""" The MIT License (MIT) Copyright (c) 2015-2021 Rapptz Copyright (c) 2021-present Pycord Development Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. """ from __future__ import annotations import asyncio import concurrent.futures import logging import sys import threading import time import traceback import zlib from collections.abc import Callable from typing import TYPE_CHECKING, Any, NamedTuple import aiohttp from . import utils from .activity import BaseActivity from .errors import ConnectionClosed, InvalidArgument if TYPE_CHECKING: from typing_extensions import Self from .client import Client from .state import ConnectionState _log = logging.getLogger(__name__) __all__ = ( "DiscordWebSocket", "KeepAliveHandler", "ReconnectWebSocket", ) class ReconnectWebSocket(Exception): """Signals to safely reconnect the WebSocket.""" def __init__(self, shard_id, *, resume=True): self.shard_id = shard_id self.resume = resume self.op = "RESUME" if resume else "IDENTIFY" class WebSocketClosure(Exception): """An exception to make up for the fact that aiohttp doesn't signal closure.""" class EventListener(NamedTuple): predicate: Callable[[dict[str, Any]], bool] event: str result: Callable[[dict[str, Any]], Any] | None future: asyncio.Future[Any] class GatewayRatelimiter: def __init__(self, count: int = 110, per: float = 60.0): # The default is 110 to give room for at least 10 heartbeats per minute self.max: int = count self.remaining: int = count self.window: float = 0.0 self.per: float = per self.lock: asyncio.Lock = asyncio.Lock() self.shard_id: int | None = None def is_ratelimited(self) -> bool: current = time.time() if current > self.window + self.per: return False return self.remaining == 0 def get_delay(self) -> float: current = time.time() if current > self.window + self.per: self.remaining = self.max if self.remaining == self.max: self.window = current if self.remaining == 0: return self.per - (current - self.window) self.remaining -= 1 if self.remaining == 0: self.window = current return 0.0 async def block(self) -> None: async with self.lock: delta = self.get_delay() if delta: _log.warning( "WebSocket in shard ID %s is ratelimited, waiting %.2f seconds", self.shard_id, delta, ) await asyncio.sleep(delta) class KeepAliveHandler(threading.Thread): def __init__( self, *args: Any, ws: DiscordWebSocket, shard_id: int | None = None, interval: float | None = None, **kwargs: Any, ) -> None: daemon: bool = kwargs.pop("daemon", True) name: str = kwargs.pop("name", f"keep-alive-handler:shard-{shard_id}") super().__init__( *args, **kwargs, daemon=daemon, name=name, ) self.ws: DiscordWebSocket = ws self._main_thread_id = ws.thread_id self.interval = interval self.shard_id = shard_id self.msg = "Keeping shard ID %s websocket alive with sequence %s." self.block_msg = "Shard ID %s heartbeat blocked for more than %s seconds." self.behind_msg = "Can't keep up, shard ID %s websocket is %.1fs behind." self._stop_ev = threading.Event() self._last_ack = time.perf_counter() self._last_send = time.perf_counter() self._last_recv = time.perf_counter() self.latency = float("inf") self.heartbeat_timeout = ws._max_heartbeat_timeout def run(self) -> None: while not self._stop_ev.wait(self.interval): if self._last_recv + self.heartbeat_timeout < time.perf_counter(): _log.warning( ( "Shard ID %s has stopped responding to the gateway. Closing and" " restarting." ), self.shard_id, ) coro = self.ws.close(4000) f = asyncio.run_coroutine_threadsafe(coro, loop=self.ws.loop) try: f.result() except Exception: _log.exception( "An error occurred while stopping the gateway. Ignoring." ) finally: self.stop() return data = self.get_payload() _log.debug(self.msg, self.shard_id, data["d"]) coro = self.ws.send_heartbeat(data) f = asyncio.run_coroutine_threadsafe(coro, loop=self.ws.loop) try: # block until sending is complete total = 0 while True: try: f.result(10) break except concurrent.futures.TimeoutError: total += 10 try: frame = sys._current_frames()[self._main_thread_id] except KeyError: msg = self.block_msg else: stack = "".join(traceback.format_stack(frame)) msg = ( f"{self.block_msg}\nLoop thread traceback (most recent" f" call last):\n{stack}" ) _log.warning(msg, self.shard_id, total) except Exception: self.stop() else: self._last_send = time.perf_counter() def get_payload(self) -> dict[str, Any]: return {"op": self.ws.HEARTBEAT, "d": self.ws.sequence} def stop(self) -> None: self._stop_ev.set() def tick(self) -> None: self._last_recv = time.perf_counter() def ack(self) -> None: ack_time = time.perf_counter() self._last_ack = ack_time