbounded backlog of pipelined requests -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #12830.

• Fixed :meth:aiohttp.web.Response.write_eof skipping Payload.close() when the body write was interrupted by an error or cancellation, for example when a client disconnects mid-response; the payload close hook now runs in a finally so a :class:~aiohttp.payload.Payload body always releases its resources -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #12831.

• Fixed the pure-Python HTTP parser not enforcing max_line_size on a chunk-size line when the whole line arrived in a single read; the limit was only applied to chunk-size metadata split across reads. The complete-line case is now checked too, matching the split-line behavior -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #12832.

• Included the per-request server_hostname override in the :class:~aiohttp.TCPConnector connection pool key, so a pooled TLS connection is no longer reused for a request that sets server_hostname to a different value -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #12835.

---

3.14.0

We have a new website! https://aio-libs.org
Subscribe to the news feed to find out more about what we're working on in future.

Features

• Added RequestKey and ResponseKey classes,
  which enable static type checking for request & response
  context storages in the same way that AppKey does for Application
  -- by :user:gsoldatov.

  Related issues and pull requests on GitHub:
  #11766.

• Added :func:~aiohttp.encode_basic_auth for encoding HTTP Basic
  Authentication credentials. Replaces the now-deprecated
  :class:~aiohttp.BasicAuth -- by :user:Dreamsorcerer.

  Related issues and pull requests on GitHub:
  #12499.

• Started accepting :term:asynchronous context managers <asynchronous context manager> for cleanup contexts.
  Legacy single-yield :term:asynchronous generator cleanup contexts continue to be
  supported; async context managers are adapted internally so they are
  entered at startup and exited during cleanup.

  -- by :user:MannXo.

  Related issues and pull requests on GitHub:
  #11681.

• Added :py:attr:~aiohttp.CookieJar.cookies and :py:attr:~aiohttp.CookieJar.host_only_cookies read-only properties to :py:class:~aiohttp.CookieJar exposing the stored cookies with their full attributes -- by :user:Br1an67.

  Related issues and pull requests on GitHub:
  #3951.

• Added :py:attr:~aiohttp.web.TCPSite.port accessor for dynamic port allocations in :class:~aiohttp.web.TCPSite -- by :user:twhittock-disguise and :user:rodrigobnogueira.

  Related issues and pull requests on GitHub:
  #10665.

• Added decode_text parameter to :meth:~aiohttp.ClientSession.ws_connect and :class:~aiohttp.web.WebSocketResponse to receive WebSocket TEXT messages as raw bytes instead of decoded strings, enabling direct use with high-performance JSON parsers like orjson -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #11763, #11764.

• Large overhaul of parser/decompression code.

  The zip bomb security fix in 3.13 stopped highly compressed payloads
  from being decompressed, regardless of validity. Now aiohttp will
  decompress such payloads in chunks of 256+ KiB, allowing safe decompression
  of such payloads.

  -- by :user:Dreamsorcerer.

  Related issues and pull requests on GitHub:
  #11966.

• Added explicit APIs for bytes-returning JSON serializer:
  JSONBytesEncoder type, JsonBytesPayload,
  :func:~aiohttp.web.json_bytes_response,
  :meth:~aiohttp.web.WebSocketResponse.send_json_bytes and
  :meth:~aiohttp.ClientWebSocketResponse.send_json_bytes methods, and
  json_serialize_bytes parameter for :class:~aiohttp.ClientSession
  -- by :user:kevinpark1217.

  Related issues and pull requests on GitHub:
  #11989.

• Added :attr:~aiohttp.ClientResponse.output_size and
  :attr:~aiohttp.ClientResponse.upload_complete -- by :user:Dreamsorcerer.

  Related issues and pull requests on GitHub:
  #12452.

Bug fixes

• Fixed ZLibDecompressor silently dropping data past the first
  member when decompressing concatenated gzip/deflate streams. Each subsequent
  member is now handed to a fresh decompressor, matching the behaviour already
  implemented for ZSTD multi-frame streams.

  -- by :user:Ashutosh-177

  Related issues and pull requests on GitHub:
  #7157.

• Improved the parser error message shown when TLS handshake bytes are received on an HTTP port -- by :user:puneetdixit200.

  Related issues and pull requests on GitHub:
  #10142.

• Fixed the C parser failing to reject a response with a body when none was expected -- by :user:Dreamsorcerer.

  Related issues and pull requests on GitHub:
  #10587.

• Fixed http parser not rejecting HTTP/1.1 requests that do not have valid Host header.
  -- by :user:Cycloctane.

