SO FOLKSSO FOLKS

WANT TOWANT TO

YOUYOU

SO, RUBY IS...SO, RUBY IS...

A dynamic programming language

Focused on simplicity andproductivity

Has an elegant syntax

Natural to read and easy to write

THE IDEALS OF IT’S CREATORTHE IDEALS OF IT’S CREATOR

“ Ruby is simple in appearance, but is verycomplex inside, just like our human body

Yukihiro “Matz” Matsumoto

Ruby is a language of careful balance

Blended of Perl, Smalltalk, Eiffel, Ada, and Lisp

Language that balanced functionalprogramming with imperative programming

RUBY’S GROWTHRUBY’S GROWTH

Released in 1995

Achieved mass acceptance in 2006

Ranked among the top 10 on most of theindices that measure the growth andpopularity of programming languagesworldwide

DEMAND OF RUBYDEMAND OF RUBY

graph by TIOB

E

EVERYTHING IS AN OBJECTEVERYTHING IS AN OBJECT

“ I wanted a scripting language that was more powerfulthan Perl, and more object-oriented than Python

Yukihiro “Matz” Matsumoto

In Ruby, everything is an object

Object-oriented programming calls properties by thename instance variables and actions are known as methods

Ruby follows the influence of the language by giving methods and instancevariables to all of its types

Smalltalk

5.times { print "We *love* Ruby -- it's outrageous!\n" }

RUBY’S FLEXIBILITYRUBY’S FLEXIBILITY

Ruby is seen as a flexible language

It allows its users to freely alter its parts

Essential parts can be removed/redefined, at will

Existing parts can be added upon

Ruby tries not to restrict the coder

class Numeric def plus(x) self.+(x) endend

y = 5.plus 6

Use the readable word plus toRuby’s builtin Numeric class

BUILT WITH RUBYBUILT WITH RUBY AND RAILSAND RAILS

AND NOWAND NOW

WHAT IS RAILS ?WHAT IS RAILS ?

A web application framework written in Ruby

Uses model–view–controller (MVC)

Provides structures for database/web service/pages

JSON or XML for data transfer

Rails emphasizes the use of:

convention over configuration (CoC)

active record pattern

don't repeat yourself (DRY)

A WORD ABOUT ARA WORD ABOUT AR (Active Record)

active record pattern is architectural pattern

This is approach to accessing data in a database

Interface of this pattern would include:

Insert Update Delete

+ properties that correspond to columns inunderlying database table

/ /

SO...SO...In AR database table or view is wrapped into a class

Object instance is tied to a single row in the table

Object created = new row is added to the tableObject updated = row is also updated

Object implements accessor methods for eachcolumn in the table

Object removed = row removed too

C# FELLAS MAY CHECKOUT ACTIVEC# FELLAS MAY CHECKOUT ACTIVERECORD IMPLEMENTATION BY RECORD IMPLEMENTATION BY CASTLECASTLEPROJECTPROJECT::

OKAYOKAYLETS GET IT INSTALLEDLETS GET IT INSTALLED

FOR LINUXFOR LINUX

Or via Ruby Version Manager (RVM)

$ sudo apt-get install ruby-full

$ curl -sSL https://get.rvm.io | bash -s stable$ rvm install ruby$ rvm use ruby --default$ rvm rubygems current

Simply

EASY AS HELL

Finally$ gem install rails

FOR WINDOWSFOR WINDOWS

For God's (and your nerves) sake:

Go to:

Click most inconspicuous button

1.

2.Like this one

AND JUST RUN GODDAMN INSTALLATIONAND JUST RUN GODDAMN INSTALLATION

FINALLYFINALLY

Check all things are installed successfully

$ ruby -vruby 2.0.0p (2015-04-13)

IF SO - WE'RE GOOD TO GO

$ gem -v2.4.8

$ rails -vRails 4.2.3

$ sqlite3 --version3.8.11.1 2015-07-15....

LETS SCAFFOLD !LETS SCAFFOLD !Create new Rails project in folder `blog`

$ rails new blog

Install all dependency gems$ bundle install

$ cd blog

Enter project folder

Run Rails server$ rails server $ rails sor

PROFITPROFIT not yet...

http://localhost:3000

WELCOME ABOARDWELCOME ABOARDFolder Description

/app controllers, models, views and assets for application

/config Application's routes, database, etc.

