async def send(self, msg: dict) -> Any:
"""Send a request to Binance stream
and handle the asynchronous socket response
Request::
{
"method": "SUBSCRIBE",
"params": [
"btcusdt@aggTrade",
"btcusdt@depth"
],
"id": 1
}
Response::
{
"result": null,
"id": 1
}
Then the result of `self.send()` is `None` (null)
"""
socket = self._socket
if not socket:
if self._open_future:
socket = await self._open_future
else:
raise StreamDisconnectedException(self._uri)
future = create_future()
message_id = self._message_id
self._message_id += 1
msg[STREAM_KEY_ID] = message_id
self._message_futures[message_id] = future
await socket.send(json_stringify(msg))
return await future
async def close(self, code: int = DEFAULT_STREAM_CLOSE_CODE) -> None:
"""Close the current socket connection
Args:
code (:obj:`int`, optional): socket close code, defaults to 4999
"""
if not self._conn_task:
raise StreamDisconnectedException(self._uri)
# A lot of incomming messages might prevent
# the socket from gracefully shutting down,
# which leads `websockets` to fail connection
# and result in a 1006 close code (ConnectionClosedError).
# In that situation, we can not properly figure out whether the socket
# is closed by socket.close() or network connection error.
# So just set up a flag to do the trick
self._closing = True
tasks = [self._conn_task]
if self._socket:
tasks.append(
# make socket.close run in background
self._socket.close(code))
self._conn_task.cancel()
# Make sure:
# - conn_task is cancelled
# - socket is closed
for coro in asyncio.as_completed(tasks):
try:
await coro
except Exception as e:
logger.error(format_msg('close tasks error: %s', e))
self._socket = None
self._closing = False