# -*- coding: utf-8 -*- """ The MIT License (MIT) Copyright (c) 2015-2020 Rapptz 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. """ """Some documentation to refer to: - Our main web socket (mWS) sends opcode 4 with a guild ID and channel ID. - The mWS receives VOICE_STATE_UPDATE and VOICE_SERVER_UPDATE. - We pull the session_id from VOICE_STATE_UPDATE. - We pull the token, endpoint and server_id from VOICE_SERVER_UPDATE. - Then we initiate the voice web socket (vWS) pointing to the endpoint. - We send opcode 0 with the user_id, server_id, session_id and token using the vWS. - The vWS sends back opcode 2 with an ssrc, port, modes(array) and hearbeat_interval. - We send a UDP discovery packet to endpoint:port and receive our IP and our port in LE. - Then we send our IP and port via vWS with opcode 1. - When that's all done, we receive opcode 4 from the vWS. - Finally we can transmit data to endpoint:port. """ import asyncio import socket import logging import struct import threading from . import opus from .backoff import ExponentialBackoff from .gateway import * from .errors import ClientException, ConnectionClosed from .player import AudioPlayer, AudioSource try: import nacl.secret has_nacl = True except ImportError: has_nacl = False log = logging.getLogger(__name__) class VoiceClient: """Represents a Discord voice connection. You do not create these, you typically get them from e.g. :meth:`VoiceChannel.connect`. Warning -------- In order to use PCM based AudioSources, you must have the opus library installed on your system and loaded through :func:`opus.load_opus`. Otherwise, your AudioSources must be opus encoded (e.g. using :class:`FFmpegOpusAudio`) or the library will not be able to transmit audio. Attributes ----------- session_id: :class:`str` The voice connection session ID. token: :class:`str` The voice connection token. endpoint: :class:`str` The endpoint we are connecting to. channel: :class:`abc.Connectable` The voice channel connected to. loop: :class:`asyncio.AbstractEventLoop` The event loop that the voice client is running on. """ def __init__(self, state, timeout, channel): if not has_nacl: raise RuntimeError("PyNaCl library needed in order to use voice") self.channel = channel self.main_ws = None self.timeout = timeout self.ws = None self.socket = None self.loop = state.loop self._state = state # this will be used in the AudioPlayer thread self._connected = threading.Event() self._handshaking = False self._handshake_check = asyncio.Lock() self._handshake_complete = asyncio.Event() self.mode = None self._connections = 0 self.sequence = 0 self.timestamp = 0 self._runner = None self._player = None self.encoder = None self._lite_nonce = 0 warn_nacl = not has_nacl supported_modes = ( 'xsalsa20_poly1305_lite', 'xsalsa20_poly1305_suffix', 'xsalsa20_poly1305', ) @property def guild(self): """Optional[:class:`Guild`]: The guild we're connected to, if applicable.""" return getattr(self.channel, 'guild', None) @property def user(self): """:class:`ClientUser`: The user connected to voice (i.e. ourselves).""" return self._state.user def checked_add(self, attr, value, limit): val = getattr(self, attr) if val + value > limit: setattr(self, attr, 0) else: setattr(self, attr, val + value) # connection related async def start_handshake(self): log.info('Starting voice handshake...') guild_id, channel_id = self.channel._get_voice_state_pair() state = self._state self.main_ws = ws = state._get_websocket(guild_id) self._connections += 1 # request joining await ws.voice_state(guild_id, channel_id) try: await asyncio.wait_for(self._handshake_complete.wait(), timeout=self.timeout) except asyncio.TimeoutError: await self.terminate_handshake(remove=True) raise log.info('Voice handshake complete. Endpoint found %s (IP: %s)', self.endpoint, self.endpoint_ip) async def terminate_handshake(self, *, remove=False): guild_id, channel_id = self.channel._get_voice_state_pair() self._handshake_complete.clear() await self.main_ws.voice_state(guild_id, None, self_mute=True) log.info('The voice handshake is