  Related issues and pull requests on GitHub:
  #10600.

• Fixed misleading TLS-in-TLS warning being emitted when sending HTTPS requests through an HTTP proxy. The warning now only fires when the proxy itself uses HTTPS, which is the only case where TLS-in-TLS actually applies -- by :user:wavebyrd.

  Related issues and pull requests on GitHub:
  #10683.

• Fixed AssertionError when the transport is None during WebSocket
  preparation or file response sending (e.g. when a client disconnects
  immediately after connecting). A ConnectionResetError is now raised
  instead -- by :user:agners.

  Related issues and pull requests on GitHub:
  #11761.

• Fixed ad-hoc cookies passed to individual requests not being sent when the session's cookie jar has unsafe=True and the target URL uses an IP address, by copying the unsafe setting from the session's cookie jar to the temporary cookie jar -- by :user:Krishnachaitanyakc.

  Related issues and pull requests on GitHub:
  #12011.

• Reset the WebSocket heartbeat timer on inbound data to avoid false ping/pong timeouts while receiving large frames
  -- by :user:hoffmang9.

  Related issues and pull requests on GitHub:
  #12030.

• Switched :py:meth:~aiohttp.CookieJar.save to use JSON format and
  :py:meth:~aiohttp.CookieJar.load to try JSON first with a fallback to
  a restricted pickle unpickler -- by :user:YuvalElbar6.

  Related issues and pull requests on GitHub:
  #12091.

• Fixed redirects with consumed non-rewindable request bodies to raise
  :class:aiohttp.ClientPayloadError instead of silently sending an empty body.

  Related issues and pull requests on GitHub:
  #12195.

• Fixed zstd decompression failing with ClientPayloadError when the server
  sends a response as multiple zstd frames -- by :user:josu-moreno.

  Related issues and pull requests on GitHub:
  #12234.

• Fixed spurious Future exception was never retrieved warning on disconnect during back-pressure -- by :user:availov.

  Related issues and pull requests on GitHub:
  #12281.

• Cookiejar.save() now uses 0x600 permissions to better protect them from being read by other users -- by :user:digiscrypt.

  Related issues and pull requests on GitHub:
  #12312.

• Fixed a crash (:external+python:exc:~http.cookies.CookieError) in the cookie parser when receiving cookies
  containing ASCII control characters on CPython builds with the :cve:2026-3644
  patch. The parser now gracefully skips cookies whose value contains control
  characters instead of letting the exception propagate -- by :user:rodrigobnogueira.

  Related issues and pull requests on GitHub:
  #12395.

• Fixed digest authentication failing for requests whose path or query string contains percent-encoded reserved characters; the digest signature now uses the encoded request-target that is sent on the wire instead of the decoded form -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #12436.

• Fixed :func:aiohttp.web.run_app losing inner traceback frames when an
  exception is raised during application startup (e.g. inside
  cleanup_ctx or on_startup). Regression since 3.10.6.

  Related issues and pull requests on GitHub:
  #12493.

• Fixed per-request cookies not being dropped on cross-origin redirects -- by :user:Dreamsorcerer.

  Related issues and pull requests on GitHub:
  #12550.

• Fixed invalid bytes being allowed in multipart/payload headers -- by :user:Dreamsorcerer.

  Related issues and pull requests on GitHub:
  #12719.

• Fixed :py:meth:~aiohttp.FormData.add_field accepting invalid bytes in name and filename -- by :user:Dreamsorcerer.

  Related issues and pull requests on GitHub:
  #12721.

• Fixed websocket upgrade occurring when header contained a value like notupgrade -- by :user:Dreamsorcerer.

  Related issues and pull requests on GitHub:
  #12723.

Deprecations (removal in next major release)

• Deprecated :class:~aiohttp.BasicAuth and the auth / proxy_auth
  parameters. They will be removed in aiohttp 4.0. Use the new
  :func:~aiohttp.encode_basic_auth helper together with
  headers={"Authorization": ...} (or
  proxy_headers={"Proxy-Authorization": ...} for proxies) instead.
  Note that encode_basic_auth() defaults to utf-8, not latin1
  -- by :user:Dreamsorcerer.

  Related issues and pull requests on GitHub:
  #12499.

• Added deprecation warning to aiohttp.pytest_plugin, please switch to pytest-aiohttp -- by :user:Dreamsorcerer.

  Related issues and pull requests on GitHub:
  #10785.

