Powerful Rails Features You Might Not Know

This talk was given at Rails World 2023.

If all you've got is a hammer, everything looks like a nail. In tech, there is a constant stream of new features being added every day. Keeping up with the latest Ruby on Rails functionality can help you and your team be far more productive than you might normally be.

In this talk, we walk through a bunch of lesser known or easy to miss features in Ruby on Rails that you can use to improve your skills.

Transcript

1. Chris Oliver Powerful TypeScript Rails Features You Might Not know
2. Learn Your Tools
3. ActiveRecord Excluding User.where.not(id: users.map(&:id)) # SELECT "users".* FROM "users" WHERE "users"."id" NOT IN (1,2) User.all.excluding(users) # SELECT "users".* FROM "users" WHERE "users"."id" NOT IN (1,2)
4. ActiveRecord Strict Loading class Project < ApplicationRecord has_many :comments, strict_loading: true end project = Project.first project.comments ActiveRecord::StrictLoadingViolationError `Project` is marked as strict_loading. The Comment association named `:comments` cannot be lazily loaded.
5. ActiveRecord Strict Loading project = Project.includes(:comments).first Project Load (0.3ms) SELECT "projects".* FROM "projects" ORDER BY "projects"."id" ASC LIMIT ? [["LIMIT", 1]] Comment Load (0.1ms) SELECT "comments".* FROM "comments" WHERE "comments"."project_id" = ? [["project_id", 1]] => #<Project:0x00000001054af780 id: 1> project.comments => [#<Comment:0x00000001054aed80 id: 1, project_id: 1, body: "Hello RailsWorld">]
6. Generated Columns class AddNameVirtualColumnToUsers < ActiveRecord::Migration[7.0] def change add_column :users, :full_name, :virtual, type: :string, as: "first_name || ' ' || last_name", stored: true end end
7. attr_readonly class User < ApplicationRecord attr_readonly :super_admin end
8. with_options class Account < ActiveRecord::Base with_options dependent: :destroy do has_many :customers has_many :products has_many :invoices has_many :expenses end end
9. with_options I18n.with_options locale: user.locale, scope: 'newsletter' do |i18n| subject i18n.t :subject body i18n.t :body, user_name: user.name end
10. Try method_name if respond_to?(:method_name) try(:method_name) try(:method_name) || default (method_name if respond_to?(:method_name)) || default
11. ActionText Embeds
12. Searching Users json.array! @users do |user| json.sgid user.attachable_sgid json.content render( partial: "users/user", locals: {user: user}, formats: [:html] ) end
13. Signed GlobalIDs User.first.attachable_sgid.to_s "eyJfcmFpbHMiOnsibWVzc2FnZSI6IkJBaEpJaDluYVdRNkx5OX FkVzF3YzNSaGNuUXRZWEJ3TDFWelpYSXZNUVk2QmtWVSIsImV4c CI6IjIwMjMtMTAtMjhUMTY6MDY6MTEuMjEyWiIsInB1ciI6ImRl ZmF1bHQifX0=--217284b31bc4e28f6e2cf2890ccee87ca7d3e a2d"
14. ActionText Embeds
15. ActionText Embeds import Trix from "trix" let attachment = new Trix.Attachment({ content: "<div><img src=“…”> Chris Oliver</div>", sgid: "BAh7CEkiCG…" }) element.editor.insertAttachment(attachment)
16. ActionText Embeds <p>Hey <action-text-attachment sgid=“BAh7CEkiCG…"> </action-text-attachment>!</p>
17. Signed GlobalIDs Base64.decode64("eyJfcmFpbHMiOnsibWVzc2FnZSI6IkJBaEpJaDluYVdRNkx5 OXFkVzF3YzNSaGNuUXRZWEJ3TDFWelpYSXZNUVk2QmtWVSIsImV4cCI6IjIwMjMtM TAtMjhUMTY6MD Y6MTEuMjEyWiIsInB1ciI6ImRlZmF1bHQifX0=“) => “{\"_rails\":{\"message\": \"BAhJIh9naWQ6Ly9qdW1wc3RhcnQtYXBwL1VzZXIvMQY6BkVU\",\"exp\": \"2023-10-28T16:06:11.212Z\",\"pur\":\"attachable\"}}"
18. Signed GlobalIDs Base64.decode64(“BAhJIh9naWQ6Ly9qdW1wc3RhcnQtYXBwL1VzZXI vMQY6BkVU") => “\x04\bI\"\x1Fgid://jumpstart-pro/User/1\x06:\x06ET"
19. ActionText Embeds
20. Serialize Coders module ActionText class RichText < Record serialize :body, coder: ActionText::Content end end
21. Serialize Coders class ActionText::Content def self.load(content) new(content) if content end def self.dump(content) case content when nil nil when self content.to_html end end end
22. ActionMailbox Inbound Emails
23. ActionMailbox Inbound Emails # app/mailboxes/application_mailbox.rb class ApplicationMailbox < ActionMailbox::Base routing /@replies\./i => :replies end
24. class RepliesMailbox < ApplicationMailbox MATCHER = /^reply-(\d+)@replies\./ def process conversation.posts.create!( author: author, body: body, message_id: mail.message_id ) end private def conversation Conversation.find(conversation_id) end def conversation_id mail.recipients.find { |recipient| MATCHER.match?(recipient) }[MATCHER, 1] end end ActionMailbox Inbound Emails
25. Routing constraints constraints subdomain: :app do root "dashboard#show" end root "homepage#show"
26. Routing constraints authenticated :user, -> { _1.admin? } do resource :admin end authenticated :user do root "dashboard#show" end root "homepage#show"
27. Routing constraints
28. Draw Routes Rails.application.routes.draw do draw :api # ... end # config/routes/api.rb namespace :api, defaults: {format: :json} do namespace :v1 do resources :accounts end end
29. Custom Generators $ bin/rails g api_client OpenAI --base-url https://api.openai.com
