Ro r trilogy-part-1

AMIR BARYLKO
THE ROR TRILOGY
A NEW DEV HOPE

Amir Barylko RoR Trilogy Part I: A New Dev Hope

WHO AM I?

• Software quality expert

• Architect

• Developer

• Mentor

• Great cook

• The one who’s entertaining you for the next hour!

RESOURCES

• Email & Twitter: amir@barylko.com, @abarylko

• Slides: http://www.orthocoders.com/presentations

• Company Site: http://www.maventhought.com

• Try Ruby online: http://tryruby.org/

• Learn RoR online: http://railsforzombies.org/


RUBY INTRO
Dynamic languages
Features
Support
Classes
Mixins


DYNAMIC LANGUAGES

• High level

• Dynamically typed

• Runtime over compile time

• Closures

• Reﬂection

• Platform independent

WELCOME TO RUBY

• Created in mid-90s by • Automatic
memory
“Matz” Matsumoto in Japan management

• Smalltalk, Perl inﬂuences • Several
implementations:
MRI, YARB, JRuby
• Dynamic typing
• Totally free!!
• Object Oriented


RUBY FEATURES

• Everything is an expression

• Metaprogramming

• Closures

• Garbage collection

• Exceptions

• Operator overloading, ﬂexible syntax

RUBY SUPPORT

• Hundreds of books

• User conferences all over the world

• Active community (you can create a conference in your own
city and top Ruby coders will go there to teach others, invite
them and see)

• Lots of great web sites: basecamp, twitter, 43 things, hulu,
scribd, slideshare, Justin.tv


CLASSES & OBJECTS

• Initializer and instance variables
class Movie
def initialize(name)
@name = name
end

def play
puts %Q{Playing “#{@name}”. Enjoy!}
end
end

m = Movie.new(“Pulp fiction”)
m.play

=> Playing “Pulp fiction”. Enjoy!


CLASSES & OBJECTS II

• Attributes
class Movie
# attr reader and writer
attr_accesor :name

def initialize(name)
@name = name
end
end

m = Movie.new('Brazil')
m.name = “Pulp fiction”


MIXINS

• One of the greatest Ruby features!

• You can deﬁne functions in Modules, and get them added to
your classes.

• Great code reuse,

• Multiple inheritance alternative.

• Code organization


ENUMERABLE MIXIN

• Quote from the standard library documentation:
...The Enumerable mixin provides
collection classes with several
traversal and searching methods, and
with the ability to sort.
The class must provide a method
each, which yields successive
members of the collection...


ENUMERABLE II

• It provides useful methods such as:

• map

• to_a

• take_while

• count

• inject


MIXIN EXAMPLE

class MovieLibrary
include Enumerable

def each(&block)
contents.each(&block)
end
end


ROR
What is it?
Convention over conﬁguration
Model View Controller
Code generation
Dependency Management
HTML 5 & UJS


WHAT IS ROR?

• Web application development framework

• Created by David Heinemeier Hansson

• With Rails, you would be done by now!

• Open Source & Multi platform

• Very easy to learn

• Comes with everything out of the box!

CONVENTION OVER
CONFIGURATION
• All applications share the same structure

• The application is generated by the rails command

• All the conﬁg ﬁles are ruby code


MODEL VIEW CONTROLLER

• Model: represents the data

• Controllers: Manipulate the data and prepare it to be shown

• View: Shows the data with a particular view engine


CODE GENERATION

• Using rails command:

• Bootstrap: Generates basic structure

• Models: Generated models and tests

• Controllers: Generates controllers, views and tests

• Scaffolds: Generates models, controllers, views, routes,
etc...


DEPENDENCY MANAGEMENT

• Gems are Ruby libraries

• Dependencies are managed with tool gem

• To install a gem just run: gem install xxxxxx

• Bundler is a gem to manage dependencies

• Just create a Gemﬁle and bundler will install all of them


HTML 5 & UNOBTRUSIVE JS

• Supports HTML 5 standards

• data-remote, data-method, data-conﬁg, etc...

• Supports many JS frameworks

• JS code associated to models to handle events, animations, etc

• Coffeescript!


ROR GOODNESS
Common Structure
Automation
Migrations
ActiveRecord
Testing
Scaffolding


COMMON STRUCTURE

• app
• assets: Stylesheets, javascript, images
• controllers: Prepare the data for the views
• helpers: Helper methods to render views
• models: Represent our domain
• views: Templates to be rendered
• each controller has a folder with one
template per method
• layouts:Base templates to surround the views


AUTOMATION

• Rake is a build tool (similar to ant, msbuild, maven)

• Has tasks that can be conﬁgured

• Out of the box has common tasks for database, testing, etc..

• List all the tasks: rake -T

• Very useful to automate tasks and to use in CI servers


MIGRATIONS

• Track the database changes using code

• No need to use SQL

• Upgrades are easy

• Versioning is kept in the database

• Generated automatically when creating models


ACTIVE RECORD

• Relations (ActiveModel)

• Supports multiple databases

• Each table is a class

• All attributes are created dynamically

• Associations are declared by convention

• Each class has CRUD and query operations by default

TESTING OUT OF THE BOX

• Many testing frameworks available

• No additional effort to generate them

• Running them is part of the Rakeﬁle (automation)

• Keep high quality all the way


SCAFFOLDING

• Generated automatically for CRUD operations

• Controllers

• Views

• Tests

• The template used can be replaced of modiﬁed


MOVIE LIBRARY
Demo


TOPICS

• Rails application structure

• Database Migrations

• Using scaffolds

• Model - View - Controllers

• Routing

• Ajax


MORE GOODNESS!
Helpers
Partials
Sass
Routing


HELPERS

• Methods to assist in the view generation

• Reusable

• Associated to each controller

• Testable


PARTIALS

• Templates that can be shared

• Start with underscore “_”

• Can be rendered from views or controllers


SASS

• Quote from sass-lang.com:

Sass is an extension of CSS3, adding
nested rules, variables,
mixins,selector inheritance, and
more.
It’s translated to well-formatted,
standard CSS using the command line
tool or a web-framework plugin.


ROUTING

• Easy to conﬁgure using routes.rb

• Supports REST out of the box

• Easy to restrict actions

• Easy to alias routes

• Allows optional parameters in the routes


RESOURCES II


CLOJURE TRAINING

• When: Nov 6, 7 & 8

• More info: http://www.maventhought.com

• Goal: LearnClojure and functional programming with real
hands on examples


Ro r trilogy-part-1

More Related Content

Viewers also liked

Similar to Ro r trilogy-part-1

More from sdeconf

Recently uploaded

Ro r trilogy-part-1