The document discusses the key changes in Rails 4.0. Some of the major new features include strong parameters for mass assignment protection, streaming responses using ActionController::Live, background job handling via ActiveSupport::Queue, and routing concerns to DRY up routes. Some existing features that have been improved include ActiveRecord::Relation to allow chaining of queries, caching with cache digests to automatically invalidate caches, and various performance improvements. A number of older and deprecated features have also been removed.

1. Rails 4.0
Nikola Šantić

2. • MVC Web Framework
• Verzija 1.0 - prosinac 2005.
• “Convention over configuration”, DRY
• Najbolji je
• 235.000 siteova
Ruby on Rails

3. • MVC Web Framework
• Verzija 1.0 - prosinac 2005.
• “Convention over configuration”, DRY
• Najbolji je
• 235.000 siteova
Ruby on Rails

4. • MVC Web Framework
• Verzija 1.0 - prosinac 2005.
• “Convention over configuration”, DRY
• Najbolji je
• 235.000 siteova
Ruby on Rails

5. • MVC Web Framework
• Verzija 1.0 - prosinac 2005.
• “Convention over configuration”, DRY
• Najbolji je
• 235.000 siteova
Ruby on Rails

6. • MVC Web Framework
• Verzija 1.0 - prosinac 2005.
• “Convention over configuration”, DRY
• Najbolji je
• 235.000 siteova
Ruby on Rails

7. Promjene

8. Promjene
verzije commits files changed lines changed
1.2 - 2.0 1,989 1,106
61,774 +
38,554 -
2.3 - 3.0 10,000+ 2,334
131,438 +
106,109 -
3.0 - 3.1 6,818 1,522
74,115 +
62,646 -
3.2 - 4.0? 7,304 2,005
94,231 +
92,069 -

9. Pretpremijera
# Gemfile
# gem 'rails', '3.2.8'
gem 'rails', github: 'rails/rails'
$ bundle update

10. NOVE
STVARI

11. Strong Parameters

12. # app/models/user.rb
class User < ActiveRecord::Base
end
# app/controllers/users_controller.rb
class UsersController < ApplicationController
def update
# params = {user: {name: 'Nikola', age: 25}}
@user = User.find(params[:id])
@user = @user.update_attributes(params[:user])
redirect_to @user
end
end
Mass assignment

13. # app/models/user.rb
class User < ActiveRecord::Base
end
# app/controllers/users_controller.rb
class UsersController < ApplicationController
def update
# params = {user: {name: 'Nikola', admin: true}}
@user = User.find(params[:id])
@user = @user.update_attributes(params[:user])
redirect_to @user
end
end
Mass assignment

14. # app/models/user.rb
class User < ActiveRecord::Base
end
# app/controllers/users_controller.rb
class UsersController < ApplicationController
def update
# params = {user: {name: 'Nikola', admin: true}}
@user = User.find(params[:id])
@user = @user.update_attributes(params[:user])
redirect_to @user
end
end
# @user.admin?
# => true
Mass assignment

15. # app/models/user.rb
class User < ActiveRecord::Base
attr_accessible :name
end
# app/controllers/users_controller.rb
class UsersController < ApplicationController
def update
# params = {user: {name: 'Nikola', admin: true}}
@user = User.find(params[:id])
@user = @user.update_attributes(params[:user])
redirect_to @user
end
end
# @user.admin?
# => false
Mass assignment

16. config.active_record.whitelist_attributes = false

17. # app/models/user.rb
class User < ActiveRecord::Base
end
# app/controllers/users_controller.rb
class UsersController < ApplicationController
def update
# params = {user: {name: 'Nikola', admin: true}}
@user = User.find(params[:id])
@user = @user.update_attributes(user_params)
redirect_to @user
end
private
def user_params
params.require(:user).permit(:name)
end
end
Strong parameters

18. params.require(:user).permit(:name, :email, :password)
Strong parameters

19. params.require(:user).permit(:name, :email, :password)
Strong parameters
POST /users
params = {username: ‘Budala’}

20. params.require(:user).permit(:name, :email, :password)
Strong parameters
POST /users
params = {username: ‘Budala’}
<= 400 Bad Request

21. params.require(:user).permit(:name, :email, :password)
Strong parameters
POST /users
params = {user: {name: ‘Nikola’, admin: true}}

22. params.require(:user).permit(:name, :email, :password)
Strong parameters
POST /users
params = {user: {name: ‘Nikola’, admin: true}}
<= 201 CREATED
User.find_by_name(‘Nikola’).admin?
=> false

23. # app/controllers/users_controller.rb
class UsersController < ApplicationController
def user_params
params.require(:user).permit(:name)
end
end
# app/controllers/admin/users_controller.rb
class Admin::UsersController < ApplicationController
def user_params
params.require(:user).permit(User.attribute_names)
end
end
Višestruke uloge

24. https://github.com/rails/strong_parameters
Dostupan već danas!