Removals and backward incompatible breaking changes

• Stopped calling :func:socket.getfqdn as the fallback for
  :attr:aiohttp.web.BaseRequest.host. :func:socket.getfqdn
  performs blocking reverse DNS resolution on the event loop
  thread and can stall a worker for many seconds when the system
  resolver is slow, and could be triggered remotely by an HTTP/1.0
  request that omits the Host header. The fallback when no
  Host header is present is now the local socket address the
  request arrived on (transport sockname), or an empty string
  if no transport information is available. Code that relied on
  the FQDN being returned must now read it from
  :func:socket.getfqdn directly, off the event loop
  -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #9308, #12597.

• Dropped support for Python 3.9 -- by :user:Dreamsorcerer.

  Related issues and pull requests on GitHub:
  #11601.

• Tightened outbound header serialization to reject all ASCII control
  characters forbidden by :rfc:9110#section-5.5 and :rfc:9112#section-4
  (0x00-0x08, 0x0A-0x1F, 0x7F) in status lines,
  header field-names, and field-values. Previously only CR, LF and NUL were
  rejected. HTAB (0x09) remains permitted in field values. Applications
  ...

3.13.5

Bug fixes

• Skipped the duplicate singleton header check in lax mode (the default for response
  parsing). In strict mode (request parsing, or -X dev), all RFC 9110 singletons
  are still enforced -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #12302.

---

3.13.4

Features

• Added max_headers parameter to limit the number of headers that should be read from a response -- by :user:Dreamsorcerer.

  Related issues and pull requests on GitHub:
  #11955.

• Added a dns_cache_max_size parameter to TCPConnector to limit the size of the cache -- by :user:Dreamsorcerer.

  Related issues and pull requests on GitHub:
  #12106.

Bug fixes

• Fixed server hanging indefinitely when chunked transfer encoding chunk-size
  does not match actual data length. The server now raises
  TransferEncodingError instead of waiting forever for data that will
  never arrive -- by :user:Fridayai700.

  Related issues and pull requests on GitHub:
  #10596.

• Fixed access log timestamps ignoring daylight saving time (DST) changes. The
  previous implementation used :py:data:time.timezone which is a constant and
  does not reflect DST transitions -- by :user:nightcityblade.

  Related issues and pull requests on GitHub:
  #11283.

• Fixed RuntimeError: An event loop is running error when using aiohttp.GunicornWebWorker
  or aiohttp.GunicornUVLoopWebWorker on Python >=3.14.
  -- by :user:Tasssadar.

  Related issues and pull requests on GitHub:
  #11701.

• Fixed :exc:ValueError when creating a TLS connection with ClientTimeout(total=0) by converting 0 to None before passing to ssl_handshake_timeout in :py:meth:asyncio.loop.start_tls -- by :user:veeceey.

  Related issues and pull requests on GitHub:
  #11859.

• Restored :py:meth:~aiohttp.BodyPartReader.decode as a synchronous method
  for backward compatibility. The method was inadvertently changed to async
  in 3.13.3 as part of the decompression bomb security fix. A new
  :py:meth:~aiohttp.BodyPartReader.decode_iter method is now available
  for non-blocking decompression of large payloads using an async generator.
  Internal aiohttp code uses the async variant to maintain security protections.

  Changed multipart processing chunk sizes from 64 KiB to 256KiB, to better
  match aiohttp internals
  -- by :user:bdraco and :user:Dreamsorcerer.

  Related issues and pull requests on GitHub:
  #11898.

• Fixed false-positive :py:class:DeprecationWarning for passing enable_cleanup_closed=True to :py:class:~aiohttp.TCPConnector specifically on Python 3.12.7.
  -- by :user:Robsdedude.

  Related issues and pull requests on GitHub:
  #11972.

• Fixed _sendfile_fallback over-reading beyond requested count -- by :user:bysiber.

  Related issues and pull requests on GitHub:
  #12096.

• Fixed digest auth dropping challenge fields with empty string values -- by :user:bysiber.

  Related issues and pull requests on GitHub:
  #12097.

• ClientConnectorCertificateError.os_error no longer raises :exc:AttributeError
  -- by :user:themylogin.

  Related issues and pull requests on GitHub:
  #12136.

• Adjusted pure-Python request header value validation to align with RFC 9110 control-character handling, while preserving lax response parser behavior, and added regression tests for Host/header control-character cases.
  -- by :user:rodrigobnogueira.

  Related issues and pull requests on GitHub:
  #12231.

• Rejected duplicate singleton headers (Host, Content-Type,
  Content-Length, etc.) in the C extension HTTP parser to match
  the pure Python parser behaviour, preventing potential host-based
  access control bypasses via parser differentials
  -- by :user:rodrigobnogueira.