self.latency = ack_time - self._last_send if self.latency > 10: _log.warning(self.behind_msg, self.shard_id, self.latency) class DiscordClientWebSocketResponse(aiohttp.ClientWebSocketResponse): async def close(self, *, code: int = 4000, message: bytes = b"") -> bool: return await super().close(code=code, message=message) class DiscordWebSocket: """Implements a WebSocket for Discord's gateway v6. Attributes ---------- DISPATCH Receive only. Denotes an event to be sent to Discord, such as READY. HEARTBEAT When received tells Discord to keep the connection alive. When sent asks if your connection is currently alive. IDENTIFY Send only. Starts a new session. PRESENCE Send only. Updates your presence. VOICE_STATE Send only. Starts a new connection to a voice guild. VOICE_PING Send only. Checks ping time to a voice guild, do not use. RESUME Send only. Resumes an existing connection. RECONNECT Receive only. Tells the client to reconnect to a new gateway. REQUEST_MEMBERS Send only. Asks for the full member list of a guild. INVALIDATE_SESSION Receive only. Tells the client to optionally invalidate the session and IDENTIFY again. HELLO Receive only. Tells the client the heartbeat interval. HEARTBEAT_ACK Receive only. Confirms receiving of a heartbeat. Not having one implies a connection issue. GUILD_SYNC Send only. Requests a guild sync. gateway The gateway we are currently connected to. token The authentication token for discord. """ DISPATCH = 0 HEARTBEAT = 1 IDENTIFY = 2 PRESENCE = 3 VOICE_STATE = 4 VOICE_PING = 5 RESUME = 6 RECONNECT = 7 REQUEST_MEMBERS = 8 INVALIDATE_SESSION = 9 HELLO = 10 HEARTBEAT_ACK = 11 GUILD_SYNC = 12 REQUEST_SOUNDBOARD_SOUNDS = 31 if TYPE_CHECKING: token: str | None _connection: ConnectionState _discord_parsers: dict[str, Callable[..., Any]] call_hooks: Callable[..., Any] gateway: str _initial_identify: bool shard_id: int | None shard_count: int | None _max_heartbeat_timeout: float def __init__( self, socket: aiohttp.ClientWebSocketResponse, *, loop: asyncio.AbstractEventLoop, ) -> None: self.socket: aiohttp.ClientWebSocketResponse = socket self.loop: asyncio.AbstractEventLoop = loop # an empty dispatcher to prevent crashes self._dispatch: Callable[..., Any] = lambda *args: None # generic event listeners self._dispatch_listeners: list[EventListener] = [] # the keep alive self._keep_alive: KeepAliveHandler | None = None self.thread_id: int = threading.get_ident() # ws related stuff self.session_id: str | None = None self.sequence: int | None = None self.resume_gateway_url: str | None = None self._zlib: zlib._Decompress = zlib.decompressobj() self._buffer: bytearray = bytearray() self._close_code: int | None = None self._rate_limiter: GatewayRatelimiter = GatewayRatelimiter() @property def open(self) -> bool: return not self.socket.closed def is_ratelimited(self) -> bool: return self._rate_limiter.is_ratelimited() def debug_log_receive(self, data: dict[str, Any], /) -> None: self._dispatch("socket_raw_receive", data) def log_receive(self, _: dict[str, Any], /) -> None: pass @classmethod async def from_client( cls, client: Client, *, initial: bool = False, gateway: str | None = None, shard_id: int | None = None, session: str | None = None, sequence: int | None = None, resume: bool = False, ) -> Self: """Creates a main websocket for Discord from a :class:`Client`. This is for internal use only. """ gateway = gateway or await client.http.get_gateway() socket = await client.http.ws_connect(gateway) ws = cls(socket, loop=client.loop) # dynamically add attributes needed ws.token = client.http.token ws._connection = client._connection ws._discord_parsers = client._connection.parsers ws._dispatch = client.dispatch ws.gateway = gateway ws.call_hooks = client._connection.call_hooks ws._initial_identify = initial ws.shard_id = shard_id ws._rate_limiter.shard_id = shard_id ws.shard_count = client._connection.shard_count ws.session_id = session ws.sequence = sequence ws._max_heartbeat_timeout = client._connection.heartbeat_timeout if client._enable_debug_events: ws.send = ws.debug_send ws.log_receive = ws.debug_log_receive client._connection._update_references(ws) _log.debug("Created websocket connected to %s", gateway) # poll event for OP Hello await ws.poll_event() if not resume: await ws.identify() return ws await ws.resume() return ws def wait_for( self, event: str, predicate: Callable[[dict[str, Any]], bool], result: Callable[[dict[str, Any]], Any] | None = None, ) -> asyncio.Future[Any]: """Waits for a DISPATCH'd event that meets the predicate. Parameters ---------- event: :class:`str` The