30. Custom Generators $ bin/rails generate generator ApiClient creates an ApiClient generator: lib/generators/api_client/ lib/generators/api_client/api_client_generator.rb lib/generators/api_client/USAGE lib/generators/api_client/templates/ test/lib/generators/api_client_generator_test.rb
31. Custom Turbo Stream Actions
32. Custom Turbo Stream Actions <turbo-stream action="notification" title="Hello world"> </turbo-stream>
33. Custom Turbo Stream Actions # create.turbo_stream.erb <%= turbo_stream_action_tag “notification”, title: “Hello world” %>
34. Custom Turbo Stream Actions import "@hotwired/turbo-rails" Turbo.StreamActions.notification = function() { Notification.requestPermission(function(status) { if (status == "granted") { new Notification(this.getAttribute("title")) } }) }
35. Custom Turbo Stream Actions
36. truncate_words content = 'And they found that many people were sleeping better.' content.truncate_words(5, omission: '... (continued)') # => "And they found that many... (continued)"
37. starts_at > Time.current starts_at.after?(Time.current) starts_at.future? Time Helpers starts_at < Time.current starts_at.before?(Time.current) starts_at.past?
38. Time.current.all_day #=> Fri, 06 Oct 2023 00:00:00 UTC +00:00.. Fri, 06 Oct 2023 23:59:59 UTC +00:00 Time.current.all_week #=> Mon, 02 Oct 2023 00:00:00 UTC +00:00.. Sun, 08 Oct 2023 23:59:59 UTC +00:00 Time.current.all_month #=> Sun, 01 Oct 2023 00:00:00 UTC +00:00.. Tue, 31 Oct 2023 23:59:59 UTC +00:00 Time Helpers
39. 123 -> 123 1234 -> 1,234 10512 -> 10.5K 2300123 -> 2.3M Abbreviated numbers
40. Abbreviated numbers number_to_human(123) # => "123" number_to_human(12345) # => "12.3 Thousand" number_to_human(1234567) # => "1.23 Million" number_to_human(489939, precision: 2) # => "490 Thousand" number_to_human(489939, precision: 4) # => "489.9 Thousand" number_to_human(1234567, precision: 4, significant: false)# => "1.2346 Million"
41. def number_to_social(number) return number_with_delimiter(number) if number < 10_000 number_to_human(number, precision: 1, round_mode: :down, significant: false, format: "%n%u", units: {thousand: "K", million: "M", billion: "B"} ) end Abbreviated numbers
42. Abbreviated numbers number_to_social(123) #=> 123 number_to_social(1_234) #=> 1,234 number_to_social(10_512) #=> 10.5K number_to_social(2_300_123) #=> 2.3M
43. Rails 7.1
44. Rails.env.local? Rails.env.development? || Rails.env.test? Rails.env.local?
45. ActiveSupport Inquiry "production".inquiry.production? # => true "active".inquiry.inactive? # => false
46. Unused routes $ rails routes --unused Found 4 unused routes: Prefix Verb URI Pattern Controller#Action edit_comment GET /comments/:id/edit(.:format) comments#edit PATCH /comments/:id(.:format) comments#update PUT /comments/:id(.:format) comments#update DELETE /comments/:id(.:format) comments#destroy
47. Template strict locals <%# locals: (message:) -%> <%= tag.div id: dom_id(message) do %> <%= message %> <% end %> <%= render partial: “message” %> ArgumentError: missing local: :message <%= render partial: “message”, locals: {message: @message} %>
48. Template strict locals <%# locals: (message: “Hello”) -%> <div> <%= message %> </div> <%= render partial: “message” %> <%= render partial: “message”, locals: {message: “Hey”} %>
49. Template strict locals <%# locals: () -%> <div> Hello RailsWorld! </div> <%= render partial: “message” %>
50. normalizes class User < ApplicationRecord end def email=(value) super value&.strip&.downcase end
51. normalizes class User < ApplicationRecord end normalizes :email, with: ->(email) { email.strip.downcase } normalizes :email, with: ->{ _1.strip.downcase }
52. has_secure_password authenticate_by & password_challenge
53. authenticate_by class User < ApplicationRecord has_secure_password end User.find_by(email: "chris@gorails.com") &.authenticate(“railsworld2023") #=> false or user User.authenticate_by( email: "chris@gorails.com", password: "railsworld2023" ) #=> user or nil
54. password_challenge Current.user.update(password_params) def password_params params.require(:user).permit( :password, :password_confirmation, :password_challenge ).with_defaults(password_challenge: "") end
55. generates_token_for
56. generates_token_for class User < ApplicationRecord generates_token_for :password_reset, expires_in: 15.minutes do # BCrypt salt changes when password is updated BCrypt::Password.new(password_digest).salt[-10..] end end
57. generates_token_for User.find_by_token_for(:password_reset, params[:token]) #=> User or nil user.generate_token_for(:password_reset) “eyJfcmFpbHMiOnsiZGF0YSI6WzkwMjU0MTYzNSwiaC9oTkRJck9uL…”
58. ActiveStorage Variants
59. Named variants class User < ApplicationRecord has_one_attached :avatar do |attachable| attachable.variant :thumbnail, resize_to_limit: [200, 200] end end
60. Preprocessed variants class User < ApplicationRecord has_one_attached :avatar do |attachable| attachable.variant :thumbnail, resize_to_limit: [200, 200], preprocessed: true end end
61. if @project.file.previewable? @project.file.preview(:thumbnail) elsif @project.file.variable? @project.file.variant(:thumbnail) end # Render a preview or variant @project.file.represenation(:thumbnail) Representations
62. Fact L Learn