Moving forward:
Beyond
the
Object
Paradigm

Disclaimer

This is NOT
NodeJS versus Java
the last super-fancy-coolest-ever fashion

Disclaimer

What can you expect ?
Quick tour of Smart Data
Overview of NodeJS, and related
Feedback on what worked and what failed
...fancy slides
This is about Choosing the right tool for the right job
thank you Mr. Baldwin

Who am I?

Damien Feugas

Worldliner at Lyon since 2006

TUM (4 years)

Java Dojo Hibernate Web 2.0 GoLive! JavaScript Mail Spring AppShop Maven Orange

O&D (1 years)

Massilia Java RequireJS Hibernate Camel Data Publica JavaScript ServiceMix Spring CouchDB Maven jQuery

BSD (1 years)

NodeJS Groovy XWiki MongoDB Backbone JavaScript Smart Data ElasticSearch

What is OOP ?

According to Wikipedia

Object: unit of code

Encapsulation

Class features

And it's very good for ?

Provides structure

Promotes design

Allow reuse

Almost suitable for any situation !

Caution: troll inside

Sometimes, the elegant implementation is just a function. Not a method. Not a class. Not a framework. Just a function. John Carmack
Most software today is very much like an Egyptian pyramid with millions of bricks piled on top of each other, with no structural integrity, but just done by brute force and thousands of slaves. Alan Kay
The problem with object-oriented languages is they've got all this implicit environment that they carry around with them. You wanted a banana but what you got was a gorilla holding the banana and the entire jungle Joe Armstrong

Real example: Smart Data

Objectives regarding data

Collect

Process

Store

Publish

Reuse

Targeted domains

Big data

Cloud Computing

Delivered in SaaS mode

AWL investment program started on Q1 2011

So far so good

It's live !

Many collaborations with other units

PHT

Low Emission Zone
eBourgone
3 commercial proposals

O&D

Connected Vehicules
Machine 2 Machine

RI

Scoring command
Customer Analysis

TUM

Orange's Storm

AtoS Group

Data Lift

BSD

BIPE Analytics

We were enthusiastic Java guys, and used all the good stuff we knew

Spring 2011

Too slow

Too complicated

Too long to test

Too rigid

Too many technologies

So we started over, from the begining

With NodeJS

Summer 2011

What is NodeJS ?

JavaScript on server side

V8 engine

C++ powered, no DOM

Low-level libs

file, net, process...

With Modularity

like imports

Asynchronous and event-based

callbacks

NIO

Single-threaded

no concurrency

NodeJS and its gang

Node Package Manager (NPM)

package.json

central repository

script launcher

Wide range of libraries

48 Web framework

16 DB drivers

61 templating

64 protocols

100+ parsers

72 testers

Forges (Travis) and cloud platforms (Heroku Joyent NodeJitsu)

The Github playground

Almost all is public and free

Real community, real share

Sources are always accessibles

We play also our part

dozens of pullrequests

publication of some libs

var async = require('async');

async.parallel([

  function(callback){
    setTimeout(function(){
      callback(null, 'one');
    }, 200);
  },

  function(callback){
    setTimeout(function(){
      callback(null, 'two');
    }, 100);
  }],

  function(err, results){
    console.dir(results); // [‘one’, ‘two’]
  }
)
    
var http = require('http');

var proxy = http.createClient(80, 'www.google.com');


http.createServer(function(req, resp) {


  var proxyReq = proxy.request(req.method,
      req.url, req.headers);
  req.pipe(proxyReq);



  proxyReq.on('response', function (proxyResp) {
    resp.writeHead(proxyResp.statusCode,
        '', proxyResp.headers)

    proxyResp.pipe(resp);
  });


}).listen(8080);

But... why NodeJS ?

Smart Data is about heterogeneous data

Forget strong-typed languages, and SQL

It's a matter of simplicity

Same language on client and server side

We needed performances

V8 takes 10ms to startup and 10Mo of memory

Asynchronous suits well "many-tiny-requests" needs

Low level and fewer layers is better

Design often changes

Code need to keep simple

Code is often re-written

Does it hurts ?

Start is difficult

Took me a day to understand vows

A brand new language requests some efforts to learn

We rewrote the integration chain at least 3 times

But now it really scales, and it's really fast

We had to make choices

So many libraries.... Which ones suit best our needs ?

Nobody trusts young technologies

You have to be persuasive

Does it worth it ?

Yes, honestly

3000 documents per sec extracted from a CSV

A single server can handle 275 searches per sec

Compiler isn't needed

But you'll have to test everything

ninjas coders neither

We rewrote our 3-month old Java app in 1 month

Trainees can understood the project within weeks

Developpers are happy

They enjoy writing code

They understand what they are doing

Pros

Simplicity
one language for the whole platform
Dynamic
things can evolve freely and quickly
Understandable
you can control anything even in third party libraries
Asynchronous
better use of server resources

Cons

Young
since a year, 3 Node major releases
Dynamic
no compiler. Vigilance, documentation and tests needed
Boilerplate code
too many callbacks. But CoffeeScript helps a lot
Not really OOP
don’t reproduce what you used to do

Java is really a good language

Its good to look somewhere else

Know our needs... and choose the right tool for the right job !

In conclusion