Introduction à Ruby

Présentation donnée le 23 février 2012 au Web à Québec 2012 (Québec).

Transcript

1. Introduction à
   Ruby
   Rémi Prévost — Web à Québec 2012
   

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2. Rémi Prévost
   Développeur Web qui aime Ruby
   freelance!
   

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3. Objectif
   

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4. Vous convaincre
   d’essayer Ruby!
   

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5. Simple
   à apprendre
   

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6. Rapide
   à débuter
   

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7. Naturel
   à écrire
   

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8. Sondage
   rapide
   

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9. Ruby, le langage
   Ruby et le Web
   Introduction à Ruby
   

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10. Ruby,
    le langage
    

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11. “I’ve made a
    huge mistake.”
    

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12. Historique
    Installation
    Types de données
    Syntaxe particulière
    Modèle objet
    Gems
    Ruby, le langage
    

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13. Minute
    historique
    

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15. Installer
    Ruby
    

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16. $ ruby -v
    ruby 1.8.7 (2010-01-10 patchlevel 249)
    Mac OS X
    

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17. $ brew install rbenv ruby-build
    $ rbenv install 1.9.2-p290
    Mac OS X
    

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18. $ sudo apt-get install ruby-1.9.1-full
    Ubuntu/Debian
    

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19. Windows
    

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20. $ irb
    ruby-1.9.2-p290 :001 >
    

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21. Hello
    World
    

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22. # Contenu de hello.rb
    puts("Hello World.")
    $ ruby hello.rb
    Hello World.
    

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23. Types de
    données
    

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24. # Fixnum
    7
    # String
    "foo"
    # Array
    [4, 7, 15, 16, 23, 42]
    # Hash
    { :foo => "bar", :omg => 3 }
    

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25. # Symbol
    :foo
    # Regex
    /[a-z]{0,10}\s+$/i
    # Proc
    lambda { |args| return "hello" }
    # NilClass
    nil
    

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26. Syntaxe pensée pour les
    développeurs
    

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27. puts "Hello world."
    # puts("Hello world.")
    puts :foo => :bar, :omg => 3
    # puts({ :foo => :bar, :omg => 3 })
    

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28. nombres = ["un", "deux", "trois"]
    nombres.empty?
    => false
    nombres.first
    => "un"
    nombres.include? "deux"
    => true
    

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29. puts "Hello" if total == 2
    # ou
    if total == 2
    puts "Hello"
    end
    

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30. def hello(name)
    another_method("foo")
    return "Hello, #{name.capitalize}"
    end
    # ou
    def hello(name)
    another_method("foo")
    "Hello, #{name.capitalize}"
    end
    hello("rémi")
    => "Hello, Rémi"
    

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31. [1, 2, 3].map { |x| x * 2 }
    # ou
    [1, 2, 3].map do |x|
    x * 2
    end
    => [2, 4, 6]
    

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32. Modèle objet
    simple
    

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33. Tout est un
    objet
    

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34. Tout?
    

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35. Tout!
    

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36. upcase("foo")
    => NoMethodError: undefined method
    `upcase' for main:Object
    "foo".upcase
    => FOO
    

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37. "foo".upcase
    => "FOO"
    108.to_s
    => "108"
    [1, 2, 3, 4].shuffle
    => [2, 4, 1, 3]
    { :foo => "bar", :omg => 3 }.keys
    => [:foo, :omg]
    

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38. 10.times { |i| puts i }
    0
    1
    2
    3
    4
    5
    6
    7
    8
    9
    

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39. 2 + 3
    # ou
    # 2.+(3)
    => 5
    [1, 2, 3] << 4
    # ou
    # [1, 2, 3].<=> [1, 2, 3, 4]
    

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40. puts "Hello World."
    # Kernel.puts("Hello World.")
    require "../fichier.rb"
    # Kernel.require("../fichier.rb")
    

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41. Définir nos propres
    classes
    

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42. class Article
    end
    article = Article.new
    => #
    

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43. class Article < Contenu
    attr_reader :published
    def initialize(published=true)
    @published = published
    end
    def publish!
    @published = true
    end
    end
    article = Article.new(false)
    article.publish!
    article.published
    => true
    

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44. Modèle objet
    souple
    

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45. Classes
    modifiables
    

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46. class Article
    def delete
    puts "Suppression de l’article!"
    end
    end
    class Article
    def delete
    puts "Finalement, on ne fait rien!"
    end
    end
    article = Article.new
    article.delete
    => "Finalement, on ne fait rien!"
    

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47. class Article
    def delete
    puts "Suppression de l’article!"
    end
    end
    article = Article.new
    class Article
    def delete
    puts "Finalement, on ne fait rien!"
    end
    end
    article.delete
    => "Finalement, on ne fait rien!"
    

