chore: 添加虚拟环境到仓库

- 添加 backend_service/venv 虚拟环境
- 包含所有Python依赖包
- 注意：虚拟环境约393MB，包含12655个文件

backend_service/venv/lib/python3.13/site-packages/aiohttp/_websocket/.hash/mask.pxd.hash

@@ -0,0 +1 @@
+b01999d409b29bd916e067bc963d5f2d9ee63cfc9ae0bccb769910131417bf93  /home/runner/work/aiohttp/aiohttp/aiohttp/_websocket/mask.pxd

backend_service/venv/lib/python3.13/site-packages/aiohttp/_websocket/.hash/mask.pyx.hash

@@ -0,0 +1 @@
+0478ceb55d0ed30ef1a7da742cd003449bc69a07cf9fdb06789bd2b347cbfffe  /home/runner/work/aiohttp/aiohttp/aiohttp/_websocket/mask.pyx

backend_service/venv/lib/python3.13/site-packages/aiohttp/_websocket/.hash/reader_c.pxd.hash

@@ -0,0 +1 @@
+9e5fe78ed0ebce5414d2b8e01868d90c1facc20b84d2d5ff6c23e86e44a155ae  /home/runner/work/aiohttp/aiohttp/aiohttp/_websocket/reader_c.pxd

backend_service/venv/lib/python3.13/site-packages/aiohttp/_websocket/__init__.py

@@ -0,0 +1 @@
+"""WebSocket protocol versions 13 and 8."""

backend_service/venv/lib/python3.13/site-packages/aiohttp/_websocket/helpers.py

@@ -0,0 +1,147 @@
+"""Helpers for WebSocket protocol versions 13 and 8."""
+
+import functools
+import re
+from struct import Struct
+from typing import TYPE_CHECKING, Final, List, Optional, Pattern, Tuple
+
+from ..helpers import NO_EXTENSIONS
+from .models import WSHandshakeError
+
+UNPACK_LEN3 = Struct("!Q").unpack_from
+UNPACK_CLOSE_CODE = Struct("!H").unpack
+PACK_LEN1 = Struct("!BB").pack
+PACK_LEN2 = Struct("!BBH").pack
+PACK_LEN3 = Struct("!BBQ").pack
+PACK_CLOSE_CODE = Struct("!H").pack
+PACK_RANDBITS = Struct("!L").pack
+MSG_SIZE: Final[int] = 2**14
+MASK_LEN: Final[int] = 4
+
+WS_KEY: Final[bytes] = b"258EAFA5-E914-47DA-95CA-C5AB0DC85B11"
+
+
+# Used by _websocket_mask_python
+@functools.lru_cache
+def _xor_table() -> List[bytes]:
+    return [bytes(a ^ b for a in range(256)) for b in range(256)]
+
+
+def _websocket_mask_python(mask: bytes, data: bytearray) -> None:
+    """Websocket masking function.
+
+    `mask` is a `bytes` object of length 4; `data` is a `bytearray`
+    object of any length. The contents of `data` are masked with `mask`,
+    as specified in section 5.3 of RFC 6455.
+
+    Note that this function mutates the `data` argument.
+
+    This pure-python implementation may be replaced by an optimized
+    version when available.
+
+    """
+    assert isinstance(data, bytearray), data
+    assert len(mask) == 4, mask
+
+    if data:
+        _XOR_TABLE = _xor_table()
+        a, b, c, d = (_XOR_TABLE[n] for n in mask)
+        data[::4] = data[::4].translate(a)
+        data[1::4] = data[1::4].translate(b)
+        data[2::4] = data[2::4].translate(c)
+        data[3::4] = data[3::4].translate(d)
+
+
+if TYPE_CHECKING or NO_EXTENSIONS:  # pragma: no cover
+    websocket_mask = _websocket_mask_python
+else:
+    try:
+        from .mask import _websocket_mask_cython  # type: ignore[import-not-found]
+
+        websocket_mask = _websocket_mask_cython
+    except ImportError:  # pragma: no cover
+        websocket_mask = _websocket_mask_python
+
+
+_WS_EXT_RE: Final[Pattern[str]] = re.compile(
+    r"^(?:;\s*(?:"
+    r"(server_no_context_takeover)|"
+    r"(client_no_context_takeover)|"
+    r"(server_max_window_bits(?:=(\d+))?)|"
+    r"(client_max_window_bits(?:=(\d+))?)))*$"
+)
+
+_WS_EXT_RE_SPLIT: Final[Pattern[str]] = re.compile(r"permessage-deflate([^,]+)?")
+
+
+def ws_ext_parse(extstr: Optional[str], isserver: bool = False) -> Tuple[int, bool]:
+    if not extstr:
+        return 0, False
+
+    compress = 0
+    notakeover = False
+    for ext in _WS_EXT_RE_SPLIT.finditer(extstr):
+        defext = ext.group(1)
+        # Return compress = 15 when get `permessage-deflate`
+        if not defext:
+            compress = 15
+            break
+        match = _WS_EXT_RE.match(defext)
+        if match:
+            compress = 15
+            if isserver:
+                # Server never fail to detect compress handshake.
+                # Server does not need to send max wbit to client
+                if match.group(4):
+                    compress = int(match.group(4))
+                    # Group3 must match if group4 matches
+                    # Compress wbit 8 does not support in zlib
+                    # If compress level not support,
+                    # CONTINUE to next extension
+                    if compress > 15 or compress < 9:
+                        compress = 0
+                        continue
+                if match.group(1):
+                    notakeover = True
+                # Ignore regex group 5 & 6 for client_max_window_bits
+                break
+            else:
+                if match.group(6):
+                    compress = int(match.group(6))
+                    # Group5 must match if group6 matches
+                    # Compress wbit 8 does not support in zlib
+                    # If compress level not support,
+                    # FAIL the parse progress
+                    if compress > 15 or compress < 9:
+                        raise WSHandshakeError("Invalid window size")
+                if match.group(2):
+                    notakeover = True
+                # Ignore regex group 5 & 6 for client_max_window_bits
+                break
+        # Return Fail if client side and not match
+        elif not isserver:
+            raise WSHandshakeError("Extension for deflate not supported" + ext.group(1))
+
+    return compress, notakeover
+
+
+def ws_ext_gen(
+    compress: int = 15, isserver: bool = False, server_notakeover: bool = False
+) -> str:
+    # client_notakeover=False not used for server
+    # compress wbit 8 does not support in zlib
+    if compress < 9 or compress > 15:
+        raise ValueError(
+            "Compress wbits must between 9 and 15, zlib does not support wbits=8"
+        )
+    enabledext = ["permessage-deflate"]
+    if not isserver:
+        enabledext.append("client_max_window_bits")
+
+    if compress < 15:
+        enabledext.append("server_max_window_bits=" + str(compress))
+    if server_notakeover:
+        enabledext.append("server_no_context_takeover")
+    # if client_notakeover:
+    #     enabledext.append('client_no_context_takeover')
+    return "; ".join(enabledext)

backend_service/venv/lib/python3.13/site-packages/aiohttp/_websocket/mask.pxd

@@ -0,0 +1,3 @@
+"""Cython declarations for websocket masking."""
+
+cpdef void _websocket_mask_cython(bytes mask, bytearray data)

