Ams.rb Rails 4 Reality Bites

My Ams.rb slides from 19/03/2013

Transcript

1. Rails 4 Reality Bites Nikolay Petrachkov @nick_jastix nik@jastix.biz 1 Wednesday, March 20, 13
2. About • @ Quintel Intelligence • MSc Business Information Systems @ TU Eindhoven • Diemen resident, yo! 2 Wednesday, March 20, 13
3. Focus • Things to look for during an upgrade 3 Wednesday, March 20, 13
4. bit.ly/ror4map 4 Wednesday, March 20, 13
5. bit.ly/ror4map UPGRADE 5 Wednesday, March 20, 13
6. Prerequisites • Ruby 2.0.0-p0 • Mac OS X 10.7.5 • Rails 3.2 app 6 Wednesday, March 20, 13
7. The Victim • hyfather/reconcileapp • Simple app to manage shared expenses. 7 Wednesday, March 20, 13
8. Gemfile • gem ‘rails’, ‘3.2.12’ • gem ‘rails’, ‘4.0.0.beta1’ • bundle install/update 8 Wednesday, March 20, 13
9. Gemfile Update more gems • gem 'sass-rails', ‘4.0.0.beta1’ • gem 'coffee-rails', ‘4.0.0.beta1’ 9 Wednesday, March 20, 13
10. Your bundle is complete! 10 Wednesday, March 20, 13
11. First Deprecations in config/environments/(development|test).rb • config.whiny_nils is deprecated • config.active_record.auto_explain_threshold_in_seconds removed 11 Wednesday, March 20, 13
12. Devise gem 'devise', git: 'https://github.com/plataformatec/ devise.git', branch: 'rails4' 12 Wednesday, March 20, 13
13. Strong Parameters Temporary solution: • gem ‘protected_attributes’ 13 Wednesday, March 20, 13
14. Strong Parameters class Group < ActiveRecord::Base attr_accessible :description, :name, :users class GroupsController < ApplicationController ............. private def group_params params.require(:group).permit(:description, :name, :users) end end Rails 3 Rails 4 14 Wednesday, March 20, 13
15. Create def create users = group_params.delete(:users) @group = current_user.groups.create(group_params.except(:users)) ...... end 15 Wednesday, March 20, 13
16. • (:users) was a string. • What if it is an array? 16 Wednesday, March 20, 13
17. class ExpensesController < ApplicationController .... private def expense_params params.require(:expense).permit(:amount, :category, users: []) end end 17 Wednesday, March 20, 13
18. What about nested models? 18 Wednesday, March 20, 13
19. class Answer < ActiveRecord::Base belongs_to :question end class Question < ActiveRecord::Base belongs_to :survey has_many :answers accepts_nested_attributes_for :answers, allow_destroy: true end class Survey < ActiveRecord::Base has_many :questions accepts_nested_attributes_for :questions, allow_destroy: true end the example is based on Railscasts #196 19 Wednesday, March 20, 13
20. Wait for it 20 Wednesday, March 20, 13
21. class SurveysController < ApplicationController ......... private def survey_params params.require(:survey).permit(:name, questions_attributes: [ :content, :_destroy, :id, answers_attributes: [:content, :_destroy, :id] ] ) end end 21 Wednesday, March 20, 13
22. Route Matching •root to: “home#index” •match "/about" => "home#about", :as => :about Rails 3 22 Wednesday, March 20, 13
23. Route Matching • root "home#index" • match "/dashboard" => "home#dashboard", as: :dashboard, via: :get • get "/about" => "home#about", as: :about Rails 4 23 Wednesday, March 20, 13
24. Rails Eager Loading in config/environments/*.rb new options: • config.eager_load • config.eager_load_namespaces 24 Wednesday, March 20, 13
25. config.eager_load • true or false • Controls the loading of the whole application into memory. • config.cache_classes = true Rails 3 25 Wednesday, March 20, 13
26. eager_load_namespaces config.eager_load_namespaces << ActionMailer specify which frameworks to load 26 Wednesday, March 20, 13
27. Dynamic Finders •find_or_create_by_email •find_by_name • gem ‘active_record_deprecated_finders’ 27 Wednesday, March 20, 13
28. Dynamic Finders new syntax: • where(name: ‘test’).first_or_create • find_by(name: ‘test’) 28 Wednesday, March 20, 13
29. AR.scope requires lambda: scope :active, -> { where('ended >= ?', Date.today) } 29 Wednesday, March 20, 13
30. before_filter • before_filter • before_action rails does not complain yet 30 Wednesday, March 20, 13
31. Heroku • Add to your Gemfile • ruby ‘2.0.0’ • Success!! 31 Wednesday, March 20, 13
32. Conclusion • Avoid using dynamic finders. Use where. • Add lambdas to scopes. • Strong parameters can be used in Rails 3 via gem. • Prepare for Rails 4! 32 Wednesday, March 20, 13
33. Resources • Devise + Strong parameters: • http://bit.ly/devise4 • Rails 4 mind map: • http://bit.ly/ror4map 33 Wednesday, March 20, 13
34. Thank you! and GOOD LUCK!! 34 Wednesday, March 20, 13