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"""WebSocket client for asyncio."""
import asyncio
from typing import Any, Optional, cast
import async_timeout
from .client_exceptions import ClientError
from .client_reqrep import ClientResponse
from .helpers import call_later, set_result
from .http import (
WS_CLOSED_MESSAGE,
WS_CLOSING_MESSAGE,
WebSocketError,
WSCloseCode,
WSMessage,
WSMsgType,
)
from .http_websocket import WebSocketWriter # WSMessage
from .streams import EofStream, FlowControlDataQueue
from .typedefs import (
DEFAULT_JSON_DECODER,
DEFAULT_JSON_ENCODER,
JSONDecoder,
JSONEncoder,
)
class ClientWebSocketResponse:
def __init__(
self,
reader: "FlowControlDataQueue[WSMessage]",
writer: WebSocketWriter,
protocol: Optional[str],
response: ClientResponse,
timeout: float,
autoclose: bool,
autoping: bool,
loop: asyncio.AbstractEventLoop,
*,
receive_timeout: Optional[float] = None,
heartbeat: Optional[float] = None,
compress: int = 0,
client_notakeover: bool = False,
) -> None:
self._response = response
self._conn = response.connection
self._writer = writer
self._reader = reader
self._protocol = protocol
self._closed = False
self._closing = False
self._close_code: Optional[int] = None
self._timeout = timeout
self._receive_timeout = receive_timeout
self._autoclose = autoclose
self._autoping = autoping
self._heartbeat = heartbeat
self._heartbeat_cb: Optional[asyncio.TimerHandle] = None
if heartbeat is not None:
self._pong_heartbeat = heartbeat / 2.0
self._pong_response_cb: Optional[asyncio.TimerHandle] = None
self._loop = loop
self._waiting: Optional[asyncio.Future[bool]] = None
self._exception: Optional[BaseException] = None
self._compress = compress
self._client_notakeover = client_notakeover
self._reset_heartbeat()
def _cancel_heartbeat(self) -> None:
if self._pong_response_cb is not None:
self._pong_response_cb.cancel()
self._pong_response_cb = None
if self._heartbeat_cb is not None:
self._heartbeat_cb.cancel()
self._heartbeat_cb = None
def _reset_heartbeat(self) -> None:
self._cancel_heartbeat()
if self._heartbeat is not None:
self._heartbeat_cb = call_later(
self._send_heartbeat, self._heartbeat, self._loop
)
def _send_heartbeat(self) -> None:
if self._heartbeat is not None and not self._closed:
# fire-and-forget a task is not perfect but maybe ok for
# sending ping. Otherwise we need a long-living heartbeat
# task in the class.
self._loop.create_task(self._writer.ping())
if self._pong_response_cb is not None:
self._pong_response_cb.cancel()
self._pong_response_cb = call_later(
self._pong_not_received, self._pong_heartbeat, self._loop
)
def _pong_not_received(self) -> None:
if not self._closed:
self._closed = True
self._close_code = WSCloseCode.ABNORMAL_CLOSURE
self._exception = asyncio.TimeoutError()
self._response.close()
@property
def closed(self) -> bool:
return self._closed
@property
def close_code(self) -> Optional[int]:
return self._close_code
@property
def protocol(self) -> Optional[str]:
return self._protocol
@property
def compress(self) -> int:
return self._compress
@property
def client_notakeover(self) -> bool:
return self._client_notakeover
def get_extra_info(self, name: str, default: Any = None) -> Any:
"""extra info from connection transport"""
conn = self._response.connection
if conn is None:
return default
transport = conn.transport
if transport is None:
return default
return transport.get_extra_info(name, default)
def exception(self) -> Optional[BaseException]:
return self._exception
async def ping(self, message: bytes = b"") -> None:
await self._writer.ping(message)
async def pong(self, message: bytes = b"") -> None:
await self._writer.pong(message)
async def send_str(self, data: str, compress: Optional[int] = None) -> None:
if not isinstance(data, str):
raise TypeError("data argument must be str (%r)" % type(data))
await self._writer.send(data, binary=False, compress=compress)
async def send_bytes(self, data: bytes, compress: Optional[int] = None) -> None:
if not isinstance(data, (bytes, bytearray, memoryview)):
raise TypeError("data argument must be byte-ish (%r)" % type(data))
await self._writer.send(data, binary=True, compress=compress)
async def send_json(
self,
data: Any,
compress: Optional[int] = None,
*,
dumps: JSONEncoder = DEFAULT_JSON_ENCODER,
) -> None:
await self.send_str(dumps(data), compress=compress)
async def close(self, *, code: int = WSCloseCode.OK, message: bytes = b"") -> bool:
# we need to break `receive()` cycle first,
# `close()` may be called from different task
if self._waiting is not None and not self._closed:
self._reader.feed_data(WS_CLOSING_MESSAGE, 0)
await self._waiting
if not self._closed:
self._cancel_heartbeat()
self._closed = True
try:
await self._writer.close(code, message)
except asyncio.CancelledError:
self._close_code = WSCloseCode.ABNORMAL_CLOSURE
self._response.close()
raise
except Exception as exc:
self._close_code = WSCloseCode.ABNORMAL_CLOSURE
self._exception = exc
self._response.close()
return True
if self._closing:
self._response.close()
return True
while True:
try:
async with async_timeout.timeout(self._timeout):
msg = await self._reader.read()
except asyncio.CancelledError:
self._close_code = WSCloseCode.ABNORMAL_CLOSURE
self._response.close()
raise
except Exception as exc:
self._close_code = WSCloseCode.ABNORMAL_CLOSURE
self._exception = exc
self._response.close()
return True
if msg.type == WSMsgType.CLOSE:
self._close_code = msg.data
self._response.close()
return True
else:
return False
async def receive(self, timeout: Optional[float] = None) -> WSMessage:
while True:
if self._waiting is not None:
raise RuntimeError("Concurrent call to receive() is not allowed")
if self._closed:
return WS_CLOSED_MESSAGE
elif self._closing:
await self.close()
return WS_CLOSED_MESSAGE
try:
self._waiting = self._loop.create_future()
try:
async with async_timeout.timeout(timeout or self._receive_timeout):
msg = await self._reader.read()
self._reset_heartbeat()
finally:
waiter = self._waiting
self._waiting = None
set_result(waiter, True)
except (asyncio.CancelledError, asyncio.TimeoutError):
self._close_code = WSCloseCode.ABNORMAL_CLOSURE
raise
except EofStream:
self._close_code = WSCloseCode.OK
await self.close()
return WSMessage(WSMsgType.CLOSED, None, None)
except ClientError:
self._closed = True
self._close_code = WSCloseCode.ABNORMAL_CLOSURE
return WS_CLOSED_MESSAGE
except WebSocketError as exc:
self._close_code = exc.code
await self.close(code=exc.code)
return WSMessage(WSMsgType.ERROR, exc, None)
except Exception as exc:
self._exception = exc
self._closing = True
self._close_code = WSCloseCode.ABNORMAL_CLOSURE
await self.close()
return WSMessage(WSMsgType.ERROR, exc, None)
if msg.type == WSMsgType.CLOSE:
self._closing = True
self._close_code = msg.data
if not self._closed and self._autoclose:
await self.close()
elif msg.type == WSMsgType.CLOSING:
self._closing = True
elif msg.type == WSMsgType.PING and self._autoping:
await self.pong(msg.data)
continue
elif msg.type == WSMsgType.PONG and self._autoping:
continue
return msg
async def receive_str(self, *, timeout: Optional[float] = None) -> str:
msg = await self.receive(timeout)
if msg.type != WSMsgType.TEXT:
raise TypeError(f"Received message {msg.type}:{msg.data!r} is not str")
return cast(str, msg.data)
async def receive_bytes(self, *, timeout: Optional[float] = None) -> bytes:
msg = await self.receive(timeout)
if msg.type != WSMsgType.BINARY:
raise TypeError(f"Received message {msg.type}:{msg.data!r} is not bytes")
return cast(bytes, msg.data)
async def receive_json(
self,
*,
loads: JSONDecoder = DEFAULT_JSON_DECODER,
timeout: Optional[float] = None,
) -> Any:
data = await self.receive_str(timeout=timeout)
return loads(data)
def __aiter__(self) -> "ClientWebSocketResponse":
return self
async def __anext__(self) -> WSMessage:
msg = await self.receive()
if msg.type in (WSMsgType.CLOSE, WSMsgType.CLOSING, WSMsgType.CLOSED):
raise StopAsyncIteration
return msg