being terminated for Channel ID %s (Guild ID %s)', channel_id, guild_id) if remove: log.info('The voice client has been removed for Channel ID %s (Guild ID %s)', channel_id, guild_id) key_id, _ = self.channel._get_voice_client_key() self._state._remove_voice_client(key_id) async def _create_socket(self, server_id, data): async with self._handshake_check: if self._handshaking: log.info("Ignoring voice server update while handshake is in progress") return self._handshaking = True self._connected.clear() self.session_id = self.main_ws.session_id self.server_id = server_id self.token = data.get('token') endpoint = data.get('endpoint') if endpoint is None or self.token is None: log.warning('Awaiting endpoint... This requires waiting. ' \ 'If timeout occurred considering raising the timeout and reconnecting.') return self.endpoint = endpoint.replace(':80', '') self.endpoint_ip = socket.gethostbyname(self.endpoint) if self.socket: try: self.socket.close() except Exception: pass self.socket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM) self.socket.setblocking(False) if self._handshake_complete.is_set(): # terminate the websocket and handle the reconnect loop if necessary. self._handshake_complete.clear() await self.ws.close(4000) return self._handshake_complete.set() async def connect(self, *, reconnect=True, _tries=0, do_handshake=True): log.info('Connecting to voice...') try: del self.secret_key except AttributeError: pass if do_handshake: await self.start_handshake() try: self.ws = await DiscordVoiceWebSocket.from_client(self) self._handshaking = False self._connected.clear() while not hasattr(self, 'secret_key'): await self.ws.poll_event() self._connected.set() except (ConnectionClosed, asyncio.TimeoutError): if reconnect and _tries < 5: log.exception('Failed to connect to voice... Retrying...') await asyncio.sleep(1 + _tries * 2.0) await self.terminate_handshake() await self.connect(reconnect=reconnect, _tries=_tries + 1) else: raise if self._runner is None: self._runner = self.loop.create_task(self.poll_voice_ws(reconnect)) async def poll_voice_ws(self, reconnect): backoff = ExponentialBackoff() while True: try: await self.ws.poll_event() except (ConnectionClosed, asyncio.TimeoutError) as exc: if isinstance(exc, ConnectionClosed): # The following close codes are undocumented so I will document them here. # 1000 - normal closure (obviously) # 4014 - voice channel has been deleted. # 4015 - voice server has crashed if exc.code in (1000, 4014, 4015): log.info('Disconnecting from voice normally, close code %d.', exc.code) await self.disconnect() break if not reconnect: await self.disconnect() raise retry = backoff.delay() log.exception('Disconnected from voice... Reconnecting in %.2fs.', retry) self._connected.clear() await asyncio.sleep(retry) await self.terminate_handshake() try: await self.connect(reconnect=True) except asyncio.TimeoutError: # at this point we've retried 5 times... let's continue the loop. log.warning('Could not connect to voice... Retrying...') continue async def disconnect(self, *, force=False): """|coro| Disconnects this voice client from voice. """ if not force and not self.is_connected(): return self.stop() self._connected.clear() try: if self.ws: await self.ws.close() await self.terminate_handshake(remove=True) finally: if self.socket: self.socket.close() async def move_to(self, channel): """|coro| Moves you to a different voice channel. Parameters ----------- channel: :class:`abc.Snowflake` The channel to move to. Must be a voice channel. """ guild_id, _ = self.channel._get_voice_state_pair() await self.main_ws.voice_state(guild_id, channel.id) def is_connected(self): """Indicates if the voice client is connected to voice.""" return self._connected.is_set() # audio related def _get_voice_packet(self, data): header = bytearray(12) # Formulate rtp header header[0] = 0x80 header[1] = 0x78 struct.pack_into('>H', header, 2, self.sequence) struct.pack_into('>I', header, 4, self.timestamp) struct.pack_into('>I', header, 8, self.ssrc) encrypt_packet = getattr(self, '_encrypt_' + self.mode) return