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48. Classes internes
    modifiables
    (au runtime!)
    

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49. class String
    def sans_les_voyelles
    self.gsub /[aeiouy]/i, ""
    end
    end
    "webaquebec".sans_les_voyelles
    => "wbqbc"
    

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50. class Fixnum
    def minutes
    self * 60
    end
    def hours
    self * 60.minutes
    end
    end
    2.minutes
    => 120
    5.hours
    => 18000
    

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51. class Object
    def lol!
    "LOL!"
    end
    end
    1.lol!
    => "LOL!"
    "Test".lol!
    => "LOL!"
    [1, 2, 3].lol!
    => "LOL!"
    

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52. class NilClass
    def really?
    "Yep, really!"
    end
    end
    foo = nil
    foo.really?
    => "Yep, really!"
    

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53. Extension via
    modules
    

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54. module SuperModule
    def super!
    "Hé, #{self}, super!"
    end
    end
    class String
    include SuperModule
    end
    "Web à Québec".super!
    => "Hé, Web à Québec, super!"
    

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55. Librairies externes
    centralisées
    

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56. $ ls /var/www/mon-application-php
    wp-atom.php wp-feed.php index.php
    wp-blog-header.php wp-includes/ license.txt
    wp-comments-post.php wp-opml.php wp-login.php
    wp-commentsrss2.php wp-load.php wp-pass.php
    readme.html wp-config.php wp-rdf.php
    wp-activate.php wp-mail.php
    wp-admin/ wp-content/
    wp-app.php wp-cron.php
    $ ls /var/www/mon-application-ruby
    Gemfile Gemfile.lock config.ru app.rb
    

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57. Gems
    (moi je dis « une gem »)
    

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58. $ gem install httparty
    Fetching: multi_xml-0.4.1.gem (100%)
    Fetching: httparty-0.8.1.gem (100%)
    When you HTTParty, you must party hard!
    Successfully installed multi_xml-0.4.1
    Successfully installed httparty-0.8.1
    2 gems installed
    $ irb
    >> HTTParty
    NameError: uninitialized constant Object::HTTParty
    >> require "httparty"
    => true
    >> HTTParty
    => HTTParty
    

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59. $ bundle --version
    command not found: bundle
    $ gem install bundler
    Successfully installed bundler-1.0.22
    1 gem installed
    $ bundle --version
    Bundler version 1.0.22
    

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60. Ruby et le
    Web
    (à Québec)
    

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61. Historique
    Rack
    Frameworks
    • Rails
    • Sinatra
    Hébergement + déploiement
    Ruby et le Web
    

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62. Minute
    historique
    

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63. DHH
    

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64. Rack
    (une structure pour faire du Web)
    

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65. $ tree .
    .
    !"" a-propos.rb
    !"" index.rb
    #"" projets.rb
    0 directories, 3 files
    $ curl http://localhost/index.rb
    Ma page d’accueil!
    $ curl http://localhost/a-propos.rb
    Moi, bla bla bla.
    NOPE
    

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66. Rack
    (une structure pour faire du Web)
    

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67. Interface
    serveur +
    code
    

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68. Utilisateur
    Serveur Web
    Rack
    Ruby
    Rack
    Serveur Web
    Utilisateur
    Requête HTTP
    

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69. # Contenu de config.ru
    class Blogue
    def call(env)
    headers = { "Content-type" => "text/html" }
    [200, headers, "Hello world."]
    end
    end
    run Blogue.new
    

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70. $ gem install rack
    $ rackup config.ru
    WEBrick 1.3.1
    ruby 1.9.2 (2011-07-09)
    WEBrick::HTTPServer#start: pid=69232 port=9292
    $ curl http://localhost:9292
    Hello world.
    $ curl http://localhost:9292/foo/bar
    Hello world.
    

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71. Ruby on
    Rails
    

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72. “Full stack”
    

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73. ORM
    AJAX
    EMAIL
    TESTS
    MVC
    SESSIONS
    CSRF
    ROUTES
    DATABASE
    

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74. “Convention
    over
    configuration”
    

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75. Utilisateur
    Serveur Web
    Rack
    Rails
    Rack
    Serveur Web
    Utilisateur
    Requête HTTP
    Ruby
    

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76. $ rails new mon_application
    …
    $ du --max-depth 1 -h .
    28K ./app
    60K ./config
    4,0K ./db
    4,0K ./doc
    0 ./lib
    0 ./log
    24K ./public
    4,0K ./script
    8,0K ./test
    0 ./tmp
    0 ./vendor
    164K .
    

