Rails: On Devise sign up page, how to allow (but not require) a user to enter a profile name?

Question

I have a default sign up page generated by Devise, and another that is the landing page for users not signed in.

For both, I would like to allow users to choose a profile name when they sign up, but not require it. How can I do this?

Devise registrations_controller.rb

class Users::RegistrationsController < Devise::RegistrationsController

  def sign_up_params
     params.require(:user).permit(:first_name, :last_name, :email, :email_confirmation, :password, :remember_me)
     [**my attempt:] params.permit(:user).permit(:profile_name) 
  end
end

Answer 1

Take a look at the Rails and Devise example application from the RailsApps project.

Here's how to add a name attribute to the User model. If you don't include a validation validates_presence_of in the model, it will be optional for the user.

First create the migration with a generator.

The migration:

# db/migrate/..._add_name_to_users.rb
class AddNameToUsers < ActiveRecord::Migration
  def change
    add_column :users, :name, :string
  end
end

You need to override the Devise controller to handle strong parameters in Rails 4.0 (and newer).

The controller:

# app/controllers/registrations_controller.rb
class RegistrationsController < Devise::RegistrationsController
  before_filter :update_sanitized_params, if: :devise_controller?

  def update_sanitized_params
    devise_parameter_sanitizer.for(:sign_up) {|u| u.permit(:name, :email, :password, :password_confirmation)}
    devise_parameter_sanitizer.for(:account_update) {|u| u.permit(:name, :email, :password, :password_confirmation, :current_password)}
  end

end

The form:

# app/views/devise/registrations/new.html.erb
<h2>Sign up</h2>

<%= form_for(resource, :as => resource_name, :url => registration_path(resource_name)) do |f| %>
  <%= devise_error_messages! %>
<p><%= f.label :name %><br />
<%= f.text_field :name %></p>

  <div><%= f.label :email %><br />
  <%= f.email_field :email %></div>

  <div><%= f.label :password %><br />
  <%= f.password_field :password %></div>

  <div><%= f.label :password_confirmation %><br />
  <%= f.password_field :password_confirmation %></div>

  <div><%= f.submit "Sign up" %></div>
<% end %>

<%= render "devise/shared/links" %>

Adjust the routes to accommodate the new controller.

The routes:

# config/routes.rb
RailsDevise::Application.routes.draw do
  root :to => "home#index"
  devise_for :users, :controllers => {:registrations => "registrations"}
  resources :users
end