How to add fields to the Devise registration form

This post will show you how to add custom fields to your Devise registration form in Rails 5. For this example, we'll add a name field.

1. Make sure you've added Devise, generated its views, and migrated your custom fields.

   # generate Devise views
   rails generate devise:views
   
   # add custom fields
   rails g migration AddNameToUsers name:string
   db:migrate
   

2. Add a new controller at app/controllers/registrations_controller.rb. Make sure it inherits from Devise::RegistrationsController, and include your form fields in sign_up_params.

   class RegistrationsController < Devise::RegistrationsController
   
     private
   
       def sign_up_params
         params.require(:user).permit(:email, :password, :name)
       end
   end
   

3. Let's tell Devise to use this controller. In config/routes.rb:

   devise_for :users, :controllers => {
     registrations: 'registrations'
   }
   

4. Add your field to app/views/devise/registrations/new.html.erb.

   <div class="field">
     <%= f.label :name %>
     <%= f.text_field :name %>
   </div>
   

That's all there is to it. You've added a custom field to your Devise registration form. And if you want to allow the user to edit this value too, you can add an account_update_params method to your Registrations Controller and customize app/views/devise/registrations/edit.html.erb.