convince bosses and clients

Today's topics

1. What is Node.js ?
2. Is there any success story ?
3. Making the good choices when starting a project

Vladimir de Turckheim

• Software engineer @ Steamulo
• Former cyber-security consultant
• JavaScript full stack engineer
• DevOps
• Open-Source contributor

What is Node.js ?

A brief history of Node.js

• Created in 2009
• Used to be sponsored by Joyent
• 2011: NPM  is introduced
• DEC 2014: a fork (iojs) is created due to internal conflicts
• JUN 2015 creation of the Node.js fundation
• SEP 2015 iojs and Node.js are merged in Node.js 4

Version support

NPM

• NPM is the package manager for Node.js
• It is now also used for managing dependencies in most modern JavaScript applications
• npmjs.com is the most popular module repository in the world

The event loop

from softwareengineeringdaily.com

Asynchronous programming

'use strict';

// CommonJS import syntax
// 'http' is a standard library
var http = require('http');

// pseudo database
var database = require('fake-database');

var server = http.createServer((request, response) => { 

    // each time a connection is made, this function is called

    // decorate response with header
    response.writeHead(200, {'Content-Type': 'text/plain'}); 

    // add content and end process
    database.getData((err, result) => {

        response.end(result); 
        // The call of `response.end` signals that the callback treatment is done
    });

});

server.listen(3000);

console.log('Server listenning on http://localhost:3000');

Asynchronous programming II

'use strict';

setTimeout(() => {

        console.log('hello');
}, 1000);

console.log('world');

results in

Is there any success story ?

Paypal

Compared to the same application in Java:

• Built almost twice as fast with fewer people

• Written in 33% fewer lines of code and 40% fewer files

• Double the requests per seconds

• 35% decrease in the average response time

source: paypal-engineering.com

Node.js reduces development costs !

Wallmart

• All black Friday mobile traffic is handled by Node.js
• Servers did not go over 1% CPU
• Team deployed a new version while 200,000,000 users were online

LinkedIn

• Mobile traffic is handled by Node.js servers
• Went from 30 servers to 3
• Application is 20 times faster

Some big Node.js adopter

Making the good choices when starting a project

Use if you want

• intensive I/O
• real time features
• scalability
• a rich module ecosystem (NPM)
• to build API
• to build streaming applications

Don't use if you want

• intensive CPU tasks
• to employ developers who are not used to produce elegant and maintainable code
• to employ developers who are not able to understand asynchronous systems

To node or not to node ?

framework ?

• Express is still popular but might not be relevant anymore
• hapijs is a popular high level framework with modern concepts and security features
• Koa is closer to Node.js native API

So if you want to build with stability, security, and structure in mind, i would personally recommend hapijs. On the other hand, if you want to learn everything, build piece by piece, and code closer to node-core, I’d recommend Koa.

Jonathan Ong, Koa developer

tools ?

• No need for babel, traceur or TypeScript: Node.js ES6 is enough
• Need a good test runner and assertion library
• Code style enforcement has to be done

Production ?

• Node.js can run as a service
• There is process managers for Node.js
• Hide your Node.js server behind a reverse proxy that will handle TLS or other CPU demanding tasks