Move voice UDP client and Websocket client to networking folder

src/client/voice/networking/VoiceUDPClient.js

@@ -0,0 +1,149 @@
+const udp = require('dgram');
+const dns = require('dns');
+const { VoiceOPCodes } = require('../../util/Constants');
+const EventEmitter = require('events');
+const { Error } = require('../../errors');
+
+/**
+ * Represents a UDP client for a Voice Connection.
+ * @extends {EventEmitter}
+ * @private
+ */
+class VoiceConnectionUDPClient extends EventEmitter {
+  constructor(voiceConnection) {
+    super();
+
+    /**
+     * The voice connection that this UDP client serves
+     * @type {VoiceConnection}
+     */
+    this.voiceConnection = voiceConnection;
+
+    /**
+     * The UDP socket
+     * @type {?Socket}
+     */
+    this.socket = null;
+
+    /**
+     * The address of the Discord voice server
+     * @type {?string}
+     */
+    this.discordAddress = null;
+
+    /**
+     * The local IP address
+     * @type {?string}
+     */
+    this.localAddress = null;
+
+    /**
+     * The local port
+     * @type {?string}
+     */
+    this.localPort = null;
+
+    this.voiceConnection.on('closing', this.shutdown.bind(this));
+  }
+
+  shutdown() {
+    if (this.socket) {
+      this.socket.removeAllListeners('message');
+      try {
+        this.socket.close();
+      } finally {
+        this.socket = null;
+      }
+    }
+  }
+
+  /**
+   * The port of the Discord voice server
+   * @type {number}
+   * @readonly
+   */
+  get discordPort() {
+    return this.voiceConnection.authentication.port;
+  }
+
+  /**
+   * Tries to resolve the voice server endpoint to an address.
+   * @returns {Promise<string>}
+   */
+  findEndpointAddress() {
+    return new Promise((resolve, reject) => {
+      dns.lookup(this.voiceConnection.authentication.endpoint, (error, address) => {
+        if (error) {
+          reject(error);
+          return;
+        }
+        this.discordAddress = address;
+        resolve(address);
+      });
+    });
+  }
+
+  /**
+   * Send a packet to the UDP client.
+   * @param {Object} packet The packet to send
+   * @returns {Promise<Object>}
+   */
+  send(packet) {
+    return new Promise((resolve, reject) => {
+      if (!this.socket) throw new Error('UDP_SEND_FAIL');
+      if (!this.discordAddress || !this.discordPort) throw new Error('UDP_ADDRESS_MALFORMED');
+      this.socket.send(packet, 0, packet.length, this.discordPort, this.discordAddress, error => {
+        if (error) reject(error); else resolve(packet);
+      });
+    });
+  }
+
+  createUDPSocket(address) {
+    this.discordAddress = address;
+    const socket = this.socket = udp.createSocket('udp4');
+
+    socket.once('message', message => {
+      // Stop if the sockets have been deleted because the connection has been closed already
+      if (!this.voiceConnection.sockets.ws) return;
+
+      const packet = parseLocalPacket(message);
+      if (packet.error) {
+        this.emit('error', packet.error);
+        return;
+      }
+
+      this.localAddress = packet.address;
+      this.localPort = packet.port;
+
+      this.voiceConnection.sockets.ws.sendPacket({
+        op: VoiceOPCodes.SELECT_PROTOCOL,
+        d: {
+          protocol: 'udp',
+          data: {
+            address: packet.address,
+            port: packet.port,
+            mode: 'xsalsa20_poly1305',
+          },
+        },
+      });
+    });
+
+    const blankMessage = Buffer.alloc(70);
+    blankMessage.writeUIntBE(this.voiceConnection.authentication.ssrc, 0, 4);
+    this.send(blankMessage);
+  }
+}
+
+function parseLocalPacket(message) {
+  try {
+    const packet = Buffer.from(message);
+    let address = '';
+    for (let i = 4; i < packet.indexOf(0, i); i++) address += String.fromCharCode(packet[i]);
+    const port = parseInt(packet.readUIntLE(packet.length - 2, 2).toString(10), 10);
+    return { address, port };
+  } catch (error) {
+    return { error };
+  }
+}
+
+module.exports = VoiceConnectionUDPClient;

src/client/voice/networking/VoiceWebSocket.js

@@ -0,0 +1,242 @@
+const { OPCodes, VoiceOPCodes } = require('../../util/Constants');
+const EventEmitter = require('events');
+const { Error } = require('../../errors');
+const WebSocket = require('../../WebSocket');
+
+/**
+ * Represents a Voice Connection's WebSocket.
