meteor and asynchronous done right !

#4

MeteorAsynchronous done right with Meteor

Agendaintroproblemsolutionoutro

My name is Abderrazak BOUADMA

I’mSoftware Engineer (java)

works at

@mbtdoor linkedIn G+

Thanks to

for their support to Meteor Meetup

intro

Meteor is a platform

built on top of NodeJS

to build cutting edge fast

web applications.

created to Get Things Donelocked free approach

scalable to the infinity … and beyondEmbraces Simplicity

created to Get Things Donelocked free approach

scalable to the infinity … and beyondEmbraces Simplicity

created to Get Things Donelocked free approach

scalable to the infinity … and beyondEmbraces Simplicity

created to Get Things Donelocked free approach

scalable to the infinity … and beyondEmbraces Simplicity

but ...

still have a long way to go.

a problem :(

Event Loop

is a programming construct that waits

for and dispatches events

or messages in a program

http://blog.mixu.net/2011/02/01/understanding-the-node-js-event-loop/

Synchronous !

process fork

threads

single thread

while(new Date().getTime() < now + 1000) { // do nothing}

all I/O is evented and asynchronous

var fs = require('fs');

fs.readFile( __dirname + '/test.txt', function (err, data) {

if (err) {

throw err;

}

console.log(data.toString());

});

loop{db.connect()

conn.query(“select”)

conn.execute(“insert”)

conn.execute(“delete”)

callback pyramid of

a solution :)

Fibershttps://github.com/laverdet/node-fibers

allows us to write asynchronous

code without callbacks

futures

var fs = require('fs');

fs.readFile( __dirname + '/test.txt', function (err, data) {

if (err) {

throw err;

}

});

console.log(data.toString());

var fs = require('fs');

fs.readFile( __dirname + '/test.txt', function (err, data) {

if (err) {

throw err;

}

});

// console.log(data.toString()); won’t run as the ‘data’

// variable is not accessible at this point.

Solutionvar fs = require('fs');

var d;

fs.readFile( __dirname + '/test.txt', function (err, data) {

if (err) {

throw err;

}

d = data;

});

console.log(d.toString());

Resourceshttp://bjouhier.wordpress.com/2012/03/11/fibers-and-threads-in-node-js-what-for/

http://meteorhacks.com/fibers-eventloop-and-meteor.html

http://blog.mixu.net/2011/02/01/understanding-the-node-js-event-loop/

https://github.com/laverdet/node-fibers

Thanks