backend_service/venv/lib/python3.13/site-packages/aiohttp/_websocket/mask.pyx

@@ -0,0 +1,48 @@
+from cpython cimport PyBytes_AsString
+
+
+#from cpython cimport PyByteArray_AsString # cython still not exports that
+cdef extern from "Python.h":
+    char* PyByteArray_AsString(bytearray ba) except NULL
+
+from libc.stdint cimport uint32_t, uint64_t, uintmax_t
+
+
+cpdef void _websocket_mask_cython(bytes mask, bytearray data):
+    """Note, this function mutates its `data` argument
+    """
+    cdef:
+        Py_ssize_t data_len, i
+        # bit operations on signed integers are implementation-specific
+        unsigned char * in_buf
+        const unsigned char * mask_buf
+        uint32_t uint32_msk
+        uint64_t uint64_msk
+
+    assert len(mask) == 4
+
+    data_len = len(data)
+    in_buf = <unsigned char*>PyByteArray_AsString(data)
+    mask_buf = <const unsigned char*>PyBytes_AsString(mask)
+    uint32_msk = (<uint32_t*>mask_buf)[0]
+
+    # TODO: align in_data ptr to achieve even faster speeds
+    # does it need in python ?! malloc() always aligns to sizeof(long) bytes
+
+    if sizeof(size_t) >= 8:
+        uint64_msk = uint32_msk
+        uint64_msk = (uint64_msk << 32) | uint32_msk
+
+        while data_len >= 8:
+            (<uint64_t*>in_buf)[0] ^= uint64_msk
+            in_buf += 8
+            data_len -= 8
+
+
+    while data_len >= 4:
+        (<uint32_t*>in_buf)[0] ^= uint32_msk
+        in_buf += 4
+        data_len -= 4
+
+    for i in range(0, data_len):
+        in_buf[i] ^= mask_buf[i]

backend_service/venv/lib/python3.13/site-packages/aiohttp/_websocket/models.py

@@ -0,0 +1,84 @@
+"""Models for WebSocket protocol versions 13 and 8."""
+
+import json
+from enum import IntEnum
+from typing import Any, Callable, Final, NamedTuple, Optional, cast
+
+WS_DEFLATE_TRAILING: Final[bytes] = bytes([0x00, 0x00, 0xFF, 0xFF])
+
+
+class WSCloseCode(IntEnum):
+    OK = 1000
+    GOING_AWAY = 1001
+    PROTOCOL_ERROR = 1002
+    UNSUPPORTED_DATA = 1003
+    ABNORMAL_CLOSURE = 1006
+    INVALID_TEXT = 1007
+    POLICY_VIOLATION = 1008
+    MESSAGE_TOO_BIG = 1009
+    MANDATORY_EXTENSION = 1010
+    INTERNAL_ERROR = 1011
+    SERVICE_RESTART = 1012
+    TRY_AGAIN_LATER = 1013
+    BAD_GATEWAY = 1014
+
+
+class WSMsgType(IntEnum):
+    # websocket spec types
+    CONTINUATION = 0x0
+    TEXT = 0x1
+    BINARY = 0x2
+    PING = 0x9
+    PONG = 0xA
+    CLOSE = 0x8
+
+    # aiohttp specific types
+    CLOSING = 0x100
+    CLOSED = 0x101
+    ERROR = 0x102
+
+    text = TEXT
+    binary = BINARY
+    ping = PING
+    pong = PONG
+    close = CLOSE
+    closing = CLOSING
+    closed = CLOSED
+    error = ERROR
+
+
+class WSMessage(NamedTuple):
+    type: WSMsgType
+    # To type correctly, this would need some kind of tagged union for each type.
+    data: Any
+    extra: Optional[str]
+
+    def json(self, *, loads: Callable[[Any], Any] = json.loads) -> Any:
+        """Return parsed JSON data.
+
+        .. versionadded:: 0.22
+        """
+        return loads(self.data)
+
+
+# Constructing the tuple directly to avoid the overhead of
+# the lambda and arg processing since NamedTuples are constructed
+# with a run time built lambda
+# https://github.com/python/cpython/blob/d83fcf8371f2f33c7797bc8f5423a8bca8c46e5c/Lib/collections/__init__.py#L441
+WS_CLOSED_MESSAGE = tuple.__new__(WSMessage, (WSMsgType.CLOSED, None, None))
+WS_CLOSING_MESSAGE = tuple.__new__(WSMessage, (WSMsgType.CLOSING, None, None))
+
+
+class WebSocketError(Exception):
+    """WebSocket protocol parser error."""
+
+    def __init__(self, code: int, message: str) -> None:
+        self.code = code
+        super().__init__(code, message)
+
+    def __str__(self) -> str:
+        return cast(str, self.args[1])
+
+
+class WSHandshakeError(Exception):
+    """WebSocket protocol handshake error."""

backend_service/venv/lib/python3.13/site-packages/aiohttp/_websocket/reader.py

@@ -0,0 +1,31 @@
+"""Reader for WebSocket protocol versions 13 and 8."""
+
+from typing import TYPE_CHECKING
+
+from ..helpers import NO_EXTENSIONS
+
+if TYPE_CHECKING or NO_EXTENSIONS:  # pragma: no cover
+    from .reader_py import (
+        WebSocketDataQueue as WebSocketDataQueuePython,
+        WebSocketReader as WebSocketReaderPython,
+    )
+
+    WebSocketReader = WebSocketReaderPython
+    WebSocketDataQueue = WebSocketDataQueuePython
+else:
+    try:
+        from .reader_c import (  # type: ignore[import-not-found]
+            WebSocketDataQueue as WebSocketDataQueueCython,
+            WebSocketReader as WebSocketReaderCython,
+        )
+
+        WebSocketReader = WebSocketReaderCython
+        WebSocketDataQueue = WebSocketDataQueueCython
+    except ImportError:  # pragma: no cover
+        from .reader_py import (
+            WebSocketDataQueue as WebSocketDataQueuePython,
+            WebSocketReader as WebSocketReaderPython,
+        )
+
+        WebSocketReader = WebSocketReaderPython
+        WebSocketDataQueue = WebSocketDataQueuePython

backend_service/venv/lib/python3.13/site-packages/aiohttp/_websocket/reader_c.pxd

@@ -0,0 +1,110 @@
+import cython
+
+from .mask cimport _websocket_mask_cython as websocket_mask
+
+
+cdef unsigned int READ_HEADER
+cdef unsigned int READ_PAYLOAD_LENGTH
+cdef unsigned int READ_PAYLOAD_MASK
+cdef unsigned int READ_PAYLOAD
+
+cdef int OP_CODE_NOT_SET
+cdef int OP_CODE_CONTINUATION
+cdef int OP_CODE_TEXT
+cdef int OP_CODE_BINARY
+cdef int OP_CODE_CLOSE
+cdef int OP_CODE_PING
+cdef int OP_CODE_PONG
+
+cdef int COMPRESSED_NOT_SET
+cdef int COMPRESSED_FALSE
+cdef int COMPRESSED_TRUE
+
+cdef object UNPACK_LEN3
+cdef object UNPACK_CLOSE_CODE
+cdef object TUPLE_NEW
+
+cdef object WSMsgType
+cdef object WSMessage
+
+cdef object WS_MSG_TYPE_TEXT
+cdef object WS_MSG_TYPE_BINARY
+
+cdef set ALLOWED_CLOSE_CODES
+cdef set MESSAGE_TYPES_WITH_CONTENT
+
+cdef tuple EMPTY_FRAME
+cdef tuple EMPTY_FRAME_ERROR
+
+cdef class WebSocketDataQueue:
+
+    cdef unsigned int _size
+    cdef public object _protocol
+    cdef unsigned int _limit
+    cdef object _loop
+    cdef bint _eof
+    cdef object _waiter
+    cdef object _exception
+    cdef public object _buffer
+    cdef object _get_buffer
+    cdef object _put_buffer
+
+    cdef void _release_waiter(self)
+
+    cpdef void feed_data(self, object data, unsigned int size)
+
+    @cython.locals(size="unsigned int")
+    cdef _read_from_buffer(self)
+
+cdef class WebSocketReader:
+
+    cdef WebSocketDataQueue queue
+    cdef unsigned int _max_msg_size
+
+    cdef Exception _exc
+    cdef bytearray _partial
+    cdef unsigned int _state
+
+    cdef int _opcode
+    cdef bint _frame_fin
+    cdef int _frame_opcode
+    cdef list _payload_fragments
+    cdef Py_ssize_t _frame_payload_len
+
+    cdef bytes _tail
+    cdef bint _has_mask
+    cdef bytes _frame_mask
+    cdef Py_ssize_t _payload_bytes_to_read
+    cdef unsigned int _payload_len_flag
+    cdef int _compressed
+    cdef object _decompressobj
+    cdef bint _compress
+
+    cpdef tuple feed_data(self, object data)
+
+    @cython.locals(
+        is_continuation=bint,
+        fin=bint,
+        has_partial=bint,
+        payload_merged=bytes,
+    )
+    cpdef void _handle_frame(self, bint fin, int opcode, object payload, int compressed) except *
+
+    @cython.locals(
+        start_pos=Py_ssize_t,
+        data_len=Py_ssize_t,
+        length=Py_ssize_t,
+        chunk_size=Py_ssize_t,
+        chunk_len=Py_ssize_t,
+        data_len=Py_ssize_t,
+        data_cstr="const unsigned char *",
+        first_byte="unsigned char",
+        second_byte="unsigned char",
+        f_start_pos=Py_ssize_t,
+        f_end_pos=Py_ssize_t,
+        has_mask=bint,
+        fin=bint,
+        had_fragments=Py_ssize_t,
+        payload_bytearray=bytearray,
+    )
+    cpdef void _feed_data(self, bytes data) except *