event name in all upper case to wait for. predicate A function that takes a data parameter to check for event properties. The data parameter is the 'd' key in the JSON message. result A function that takes the same data parameter and executes to send the result to the future. If ``None``, returns the data. Returns ------- asyncio.Future A future to wait for. """ future = self.loop.create_future() entry = EventListener( event=event, predicate=predicate, result=result, future=future ) self._dispatch_listeners.append(entry) return future async def identify(self) -> None: """Sends the IDENTIFY packet.""" payload = { "op": self.IDENTIFY, "d": { "token": self.token, "properties": { "os": sys.platform, "browser": "pycord", "device": "pycord", }, "compress": True, "large_threshold": 250, }, } if self.shard_id is not None and self.shard_count is not None: payload["d"]["shard"] = [self.shard_id, self.shard_count] state = self._connection if state._activity is not None or state._status is not None: payload["d"]["presence"] = { "status": state._status, "game": state._activity, "since": 0, "afk": False, } if state._intents is not None: payload["d"]["intents"] = state._intents.value await self.call_hooks( "before_identify", self.shard_id, initial=self._initial_identify ) await self.send_as_json(payload) _log.info("Shard ID %s has sent the IDENTIFY payload.", self.shard_id) async def resume(self) -> None: """Sends the RESUME packet.""" payload = { "op": self.RESUME, "d": { "seq": self.sequence, "session_id": self.session_id, "token": self.token, }, } await self.send_as_json(payload) _log.info("Shard ID %s has sent the RESUME payload.", self.shard_id) async def received_message(self, msg: Any, /): if type(msg) is bytes: self._buffer.extend(msg) if len(msg) < 4 or msg[-4:] != b"\x00\x00\xff\xff": return msg = self._zlib.decompress(self._buffer) msg = msg.decode("utf-8") self._buffer = bytearray() self.log_receive(msg) msg = utils._from_json(msg) _log.debug("For Shard ID %s: WebSocket Event: %s", self.shard_id, msg) event = msg.get("t") if event: self._dispatch("socket_event_type", event) op = msg.get("op") data = msg.get("d") seq = msg.get("s") if seq is not None: self.sequence = seq if self._keep_alive: self._keep_alive.tick() if op != self.DISPATCH: if op == self.RECONNECT: # "reconnect" can only be handled by the Client, so we # terminate our connection and raise an # internal exception signalling to reconnect. _log.debug("Received RECONNECT opcode.") await self.close() raise ReconnectWebSocket(self.shard_id) if op == self.HEARTBEAT_ACK: if self._keep_alive: self._keep_alive.ack() return if op == self.HEARTBEAT: if self._keep_alive: beat = self._keep_alive.get_payload() await self.send_as_json(beat) return if op == self.HELLO: interval = data["heartbeat_interval"] / 1000.0 self._keep_alive = KeepAliveHandler( ws=self, interval=interval, shard_id=self.shard_id ) # send a heartbeat immediately await self.send_as_json(self._keep_alive.get_payload()) self._keep_alive.start() return if op == self.INVALIDATE_SESSION: if data is True: await self.close() raise ReconnectWebSocket(self.shard_id) self.sequence = None self.session_id = None _log.info("Shard ID %s session has been invalidated.", self.shard_id) await self.close(code=1000) raise ReconnectWebSocket(self.shard_id, resume=False) _log.warning("Unknown OP code %s.", op) return if event == "READY": self._trace = trace = data.get("_trace", []) self.sequence = msg["s"] self.session_id = data["session_id"] self.resume_gateway_url = data["resume_gateway_url"] # pass back shard ID to ready handler data["__shard_id__"] = self.shard_id _log.info( "Shard ID %s has connected to Gateway: %s (Session ID: %s).", self.shard_id, ", ".join(trace), self.session_id, ) elif event == "RESUMED": self._trace = trace = data.get("_trace", []) # pass back the shard ID to the resumed handler data["__shard_id__"] = self.shard_id _log.info( "Shard ID %s has successfully RESUMED session %s under trace %s.", self.shard_id, self.session_id, ", ".join(trace), ) try: func = self._discord_parsers[event] except KeyError: _log.debug("Unknown event %s.", event) else: func(data) # remove the dispatched listeners removed = [] for index, entry in enumerate(self._dispatch_listeners): if entry.event != event: continue future = entry.future if future.cancelled(): removed.append(index) continue try: valid = entry.predicate(data) except Exception as exc: future.set_exception(exc) removed.append(index) else: if valid: ret = data if entry.result is None else entry.result(data) future.set_result(ret) removed.append(index) for