  Related issues and pull requests on GitHub:
  #12240.

• Aligned the pure-Python HTTP request parser with the C parser by splitting
  comma-separated and repeated Connection header values for keep-alive,
  close, and upgrade handling -- by :user:rodrigobnogueira.

  Related issues and pull requests on GitHub:
  #12249.

Improved documentation

• Documented :exc:asyncio.TimeoutError for WebSocketResponse.receive()
  and related methods -- by :user:veeceey.

  Related issues and pull requests on GitHub:
  #12042.

Packaging updates and notes for downstreams

• Upgraded llhttp to 3.9.1 -- by :user:Dreamsorcerer.

  Related issues and pull requests on GitHub:
  #12069.

Contributor-facing changes

• The benchmark CI job now runs only in the upstream repository -- by :user:Cycloctane.

  It used to always fail in forks, which this change fixed.

  Related issues and pull requests on GitHub:
  #11737.

• Fixed flaky performance tests by using appropriate fixed thresholds that account for CI variability -- by :user:rodrigobnogueira.

  Related issues and pull requests on GitHub:
  #11992.

Miscellaneous internal changes

• Fixed test_invalid_idna to work with idna 3.11 by using an invalid character (\u0080) that is rejected by yarl during URL construction -- by :user:rodrigobnogueira.

  Related issues and pull requests on GitHub:
  #12027.

• Fixed race condition in test_data_file on Python 3.14 free-threaded builds -- by :user:rodrigobnogueira.

  Related issues and pull requests on GitHub:
  #12170.

---

3.13.3

This release contains fixes for several vulnerabilities. It is advised to
upgrade as soon as possible.

Bug fixes

• Fixed proxy authorization headers not being passed when reusing a connection, which caused 407 (Proxy authentication required) errors
  -- by :user:GLeurquin.

  Related issues and pull requests on GitHub:
  #2596.

• Fixed multipart reading failing when encountering an empty body part -- by :user:Dreamsorcerer.

  Related issues and pull requests on GitHub:
  #11857.

• Fixed a case where the parser wasn't raising an exception for a websocket continuation frame when there was no initial frame in context.

  Related issues and pull requests on GitHub:
  #11862.

Removals and backward incompatible breaking changes

• Brotli and brotlicffi minimum version is now 1.2.
  Decompression now has a default maximum output size of 32MiB per decompress call -- by :user:Dreamsorcerer.

  Related issues and pull requests on GitHub:
  #11898.

Packaging updates and notes for downstreams

• Moved dependency metadata from :file:setup.cfg to :file:pyproject.toml per :pep:621
  -- by :user:cdce8p.

  Related issues and pull requests on GitHub:
  #11643.

Contributor-facing changes

• Removed unused update-pre-commit github action workflow -- by :user:Cycloctane.

  Related issues and pull requests on GitHub:
  #11689.

Miscellaneous internal changes

• Optimized web server performance when access logging is disabled by reducing time syscalls -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #10713.

• Added regression test for cached logging status -- by :user:meehand.

  Related issues and pull requests on GitHub:
  #11778.

---

3.13.2

Bug fixes

• Fixed cookie parser to continue parsing subsequent cookies when encountering a malformed cookie that fails regex validation, such as Google's g_state cookie with unescaped quotes -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #11632.

• Fixed loading netrc credentials from the default :file:~/.netrc (:file:~/_netrc on Windows) location when the :envvar:NETRC environment variable is not set -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #11713, #11714.

• Fixed WebSocket compressed sends to be cancellation safe. Tasks are now shielded during compression to prevent compressor state corruption. This ensures that the stateful compressor remains consistent even when send operations are cancelled -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #11725.

---

3.13.1

Features

• Make configuration options in AppRunner also available in run_app()
  -- by :user:Cycloctane.

  Related issues and pull requests on GitHub:
  #11633.

Bug fixes

• Switched to backports.zstd for Python <3.14 and fixed zstd decompression for chunked zstd streams -- by :user:ZhaoMJ.

  Note: Users who installed zstandard for support on Python <3.14 will now need to install
  backports.zstd instead (installing aiohttp[speedups] will do this automatically).

  Related issues and pull requests on GitHub:
  #11623.

• Updated Content-Type header parsing to return application/octet-stream when header contains invalid syntax.
  See :rfc:9110#section-8.3-5.

  -- by :user:sgaist.

  Related issues and pull requests on GitHub:
  #10889.

• Fixed Python 3.14 support when built without zstd support -- by :user:JacobHenner.

