Grégory Houllier ghoullier

Alex's Rails Cheat Sheet

I think the most confusing thing that I have found about Ruby on Rails so far has been the transition from (trying to) write code myself to the use of the fabled "Rails Magic". So, to help my own understanding of a few core Ruby on Rails concepts, I have decided to write something on what I think is a CRITICAL topic... the idea of Convention over Configuration and why (in my mind) it is the most important thing that helps Rails become magic!

(This may be a topic that we cover in more detail in class but as I said, I'm writing this for my own understanding... I hope it helps someone else understand things too... Perhaps you can give me a hand when I'm crying next week!)

##Convention over configuration ###What does this "actually" mean...

The introduction to Reactive Programming you've been missing

(by @andrestaltz)

This tutorial as a series of videos

If you prefer to watch video tutorials with live-coding, then check out this series I recorded with the same contents as in this article: Egghead.io - Introduction to Reactive Programming.

Mobile Server Side Rendering

This year marks the first year that we are doing full scale rendering of our SPA application on our mobile.walmart.com Node.js tier, which has provided a number of challenges that are very different from the mostly IO-bound load of our prior #nodebf.

The infrastructure outlined for last year is the same but our Home, Item and a few other pages are prerendered on the server using fruit-loops and hula-hoop to execute an optimized version of our client-side JavaScript and provide a SEO and first-load friendly version of the site.

To support the additional CPU load concerns as peak, which we hope will be unfounded or mitigated by our work, we have also taken a variety of steps to increase cache lifetimes of the pages that are being served in this manner. In order of their impact:

Event Loop Management

React

A JavaScript library that manages the UI.

What does it do?

React enables you to express in a declarative way what your UI should look like at any point in time; while building your app with little, reusable blocks: components.

UI development as a first-class citizen

The single hardest part of front-end development at scale is making changes to code and understanding all of the visual and behavioral effects that will occur as a result.

When you build a component, tests should be written that expose each state a component can be in. This test should generate a static html file and a corresponding image for every discrete state a component can be in.

Angular2 + JSPM cheat sheet

First time setup

install jspm beta: npm install -g jspm@beta
set up your project: jspm init
install dependencies: jspm install angular2 reflect-metadata zone.js es6-shim

This will create a jspm_packages folder, and a config.js file.

Open the config.js file - this file manages options for the System.js loader - tweak it as appropriate

	describe('Mon test', function() {

	var scope, maFactory;

	// Charge ton module à tester
	beforeEach(module('monModuleATester'));

	// Inject ce que tu as besoin
	// inject() est obligatoire, c'est direct ngMOck
	beforeEach(inject(function ($rootScope, $injector) {

	// ES6 tl;dr; for beginners

	// 1. variables

	// `const` & `let` are scoped at the block level
	if(true) {
	let foo = "bar"
	}
	foo // ReferenceError

	function mapValues(obj, fn) {
	return Object.keys(obj).reduce((result, key) => {
	result[key] = fn(obj[key], key);
	return result;
	}, {});
	}

	function pick(obj, fn) {
	return Object.keys(obj).reduce((result, key) => {
	if (fn(obj[key])) {

	function logClass(target: any) {

	// save a reference to the original constructor
	var original = target;

	// a utility function to generate instances of a class
	function construct(constructor, args) {
	var c : any = function () {
	return constructor.apply(this, args);
	}