25. ActiveSupport::Queue

26. • delayed_job
• Resque
• Sidekiq
• ...
Background job - Prije

27. class ExpensiveOperation
def run
# ...
end
end
Rails.queue.push(ExpensiveOperation.new)
Background job - Sada

28. config.queue = :asynchronous
config.queue = :synchronous
config.queue = :resque
Podešavanje

29. config.action_mailer.async = true
Asinkroni ActionMailer

30. ActionController::Live

31. class MyController < ActionController::Base
def index
100.times {
response.stream.write "hello worldn"
}
response.stream.close
end
end
Streaming

32. class MyController < ActionController::Base
include ActionController::Live
def index
100.times {
response.stream.write "hello worldn"
}
response.stream.close
end
end
Streaming

33. class MyController < ActionController::Base
include ActionController::Live
def index
100.times {
response.stream.write "hello worldn"
}
response.stream.close
end
end
Streaming
WEBrick

34. class MyController < ActionController::Base
include ActionController::Live
def index
100.times {
response.stream.write "hello worldn"
}
response.stream.close
end
end
Streaming
WEBrick

35. class MyController < ActionController::Base
include ActionController::Live
def index
100.times {
response.stream.write "hello worldn"
}
response.stream.close
end
end
Streaming
WEBrick Unicorn

36. class MyController < ActionController::Base
include ActionController::Live
def index
100.times {
response.stream.write "hello worldn"
}
response.stream.close
end
end
Streaming
WEBrick Unicorn

37. class MyController < ActionController::Base
include ActionController::Live
def index
100.times {
response.stream.write "hello worldn"
}
response.stream.close
end
end
Streaming
WEBrick Unicorn
Rainbows
Puma
Thin

38. Rails 4.0 > Node.js ?

39. STARE
STVARI

40. Cache Digest

41. @user
Babuška caching
@project
@project
@task
@task
@task

42. <%# app/views/users/show.html.erb %>
<% cache [ 'v1', @user ] do %>
<h1> <%= @user.name %> </h1>
<%= render @user.projects %>
<% end %>
<%# app/views/projects/_project.html.erb %>
<% cache [ 'v1', project ] do %>
<%= project.description %>
<%= render project.tasks %>
<% end %>
<%# app/views/tasks/_task.html.erb %>
<% cache [ 'v1', task ] do %>
Todo: <%= task.content %>
<% end %>
Babuška caching

43. <%# app/views/users/show.html.erb %>
<% cache [ 'v1', @user ] do %>
<h1> <%= @user.name %> </h1>
<p> Vaši projekti: </p>
<%= render @user.projects %>
<% end %>
<%# app/views/projects/_project.html.erb %>
<% cache [ 'v1', project ] do %>
<%= project.description %>
<%= render project.tasks %>
<% end %>
<%# app/views/tasks/_task.html.erb %>
<% cache [ 'v1', task ] do %>
Todo: <%= task.content %>
<% end %>
Babuška caching

44. <%# app/views/users/show.html.erb %>
<% cache [ 'v2', @user ] do %>
<h1> <%= @user.name %> </h1>
<p> Vaši projekti: </p>
<%= render @user.projects %>
<% end %>
<%# app/views/projects/_project.html.erb %>
<% cache [ 'v1', project ] do %>
<%= project.description %>
<%= render project.tasks %>
<% end %>
<%# app/views/tasks/_task.html.erb %>
<% cache [ 'v1', task ] do %>
Todo: <%= task.content %>
<% end %>
Babuška caching

