til/rails/scaffold-auth-functionality-with-rails-8-generator.md

Scaffold Auth Functionality With Rails 8 Generator

Rails 8 added a built-in generator for authentication that scaffolds the core models, controllers, views, routes, etc. needed for a basic email/password authentication flow. It creates a User model, if one doesn't already exist, as the authenticated object. It uses the bcrypt gem for password hashing, etc.

Here is an example of what you get when running the generator on a relatively new Rails 8 project:

$ bin/rails generate authentication
      invoke  tailwindcss
      create    app/views/passwords/new.html.erb
      create    app/views/passwords/edit.html.erb
      create    app/views/sessions/new.html.erb
      create  app/models/session.rb
      create  app/models/user.rb
      create  app/models/current.rb
      create  app/controllers/sessions_controller.rb
      create  app/controllers/concerns/authentication.rb
      create  app/controllers/passwords_controller.rb
      create  app/channels/application_cable/connection.rb
      create  app/mailers/passwords_mailer.rb
      create  app/views/passwords_mailer/reset.html.erb
      create  app/views/passwords_mailer/reset.text.erb
      create  test/mailers/previews/passwords_mailer_preview.rb
      insert  app/controllers/application_controller.rb
       route  resources :passwords, param: :token
       route  resource :session
        gsub  Gemfile
      bundle  install --quiet
    generate  migration CreateUsers email_address:string!:uniq password_digest:string! --force
       rails  generate migration CreateUsers email_address:string!:uniq password_digest:string! --force
      invoke  active_record
      create    db/migrate/20250115224625_create_users.rb
    generate  migration CreateSessions user:references ip_address:string user_agent:string --force
       rails  generate migration CreateSessions user:references ip_address:string user_agent:string --force
      invoke  active_record
      create    db/migrate/20250115224626_create_sessions.rb

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