Rails 3 (beta) Roundup
- 1. Rails 3 (beta) Roundup April 6, 2010
- 2. Why Upgrade • Performance tighter & faster codebase, relational optimizations, shorter path to response, better scaling, better use of Rack & Middleware • Security better routing DSL, XSS protection, more powerful controller stack, better use of Rack & Middleware, fixes • Labour-savings easier routing, reliable gem management, easier Ajax, better code reuse, less monkey-patching, better & easier generators • Modernization Rack reliance, later Ruby, plug in new frameworks and components, new standards • Cost saving lower hardware requirements, less Gem maintenance, consistency means easier for developers
- 3. HTTP://GUIDES.RAILS.INFO/3_0_RELEASE_NOTES.HTML Significant Features • Dependency management with Bundler • More concise router • Chainable database query language • New ActionMailer API • Unobtrusive JavaScript • Better modularity • Improved XSS protection
- 4. Bundler http://railscasts.com/episodes/201-bundler get used to version juggling for now gem "rails", "3.0.0.beta" • all gems listed in # gem "rails", :git => "git://github.com/rails/ Gemfile rails.git" gem "sqlite3-ruby", :require => "sqlite3" • ‘setup’ gemfile # gem "rspec", :group => :test group :test do gem "webrat" end • ‘install’ gem install bundler bundle setup • ‘pack’ bundle install bundle unlock mate Gemfile bundle install --without=test • deploy app bundle pack # application.rb • unlock to modify require 'rails/all' Bundler.require(:default, Rails.env) if defined?(Bundler) Need version 9+. No config.gem required for Rails 3, although some need it for Rails 2.
- 5. New Modular Architecture • “Railties framework is now a set of individual Railties, each inheriting from a new class, Rails::Railtie” • Third-party plugins hook into early stages of initialization • Rake tasks and generators part of the frameworks • “In short, Rails frameworks are now plugins to Rails” Action Mailer * Action Pack * Active Record * Active Resource * Active Model * Active Support • And features like ActiveRecord validations and serialization reusable, eg: include ActiveModel::Validations
- 6. Routing resources :products do • more concise get :detailed, :on => :member end block resources :forums do DSL collection do get :sortable put :sort end resources :topics • rack routes end match "/secret" => "info#about", :constraints => { :user_agent => /Firefox/ } constraints :host => /localhost/ do • constraints match "/secret" => "info#about" match "/topsecret" => "info#about" end match "/hello" => proc { |env| [200, {}, "Hello Rack!"] } • other features root :to => "home#index" match "/about" => "info#about", :as => :about
- 7. Controllers • taller stack abstracting rendering, layouts, rack, AbstractController::Base etc ActionController::Metal • enhance by subclassing New relevant layer ActionController::Base Old • middleware layer ApplicationController • ‘respond_with(@post)’ MyController • flash[:notice] & flash[:alert]
- 8. ActionMailer • like a controller r g mailer UserMailer welcome gives... • email types like actions class UserMailer < ActionMailer::Base def welcome(user, subdomain) @user = user • mail() to send @subdomain = subdomain mail(:from => "admin@testapp.com", :to => @user.email, • no ‘deliver_’ prefix :subject => "Welcome to TestApp") end • mail() do..end for end multipart
- 9. More ActionMailer class UserMailer < ActionMailer::Base default :from => "admin@testapp.com" def welcome(user, subdomain) @user = user @subdomain = subdomain attachments['test.pdf'] = File.read("# {Rails.root}/public/test.pdf") mail(:to => @user.email, :subject => "Welcome to TestApp") do |format| format.html { render 'other_html_welcome' } format.text { render 'other_text_welcome' } end end end
- 10. More ActionMailer class UserMailer < ActionMailer::Base default :from => "admin@testapp.com" def welcome(user, subdomain) @user = user @subdomain = subdomain attachments['test.pdf'] = File.read("# {Rails.root}/public/test.pdf") mail(:to => @user.email, :subject => "Welcome to TestApp") do |format| format.html { render 'other_html_welcome' } format.text { render 'other_text_welcome' } end end end
- 11. Models • New ActiveModel MyClass • Encapsulates ActiveModel::Validations features Serialization ActiveModel::Observing • ‘include’ in non- ActiveModel::Serialization ActiveRecords etc.. • also...
