Socket.js

/**
 * @license
 * [BSD-3-Clause](https://github.com/pryv/lib-js/blob/master/LICENSE)
 */

const UpdateMethod = require('./UpdateMethod');
const Changes = require('../lib/Changes');

/**
 * Update method that uses @pryv/socket.io events for real-time updates.
 * Requires @pryv/socket.io to be loaded.
 * @memberof pryv.Monitor
 * @extends UpdateMethod
 */
class Socket extends UpdateMethod {
  async ready () {
    if (this.socket) return;
    // @ts-ignore - socket is added by @pryv/socket.io extension
    if (!this.monitor.connection.socket) {
      throw new Error('You should load package @pryv/socket.io to use monitor with websockets');
    }
    // @ts-ignore - socket is added by @pryv/socket.io extension
    this.socket = await this.monitor.connection.socket.open();
    this.socket.on('eventsChanged', () => { this.monitor.updateEvents(); });
    this.socket.on('streamsChanged', () => { this.monitor.updateStreams(); });
    this.socket.on('error', (error) => {
      this.monitor.emit(Changes.ERROR, error);
      // If the underlying socket.io-client transport has been torn down
      // (i.e. SocketIO emitted 'error' after reconnect_failed), drop our
      // reference so a future Changes.READY can rebuild instead of
      // short-circuiting on the cached, dead handle.
      if (this.socket && !this.socket._io) {
        this.socket = null;
      }
    });
  }

  async stop () {
    if (!this.socket) return;
    try { this.socket.close(); } catch (e) { }
    this.socket = null;
  }
}
module.exports = Socket;