models.py•2.12 kB
"""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."""