backend_service/venv/lib/python3.13/site-packages/aiohttp/_websocket/reader_c.py

@@ -0,0 +1,476 @@
+"""Reader for WebSocket protocol versions 13 and 8."""
+
+import asyncio
+import builtins
+from collections import deque
+from typing import Deque, Final, Optional, Set, Tuple, Union
+
+from ..base_protocol import BaseProtocol
+from ..compression_utils import ZLibDecompressor
+from ..helpers import _EXC_SENTINEL, set_exception
+from ..streams import EofStream
+from .helpers import UNPACK_CLOSE_CODE, UNPACK_LEN3, websocket_mask
+from .models import (
+    WS_DEFLATE_TRAILING,
+    WebSocketError,
+    WSCloseCode,
+    WSMessage,
+    WSMsgType,
+)
+
+ALLOWED_CLOSE_CODES: Final[Set[int]] = {int(i) for i in WSCloseCode}
+
+# States for the reader, used to parse the WebSocket frame
+# integer values are used so they can be cythonized
+READ_HEADER = 1
+READ_PAYLOAD_LENGTH = 2
+READ_PAYLOAD_MASK = 3
+READ_PAYLOAD = 4
+
+WS_MSG_TYPE_BINARY = WSMsgType.BINARY
+WS_MSG_TYPE_TEXT = WSMsgType.TEXT
+
+# WSMsgType values unpacked so they can by cythonized to ints
+OP_CODE_NOT_SET = -1
+OP_CODE_CONTINUATION = WSMsgType.CONTINUATION.value
+OP_CODE_TEXT = WSMsgType.TEXT.value
+OP_CODE_BINARY = WSMsgType.BINARY.value
+OP_CODE_CLOSE = WSMsgType.CLOSE.value
+OP_CODE_PING = WSMsgType.PING.value
+OP_CODE_PONG = WSMsgType.PONG.value
+
+EMPTY_FRAME_ERROR = (True, b"")
+EMPTY_FRAME = (False, b"")
+
+COMPRESSED_NOT_SET = -1
+COMPRESSED_FALSE = 0
+COMPRESSED_TRUE = 1
+
+TUPLE_NEW = tuple.__new__
+
+cython_int = int  # Typed to int in Python, but cython with use a signed int in the pxd
+
+
+class WebSocketDataQueue:
+    """WebSocketDataQueue resumes and pauses an underlying stream.
+
+    It is a destination for WebSocket data.
+    """
+
+    def __init__(
+        self, protocol: BaseProtocol, limit: int, *, loop: asyncio.AbstractEventLoop
+    ) -> None:
+        self._size = 0
+        self._protocol = protocol
+        self._limit = limit * 2
+        self._loop = loop
+        self._eof = False
+        self._waiter: Optional[asyncio.Future[None]] = None
+        self._exception: Union[BaseException, None] = None
+        self._buffer: Deque[Tuple[WSMessage, int]] = deque()
+        self._get_buffer = self._buffer.popleft
+        self._put_buffer = self._buffer.append
+
+    def is_eof(self) -> bool:
+        return self._eof
+
+    def exception(self) -> Optional[BaseException]:
+        return self._exception
+
+    def set_exception(
+        self,
+        exc: BaseException,
+        exc_cause: builtins.BaseException = _EXC_SENTINEL,
+    ) -> None:
+        self._eof = True
+        self._exception = exc
+        if (waiter := self._waiter) is not None:
+            self._waiter = None
+            set_exception(waiter, exc, exc_cause)
+
+    def _release_waiter(self) -> None:
+        if (waiter := self._waiter) is None:
+            return
+        self._waiter = None
+        if not waiter.done():
+            waiter.set_result(None)
+
+    def feed_eof(self) -> None:
+        self._eof = True
+        self._release_waiter()
+        self._exception = None  # Break cyclic references
+
+    def feed_data(self, data: "WSMessage", size: "cython_int") -> None:
+        self._size += size
+        self._put_buffer((data, size))
+        self._release_waiter()
+        if self._size > self._limit and not self._protocol._reading_paused:
+            self._protocol.pause_reading()
+
+    async def read(self) -> WSMessage:
+        if not self._buffer and not self._eof:
+            assert not self._waiter
+            self._waiter = self._loop.create_future()
+            try:
+                await self._waiter
+            except (asyncio.CancelledError, asyncio.TimeoutError):
+                self._waiter = None
+                raise
+        return self._read_from_buffer()
+
+    def _read_from_buffer(self) -> WSMessage:
+        if self._buffer:
+            data, size = self._get_buffer()
+            self._size -= size
+            if self._size < self._limit and self._protocol._reading_paused:
+                self._protocol.resume_reading()
+            return data
+        if self._exception is not None:
+            raise self._exception
+        raise EofStream
+
+
+class WebSocketReader:
+    def __init__(
+        self, queue: WebSocketDataQueue, max_msg_size: int, compress: bool = True
+    ) -> None:
+        self.queue = queue
+        self._max_msg_size = max_msg_size
+
+        self._exc: Optional[Exception] = None
+        self._partial = bytearray()
+        self._state = READ_HEADER
+
+        self._opcode: int = OP_CODE_NOT_SET
+        self._frame_fin = False
+        self._frame_opcode: int = OP_CODE_NOT_SET
+        self._payload_fragments: list[bytes] = []
+        self._frame_payload_len = 0
+
+        self._tail: bytes = b""
+        self._has_mask = False
+        self._frame_mask: Optional[bytes] = None
+        self._payload_bytes_to_read = 0
+        self._payload_len_flag = 0
+        self._compressed: int = COMPRESSED_NOT_SET
+        self._decompressobj: Optional[ZLibDecompressor] = None
+        self._compress = compress
+
+    def feed_eof(self) -> None:
+        self.queue.feed_eof()
+
+    # data can be bytearray on Windows because proactor event loop uses bytearray
+    # and asyncio types this to Union[bytes, bytearray, memoryview] so we need
+    # coerce data to bytes if it is not
+    def feed_data(
+        self, data: Union[bytes, bytearray, memoryview]
+    ) -> Tuple[bool, bytes]:
+        if type(data) is not bytes:
+            data = bytes(data)
+
+        if self._exc is not None:
+            return True, data
+
+        try:
+            self._feed_data(data)
+        except Exception as exc:
+            self._exc = exc
+            set_exception(self.queue, exc)
+            return EMPTY_FRAME_ERROR
+
+        return EMPTY_FRAME
+
+    def _handle_frame(
+        self,
+        fin: bool,
+        opcode: Union[int, cython_int],  # Union intended: Cython pxd uses C int
+        payload: Union[bytes, bytearray],
+        compressed: Union[int, cython_int],  # Union intended: Cython pxd uses C int
+    ) -> None:
+        msg: WSMessage
+        if opcode in {OP_CODE_TEXT, OP_CODE_BINARY, OP_CODE_CONTINUATION}:
+            # load text/binary
+            if not fin:
+                # got partial frame payload
+                if opcode != OP_CODE_CONTINUATION:
+                    self._opcode = opcode
+                self._partial += payload
+                if self._max_msg_size and len(self._partial) >= self._max_msg_size:
+                    raise WebSocketError(
+                        WSCloseCode.MESSAGE_TOO_BIG,
+                        f"Message size {len(self._partial)} "
+                        f"exceeds limit {self._max_msg_size}",
+                    )
+                return
+
+            has_partial = bool(self._partial)
+            if opcode == OP_CODE_CONTINUATION:
+                if self._opcode == OP_CODE_NOT_SET:
+                    raise WebSocketError(
+                        WSCloseCode.PROTOCOL_ERROR,
+                        "Continuation frame for non started message",
+                    )
+                opcode = self._opcode
+                self._opcode = OP_CODE_NOT_SET
+            # previous frame was non finished
+            # we should get continuation opcode
+            elif has_partial:
+                raise WebSocketError(
+                    WSCloseCode.PROTOCOL_ERROR,
+                    "The opcode in non-fin frame is expected "
+                    f"to be zero, got {opcode!r}",
+                )
+
+            assembled_payload: Union[bytes, bytearray]
+            if has_partial:
+                assembled_payload = self._partial + payload
+                self._partial.clear()
+            else:
+                assembled_payload = payload
+
+            if self._max_msg_size and len(assembled_payload) >= self._max_msg_size:
+                raise WebSocketError(
+                    WSCloseCode.MESSAGE_TOO_BIG,
+                    f"Message size {len(assembled_payload)} "
+                    f"exceeds limit {self._max_msg_size}",
+                )
+
+            # Decompress process must to be done after all packets
+            # received.
+            if compressed:
+                if not self._decompressobj:
+                    self._decompressobj = ZLibDecompressor(suppress_deflate_header=True)
+                # XXX: It's possible that the zlib backend (isal is known to
+                # do this, maybe others too?) will return max_length bytes,
+                # but internally buffer more data such that the payload is
+                # >max_length, so we return one extra byte and if we're able
+                # to do that, then the message is too big.
+                payload_merged = self._decompressobj.decompress_sync(
+                    assembled_payload + WS_DEFLATE_TRAILING,
+                    (
+                        self._max_msg_size + 1
+                        if self._max_msg_size
+                        else self._max_msg_size
+                    ),
+                )
+                if self._max_msg_size and len(payload_merged) > self._max_msg_size:
+                    raise WebSocketError(
+                        WSCloseCode.MESSAGE_TOO_BIG,
+                        f"Decompressed message exceeds size limit {self._max_msg_size}",
+                    )
+            elif type(assembled_payload) is bytes:
+                payload_merged = assembled_payload
+            else:
+                payload_merged = bytes(assembled_payload)
+
+            if opcode == OP_CODE_TEXT:
+                try:
+                    text = payload_merged.decode("utf-8")
+                except UnicodeDecodeError as exc:
+                    raise WebSocketError(
+                        WSCloseCode.INVALID_TEXT, "Invalid UTF-8 text message"
+                    ) from exc
+
+                # XXX: The Text and Binary messages here can be a performance
+                # bottleneck, so we use tuple.__new__ to improve performance.
+                # This is not type safe, but many tests should fail in
+                # test_client_ws_functional.py if this is wrong.
+                self.queue.feed_data(
+                    TUPLE_NEW(WSMessage, (WS_MSG_TYPE_TEXT, text, "")),
+                    len(payload_merged),
+                )
+            else:
+                self.queue.feed_data(
+                    TUPLE_NEW(WSMessage, (WS_MSG_TYPE_BINARY, payload_merged, "")),
+                    len(payload_merged),
+                )
+        elif opcode == OP_CODE_CLOSE:
+            if len(payload) >= 2:
+                close_code = UNPACK_CLOSE_CODE(payload[:2])[0]
+                if close_code < 3000 and close_code not in ALLOWED_CLOSE_CODES:
+                    raise WebSocketError(
+                        WSCloseCode.PROTOCOL_ERROR,
+                        f"Invalid close code: {close_code}",
+                    )
+                try:
+                    close_message = payload[2:].decode("utf-8")
+                except UnicodeDecodeError as exc:
+                    raise WebSocketError(
+                        WSCloseCode.INVALID_TEXT, "Invalid UTF-8 text message"
+                    ) from exc
+                msg = TUPLE_NEW(WSMessage, (WSMsgType.CLOSE, close_code, close_message))
+            elif payload:
+                raise WebSocketError(
+                    WSCloseCode.PROTOCOL_ERROR,
+                    f"Invalid close frame: {fin} {opcode} {payload!r}",
+                )
+            else:
+                msg = TUPLE_NEW(WSMessage, (WSMsgType.CLOSE, 0, ""))
+
+            self.queue.feed_data(msg, 0)
+        elif opcode == OP_CODE_PING:
+            msg = TUPLE_NEW(WSMessage, (WSMsgType.PING, payload, ""))
+            self.queue.feed_data(msg, len(payload))
+        elif opcode == OP_CODE_PONG:
+            msg = TUPLE_NEW(WSMessage, (WSMsgType.PONG, payload, ""))
+            self.queue.feed_data(msg, len(payload))
+        else:
+            raise WebSocketError(
+                WSCloseCode.PROTOCOL_ERROR, f"Unexpected opcode={opcode!r}"
+            )
+
+    def _feed_data(self, data: bytes) -> None:
+        """Return the next frame from the socket."""
+        if self._tail:
+            data, self._tail = self._tail + data, b""
+
+        start_pos: int = 0
+        data_len = len(data)
+        data_cstr = data
+
+        while True:
+            # read header
+            if self._state == READ_HEADER:
+                if data_len - start_pos < 2:
+                    break
+                first_byte = data_cstr[start_pos]
+                second_byte = data_cstr[start_pos + 1]
+                start_pos += 2
+
+                fin = (first_byte >> 7) & 1
+                rsv1 = (first_byte >> 6) & 1
+                rsv2 = (first_byte >> 5) & 1
+                rsv3 = (first_byte >> 4) & 1
+                opcode = first_byte & 0xF
+
+                # frame-fin = %x0 ; more frames of this message follow
+                #           / %x1 ; final frame of this message
+                # frame-rsv1 = %x0 ;
+                #    1 bit, MUST be 0 unless negotiated otherwise
+                # frame-rsv2 = %x0 ;
+                #    1 bit, MUST be 0 unless negotiated otherwise
+                # frame-rsv3 = %x0 ;
+                #    1 bit, MUST be 0 unless negotiated otherwise
+                #
+                # Remove rsv1 from this test for deflate development
+                if rsv2 or rsv3 or (rsv1 and not self._compress):
+                    raise WebSocketError(
+                        WSCloseCode.PROTOCOL_ERROR,
+                        "Received frame with non-zero reserved bits",
+                    )
+
+                if opcode > 0x7 and fin == 0:
+                    raise WebSocketError(
+                        WSCloseCode.PROTOCOL_ERROR,
+                        "Received fragmented control frame",
+                    )
+
+                has_mask = (second_byte >> 7) & 1
+                length = second_byte & 0x7F
+
+                # Control frames MUST have a payload
+                # length of 125 bytes or less
+                if opcode > 0x7 and length > 125:
+                    raise WebSocketError(
+                        WSCloseCode.PROTOCOL_ERROR,
+                        "Control frame payload cannot be larger than 125 bytes",
+                    )
+
+                # Set compress status if last package is FIN
+                # OR set compress status if this is first fragment
+                # Raise error if not first fragment with rsv1 = 0x1
+                if self._frame_fin or self._compressed == COMPRESSED_NOT_SET:
+                    self._compressed = COMPRESSED_TRUE if rsv1 else COMPRESSED_FALSE
+                elif rsv1:
+                    raise WebSocketError(
+                        WSCloseCode.PROTOCOL_ERROR,
+                        "Received frame with non-zero reserved bits",
+                    )
+
+                self._frame_fin = bool(fin)
+                self._frame_opcode = opcode
+                self._has_mask = bool(has_mask)
+                self._payload_len_flag = length
+                self._state = READ_PAYLOAD_LENGTH
+
+            # read payload length
+            if self._state == READ_PAYLOAD_LENGTH:
+                len_flag = self._payload_len_flag
+                if len_flag == 126:
+                    if data_len - start_pos < 2:
+                        break
+                    first_byte = data_cstr[start_pos]
+                    second_byte = data_cstr[start_pos + 1]
+                    start_pos += 2
+                    self._payload_bytes_to_read = first_byte << 8 | second_byte
+                elif len_flag > 126:
+                    if data_len - start_pos < 8:
+                        break
+                    self._payload_bytes_to_read = UNPACK_LEN3(data, start_pos)[0]
+                    start_pos += 8
+                else:
+                    self._payload_bytes_to_read = len_flag
+
+                self._state = READ_PAYLOAD_MASK if self._has_mask else READ_PAYLOAD
+
+            # read payload mask
+            if self._state == READ_PAYLOAD_MASK:
+                if data_len - start_pos < 4:
+                    break
+                self._frame_mask = data_cstr[start_pos : start_pos + 4]
+                start_pos += 4
+                self._state = READ_PAYLOAD
+
+            if self._state == READ_PAYLOAD:
+                chunk_len = data_len - start_pos
+                if self._payload_bytes_to_read >= chunk_len:
+                    f_end_pos = data_len
+                    self._payload_bytes_to_read -= chunk_len
+                else:
+                    f_end_pos = start_pos + self._payload_bytes_to_read
+                    self._payload_bytes_to_read = 0
+
+                had_fragments = self._frame_payload_len
+                self._frame_payload_len += f_end_pos - start_pos
+                f_start_pos = start_pos
+                start_pos = f_end_pos
+
+                if self._payload_bytes_to_read != 0:
+                    # If we don't have a complete frame, we need to save the
+                    # data for the next call to feed_data.
+                    self._payload_fragments.append(data_cstr[f_start_pos:f_end_pos])
+                    break
+
+                payload: Union[bytes, bytearray]
+                if had_fragments:
+                    # We have to join the payload fragments get the payload
+                    self._payload_fragments.append(data_cstr[f_start_pos:f_end_pos])
+                    if self._has_mask:
+                        assert self._frame_mask is not None
+                        payload_bytearray = bytearray(b"".join(self._payload_fragments))
+                        websocket_mask(self._frame_mask, payload_bytearray)
+                        payload = payload_bytearray
+                    else:
+                        payload = b"".join(self._payload_fragments)
+                    self._payload_fragments.clear()
+                elif self._has_mask:
+                    assert self._frame_mask is not None
+                    payload_bytearray = data_cstr[f_start_pos:f_end_pos]  # type: ignore[assignment]
+                    if type(payload_bytearray) is not bytearray:  # pragma: no branch
+                        # Cython will do the conversion for us
+                        # but we need to do it for Python and we
+                        # will always get here in Python
+                        payload_bytearray = bytearray(payload_bytearray)
+                    websocket_mask(self._frame_mask, payload_bytearray)
+                    payload = payload_bytearray
+                else:
+                    payload = data_cstr[f_start_pos:f_end_pos]
+
+                self._handle_frame(
+                    self._frame_fin, self._frame_opcode, payload, self._compressed
+                )
+                self._frame_payload_len = 0
+                self._state = READ_HEADER
+
+        # XXX: Cython needs slices to be bounded, so we can't omit the slice end here.
+        self._tail = data_cstr[start_pos:data_len] if start_pos < data_len else b""