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77. Ruby on
    Sinatra
    

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78. “Micro-framework”
    

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79. ORM
    AJAX
    EMAIL
    TESTS
    MVC
    SESSIONS
    CSRF
    ROUTES
    DATABASE
    

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80. “Add as you grow”
    

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81. Utilisateur
    Serveur Web
    Rack
    Sinatra
    Rack
    Serveur Web
    Utilisateur
    Requête HTTP
    Ruby
    

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82. Configuration (Bundler)
    Données (DataMapper)
    Routes
    Vues (Haml)
    Sinatra
    

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83. Surprise,
    un blogue!
    

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84. $ tree .
    .
    !"" Gemfile
    !"" config.ru
    #"" blogue.rb
    0 directories, 3 files
    

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85. Configuration
    (avec Bundler)
    

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86. # Contenu de Gemfile
    source "http://rubygems.org"
    gem "sinatra"
    gem "dm-core"
    gem "dm-mysql-adapter"
    gem "dm-migrations"
    gem "haml"
    

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87. # Contenu de Gemfile
    source "http://rubygems.org"
    gem "sinatra", "~> 1.3"
    gem "dm-core"
    gem "dm-mysql-adapter"
    gem "dm-migrations"
    gem "haml", "3.1"
    

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88. $ bundle install
    => Fetching gem metadata from http://rubygems.org/
    Installing addressable (…)
    Installing data_objects (…)
    Installing dm-core (…)
    Installing dm-mysql-adapter (…)
    Installing dm-migrations (…)
    Installing rack (…)
    Installing tilt (…)
    Installing sinatra (…)
    Installing haml (…)
    Using bundler (…)
    Your bundle is complete!
    

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89. # Contenu de config.ru
    require "bundler"
    Bundler.require
    require "./blogue.rb"
    run Sinatra::Application
    

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90. $ rackup config.ru
    WEBrick 1.3.1
    ruby 1.9.2 (2011-07-09)
    WEBrick::HTTPServer#start: pid=69232 port=9292
    

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91. Données
    (avec DataMapper)
    

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92. # Contenu de blogue.rb
    configure do
    DataMapper::Logger.new(STDOUT, :debug)
    DataMapper.setup(:default, "mysql://localhost/blogue")
    end
    class Article
    include DataMapper::Resource # Un module!
    property :id, Serial
    property :title, String
    property :content, Text
    property :created_at, DateTime
    end
    DataMapper.finalize
    DataMapper.auto_upgrade!
    

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93. Article.all
    => [#, #, …]
    Article.all(:created_at.gte => Time.now - 3600)
    => [#]
    Article.get(42)
    => #
    Article.create(:title => "Hello!")
    => #
    Article.all(:title => "Un test").destroy
    => true
    

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94. Routes
    

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95. get "/" do
    …
    end
    post "/articles" do
    …
    end
    put "/articles/:id" do
    …
    end
    delete "/articles/:id" do
    …
    end
    

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96. get "/articles/:id" do
    # params[:id]
    end
    get /\/articles\/(?[0-9]+)/ do
    # params[:id]
    end
    get "/articles/*" do
    # params[:splat]
    end
    get "/articles/:id.?:format?" do
    # params[:id], params[:format]
    end
    

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97. get "/" do
    @articles = Article.all
    end
    get "/articles/:id" do
    @article = Article.get(params[:id])
    end
    

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98. post "/articles" do
    @article = Article.create(params[:article])
    redirect to("/articles/#{@article.id}")
    end
    

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99. $ curl http://localhost:9292/articles
    -X POST
    --data "article[title]=Mon+article"
    --data "article[content]=Le+contenu"
    params
    => {
    :article => {
    :title => "Mon article",
    :content => "Mon contenu"
    }
    }
    

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100. Vues
     (avec Haml)
     

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101. get "/" do
     @articles = Article.all
     end
     get "/articles/:id" do
     @article = Article.find(params[:id])
     end
     

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102. get "/" do
     @articles = Article.all
     "Il y a #{@articles.length} articles."
     end
     get "/articles/:id" do
     @article = Article.get(params[:id])
     "C’est bien #{@article.title}."
     end
     

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103. get "/" do
     @articles = Article.all
     haml :index
     end
     get "/articles/:id" do
     @article = Article.get(params[:id])
     haml :show
     end
     

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104. Introduction à
     Haml
     

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105. %h1 Hello world.
     %p Voici une liste :
     %ul
     %li
     %a{ :href => "http://exomel.com" } Rémi
     Hello world.
     Voici une liste :
     
     
     Rémi
     
     
     

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106. Fin de
     l’introduction à
     Haml
     

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107. -# Contenu de views/index.haml
     %ul
     - @articles.each do |article|
     %li
     %h1= article.title
     = article.content
     