  Related issues and pull requests on GitHub:
  #11603.

• Fixed blocking I/O in the event loop when using netrc authentication by moving netrc file lookup to an executor -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #11634.

• Fixed routing to a sub-application added via .add_domain() not working
  if the same path exists on the parent app. -- by :user:Dreamsorcerer.

  Related issues and pull requests on GitHub:
  #11673.

Packaging updates and notes for downstreams

• Moved core packaging metadata from :file:setup.cfg to :file:pyproject.toml per :pep:621
  -- by :user:cdce8p.

  Related issues and pull requests on GitHub:
  #9951.

---

3.13.0

Features

• Added support for Python 3.14.

  Related issues and pull requests on GitHub:
  #10851, #10872.

• Added support for free-threading in Python 3.14+ -- by :user:kumaraditya303.

  Related issues and pull requests on GitHub:
  #11466, #11464.

• Added support for Zstandard (aka Zstd) compression
  -- by :user:KGuillaume-chaps.

  Related issues and pull requests on GitHub:
  #11161.

• Added StreamReader.total_raw_bytes to check the number of bytes downloaded
  -- by :user:robpats.

  Related issues and pull requests on GitHub:
  #11483.

Bug fixes

• Fixed pytest plugin to not use deprecated :py:mod:asyncio policy APIs.

  Related issues and pull requests on GitHub:
  #10851.

• Updated Content-Disposition header parsing to handle trailing semicolons and empty parts
  -- by :user:PLPeeters.

  Related issues and pull requests on GitHub:
  #11243.

• Fixed saved CookieJar failing to be loaded if cookies have partitioned flag when
  http.cookie does not have partitioned cookies supports. -- by :user:Cycloctane.

  Related issues and pull requests on GitHub:
  #11523.

Improved documentation

• Added Wireup to third-party libraries -- by :user:maldoinc.

  Related issues and pull requests on GitHub:
  #11233.

Packaging updates and notes for downstreams

• The blockbuster test dependency is now optional; the corresponding test fixture is disabled when it is unavailable
  -- by :user:musicinybrain.

  Related issues and pull requests on GitHub:
  #11363.

• Added riscv64 build to releases -- by :user:eshattow.

  Related issues and pull requests on GitHub:
  #11425.

Contributor-facing changes

• Fixed test_send_compress_text failing when alternative zlib implementation
  is used. (zlib-ng in python 3.14 windows build) -- by :user:Cycloctane.

  Related issues and pull requests on GitHub:
  #11546.

---

3.12.15

Bug fixes

• Fixed :class:~aiohttp.DigestAuthMiddleware to preserve the algorithm case from the server's challenge in the authorization response. This improves compatibility with servers that perform case-sensitive algorithm matching (e.g., servers expecting algorithm=MD5-sess instead of algorithm=MD5-SESS)
  -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #11352.

Improved documentation

• Remove outdated contents of aiohttp-devtools and aiohttp-swagger
  from Web_advanced docs.
  -- by :user:Cycloctane

  Related issues and pull requests on GitHub:
  #11347.

Packaging updates and notes for downstreams

• Started including the llhttp :file:LICENSE file in wheels by adding vendor/llhttp/LICENSE to license-files in :file:setup.cfg -- by :user:threexc.

  Related issues and pull requests on GitHub:
  #11226.

Contributor-facing changes

• Updated a regex in test_aiohttp_request_coroutine for Python 3.14.

  Related issues and pull requests on GitHub:
  #11271.

---

3.12.14

Bug fixes

• Fixed file uploads failing with HTTP 422 errors when encountering 307/308 redirects, and 301/302 redirects for non-POST methods, by preserving the request body when appropriate per :rfc:9110#section-15.4.3-3.1 -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #11270.

• Fixed :py:meth:ClientSession.close() <aiohttp.ClientSession.close> hanging indefinitely when using HTTPS requests through HTTP proxies -- by :user:bdraco.

  Related issues and pull requests on GitHub:
  #11273.

• Bumped minimum version of aiosignal to 1.4+ to resolve typing issues -- by :user:Dreamsorcerer.

  Related issues and pull requests on GitHub:
  #11280.

Features

• Added initial trailer parsing logic to Python HTTP parser -- by :user:Dreamsorcerer.

  Related issues and pull requests on GitHub:
  #11269.

Improved documentation

• Clarified exceptions raised by WebSocketResponse.send_frame et al.
  -- by :user:DoctorJohn.

  Related issues and pull requests on GitHub:
  #11234.

---