backend_service/venv/lib/python3.13/site-packages/aiohttp/_websocket/reader_py.py

@@ -0,0 +1,476 @@
+"""Reader for WebSocket protocol versions 13 and 8."""
+
+import asyncio
+import builtins
+from collections import deque
+from typing import Deque, Final, Optional, Set, Tuple, Union
+
+from ..base_protocol import BaseProtocol
+from ..compression_utils import ZLibDecompressor
+from ..helpers import _EXC_SENTINEL, set_exception
+from ..streams import EofStream
+from .helpers import UNPACK_CLOSE_CODE, UNPACK_LEN3, websocket_mask
+from .models import (
+    WS_DEFLATE_TRAILING,
+    WebSocketError,
+    WSCloseCode,
+    WSMessage,
+    WSMsgType,
+)
+
+ALLOWED_CLOSE_CODES: Final[Set[int]] = {int(i) for i in WSCloseCode}
+
+# States for the reader, used to parse the WebSocket frame
+# integer values are used so they can be cythonized
+READ_HEADER = 1
+READ_PAYLOAD_LENGTH = 2
+READ_PAYLOAD_MASK = 3
+READ_PAYLOAD = 4
+
+WS_MSG_TYPE_BINARY = WSMsgType.BINARY
+WS_MSG_TYPE_TEXT = WSMsgType.TEXT
+
+# WSMsgType values unpacked so they can by cythonized to ints
+OP_CODE_NOT_SET = -1
+OP_CODE_CONTINUATION = WSMsgType.CONTINUATION.value
+OP_CODE_TEXT = WSMsgType.TEXT.value
+OP_CODE_BINARY = WSMsgType.BINARY.value
+OP_CODE_CLOSE = WSMsgType.CLOSE.value
+OP_CODE_PING = WSMsgType.PING.value
+OP_CODE_PONG = WSMsgType.PONG.value
+
+EMPTY_FRAME_ERROR = (True, b"")
+EMPTY_FRAME = (False, b"")
+
+COMPRESSED_NOT_SET = -1
+COMPRESSED_FALSE = 0
+COMPRESSED_TRUE = 1
+
+TUPLE_NEW = tuple.__new__
+
+cython_int = int  # Typed to int in Python, but cython with use a signed int in the pxd
+
+
+class WebSocketDataQueue:
+    """WebSocketDataQueue resumes and pauses an underlying stream.
+
+    It is a destination for WebSocket data.
+    """
+
+    def __init__(
+        self, protocol: BaseProtocol, limit: int, *, loop: asyncio.AbstractEventLoop
+    ) -> None:
+        self._size = 0
+        self._protocol = protocol
+        self._limit = limit * 2
+        self._loop = loop
+        self._eof = False
+        self._waiter: Optional[asyncio.Future[None]] = None
+        self._exception: Union[BaseException, None] = None
+        self._buffer: Deque[Tuple[WSMessage, int]] = deque()
+        self._get_buffer = self._buffer.popleft
+        self._put_buffer = self._buffer.append
+
+    def is_eof(self) -> bool:
+        return self._eof
+
+    def exception(self) -> Optional[BaseException]:
+        return self._exception
+
+    def set_exception(
+        self,
+        exc: BaseException,
+        exc_cause: builtins.BaseException = _EXC_SENTINEL,
+    ) -> None:
+        self._eof = True
+        self._exception = exc
+        if (waiter := self._waiter) is not None:
+            self._waiter = None
+            set_exception(waiter, exc, exc_cause)
+
+    def _release_waiter(self) -> None:
+        if (waiter := self._waiter) is None:
+            return
+        self._waiter = None
+        if not waiter.done():
+            waiter.set_result(None)
+
+    def feed_eof(self) -> None:
+        self._eof = True
+        self._release_waiter()
+        self._exception = None  # Break cyclic references
+
+    def feed_data(self, data: "WSMessage", size: "cython_int") -> None:
+        self._size += size
+        self._put_buffer((data, size))
+        self._release_waiter()
+        if self._size > self._limit and not self._protocol._reading_paused:
+            self._protocol.pause_reading()
+
+    async def read(self) -> WSMessage:
+        if not self._buffer and not self._eof:
+            assert not self._waiter
+            self._waiter = self._loop.create_future()
+            try:
+                await self._waiter
+            except (asyncio.CancelledError, asyncio.TimeoutError):
+                self._waiter = None
+                raise
+        return self._read_from_buffer()
+
+    def _read_from_buffer(self) -> WSMessage:
+        if self._buffer:
+            data, size = self._get_buffer()
+            self._size -= size
+            if self._size < self._limit and self._protocol._reading_paused:
+                self._protocol.resume_reading()
+            return data
+        if self._exception is not None:
+            raise self._exception
+        raise EofStream
+
+
+class WebSocketReader:
+    def __init__(
+        self, queue: WebSocketDataQueue, max_msg_size: int, compress: bool = True
+    ) -> None:
+        self.queue = queue
+        self._max_msg_size = max_msg_size
+
+        self._exc: Optional[Exception] = None
+        self._partial = bytearray()
+        self._state = READ_HEADER
+
+        self._opcode: int = OP_CODE_NOT_SET
+        self._frame_fin = False
+        self._frame_opcode: int = OP_CODE_NOT_SET
+        self._payload_fragments: list[bytes] = []
+        self._frame_payload_len = 0
+
+        self._tail: bytes = b""
+        self._has_mask = False
+        self._frame_mask: Optional[bytes] = None
+        self._payload_bytes_to_read = 0
+        self._payload_len_flag = 0
+        self._compressed: int = COMPRESSED_NOT_SET
+        self._decompressobj: Optional[ZLibDecompressor] = None
+        self._compress = compress
+
+    def feed_eof(self) -> None:
+        self.queue.feed_eof()
+
+    # data can be bytearray on Windows because proactor event loop uses bytearray
+    # and asyncio types this to Union[bytes, bytearray, memoryview] so we need
+    # coerce data to bytes if it is not
+    def feed_data(
+        self, data: Union[bytes, bytearray, memoryview]
+    ) -> Tuple[bool, bytes]:
+        if type(data) is not bytes:
+            data = bytes(data)
+
+        if self._exc is not None:
+            return True, data
+
+        try:
+            self._feed_data(data)
+        except Exception as exc:
+            self._exc = exc
+            set_exception(self.queue, exc)
+            return EMPTY_FRAME_ERROR
+
+        return EMPTY_FRAME
+
+    def _handle_frame(
+        self,
+        fin: bool,
+        opcode: Union[int, cython_int],  # Union intended: Cython pxd uses C int
+        payload: Union[bytes, bytearray],
+        compressed: Union[int, cython_int],  # Union intended: Cython pxd uses C int
+    ) -> None:
+        msg: WSMessage
+        if opcode in {OP_CODE_TEXT, OP_CODE_BINARY, OP_CODE_CONTINUATION}:
+            # load text/binary
+            if not fin:
+                # got partial frame payload
+                if opcode != OP_CODE_CONTINUATION:
+                    self._opcode = opcode
+                self._partial += payload
+                if self._max_msg_size and len(self._partial) >= self._max_msg_size:
+                    raise WebSocketError(
+                        WSCloseCode.MESSAGE_TOO_BIG,
+                        f"Message size {len(self._partial)} "
+                        f"exceeds limit {self._max_msg_size}",
+                    )
+                return
+
+            has_partial = bool(self._partial)
+            if opcode == OP_CODE_CONTINUATION:
+                if self._opcode == OP_CODE_NOT_SET:
+                    raise WebSocketError(
+                        WSCloseCode.PROTOCOL_ERROR,
+                        "Continuation frame for non started message",
+                    )
+                opcode = self._opcode
+                self._opcode = OP_CODE_NOT_SET
+            # previous frame was non finished
+            # we should get continuation opcode
+            elif has_partial:
+                raise WebSocketError(
+                    WSCloseCode.PROTOCOL_ERROR,
+                    "The opcode in non-fin frame is expected "
+                    f"to be zero, got {opcode!r}",
+                )
+
+            assembled_payload: Union[bytes, bytearray]
+            if has_partial:
+                assembled_payload = self._partial + payload
+                self._partial.clear()
+            else:
+                assembled_payload = payload
+
+            if self._max_msg_size and len(assembled_payload) >= self._max_msg_size:
+                raise WebSocketError(
+                    WSCloseCode.MESSAGE_TOO_BIG,
+                    f"Message size {len(assembled_payload)} "
+                    f"exceeds limit {self._max_msg_size}",
+                )
+
+            # Decompress process must to be done after all packets
+            # received.
+            if compressed:
+                if not self._decompressobj:
+                    self._decompressobj = ZLibDecompressor(suppress_deflate_header=True)
+                # XXX: It's possible that the zlib backend (isal is known to
+                # do this, maybe others too?) will return max_length bytes,
+                # but internally buffer more data such that the payload is
+                # >max_length, so we return one extra byte and if we're able
+                # to do that, then the message is too big.
+                payload_merged = self._decompressobj.decompress_sync(
+                    assembled_payload + WS_DEFLATE_TRAILING,
+                    (
+                        self._max_msg_size + 1
+                        if self._max_msg_size
+                        else self._max_msg_size
+                    ),
+                )
+                if self._max_msg_size and len(payload_merged) > self._max_msg_size:
+                    raise WebSocketError(
+                        WSCloseCode.MESSAGE_TOO_BIG,
+                        f"Decompressed message exceeds size limit {self._max_msg_size}",
+                    )
+            elif type(assembled_payload) is bytes:
+                payload_merged = assembled_payload
+            else:
+                payload_merged = bytes(assembled_payload)
+
+            if opcode == OP_CODE_TEXT:
+                try:
+                    text = payload_merged.decode("utf-8")
+                except UnicodeDecodeError as exc:
+                    raise WebSocketError(
+                        WSCloseCode.INVALID_TEXT, "Invalid UTF-8 text message"
+                    ) from exc
+
+                # XXX: The Text and Binary messages here can be a performance
+                # bottleneck, so we use tuple.__new__ to improve performance.
+                # This is not type safe, but many tests should fail in
+                # test_client_ws_functional.py if this is wrong.
+                self.queue.feed_data(
+                    TUPLE_NEW(WSMessage, (WS_MSG_TYPE_TEXT, text, "")),
+                    len(payload_merged),
+                )
+            else:
+                self.queue.feed_data(
+                    TUPLE_NEW(WSMessage, (WS_MSG_TYPE_BINARY, payload_merged, "")),
+                    len(payload_merged),
+                )
+        elif opcode == OP_CODE_CLOSE:
+            if len(payload) >= 2:
+                close_code = UNPACK_CLOSE_CODE(payload[:2])[0]
+                if close_code < 3000 and close_code not in ALLOWED_CLOSE_CODES:
+                    raise WebSocketError(
+                        WSCloseCode.PROTOCOL_ERROR,
+                        f"Invalid close code: {close_code}",
+                    )
+                try:
+                    close_message = payload[2:].decode("utf-8")
+                except UnicodeDecodeError as exc:
+                    raise WebSocketError(
+                        WSCloseCode.INVALID_TEXT, "Invalid UTF-8 text message"
+                    ) from exc
+                msg = TUPLE_NEW(WSMessage, (WSMsgType.CLOSE, close_code, close_message))
+            elif payload:
+                raise WebSocketError(
+                    WSCloseCode.PROTOCOL_ERROR,
+                    f"Invalid close frame: {fin} {opcode} {payload!r}",
+                )
+            else:
+                msg = TUPLE_NEW(WSMessage, (WSMsgType.CLOSE, 0, ""))
+
+            self.queue.feed_data(msg, 0)
+        elif opcode == OP_CODE_PING:
+            msg = TUPLE_NEW(WSMessage, (WSMsgType.PING, payload, ""))
+            self.queue.feed_data(msg, len(payload))
+        elif opcode == OP_CODE_PONG:
+            msg = TUPLE_NEW(WSMessage, (WSMsgType.PONG, payload, ""))
+            self.queue.feed_data(msg, len(payload))
+        else:
+            raise WebSocketError(
+                WSCloseCode.PROTOCOL_ERROR, f"Unexpected opcode={opcode!r}"
+            )
+
+    def _feed_data(self, data: bytes) -> None:
+        """Return the next frame from the socket."""
+        if self._tail:
+            data, self._tail = self._tail + data, b""
+
+        start_pos: int = 0
+        data_len = len(data)
+        data_cstr = data
+
+        while True:
+            # read header
+            if self._state == READ_HEADER:
+                if data_len - start_pos < 2:
+                    break
+                first_byte = data_cstr[start_pos]
+                second_byte = data_cstr[start_pos + 1]
+                start_pos += 2
+
+                fin = (first_byte >> 7) & 1
+                rsv1 = (first_byte >> 6) & 1
+                rsv2 = (first_byte >> 5) & 1
+                rsv3 = (first_byte >> 4) & 1
+                opcode = first_byte & 0xF
+
+                # frame-fin = %x0 ; more frames of this message follow
+                #           / %x1 ; final frame of this message
+                # frame-rsv1 = %x0 ;
+                #    1 bit, MUST be 0 unless negotiated otherwise
+                # frame-rsv2 = %x0 ;
+                #    1 bit, MUST be 0 unless negotiated otherwise
+                # frame-rsv3 = %x0 ;
+                #    1 bit, MUST be 0 unless negotiated otherwise
+                #
+                # Remove rsv1 from this test for deflate development
+                if rsv2 or rsv3 or (rsv1 and not self._compress):
+                    raise WebSocketError(
+                        WSCloseCode.PROTOCOL_ERROR,
+                        "Received frame with non-zero reserved bits",
+                    )
+
+                if opcode > 0x7 and fin == 0:
+                    raise WebSocketError(
+                        WSCloseCode.PROTOCOL_ERROR,
+                        "Received fragmented control frame",
+                    )
+
+                has_mask = (second_byte >> 7) & 1
+                length = second_byte & 0x7F
+
+                # Control frames MUST have a payload
+                # length of 125 bytes or less
+                if opcode > 0x7 and length > 125:
+                    raise WebSocketError(
+                        WSCloseCode.PROTOCOL_ERROR,
+                        "Control frame payload cannot be larger than 125 bytes",
+                    )
+
+                # Set compress status if last package is FIN
+                # OR set compress status if this is first fragment
+                # Raise error if not first fragment with rsv1 = 0x1
+                if self._frame_fin or self._compressed == COMPRESSED_NOT_SET:
+                    self._compressed = COMPRESSED_TRUE if rsv1 else COMPRESSED_FALSE
+                elif rsv1:
+                    raise WebSocketError(
+                        WSCloseCode.PROTOCOL_ERROR,
+                        "Received frame with non-zero reserved bits",
+                    )
+
+                self._frame_fin = bool(fin)
+                self._frame_opcode = opcode
+                self._has_mask = bool(has_mask)
+                self._payload_len_flag = length
+                self._state = READ_PAYLOAD_LENGTH
+
+            # read payload length
+            if self._state == READ_PAYLOAD_LENGTH:
+                len_flag = self._payload_len_flag
+                if len_flag == 126:
+                    if data_len - start_pos < 2:
+                        break
+                    first_byte = data_cstr[start_pos]
+                    second_byte = data_cstr[start_pos + 1]
+                    start_pos += 2
+                    self._payload_bytes_to_read = first_byte << 8 | second_byte
+                elif len_flag > 126:
+                    if data_len - start_pos < 8:
+                        break
+                    self._payload_bytes_to_read = UNPACK_LEN3(data, start_pos)[0]
+                    start_pos += 8
+                else:
+                    self._payload_bytes_to_read = len_flag
+
+                self._state = READ_PAYLOAD_MASK if self._has_mask else READ_PAYLOAD
+
+            # read payload mask
+            if self._state == READ_PAYLOAD_MASK:
+                if data_len - start_pos < 4:
+                    break
+                self._frame_mask = data_cstr[start_pos : start_pos + 4]
+                start_pos += 4
+                self._state = READ_PAYLOAD
+
+            if self._state == READ_PAYLOAD:
+                chunk_len = data_len - start_pos
+                if self._payload_bytes_to_read >= chunk_len:
+                    f_end_pos = data_len
+                    self._payload_bytes_to_read -= chunk_len
+                else:
+                    f_end_pos = start_pos + self._payload_bytes_to_read
+                    self._payload_bytes_to_read = 0
+
+                had_fragments = self._frame_payload_len
+                self._frame_payload_len += f_end_pos - start_pos
+                f_start_pos = start_pos
+                start_pos = f_end_pos
+
+                if self._payload_bytes_to_read != 0:
+                    # If we don't have a complete frame, we need to save the
+                    # data for the next call to feed_data.
+                    self._payload_fragments.append(data_cstr[f_start_pos:f_end_pos])
+                    break
+
+                payload: Union[bytes, bytearray]
+                if had_fragments:
+                    # We have to join the payload fragments get the payload
+                    self._payload_fragments.append(data_cstr[f_start_pos:f_end_pos])
+                    if self._has_mask:
+                        assert self._frame_mask is not None
+                        payload_bytearray = bytearray(b"".join(self._payload_fragments))
+                        websocket_mask(self._frame_mask, payload_bytearray)
+                        payload = payload_bytearray
+                    else:
+                        payload = b"".join(self._payload_fragments)
+                    self._payload_fragments.clear()
+                elif self._has_mask:
+                    assert self._frame_mask is not None
+                    payload_bytearray = data_cstr[f_start_pos:f_end_pos]  # type: ignore[assignment]
+                    if type(payload_bytearray) is not bytearray:  # pragma: no branch
+                        # Cython will do the conversion for us
+                        # but we need to do it for Python and we
+                        # will always get here in Python
+                        payload_bytearray = bytearray(payload_bytearray)
+                    websocket_mask(self._frame_mask, payload_bytearray)
+                    payload = payload_bytearray
+                else:
+                    payload = data_cstr[f_start_pos:f_end_pos]
+
+                self._handle_frame(
+                    self._frame_fin, self._frame_opcode, payload, self._compressed
+                )
+                self._frame_payload_len = 0
+                self._state = READ_HEADER
+
+        # XXX: Cython needs slices to be bounded, so we can't omit the slice end here.
+        self._tail = data_cstr[start_pos:data_len] if start_pos < data_len else b""