+ * @extends {EventEmitter}
+ * @private
+ */
+class VoiceWebSocket extends EventEmitter {
+  constructor(voiceConnection) {
+    super();
+
+    /**
+     * The client of this voice WebSocket
+     * @type {Client}
+     */
+    this.client = voiceConnection.voiceManager.client;
+
+    /**
+     * The Voice Connection that this WebSocket serves
+     * @type {VoiceConnection}
+     */
+    this.voiceConnection = voiceConnection;
+
+    /**
+     * How many connection attempts have been made
+     * @type {number}
+     */
+    this.attempts = 0;
+
+    this.connect();
+    this.dead = false;
+    this.voiceConnection.on('closing', this.shutdown.bind(this));
+  }
+
+  shutdown() {
+    this.dead = true;
+    this.reset();
+  }
+
+  /**
+   * Resets the current WebSocket.
+   */
+  reset() {
+    if (this.ws) {
+      if (this.ws.readyState !== WebSocket.CLOSED) this.ws.close();
+      this.ws = null;
+    }
+    this.clearHeartbeat();
+  }
+
+  /**
+   * Starts connecting to the Voice WebSocket Server.
+   */
+  connect() {
+    if (this.dead) return;
+    if (this.ws) this.reset();
+    if (this.attempts >= 5) {
+      this.emit('debug', new Error('VOICE_CONNECTION_ATTEMPTS_EXCEEDED', this.attempts));
+      return;
+    }
+
+    this.attempts++;
+
+    /**
+     * The actual WebSocket used to connect to the Voice WebSocket Server.
+     * @type {WebSocket}
+     */
+    this.ws = WebSocket.create(`wss://${this.voiceConnection.authentication.endpoint}/`, { v: 3 });
+    this.ws.onopen = this.onOpen.bind(this);
+    this.ws.onmessage = this.onMessage.bind(this);
+    this.ws.onclose = this.onClose.bind(this);
+    this.ws.onerror = this.onError.bind(this);
+  }
+
+  /**
+   * Sends data to the WebSocket if it is open.
+   * @param {string} data The data to send to the WebSocket
+   * @returns {Promise<string>}
+   */
+  send(data) {
+    return new Promise((resolve, reject) => {
+      if (!this.ws || this.ws.readyState !== WebSocket.OPEN) throw new Error('WS_NOT_OPEN', data);
+      this.ws.send(data, null, error => {
+        if (error) reject(error); else resolve(data);
+      });
+    });
+  }
+
+  /**
+   * JSON.stringify's a packet and then sends it to the WebSocket Server.
+   * @param {Object} packet The packet to send
+   * @returns {Promise<string>}
+   */
+  sendPacket(packet) {
+    try {
+      packet = JSON.stringify(packet);
+    } catch (error) {
+      return Promise.reject(error);
+    }
+    return this.send(packet);
+  }
+
+  /**
+   * Called whenever the WebSocket opens.
+   */
+  onOpen() {
+    this.sendPacket({
+      op: OPCodes.DISPATCH,
+      d: {
+        server_id: this.voiceConnection.channel.guild.id,
+        user_id: this.client.user.id,
+        token: this.voiceConnection.authentication.token,
+        session_id: this.voiceConnection.authentication.sessionID,
+      },
+    }).catch(() => {
+      this.emit('error', new Error('VOICE_JOIN_SOCKET_CLOSED'));
+    });
+  }
+
+  /**
+   * Called whenever a message is received from the WebSocket.