encrypt_packet(header, data) def _encrypt_xsalsa20_poly1305(self, header, data): box = nacl.secret.SecretBox(bytes(self.secret_key)) nonce = bytearray(24) nonce[:12] = header return header + box.encrypt(bytes(data), bytes(nonce)).ciphertext def _encrypt_xsalsa20_poly1305_suffix(self, header, data): box = nacl.secret.SecretBox(bytes(self.secret_key)) nonce = nacl.utils.random(nacl.secret.SecretBox.NONCE_SIZE) return header + box.encrypt(bytes(data), nonce).ciphertext + nonce def _encrypt_xsalsa20_poly1305_lite(self, header, data): box = nacl.secret.SecretBox(bytes(self.secret_key)) nonce = bytearray(24) nonce[:4] = struct.pack('>I', self._lite_nonce) self.checked_add('_lite_nonce', 1, 4294967295) return header + box.encrypt(bytes(data), bytes(nonce)).ciphertext + nonce[:4] def play(self, source, *, after=None): """Plays an :class:`AudioSource`. The finalizer, ``after`` is called after the source has been exhausted or an error occurred. If an error happens while the audio player is running, the exception is caught and the audio player is then stopped. If no after callback is passed, any caught exception will be displayed as if it were raised. Parameters ----------- source: :class:`AudioSource` The audio source we're reading from. after: Callable[[:class:`Exception`], Any] The finalizer that is called after the stream is exhausted. This function must have a single parameter, ``error``, that denotes an optional exception that was raised during playing. Raises ------- ClientException Already playing audio or not connected. TypeError Source is not a :class:`AudioSource` or after is not a callable. OpusNotLoaded Source is not opus encoded and opus is not loaded. """ if not self.is_connected(): raise ClientException('Not connected to voice.') if self.is_playing(): raise ClientException('Already playing audio.') if not isinstance(source, AudioSource): raise TypeError('source must an AudioSource not {0.__class__.__name__}'.format(source)) if not self.encoder and not source.is_opus(): self.encoder = opus.Encoder() self._player = AudioPlayer(source, self, after=after) self._player.start() def is_playing(self): """Indicates if we're currently playing audio.""" return self._player is not None and self._player.is_playing() def is_paused(self): """Indicates if we're playing audio, but if we're paused.""" return self._player is not None and self._player.is_paused() def stop(self): """Stops playing audio.""" if self._player: self._player.stop() self._player = None def pause(self): """Pauses the audio playing.""" if self._player: self._player.pause() def resume(self): """Resumes the audio playing.""" if self._player: self._player.resume() @property def source(self): """Optional[:class:`AudioSource`]: The audio source being played, if playing. This property can also be used to change the audio source currently being played. """ return self._player.source if self._player else None @source.setter def source(self, value): if not isinstance(value, AudioSource): raise TypeError('expected AudioSource not {0.__class__.__name__}.'.format(value)) if self._player is None: raise ValueError('Not playing anything.') self._player._set_source(value) def send_audio_packet(self, data, *, encode=True): """Sends an audio packet composed of the data. You must be connected to play audio. Parameters ---------- data: :class:`bytes` The :term:`py:bytes-like object` denoting PCM or Opus voice data. encode: :class:`bool` Indicates if ``data`` should be encoded into Opus. Raises ------- ClientException You are not connected. opus.OpusError Encoding the data failed. """ self.checked_add('sequence', 1, 65535) if encode: encoded_data = self.encoder.encode(data, self.encoder.SAMPLES_PER_FRAME) else: encoded_data = data packet = self._get_voice_packet(encoded_data) try: self.socket.sendto(packet, (self.endpoint_ip, self.voice_port)) except BlockingIOError: log.warning('A packet has been dropped (seq: %s, timestamp: %s)', self.sequence, self.timestamp) self.checked_add('timestamp', opus.Encoder.SAMPLES_PER_FRAME, 4294967295)