An Introduction to NodeJS

An Introduction to NodeJS

Presented by Carlos Justiniano / HC.JS / @cjus / ver: 1.0.0

About me

• Carlos Justiniano, HC.JS founder and a long-time programmer
• A fullstack developer using NodeJS since 2011
• Developed Node applications in production use
• Developer at MediaMath, note: we're hiring!

Node = NodeJS

So, what is Node?

• "Node.js is an open source, cross-platform runtime environment for server-side and networking applications". - Wikipedia
• A platform for building applications, using JavaScript, for use on and off the net
• An application optimized for performing high speed input/output operations

Node's early beginnings

• Node was created in 2009 by Ryan Dahl which he first published for under Linux
• Ryan debuted Node at the November 2009 European JSConf where it received a standing ovation
• Node's continued development was sponsored by Joyent the company where Ryan worked

Node's popularity

• https://goo.gl/1CPmlS

Who uses Node?

• Google
• Microsoft
• IBM
• SAP
• StrongLoop
• Netflix
• Walmart
• Target

• LinkedIn
• Mozilla
• PayPay
• New York Times
• Fidelity Investments
• Uber

And many many more: https://goo.gl/XvVEoV

Getting started with Node

• Download and Install Node for your machine at: https://nodejs.org/
• Click on the big green Install button

Confirming Node is installed

      $ node --version
      v0.12.7
    

Sample Code!

All of the sample code in this presentation is available on the GitHub repo's subfolder:

• https://github.com/cjus/nodejs-presentation/tree/master/NodeJSProjects

Sample Code: A really simple Node app

Demos:

• Node as a JavaScript execution engine
• A node script can be a one line program
• Super easy to get started using Node

      console.log('Hello future Node developers!');
    

Sample Code: OSInfo

Demos:

• How to write a Node commandline program that accepts arguments
• Calls to the Node process object for querying operating system and environment variables
• Available here: https://github.com/cjus/nodejs-presentation/tree/master/NodeJSProjects/commandline

Sample Code: WordCount

Demos:

• Yet another commandline program
• How to read and process text files using Node
• How to use and write external Node modules
• Available here: https://github.com/cjus/nodejs-presentation/tree/master/NodeJSProjects/commandline

Sample Code: hello using Node

• Demos a simple Node application which responds to a web request with a text message

var http = require('http');
http.createServer(function (req, res) {
  res.writeHead(200, {'Content-Type': 'text/plain'});
  res.end('Hello World\n');
}).listen(1337, '127.0.0.1');
console.log('Server running at http://127.0.0.1:1337/');

Introducing Express

• You can build incredibly powerful networking applications using Node and built-in networking features
• However, as a backend web developer you don't want to write your own version of Apache or Nginx
• Enter web frameworks, such as Express.JS

Building web applications using Node

• Express.JS is a Fast, unopinionated, minimalist web framework for Node.js
• Express is a framework that handles much of the functionality found in web servers
• Available at: http://expressjs.com/

Installing Express

• Because Express is a framework that sits on top of Node, you'll need to make sure you have Node installed.
• Simple instructions here: http://expressjs.com/starter/installing.html

  $ mkdir myapp
  $ cd myapp
  $ npm init
  $ npm install express --save

Sample Code: hello using Express.JS

Demos:

• A simple Node/Express application which responses to a web request with a text message
• Available here: https://github.com/cjus/nodejs-presentation/tree/master/NodeJSProjects/web/simple

var express = require('express')
var app = express();

app.get('/', function(req, res) {
  res.send('Hello World');
});

app.listen(3000);
    

Installing Express Generator

• Express Generator is a Node based commandline program which can generate the basic skeleton of a non-trivial web application
• This saves you from building boilerplate code common to most web server applications you'll build
• Simple instructions here: http://expressjs.com/starter/generator.html

$ mkdir myapp
$ cd myapp
$ npm init
$ npm install express-generator -g

Then you can use express-generator:

$ express myapp

Sample Code: Login

Demos:

• How to build a Node and Express web application
• How to serve web pages and handle RESTFul API calls
• Available here: https://github.com/cjus/nodejs-presentation/tree/master/NodeJSProjects/web

What's next?

• Visit the links in this slide and try the sample apps

The next Node talk will feature:

• Building more advanced Node applications
• A look at NPM - the Node Package Manager
• Building your own Node modules
• Publishing NPM packages
• Extending Node, using C++
• Building a RESTful API server using Node
• Node and Microservices

Contact

• cjus on Twitter and Github
• Email: cjus34@gmail.com
• About: http://cjus.me