Presentation made on January 2011 about node.js. This technology was used to be the main technology behind the API on "Guia VIVO TV" (codename TVSTAR) with MongoDB.

1. node.js - Eventful JavaScript on the Server
By David Ruiz - @wupsbr
Centro de Inovação do grupo Telefônica Brasil

2. What is node.js?
In a nutshell, it’s JavaScript on
the server side
Created by Ryan Dahl (@ryah) in
2009
Based on the Google V8
JavaScript engine + Evented I/O
Performance is king:
Property access through hidden
classes
Machine code
Garbage collection

3. Want a HTTP Server?
var http = require('http');
http.createServer(function(req, res) {
res.writeHead(200, {'Content-Type': 'text/plain'});
res.end('Welcome to the HTTP Server!');
}).listen(4000);

4. Want a TCP Server?
var tcp = require('net');
tcp.createServer(function(socket) {
socket.addListener('connect', function() {
socket.write('Welcome to the TCP Server!n>');
});
}).listen(4000);

5. Evented I/O benchmarking
APACHE vs NGINX
http://blog.webfaction.com/a-little-holiday-present

6. Evented I/O + V8 Engine
libeio: async I/O
libev: event loop
libuv: wrapper for libev and IOCP
There is a single thread running
No parallel execution... for YOUR code!
db.query().select('*').from('users').execute(function(){
fs.readFile('settings.json', function () {
// Block for five seconds :(
var now = new Date().getTime();
while(new Date().getTime() < now + 5000);
// Response :)
});
});

7. What about multiple cores?
The load balancer approach
:1337
:1338
:1339
The OS approach
var http = require('http'), cluster = require('cluster');
var server = http.createServer(function(req, res) {
res.writeHead(200, {'Content-Type': 'text/plain'});
res.end('TID Rocks!');
});
cluster(server).listen(1337);

8. And about packages?
One line install:
# curl http://npmjs.org/install.sh | sh
Now, let’s install the node.js mysql client?
# npm install mysql

9. And about packages?
One line install:
# curl http://npmjs.org/install.sh | sh
Now, let’s install the node.js mysql client?
There are more than 4900 packages, and more
# npm install mysql
than 15 are added each day!

10. Let’s check the performance
PHP NODE.JS
$a = null; var i, a, b, c, max;
$b = null;
$c = null; max = 1e6;
$i = null;
$max = 1e6; console.time('maths');
$start = microtime(true); for (i = 0; i < max; i++)
{
for ($i = 0; $i < $max; $i++) a = 1234 + 5678 + i;
{ b = 1234 * 5678 + i;
$a = 1234 + 5678 + $i; c = 1234 / 2 + i;
$b = 1234 * 5678 + $i; }
$c = 1234 / 2 + $i;
} console.timeEnd('maths');
var_dump(microtime(true) - $start);
http://www.matt-knight.co.uk/2011/node-js-vs-php-performance-maths/

11. Let’s check the performance
RESULTS IN SECONDS
PHP NODE.JS
$a = null; LOOP SIZE PHP var i, a, b, c, max; NODE.JS
$b = null;
$c = null; max = 1e6;
$i = null;
$max = 1e6; console.time('maths');
100.000 0,077 0,002
$start = microtime(true); for (i = 0; i < max; i++)
{
for ($i = 0; $i < $max; $i++) a = 1234 + 5678 + i;
{ 1.000.000 0,759 b = 1234 * 5678 + 0,016
i;
$a = 1234 + 5678 + $i; c = 1234 / 2 + i;
$b = 1234 * 5678 + $i; }
$c = 1234 / 2 + $i;
} console.timeEnd('maths');
10.000.000 7,605 0,157
var_dump(microtime(true) - $start);
100.000.000 75,159 1,567
http://www.matt-knight.co.uk/2011/node-js-vs-php-performance-maths/

12. Who are using node.js?
linkedin (m.linkedin.com) - mobile stack
The improvements the team saw were staggering. They went from running 15
servers with 15 instances (virtual servers) on each physical machine, to just 4
instances that can handle double the traffic.
http://venturebeat.com/2011/08/16/linkedin-node/
klout (klout.com) - frontend + api
In our tests, a single node.js process was able to handle thousands of
concurrent connections in a very CPU-efficient manner. Plus, using JavaScript
on both the server and the client made writing multi-purpose code very
straightforward. We knew of other companies using node.js at the time, but
most were using it to serve APIs.
http://corp.klout.com/blog/2011/10/the-tech-behind-klout-com/
and many others: HP Yahoo!, Nokia, Heroku, VMWare, Loopt ....
,

13. Test Driven Development!
TEST RESULT

14. Cross platform socket
About Socket.IO Supported languages
Socket.IO aims to make realtime apps Cocoa (iOS)
- fpotter/socketio-cocoa
possible in every browser and mobile Erlang
device, blurring the differences - yrashk/socket.io-erlang
Flash
between the different transport - simb/FlashSocket.IO
mechanisms. It's care-free realtime Go
- madari/go-socket.io (Currently not compatible with 0.7+)
100% in JavaScript. Java
In order to provide realtime connectivity - ibdknox/socket.io-netty
- benkay/java-socket.io.client
on every browser, Socket.IO selects - Ovea/Socket.IO-Java
Lua
the most capable transport at runtime, - ignacio/LuaNode-Socket.IO
without it affecting the API: MrJoes/tornadio (0.6)
- gevent-socketio
WebSocket, Adobe® Flash® Socket, Perl
AJAX long polling, AJAX multipart - vti/pocketio
Python
streaming, Forever Iframe and JSONP - MrJoes/tornadio2 (0.7+)
Polling. Ruby
- markjeee/Socket.IO-rack

15. The node.js ecosystem
Express Cluster
A Sinatra inspired node.js web development Extensible multi-core server management for
framework. nodejs.
Jade Supervisor
Jade is a high performance template engine A little supervisor script for nodejs. It runs
heavily influenced by Haml and implemented your program, and watches for code
with JavaScript for node. changes, so you can have hot-code
Socket.io reloading-ish behavior, without worrying
An simple HTTP Socket interface about memory leaks.
implementation and server. Joyent (http://no.de)
Mongoose Free SmartMachine hosting to delivery
Mongoose aims at solving the complexities modern applications with nodejs.
associated with asynchronous data storage Expresso
by providing a more intuitive API. TDD for nodejs projects in express.
Testosterone
Another and simple TDD for nodejs.

16. great links:
http://nodejs.org/
http://no.de/
http://howtonode.org/
http://jade-lang.com/
http://www.commonjs.org/
https://github.com/ry/node/wiki
http://en.wikipedia.org/wiki/Event_loop
http://lse.sourceforge.net/io/aio.html
http://code.google.com/p/v8/
https://github.com/ry/node/wiki/modules
https://github.com/isaacs/npm

17. thanks!
http://www.davidruiz.eti.br/ http://www.tid.es/
wupsbr@gmail.com @telefonicaid
@wupsbr