websocket performance test using ws

README.md

npm install bluebird ws
node server.js
node client.js

client.js

const Promise = require('bluebird')
const WebSocket = require('ws')
const nbr = 200

const now = () => {
    return new Date().getTime()
}

function Client(id) {
    this.ws = null
    this.start = function() {
        const that = this
        this.ws = new WebSocket('ws://10.1.8.87:8080')
        //this.ws = new WebSocket('ws://localhost:8080')
        this.ws.on('open', function() {
            console.log(`client ${id} connected`)
            that.send()
            that.ws.on('message', function(data) {
                var msg=JSON.parse(data)
                if(msg.start) {
                    msg.roudntrip=now() - msg.start     // roundtrip time in ms
                    data=JSON.stringify(msg)
                }
                console.log('received from server: ', data)
                setTimeout(function() {
                    that.send()
                }, Math.random()*1000)
            })
        })    
    }
    this.send = function() {
        const data = {
            move: {
                x: Math.random(),
                y: Math.random() 
            },
            start: now()
        }
        this.ws.send(JSON.stringify(data))
    }
}

const ids = Array.from(new Array(nbr), (x,i) => i)

Promise.map(ids, (id) => {
    const c = new Client(id)
    c.start()
    return Promise.resolve()
}).then(() => {
    console.log('all up')
})    

server.js

const WebSocket = require('ws')
const wss = new WebSocket.Server({
    port: 8080
})

const now = () => {
    return new Date().getTime()
}

wss.on('connection', (ws) => {
    ws.on('message', function(data) {
        var msg=JSON.parse(data)
        msg.took=now() - msg.start      // time in ms from client to server
        ws.send(JSON.stringify(msg))
    })
})