45. <%# app/views/users/show.html.erb %>
<% cache [ 'v2', @user ] do %>
<h1> <%= @user.name %> </h1>
<p> Vaši projekti: </p>
<%= render @user.projects %>
<% end %>
<%# app/views/projects/_project.html.erb %>
<% cache [ 'v1', project ] do %>
<%= project.description %>
<%= render project.tasks %>
<% end %>
<%# app/views/tasks/_task.html.erb %>
<% cache [ 'v1', task ] do %>
Todo: <%= task.content %>
Date: <%= task.date %>
<% end %>
Babuška caching

46. <%# app/views/users/show.html.erb %>
<% cache [ 'v3', @user ] do %>
<h1> <%= @user.name %> </h1>
<p> Vaši projekti: </p>
<%= render @user.projects %>
<% end %>
<%# app/views/projects/_project.html.erb %>
<% cache [ 'v2', project ] do %>
<%= project.description %>
<%= render project.tasks %>
<% end %>
<%# app/views/tasks/_task.html.erb %>
<% cache [ 'v2', task ] do %>
Todo: <%= task.content %>
Date: <%= task.date %>
<% end %>
Babuška caching

47. <%# app/views/users/show.html.erb %>
<% cache @user do %>
<h1> <%= @user.name %> </h1>
<%= render @user.projects %>
<% end %>
<%# app/views/projects/_project.html.erb %>
<% cache project do %>
<%= project.description %>
<%= render project.tasks %>
<% end %>
<%# app/views/tasks/_task.html.erb %>
<% cache task do %>
Todo: <%= task.content %>
<% end %>
Sada

48. Čarolijom!
(+ koristi MD5 templatea i partiala
kao cache key)
Kako???

49. https://github.com/rails/cache_digests
Dostupan već danas!

50. Routing concerns

51. BCX::Application.routes.draw do
resources :messages { resources :comments }
resources :forwards { resources :comments }
resources :uploads { resources :comments }
end
Prije

52. BCX::Application.routes.draw do
concern :commentable do
resources :comments
end
resources :messages, :forwards, :uploads, concerns: :commentable
end
Sada

53. https://github.com/rails/routing_concerns
Dostupan već danas!

54. ActiveRecord::Relation

55. User.first
User.last
Prvi koji?

56. User.first
User.last
Prvi koji?
Sortirani po id-u
SELECT "users".* FROM "users" ORDER BY id LIMIT 1

57. Koji svi?
User.all
Vraća ActiveRecord::Relation objekt

58. Koji svi?
User.all
Vraća ActiveRecord::Relation objekt
@users = User.all
@users = @users.where(name: params[:name]) if params[:name]
@users = @users.order(params[:sort_by]) if params[:sort_by]

59. Nikoji, eto koji
User.none
Null objekt koji se dalje može ulančavati

60. I još
User.(metoda)!

61. I još
User.(metoda)!
@users = User.all
@users = @users.where(name: params[:name]) if params[:name]
@users = @users.order(params[:sort_by]) if params[:sort_by]
Prije:

62. I još
User.(metoda)!
@users = User.all
@users = @users.where(name: params[:name]) if params[:name]
@users = @users.order(params[:sort_by]) if params[:sort_by]
Prije:
@users = User.all
@users.where!(name: params[:name]) if params[:name]
@users.order!(params[:sort_by]) if params[:sort_by]
Sada:

63. ZBOGOM
STVARI

64. Zbogom Ruby 1.8

65. Zbogom
find(:all, :conditions => ...)

66. Zbogom
ActiveRecord:SessionStore

67. Zbogom
ActiveResource

68. Zbogom
Rails::Plugin

69. Zbogom
Rails::Plugin
• u /lib folder
• pretvori u gem

70. • Turbolinks
• Cached schema dump
• HTTP PATCH
• HTML5 helperi
• config.threadsafe!
Još STO stvari

71. • Rails 3.1 - gotov
• Rails 3.2 - neka deprecation upozorenja, podrška do 4.1
• Rails 4.0 - deprecation upozorenja
• Rails 4.1 - uklanjanje deprecated dijelova
Verzioniranje

72. Kad izlazi?

73. http://edgeguides.rubyonrails.org/4_0_release_notes.html
Dodatna literatura

74. Rails 4.0 Mind map
Boston.rb - What to expect in Rails 4.0
EdgeRails.info Blog
https://github.com/rails/rails
Dodatna dodatna literatura

75. Pitanja?

76. Hvala na pažnji!