backend_service/venv/lib/python3.13/site-packages/aiohttp/_websocket/writer.py

@@ -0,0 +1,262 @@
+"""WebSocket protocol versions 13 and 8."""
+
+import asyncio
+import random
+import sys
+from functools import partial
+from typing import Final, Optional, Set, Union
+
+from ..base_protocol import BaseProtocol
+from ..client_exceptions import ClientConnectionResetError
+from ..compression_utils import ZLibBackend, ZLibCompressor
+from .helpers import (
+    MASK_LEN,
+    MSG_SIZE,
+    PACK_CLOSE_CODE,
+    PACK_LEN1,
+    PACK_LEN2,
+    PACK_LEN3,
+    PACK_RANDBITS,
+    websocket_mask,
+)
+from .models import WS_DEFLATE_TRAILING, WSMsgType
+
+DEFAULT_LIMIT: Final[int] = 2**16
+
+# WebSocket opcode boundary: opcodes 0-7 are data frames, 8-15 are control frames
+# Control frames (ping, pong, close) are never compressed
+WS_CONTROL_FRAME_OPCODE: Final[int] = 8
+
+# For websockets, keeping latency low is extremely important as implementations
+# generally expect to be able to send and receive messages quickly. We use a
+# larger chunk size to reduce the number of executor calls and avoid task
+# creation overhead, since both are significant sources of latency when chunks
+# are small. A size of 16KiB was chosen as a balance between avoiding task
+# overhead and not blocking the event loop too long with synchronous compression.
+
+WEBSOCKET_MAX_SYNC_CHUNK_SIZE = 16 * 1024
+
+
+class WebSocketWriter:
+    """WebSocket writer.
+
+    The writer is responsible for sending messages to the client. It is
+    created by the protocol when a connection is established. The writer
+    should avoid implementing any application logic and should only be
+    concerned with the low-level details of the WebSocket protocol.
+    """
+
+    def __init__(
+        self,
+        protocol: BaseProtocol,
+        transport: asyncio.Transport,
+        *,
+        use_mask: bool = False,
+        limit: int = DEFAULT_LIMIT,
+        random: random.Random = random.Random(),
+        compress: int = 0,
+        notakeover: bool = False,
+    ) -> None:
+        """Initialize a WebSocket writer."""
+        self.protocol = protocol
+        self.transport = transport
+        self.use_mask = use_mask
+        self.get_random_bits = partial(random.getrandbits, 32)
+        self.compress = compress
+        self.notakeover = notakeover
+        self._closing = False
+        self._limit = limit
+        self._output_size = 0
+        self._compressobj: Optional[ZLibCompressor] = None
+        self._send_lock = asyncio.Lock()
+        self._background_tasks: Set[asyncio.Task[None]] = set()
+
+    async def send_frame(
+        self, message: bytes, opcode: int, compress: Optional[int] = None
+    ) -> None:
+        """Send a frame over the websocket with message as its payload."""
+        if self._closing and not (opcode & WSMsgType.CLOSE):
+            raise ClientConnectionResetError("Cannot write to closing transport")
+
+        if not (compress or self.compress) or opcode >= WS_CONTROL_FRAME_OPCODE:
+            # Non-compressed frames don't need lock or shield
+            self._write_websocket_frame(message, opcode, 0)
+        elif len(message) <= WEBSOCKET_MAX_SYNC_CHUNK_SIZE:
+            # Small compressed payloads - compress synchronously in event loop
+            # We need the lock even though sync compression has no await points.
+            # This prevents small frames from interleaving with large frames that
+            # compress in the executor, avoiding compressor state corruption.
+            async with self._send_lock:
+                self._send_compressed_frame_sync(message, opcode, compress)
+        else:
+            # Large compressed frames need shield to prevent corruption
+            # For large compressed frames, the entire compress+send
+            # operation must be atomic. If cancelled after compression but
+            # before send, the compressor state would be advanced but data
+            # not sent, corrupting subsequent frames.
+            # Create a task to shield from cancellation
+            # The lock is acquired inside the shielded task so the entire
+            # operation (lock + compress + send) completes atomically.
+            # Use eager_start on Python 3.12+ to avoid scheduling overhead
+            loop = asyncio.get_running_loop()
+            coro = self._send_compressed_frame_async_locked(message, opcode, compress)
+            if sys.version_info >= (3, 12):
+                send_task = asyncio.Task(coro, loop=loop, eager_start=True)
+            else:
+                send_task = loop.create_task(coro)
+            # Keep a strong reference to prevent garbage collection
+            self._background_tasks.add(send_task)
+            send_task.add_done_callback(self._background_tasks.discard)
+            await asyncio.shield(send_task)
+
+        # It is safe to return control to the event loop when using compression
+        # after this point as we have already sent or buffered all the data.
+        # Once we have written output_size up to the limit, we call the
+        # drain helper which waits for the transport to be ready to accept
+        # more data. This is a flow control mechanism to prevent the buffer
+        # from growing too large. The drain helper will return right away
+        # if the writer is not paused.
+        if self._output_size > self._limit:
+            self._output_size = 0
+            if self.protocol._paused:
+                await self.protocol._drain_helper()
+
+    def _write_websocket_frame(self, message: bytes, opcode: int, rsv: int) -> None:
+        """
+        Write a websocket frame to the transport.
+
+        This method handles frame header construction, masking, and writing to transport.