index in reversed(removed): del self._dispatch_listeners[index] @property def latency(self) -> float: """Measures latency between a HEARTBEAT and a HEARTBEAT_ACK in seconds. If no heartbeat has been received yet this returns ``float('inf')``. """ heartbeat = self._keep_alive return float("inf") if heartbeat is None else heartbeat.latency def _can_handle_close(self) -> bool: code = self._close_code or self.socket.close_code is_improper_close = self._close_code is None and self.socket.close_code == 1000 return is_improper_close or code not in ( 1000, 4004, 4010, 4011, 4012, 4013, 4014, ) async def poll_event(self) -> None: """Polls for a DISPATCH event and handles the general gateway loop. Raises ------ ConnectionClosed The websocket connection was terminated for unhandled reasons. """ try: msg = await self.socket.receive(timeout=self._max_heartbeat_timeout) if msg.type is aiohttp.WSMsgType.TEXT: await self.received_message(msg.data) elif msg.type is aiohttp.WSMsgType.BINARY: await self.received_message(msg.data) elif msg.type is aiohttp.WSMsgType.ERROR: _log.debug("Received an error %s", msg) elif msg.type in ( aiohttp.WSMsgType.CLOSED, aiohttp.WSMsgType.CLOSING, aiohttp.WSMsgType.CLOSE, ): _log.debug("Received %s", msg) raise WebSocketClosure except (asyncio.TimeoutError, WebSocketClosure) as e: # Ensure the keep alive handler is closed if self._keep_alive: self._keep_alive.stop() self._keep_alive = None if isinstance(e, asyncio.TimeoutError): _log.info("Timed out receiving packet. Attempting a reconnect.") raise ReconnectWebSocket(self.shard_id) from None code = self._close_code or self.socket.close_code if self._can_handle_close(): _log.info("Websocket closed with %s, attempting a reconnect.", code) raise ReconnectWebSocket(self.shard_id) from None else: _log.info("Websocket closed with %s, cannot reconnect.", code) raise ConnectionClosed( self.socket, shard_id=self.shard_id, code=code ) from None async def debug_send(self, data: str, /) -> None: await self._rate_limiter.block() self._dispatch("socket_raw_send", data) await self.socket.send_str(data) async def send(self, data: str, /) -> None: await self._rate_limiter.block() await self.socket.send_str(data) async def send_as_json(self, data: Any) -> None: try: await self.send(utils._to_json(data)) except RuntimeError as exc: if not self._can_handle_close(): raise ConnectionClosed(self.socket, shard_id=self.shard_id) from exc async def send_heartbeat(self, data: Any) -> None: # This bypasses the rate limit handling code since it has a higher priority try: await self.socket.send_str(utils._to_json(data)) except RuntimeError as exc: if not self._can_handle_close(): raise ConnectionClosed(self.socket, shard_id=self.shard_id) from exc async def change_presence( self, *, activity: BaseActivity | None = None, status: str | None = None, since: float = 0.0, ) -> None: if activity is not None: if not isinstance(activity, BaseActivity): raise InvalidArgument("activity must derive from BaseActivity.") activities = [activity.to_dict()] else: activities = [] if status == "idle": since = int(time.time() * 1000) payload = { "op": self.PRESENCE, "d": { "activities": activities, "afk": False, "since": since, "status": status, }, } sent = utils._to_json(payload) _log.debug('Sending "%s" to change status', sent) await self.send(sent) async def request_chunks( self, guild_id: int, query: str | None = None, *, limit: int, user_ids: list[int] | None = None, presences: bool = False, nonce: str | None = None, ) -> None: payload = { "op": self.REQUEST_MEMBERS, "d": {"guild_id": guild_id, "presences": presences, "limit": limit}, } if nonce: payload["d"]["nonce"] = nonce if user_ids: payload["d"]["user_ids"] = user_ids if query is not None: payload["d"]["query"] = query await self.send_as_json(payload) async def voice_state( self, guild_id: int, channel_id: int, self_mute: bool = False, self_deaf: bool = False, ) -> None: payload = { "op": self.VOICE_STATE, "d": { "guild_id": guild_id, "channel_id": channel_id, "self_mute": self_mute, "self_deaf": self_deaf, }, } _log.debug("Updating our voice state to %s.", payload) await self.send_as_json(payload) async def request_soundboard_sounds(self, guild_ids): payload = { "op": self.REQUEST_SOUNDBOARD_SOUNDS, "d": {"guild_ids": guild_ids}, } _log.debug("Requesting soundboard sounds for guilds %s.", guild_ids) await self.send_as_json(payload) async def close(self, code: int = 4000) -> None: if self._keep_alive: self._keep_alive.stop() self._keep_alive = None self._close_code = code await self.socket.close(code=code)