stable/freqtrade/rpc/api_server/ws/channel.py
2022-09-10 15:12:18 -06:00

180 lines
5.0 KiB
Python

import logging
from threading import RLock
from typing import List, Optional, Type
from uuid import uuid4
from fastapi import WebSocket as FastAPIWebSocket
from freqtrade.rpc.api_server.ws.proxy import WebSocketProxy
from freqtrade.rpc.api_server.ws.serializer import (HybridJSONWebSocketSerializer,
WebSocketSerializer)
from freqtrade.rpc.api_server.ws.types import WebSocketType
logger = logging.getLogger(__name__)
class WebSocketChannel:
"""
Object to help facilitate managing a websocket connection
"""
def __init__(
self,
websocket: WebSocketType,
channel_id: Optional[str] = None,
serializer_cls: Type[WebSocketSerializer] = HybridJSONWebSocketSerializer
):
self.channel_id = channel_id if channel_id else uuid4().hex[:8]
# The WebSocket object
self._websocket = WebSocketProxy(websocket)
# The Serializing class for the WebSocket object
self._serializer_cls = serializer_cls
self._subscriptions: List[str] = []
# Internal event to signify a closed websocket
self._closed = False
# Wrap the WebSocket in the Serializing class
self._wrapped_ws = self._serializer_cls(self._websocket)
def __repr__(self):
return f"WebSocketChannel({self.channel_id}, {self.remote_addr})"
@property
def remote_addr(self):
return self._websocket.remote_addr
async def send(self, data):
"""
Send data on the wrapped websocket
"""
await self._wrapped_ws.send(data)
async def recv(self):
"""
Receive data on the wrapped websocket
"""
return await self._wrapped_ws.recv()
async def ping(self):
"""
Ping the websocket
"""
return await self._websocket.ping()
async def close(self):
"""
Close the WebSocketChannel
"""
await self._websocket.close()
self._closed = True
def is_closed(self) -> bool:
"""
Closed flag
"""
return self._closed
def set_subscriptions(self, subscriptions: List[str] = []) -> None:
"""
Set which subscriptions this channel is subscribed to
:param subscriptions: List of subscriptions, List[str]
"""
self._subscriptions = subscriptions
def subscribed_to(self, message_type: str) -> bool:
"""
Check if this channel is subscribed to the message_type
:param message_type: The message type to check
"""
return message_type in self._subscriptions
class ChannelManager:
def __init__(self):
self.channels = dict()
self._lock = RLock() # Re-entrant Lock
async def on_connect(self, websocket: WebSocketType):
"""
Wrap websocket connection into Channel and add to list
:param websocket: The WebSocket object to attach to the Channel
"""
if isinstance(websocket, FastAPIWebSocket):
try:
await websocket.accept()
except RuntimeError:
# The connection was closed before we could accept it
return
ws_channel = WebSocketChannel(websocket)
with self._lock:
self.channels[websocket] = ws_channel
return ws_channel
async def on_disconnect(self, websocket: WebSocketType):
"""
Call close on the channel if it's not, and remove from channel list
:param websocket: The WebSocket objet attached to the Channel
"""
with self._lock:
channel = self.channels.get(websocket)
if channel:
if not channel.is_closed():
await channel.close()
del self.channels[websocket]
async def disconnect_all(self):
"""
Disconnect all Channels
"""
with self._lock:
for websocket, channel in self.channels.items():
if not channel.is_closed():
await channel.close()
self.channels = dict()
async def broadcast(self, data):
"""
Broadcast data on all Channels
:param data: The data to send
"""
with self._lock:
message_type = data.get('type')
for websocket, channel in self.channels.items():
try:
if channel.subscribed_to(message_type):
await channel.send(data)
except RuntimeError:
# Handle cannot send after close cases
await self.on_disconnect(websocket)
async def send_direct(self, channel, data):
"""
Send data directly through direct_channel only
:param direct_channel: The WebSocketChannel object to send data through
:param data: The data to send
"""
await channel.send(data)
def has_channels(self):
"""
Flag for more than 0 channels
"""
return len(self.channels) > 0