socket io

app.js

const express = require('express')
const { createServer } = require('http')

const app = express()

const httpServer = createServer(app)

/** connect */
sockets.connect(httpServer)

sockets.emit('connection', { message: 'This is an event!' })

sockets.js

const { Server } = require('socket.io')
let io = null

module.exports = {
    connect: function (httpServer) {
        io = new Server(httpServer, {
            cors: {
                origin: '*',
            },
        })
    },

    emit: function (event, values) {
        if (io) {
            io.sockets.emit(event, values)
        }
    },
}