+   * @param {MessageEvent} event The message event that was received
+   * @returns {void}
+   */
+  onMessage(event) {
+    try {
+      return this.onPacket(WebSocket.unpack(event.data));
+    } catch (error) {
+      return this.onError(error);
+    }
+  }
+
+  /**
+   * Called whenever the connection to the WebSocket server is lost.
+   */
+  onClose() {
+    if (!this.dead) this.client.setTimeout(this.connect.bind(this), this.attempts * 1000);
+  }
+
+  /**
+   * Called whenever an error occurs with the WebSocket.
+   * @param {Error} error The error that occurred
+   */
+  onError(error) {
+    this.emit('error', error);
+  }
+
+  /**
+   * Called whenever a valid packet is received from the WebSocket.
+   * @param {Object} packet The received packet
+   */
+  onPacket(packet) {
+    switch (packet.op) {
+      case VoiceOPCodes.READY:
+        // *.75 to correct for discord devs taking longer to fix things than i do to release versions
+        this.setHeartbeat(packet.d.heartbeat_interval * 0.75);
+        /**
+         * Emitted once the voice WebSocket receives the ready packet.
+         * @param {Object} packet The received packet
+         * @event VoiceWebSocket#ready
+         */
+        this.emit('ready', packet.d);
+        break;
+      /* eslint-disable no-case-declarations */
+      case VoiceOPCodes.SESSION_DESCRIPTION:
+        const key = new Uint8Array(new ArrayBuffer(packet.d.secret_key.length));
+        for (const i in packet.d.secret_key) key[i] = packet.d.secret_key[i];
+        /**
+         * Emitted once the Voice Websocket receives a description of this voice session.
+         * @param {string} encryptionMode The type of encryption being used
+         * @param {Uint8Array} secretKey The secret key used for encryption
+         * @event VoiceWebSocket#sessionDescription
+         */
+        this.emit('sessionDescription', packet.d.mode, key);
+        break;
+      case VoiceOPCodes.SPEAKING:
+        /**
+         * Emitted whenever a speaking packet is received.
+         * @param {Object} data
+         * @event VoiceWebSocket#speaking
+         */
+        this.emit('speaking', packet.d);
+        break;
+      default:
+        /**
+         * Emitted when an unhandled packet is received.
+         * @param {Object} packet
+         * @event VoiceWebSocket#unknownPacket
+         */
+        this.emit('unknownPacket', packet);
+        break;
+    }
+  }
+
+  /**
+   * Sets an interval at which to send a heartbeat packet to the WebSocket.
+   * @param {number} interval The interval at which to send a heartbeat packet
+   */
+  setHeartbeat(interval) {
+    if (!interval || isNaN(interval)) {
+      this.onError(new Error('VOICE_INVALID_HEARTBEAT'));
+      return;
+    }
+    if (this.heartbeatInterval) {
+      /**
+       * Emitted whenver the voice WebSocket encounters a non-fatal error.
+       * @param {string} warn The warning
+       * @event VoiceWebSocket#warn
+       */
+      this.emit('warn', 'A voice heartbeat interval is being overwritten');
+      clearInterval(this.heartbeatInterval);
+    }
+    this.heartbeatInterval = this.client.setInterval(this.sendHeartbeat.bind(this), interval);
+  }
+
+  /**
+   * Clears a heartbeat interval, if one exists.
+   */
+  clearHeartbeat() {
+    if (!this.heartbeatInterval) {
+      this.emit('warn', 'Tried to clear a heartbeat interval that does not exist');
+      return;
+    }
+    clearInterval(this.heartbeatInterval);
+    this.heartbeatInterval = null;
+  }
+
+  /**
+   * Sends a heartbeat packet.
+   */
+  sendHeartbeat() {
+    this.sendPacket({ op: VoiceOPCodes.HEARTBEAT, d: null }).catch(() => {
+      this.emit('warn', 'Tried to send heartbeat, but connection is not open');
+      this.clearHeartbeat();
+    });
+  }
+}
+
+module.exports = VoiceWebSocket;