rocket.chat.mqtt/node_modules/ws/lib/Constants.js

It's a MQTT Server, using redis to scale horizontally.

'use strict';

const safeBuffer = require('safe-buffer');

const Buffer = safeBuffer.Buffer;

exports.BINARY_TYPES = ['nodebuffer', 'arraybuffer', 'fragments'];
exports.GUID = '258EAFA5-E914-47DA-95CA-C5AB0DC85B11';
exports.EMPTY_BUFFER = Buffer.alloc(0);
exports.NOOP = () => {};