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108. -# Contenu de views/show.haml
     %h1= @article.title
     = @article.content
     

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109. get "/" do
     @articles = Article.all
     haml :index, :layout => :blogue
     end
     get "/articles/:id" do
     @article = Article.get(params[:id])
     haml :show, :layout => :blogue
     end
     

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110. -# Contenu de views/blogue.haml
     !!! 5
     %title Mon blogue
     %body
     = yield
     

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111. -# Exemple de http://localhost/articles/1
     
     Mon blogue
     
     Lorem Ipsum
     Lorem ipsum dolor sit amet, consectetur
     adipiscing elit. Nulla dignissim, libero quis
     dapibus scelerisque
     

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112. Le code final
     

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113. # Contenu de blogue.rb
     configure do
     DataMapper::Logger.new STDOUT, :debug
     DataMapper.setup :default, "mysql://localhost/blogue"
     class Article
     include DataMapper::Resource
     property :id, Serial
     property :title, String
     property :content, Text
     property :created_at, DateTime
     end
     DataMapper.finalize
     DataMapper.auto_upgrade!
     end
     

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114. # Suite de blogue.rb
     get "/" do
     @articles = Article.all
     haml :index, :layout => :blogue
     end
     get "/articles/:id" do
     @article = Article.get(params[:id])
     haml :show, :layout => :blogue
     end
     post "/articles" do
     @article = Article.create(params[:article])
     redirect to("/article/#{@article.id}")
     end
     

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115. -# Contenu de views/index.haml
     %ul
     - @articles.each do |article|
     %li
     %h1= article.title
     = article.content
     -# Contenu de views/show.haml
     %h1= @article.title
     = @article.content
     -# Contenu de views/blogue.haml
     !!! 5
     %title Mon blogue
     %body
     = yield
     

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116. configure do
     DataMapper::Logger.new STDOUT, :debug
     DataMapper.setup :default, "mysql://localhost/blogue"
     class Article
     include DataMapper::Resource
     property :id, Serial
     property :title, String
     property :content, Text
     property :created_at, DateTime
     end
     DataMapper.finalize
     DataMapper.auto_upgrade!
     end
     get "/" do
     @articles = Article.all
     haml :index, :layout => :blogue
     end
     get "/articles/:id" do
     @article = Article.find(params[:id])
     haml :show, :layout => :blogue
     end
     post "/articles" do
     @article = Article.create(params[:article])
     redirect to("/article/#{@article.id}")
     end
     

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117. Hébergement
     et déploiement
     

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118. Le mythe
     (« omg, ruby c’est compliqué! »)
     

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119. Heroku
     (la magie)
     

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120. $ gem install heroku
     $ heroku apps:create blogue
     Creating blogue... done
     Git remote heroku added
     $ git push heroku master
     -----> Heroku receiving push
     -----> Ruby/Rack app detected
     -----> Gemfile detected, running Bundler version 1.0.7
     Unresolved dependencies detected; Installing...
     Your bundle is complete!
     -----> Launching... done, v1
     http://blogue.heroku.com deployed to Heroku
     

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121. mod_passenger
     (la transition idéale)
     

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122. $ sudo gem install passenger
     $ sudo passenger-install-apache2-module
     LoadModule passenger_module /usr/lib/ruby/gems/
     1.9.1/gems/passenger-3.0.11/ext/apache2/
     mod_passenger.so
     PassengerRoot /usr/lib/ruby/gems/1.9.1/gems/
     passenger-3.0.11
     PassengerRuby /usr/bin/ruby1.9.1
     

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123. 
     ServerName blogue.webaquebec.org
     DocumentRoot /var/www/blogue/public
     
     Allow from all
     Options -MultiViews
     
     
     $ cd /var/www/blogue
     $ mkdir public
     $ mkdir tmp
     $ sudo apachectl restart
     

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124. $ touch tmp/restart.txt
     

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125. Résumé
     (en 30 secondes)
     

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126. $ sudo gem install sinatra
     $ cat config.ru
     require "sinatra"
     get "/" do
     "Hello world."
     end
     run Sinatra::Application
     $ rackup config.ru
     WEBrick 1.3.1
     ruby 1.9.2 (2011-07-09)
     WEBrick::HTTPServer#start: pid=69232 port=9292
     

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127. Ressources
     utiles
     

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128. Ressources utiles
     

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129. Ressources utiles
     • sinatrarb.com
     • guides.rubyonrails.org
     • haml-lang.com
     • github.com/explore/languages/ruby
     • heroku.com
     • modrails.com (Apache et nginx)
     

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130. Merci!
     Rémi Prévost — http://exomel.com
     @remi
     

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