Files
bitfinex-api-py/bfxapi/websocket/_client/bfx_websocket_bucket.py
2024-02-26 19:43:14 +01:00

152 lines
5.0 KiB
Python

import asyncio
import json
import uuid
from typing import Any, Dict, List, Optional, cast
import websockets.client
from pyee import EventEmitter
from bfxapi._utils.json_decoder import JSONDecoder
from bfxapi.websocket._connection import Connection
from bfxapi.websocket._handlers import PublicChannelsHandler
from bfxapi.websocket.subscriptions import Subscription
_CHECKSUM_FLAG_VALUE = 131_072
def _strip(message: Dict[str, Any], keys: List[str]) -> Dict[str, Any]:
return {key: value for key, value in message.items() if not key in keys}
class BfxWebSocketBucket(Connection):
__MAXIMUM_SUBSCRIPTIONS_AMOUNT = 25
def __init__(self, host: str, event_emitter: EventEmitter) -> None:
super().__init__(host)
self.__event_emitter = event_emitter
self.__pendings: List[Dict[str, Any]] = []
self.__subscriptions: Dict[int, Subscription] = {}
self.__condition = asyncio.locks.Condition()
self.__handler = PublicChannelsHandler(event_emitter=self.__event_emitter)
@property
def count(self) -> int:
return len(self.__pendings) + len(self.__subscriptions)
@property
def is_full(self) -> bool:
return self.count == BfxWebSocketBucket.__MAXIMUM_SUBSCRIPTIONS_AMOUNT
@property
def ids(self) -> List[str]:
return [pending["subId"] for pending in self.__pendings] + [
subscription["sub_id"] for subscription in self.__subscriptions.values()
]
async def start(self) -> None:
async with websockets.client.connect(self._host) as websocket:
self._websocket = websocket
await self.__recover_state()
async with self.__condition:
self.__condition.notify(1)
async for _message in self._websocket:
message = json.loads(_message, cls=JSONDecoder)
if isinstance(message, dict):
if message["event"] == "subscribed":
self.__on_subscribed(message)
if isinstance(message, list):
if (
(chan_id := cast(int, message[0]))
and (subscription := self.__subscriptions.get(chan_id))
and (message[1] != Connection._HEARTBEAT)
):
self.__handler.handle(subscription, message[1:])
def __on_subscribed(self, message: Dict[str, Any]) -> None:
chan_id = cast(int, message["chan_id"])
subscription = cast(
Subscription, _strip(message, keys=["chan_id", "event", "pair", "currency"])
)
self.__pendings = [
pending
for pending in self.__pendings
if pending["subId"] != message["sub_id"]
]
self.__subscriptions[chan_id] = subscription
self.__event_emitter.emit("subscribed", subscription)
async def __recover_state(self) -> None:
for pending in self.__pendings:
await self._websocket.send(message=json.dumps(pending))
for chan_id in list(self.__subscriptions.keys()):
subscription = self.__subscriptions.pop(chan_id)
await self.subscribe(**subscription)
await self.__set_config([_CHECKSUM_FLAG_VALUE])
async def __set_config(self, flags: List[int]) -> None:
await self._websocket.send(json.dumps({"event": "conf", "flags": sum(flags)}))
@Connection._require_websocket_connection
async def subscribe(
self, channel: str, sub_id: Optional[str] = None, **kwargs: Any
) -> None:
subscription: Dict[str, Any] = {
**kwargs,
"event": "subscribe",
"channel": channel,
}
subscription["subId"] = sub_id or str(uuid.uuid4())
self.__pendings.append(subscription)
await self._websocket.send(message=json.dumps(subscription))
@Connection._require_websocket_connection
async def unsubscribe(self, sub_id: str) -> None:
for chan_id, subscription in list(self.__subscriptions.items()):
if subscription["sub_id"] == sub_id:
unsubscription = {"event": "unsubscribe", "chanId": chan_id}
del self.__subscriptions[chan_id]
await self._websocket.send(message=json.dumps(unsubscription))
@Connection._require_websocket_connection
async def resubscribe(self, sub_id: str) -> None:
for subscription in list(self.__subscriptions.values()):
if subscription["sub_id"] == sub_id:
await self.unsubscribe(sub_id)
await self.subscribe(**subscription)
@Connection._require_websocket_connection
async def close(self, code: int = 1000, reason: str = str()) -> None:
await self._websocket.close(code, reason)
def has(self, sub_id: str) -> bool:
for subscription in self.__subscriptions.values():
if subscription["sub_id"] == sub_id:
return True
return False
async def wait(self) -> None:
async with self.__condition:
await self.__condition.wait_for(lambda: self.open)