+        It does not handle compression or flow control - those are the responsibility
+        of the caller.
+        """
+        msg_length = len(message)
+
+        use_mask = self.use_mask
+        mask_bit = 0x80 if use_mask else 0
+
+        # Depending on the message length, the header is assembled differently.
+        # The first byte is reserved for the opcode and the RSV bits.
+        first_byte = 0x80 | rsv | opcode
+        if msg_length < 126:
+            header = PACK_LEN1(first_byte, msg_length | mask_bit)
+            header_len = 2
+        elif msg_length < 65536:
+            header = PACK_LEN2(first_byte, 126 | mask_bit, msg_length)
+            header_len = 4
+        else:
+            header = PACK_LEN3(first_byte, 127 | mask_bit, msg_length)
+            header_len = 10
+
+        if self.transport.is_closing():
+            raise ClientConnectionResetError("Cannot write to closing transport")
+
+        # https://datatracker.ietf.org/doc/html/rfc6455#section-5.3
+        # If we are using a mask, we need to generate it randomly
+        # and apply it to the message before sending it. A mask is
+        # a 32-bit value that is applied to the message using a
+        # bitwise XOR operation. It is used to prevent certain types
+        # of attacks on the websocket protocol. The mask is only used
+        # when aiohttp is acting as a client. Servers do not use a mask.
+        if use_mask:
+            mask = PACK_RANDBITS(self.get_random_bits())
+            message = bytearray(message)
+            websocket_mask(mask, message)
+            self.transport.write(header + mask + message)
+            self._output_size += MASK_LEN
+        elif msg_length > MSG_SIZE:
+            self.transport.write(header)
+            self.transport.write(message)
+        else:
+            self.transport.write(header + message)
+
+        self._output_size += header_len + msg_length
+
+    def _get_compressor(self, compress: Optional[int]) -> ZLibCompressor:
+        """Get or create a compressor object for the given compression level."""
+        if compress:
+            # Do not set self._compress if compressing is for this frame
+            return ZLibCompressor(
+                level=ZLibBackend.Z_BEST_SPEED,
+                wbits=-compress,
+                max_sync_chunk_size=WEBSOCKET_MAX_SYNC_CHUNK_SIZE,
+            )
+        if not self._compressobj:
+            self._compressobj = ZLibCompressor(
+                level=ZLibBackend.Z_BEST_SPEED,
+                wbits=-self.compress,
+                max_sync_chunk_size=WEBSOCKET_MAX_SYNC_CHUNK_SIZE,
+            )
+        return self._compressobj
+
+    def _send_compressed_frame_sync(
+        self, message: bytes, opcode: int, compress: Optional[int]
+    ) -> None:
+        """
+        Synchronous send for small compressed frames.
+
+        This is used for small compressed payloads that compress synchronously in the event loop.
+        Since there are no await points, this is inherently cancellation-safe.
+        """
+        # RSV are the reserved bits in the frame header. They are used to
+        # indicate that the frame is using an extension.
+        # https://datatracker.ietf.org/doc/html/rfc6455#section-5.2
+        compressobj = self._get_compressor(compress)
+        # (0x40) RSV1 is set for compressed frames
+        # https://datatracker.ietf.org/doc/html/rfc7692#section-7.2.3.1
+        self._write_websocket_frame(
+            (
+                compressobj.compress_sync(message)
+                + compressobj.flush(
+                    ZLibBackend.Z_FULL_FLUSH
+                    if self.notakeover
+                    else ZLibBackend.Z_SYNC_FLUSH
+                )
+            ).removesuffix(WS_DEFLATE_TRAILING),
+            opcode,
+            0x40,
+        )
+
+    async def _send_compressed_frame_async_locked(
+        self, message: bytes, opcode: int, compress: Optional[int]
+    ) -> None:
+        """
+        Async send for large compressed frames with lock.
+
+        Acquires the lock and compresses large payloads asynchronously in
+        the executor. The lock is held for the entire operation to ensure
+        the compressor state is not corrupted by concurrent sends.
+
+        MUST be run shielded from cancellation. If cancelled after
+        compression but before sending, the compressor state would be
+        advanced but data not sent, corrupting subsequent frames.
+        """
+        async with self._send_lock:
+            # RSV are the reserved bits in the frame header. They are used to
+            # indicate that the frame is using an extension.
+            # https://datatracker.ietf.org/doc/html/rfc6455#section-5.2
+            compressobj = self._get_compressor(compress)
+            # (0x40) RSV1 is set for compressed frames
+            # https://datatracker.ietf.org/doc/html/rfc7692#section-7.2.3.1
+            self._write_websocket_frame(
+                (
+                    await compressobj.compress(message)
+                    + compressobj.flush(
+                        ZLibBackend.Z_FULL_FLUSH
+                        if self.notakeover
+                        else ZLibBackend.Z_SYNC_FLUSH
+                    )
+                ).removesuffix(WS_DEFLATE_TRAILING),
+                opcode,
+                0x40,
+            )
+
+    async def close(self, code: int = 1000, message: Union[bytes, str] = b"") -> None:
+        """Close the websocket, sending the specified code and message."""
+        if isinstance(message, str):
+            message = message.encode("utf-8")
+        try:
+            await self.send_frame(
+                PACK_CLOSE_CODE(code) + message, opcode=WSMsgType.CLOSE
+            )
+        finally:
+            self._closing = True