Introduction to Node.js

Plan

• What is Node.js?
• Frameworks
• Create an app with Express.js
• Example: Tweets
• Pints

Node.js

• JavaScript based software system
• Non-blocking
• Event driven
• Launched in 2009

Blocking VS Non-blocking

Doctor's surgery VS Fast-food outlet

Data I/O

Source: Ryan Dahl 2008 / Jeff Kunkle 2012

JavaScript

What sort of

apps?

Modules

Currently: ~30k modules available

A full Node app

var fs = require('fs');
var contents = fs.readFile(
  './hello.txt',
  'utf8', 
  function(err,contents){
    console.log(contents);
  }
);
console.log("Hello from Node!\n");

Download: http://hop.ie/downloads/node-examples.zip

Hello World

• Create new file: app.js

var http = require('http');

var server = http.createServer(
function (request, response) {
  response.writeHead(
    200,
    {'Content-Type': 'text/plain'}
  );
  response.end('Hello World!\n');
});

server.listen(1337, '127.0.0.1');

Frameworks

• Express.js
• Meteor / Socketstream
• Sails
• Hood.ie

Creating an app

Using Express.js

Example

Tweets

hop.ie/tweets

Source code: github.com/donovanh/tweets

Hosting

• Self hosting
• Appfog
• Heroku
• NodeJitsu

Summary

Next steps

1. Install Node.js
2. Make something
3. ????
4. Debug

Resources

• Ryan Dahl Intro to Node.js
• Node.js Explained
• Tim Caldwell's Intro to Node.js
• Google Group
• NodeJS Dublin Meetup

Thanks

Get in touch

• Twitter: @donovanh
• Email: d@hop.ie

http://hop.ie/go/node