/db Contains database schema and migrations

/public Static files and compiled assets

/test Unit tests and fixtures

/tmp Cache, pid, and session files

/vendor Place for all third-party code

LETS CLARIFY

DOES RAILS USEWHAT STACK

eRuby

Instead of plain JS

To make CSS debugging even more fun

Templating system similar to ASP, JSP and PHP

Quite unexpected, isn't it ?

&To compile into plain JS

COFFEESCRIPTCOFFEESCRIPTIf you ever wondered how it work

square = (x) -> x * xcube = (x) -> square(x) * x

alert square 2

var cube, square;

square = function(x) { return x * x;};

cube = function(x) { return square(x) * x;};

alert(square(2));

CoffeeScript JavaScript

RAILS CLIRAILS CLIThere are a few commands of everyday usage.

In the order of how much you'll use them are:

rails consolerails serverrakerails generaterails dbconsolerails new app_name

All commands can run with -h or --help to list more information.

GENERATEGENERATE

$ bin/rails generate controller Greetings hello create app/controllers/greetings_controller.rb route get "greetings/hello" invoke erb create app/views/greetings create app/views/greetings/hello.html.erb invoke test_unit create test/controllers/greetings_controller_test.rb invoke helper create app/helpers/greetings_helper.rb invoke assets invoke coffee create app/assets/javascripts/greetings.js.coffee invoke scss create app/assets/stylesheets/greetings.css.scss

WE GET THISWE GET THIS

class GreetingsController < ApplicationController def hello @message = "Hello, how are you today?" endend

app/controllers/greetings_controller.rb

<h1>A Greeting for You!</h1><p><%= @message %></p>

app/views/greetings/hello.html.erb

RAILS `SCAFFOLD`RAILS `SCAFFOLD`

A scaffold in Rails is a full set of:

AS A MORE SUITABLE TOOL FOR GENERATING STUFF

modeldatabase migration for the modelcontroller

FOR EXAMPLEFOR EXAMPLE$ bin/rails generate scaffold HighScore game:string score:integer invoke active_record create db/migrate/20130717151933_create_high_scores.rb create app/models/high_score.rb invoke test_unit create test/models/high_score_test.rb create test/fixtures/high_scores.yml invoke resource_route route resources :high_scores invoke scaffold_controller create app/controllers/high_scores_controller.rb invoke erb create app/views/high_scores create app/views/high_scores/index.html.erb create app/views/high_scores/edit.html.erb create app/views/high_scores/show.html.erb create app/views/high_scores/new.html.erb create app/views/high_scores/_form.html.erb ...

... invoke test_unit create test/controllers/high_scores_controller_test.rb invoke helper create app/helpers/high_scores_helper.rb invoke jbuilder create app/views/high_scores/index.json.jbuilder create app/views/high_scores/show.json.jbuilder invoke assets invoke coffee create app/assets/javascripts/high_scores.js.coffee invoke scss create app/assets/stylesheets/high_scores.css.scss invoke scss identical app/assets/stylesheets/scaffolds.css.scss

AND RAKEAND RAKE

Rake is a Make-like program implemented inRuby.

Except tasks and dependencies arespecified in standard Ruby syntax.

WE USE RAILS FOR:WE USE RAILS FOR:

Running db migrationsSeeding database with preset dataGetting list of all routesRunning test

LETS FIND OUT WHAT WE CAN RAKELETS FIND OUT WHAT WE CAN RAKE

Simply typing:$ bin/rake --tasks

We get:rake about # List versions of all Rails frameworks and the environmentrake assets:clean # Remove old compiled assetsrake assets:clobber # Remove compiled assetsrake assets:precompile # Compile all the assets named in config.assets.precompilerake db:create # Create the database from config/database.yml for the current Rails.env...rake log:clear # Truncates all *.log files in log/ to zero bytesrake middleware # Prints out your Rack middleware stack...rake tmp:clear # Clear session, cache, and socket files from tmp/rake tmp:create # Creates tmp directories for sessions, cache, sockets, and pids

AND THATS ALLAND THATS ALL

CHECKOUT `HELLO WORLD` REPOCHECKOUT `HELLO WORLD` REPO

FURTHER LEARNINGFURTHER LEARNING

RubyRails

GREAT SCREENCASTS:GREAT SCREENCASTS:

https://mackenziechild.me/12-in-12/

THANK YOU !THANK YOU !

QUESTIONS ?QUESTIONS ?