Method sendPacket

packages/engine.io/lib/socket.ts:468–502

* Sends a packet. * * @param {String} type - packet type * @param {String} data * @param {Object} options * @param {Function} callback * * @private

(
    type: PacketType,
    data?: RawData,
    options: SendOptions = {},
    callback?: SendCallback,
  )

   * @private
   */
  private sendPacket(
    type: PacketType,
    data?: RawData,
    options: SendOptions = {},
    callback?: SendCallback,
  ) {
    if ("function" === typeof options) {
      callback = options;
      options = {};
    }

    if ("closing" !== this.readyState && "closed" !== this.readyState) {
      debug('sending packet "%s" (%s)', type, data);

      // compression is enabled by default
      options.compress = options.compress !== false;

      const packet: Packet = {
        type,
        options: options as { compress: boolean },
      };

      if (data) packet.data = data;

      // exports packetCreate event
      this.emit("packetCreate", packet);

      this.writeBuffer.push(packet);

      // add send callback to object, if defined
      if ("function" === typeof callback) this.packetsFn.push(callback);

      this.flush();
    }
  }

  /**
   * Attempts to flush the packets buffer.