- 12. Find and Scopes • Relational algebra # Article.find(:all, :order => "published_at desc", :limit => 10) Article.order("published_at desc").limit(10) • chained methods # Article.find(:all, :conditions => ["title = ?", ‘This’], :include => :comments) Article.where("title = ?", • named_scope now ‘This’).includes(:comments) scope # Article.find(:first, :order => "published_at desc") Article.order("published_at").last • conditions now # models/active_record.rb scope :visible, where("hidden != ?", true) where scope :published, lambda { where("published_at <= ?", Time.zone.now) } scope :recent, visible.published.order("published_at desc") • deferred retrieval
- 13. ActiveRelation Methods • where • limit • select • joins • order • group • offset • having • includes • lock • readonly • from Book.where(:author => "Austen").include(:versions).order(:title).limit(10) Executed only when the data is needed
- 14. In Views <%= form_for @product do |f| %> • ‘=’ required for all tags <% end %> that output content <%= div_for @product do %> <% end %> including blocks, like <% @comments.each do |c| %> <% end %> ‘form_for’ <% content_for :side do %> <% end %> • ‘-’ no longer required <% cache do %> <% end %> to suppress spaces <!-- products/show.html.erb --> <%= admin_area do %> • write_output_buffer <%= link_to "Edit", edit_product_path(@product) %> | <%= link_to "Destroy", @product, :confirm => "Are you sure?", :method => :delete %> | method in helpers <%= link_to "View All", products_path %> <% end %> # application_helper.rb • no ‘=’ for cache helper def admin_area(&block) content = with_output_buffer(&block) content_tag(:div, content, :class => "admin") end
- 15. XSS Protection • ‘h’ assumed <!-- views/comments/_comment.html.erb --> <div class="comment"> • new ‘raw’ method to %> <%= strong link_to(comment.name, comment.url) unescape <p><%= comment.content %></p> </div> # rails c • html_safe? and "foo".html_safe? safe = "safe".html_safe safe.html_safe? html_safe method to # application_helper.rb check/make string safe def strong(content) "<strong>#{h(content)}</strong>".html_safe end • ‘html_safe’ must be used on helper output
- 16. Unobtrusive Javascript <!-- products/index.html.erb --> <% form_tag products_path, :method => :get, :remote => true do • Makes use of ‘data- %> <p> remote’ tag for Ajax forms <%= text_field_tag :search, params[:search] %> <%= submit_tag "Search", :name => nil %> </p> <% end %> • Other Javascript tag <a href="#" id="alert" data-message="Hello UJS!">Click Here</a> ‘data-’ attributes <%= link_to 'Destroy', post, :method => :delete %> supported In rails.js document.observe("dom:loaded", function() { $(document.body).observe("click", function(event) { • http://github.com/rails/ var message = event.element().readAttribute('data-confirm'); if (message) { jquery-ujs } // ... Do a confirm box var element = event.findElement("a[data-remote=true]"); if (element) { • http://github.com/rails/ // ... Do the AJAX call } var element = event.findElement("a[data-method]"); prototype_legacy_helper if (element) { // ... Create a form } });
- 17. The Commandline • rails s[erver] = start server • rails c = start console • rails g[enerate] = generate Some new rake commands:- • rake db:forward • rake routes CONTROLLER=users
- 18. Generators • All rewritten: http://www.viget.com/extend/rails-3- generators-the-old-faithful • More easily build new templates with Thor: http:// caffeinedd.com/guides/331-making-generators-for- rails-3-with-thor • RAILS_ROOT/lib/templates override generator templates • Rails::Generators::TestCase for testing generators • _form partials and smart labels for form buttons
- 19. Extras • config.filter_parameters << :password • RAILS_ENV, RAILS_ROOT, etc. • redirect_to(@user, :notice => ... ) • ‘validates :login, :presence => true, :length => { :minimum => 4}, :inclusion => { :in => [1, 2, 3] }’
- 20. l18n • I18n faster • I18n on any object • attributes have default translations • Submit tags label automatically • labels pass attribute name
- 21. Before Upgrading... Note: Currently Beta2, so need to be brave/sure/low-impact You will need/want:- • www.railsupgradehandbook.com Jeremy McAnally • http://github.com/rails/rails_upgrade • RVM or other multi-ruby support • Good test coverage (without factory_girl/shoulda?) • Rails 3 hosting • New git branch?
- 22. RVM • Run any version of Ruby in its own environment • Rails 3 needs at least 1.8.7 - Serious bugs in 1.9.1, recommended version 1.9.2 • RVM lets you find best working one for you • Installation instructions at: • http://gist.github.com/296055 • http://railscasts.com/episodes/200-rails-3-beta-and-rvm • no SUDO required
- 23. Update Check plugin • http://github.com/rails/rails_upgrade • Scan for changes to code, etc. • Convert most routes automatically • Create bundler Gemfile • Back up important files • Create starter configuration
- 24. The Rest of the Process www.railsupgradehandbook.com Jeremy McAnally • Regenerate the app • Application.rb & environment.rb • Check and tidy up routes manually • Complete Gemfile manually • Make all tests run • Other Rails 3 enhancements (can be deferred) • Host prepare and deploy (Heroku?)
- 25. Help & thanks • http://www.railsupgradehandbook.com/ by Jeremy McAnally • http://railscasts.com by Ryan Bates • http://guides.rails.info/3_0_release_notes.html • http://www.railsplugins.org/ • http://ruby5.envylabs.com/ • http://blog.envylabs.com/2010/02/rails-3-beautiful-code/ by Greg Pollack • http://weblog.rubyonrails.org/2010/4/1/rails-3-0-second-beta-release