Multiple user models with Ruby On Rails and devise to have separate registration routes but one common login route

Okay, so I worked it through and came to the following solution.
I needed to costumize devise a little bit, but it's not that complicated.

The User model

# user.rb
class User < ActiveRecord::Base
  devise :database_authenticatable, :registerable,
         :recoverable, :rememberable, :trackable, :validatable

  attr_accessible :email, :password, :password_confirmation, :remember_me

  belongs_to :rolable, :polymorphic => true
end

The Customer model

# customer.rb
class Customer < ActiveRecord::Base
  has_one :user, :as => :rolable
end

The Designer model

# designer.rb
class Designer < ActiveRecord::Base
  has_one :user, :as => :rolable
end

So the User model has a simple polymorphic association, defining if it's a Customer or a Designer.
The next thing I had to do was to generate the devise views with rails g devise:views to be part of my application. Since I only needed the registration to be customized I kept the app/views/devise/registrations folder only and removed the rest.

Then I customized the registrations view for new registrations, which can be found in app/views/devise/registrations/new.html.erb after you generated them.

<h2>Sign up</h2>

<%
  # customized code begin

  params[:user][:user_type] ||= 'customer'

  if ["customer", "designer"].include? params[:user][:user_type].downcase
    child_class_name = params[:user][:user_type].downcase.camelize
    user_type = params[:user][:user_type].downcase
  else
    child_class_name = "Customer"
    user_type = "customer"
  end

  resource.rolable = child_class_name.constantize.new if resource.rolable.nil?

  # customized code end
%>

<%= form_for(resource, :as => resource_name, :url => registration_path(resource_name)) do |f| %>
  <%= my_devise_error_messages!    # customized code %>

  <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>

  <% # customized code begin %>
  <%= fields_for resource.rolable do |rf| %>
    <% render :partial => "#{child_class_name.underscore}_fields", :locals => { :f => rf } %>
  <% end %>

  <%= hidden_field :user, :user_type, :value => user_type %>
  <% # customized code end %>

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

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

For each User type I created a separate partial with the custom fields for that specific User type, i.e. Designer --> _designer_fields.html

<div><%= f.label :label_name %><br />
<%= f.text_field :label_name %></div>

Then I setup the routes for devise to use the custom controller on registrations

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

Then I generated a controller to handle the customized registration process, copied the original source code from the create method in the Devise::RegistrationsController and modified it to work my way (don't forget to move your view files to the appropriate folder, in my case app/views/user_registrations

class UserRegistrationsController < Devise::RegistrationsController
  def create
    build_resource

    # customized code begin

    # crate a new child instance depending on the given user type
    child_class = params[:user][:user_type].camelize.constantize
    resource.rolable = child_class.new(params[child_class.to_s.underscore.to_sym])

    # first check if child instance is valid
    # cause if so and the parent instance is valid as well
    # it's all being saved at once
    valid = resource.valid?
    valid = resource.rolable.valid? && valid

    # customized code end

    if valid && resource.save    # customized code
      if resource.active_for_authentication?
        set_flash_message :notice, :signed_up if is_navigational_format?
        sign_in(resource_name, resource)
        respond_with resource, :location => redirect_location(resource_name, resource)
      else
        set_flash_message :notice, :inactive_signed_up, :reason => inactive_reason(resource) if is_navigational_format?
        expire_session_data_after_sign_in!
        respond_with resource, :location => after_inactive_sign_up_path_for(resource)
      end
    else
      clean_up_passwords(resource)
      respond_with_navigational(resource) { render_with_scope :new }
    end
  end
end

What this all basically does is that the controller determines which user type must be created according to the user_type parameter that's delivered to the controller's create method by the hidden field in the view which uses the parameter by a simple GET-param in the URL.

For example:
If you go to /users/sign_up?user[user_type]=designer you can create a Designer.
If you go to /users/sign_up?user[user_type]=customer you can create a Customer.

The my_devise_error_messages! method is a helper method which also handles validation errors in the associative model, based on the original devise_error_messages! method

module ApplicationHelper
  def my_devise_error_messages!
    return "" if resource.errors.empty? && resource.rolable.errors.empty?

    messages = rolable_messages = ""

    if !resource.errors.empty?
      messages = resource.errors.full_messages.map { |msg| content_tag(:li, msg) }.join
    end

    if !resource.rolable.errors.empty?
      rolable_messages = resource.rolable.errors.full_messages.map { |msg| content_tag(:li, msg) }.join
    end

    messages = messages + rolable_messages   
    sentence = I18n.t("errors.messages.not_saved",
                      :count => resource.errors.count + resource.rolable.errors.count,
                      :resource => resource.class.model_name.human.downcase)

    html = <<-HTML
    <div id="error_explanation">
    <h2>#{sentence}</h2>
    <ul>#{messages}</ul>
    </div>
    HTML

    html.html_safe
  end
end

UPDATE:

To be able to support routes like /designer/sign_up and /customer/sign_up you can do the following in your routes file:

# routes.rb
match 'designer/sign_up' => 'user_registrations#new', :user => { :user_type => 'designer' }
match 'customer/sign_up' => 'user_registrations#new', :user => { :user_type => 'customer' }

Any parameter that's not used in the routes syntax internally gets passed to the params hash. So :user gets passed to the params hash.

So... that's it. With a little tweeking here and there I got it working in a quite general way, that's easily extensible with many other User models sharing a common User table.

Hope someone finds it useful.


I didn't manage to find any way of commenting for the accepted answer, so I'm just gonna write here.

There are a couple of things that don't work exactly as the accepted answer states, probably because it is out of date.

Anyway, some of the things that I had to work out myself:

  1. For the UserRegistrationsController, render_with_scope doesn't exist any more, just use render :new
  2. The first line in the create function, again in the UserRegistrationsController doesn't work as stated. Just try using

    # Getting the user type that is send through a hidden field in the registration form.
    user_type = params[:user][:user_type]
    
    # Deleting the user_type from the params hash, won't work without this.
    params[:user].delete(:user_type)
    
    # Building the user, I assume.
    build_resource
    

instead of simply build_resource. Some mass-assignment error was coming up when unchanged.

  1. If you want to have all the user information in Devise's current_user method, make these modifications:

class ApplicationController < ActionController::Base protect_from_forgery

  # Overriding the Devise current_user method
  alias_method :devise_current_user, :current_user
  def current_user
    # It will now return either a Company or a Customer, instead of the plain User.
    super.rolable
  end
end


I was following the above instructions and found out some gaps and that instructions were just out of date when I was implementing it.

So after struggling with it the whole day, let me share with you what worked for me - and hopefully it will save you few hours of sweat and tears

  • First of all, if you are not that familiar with RoR polymorphism, please go over this guide: http://astockwell.com/blog/2014/03/polymorphic-associations-in-rails-4-devise/ After following it you will have devise and user users models installed and you will be able to start working.

  • After that please follow Vapire's great tutorial for generating the views with all the partails.

  • What I found most frustrating was that dut to using the latest version of Devise (3.5.1), RegistrationController refused to work. Here is the code that will make it work again:

    def create 
    
      meta_type = params[:user][:meta_type]
      meta_type_params = params[:user][meta_type]
    
      params[:user].delete(:meta_type)
      params[:user].delete(meta_type)
    
      build_resource(sign_up_params)
    
      child_class = meta_type.camelize.constantize
      child_class.new(params[child_class.to_s.underscore.to_sym])
      resource.meta = child_class.new(meta_type_params)
    
      # first check if child intance is valid
      # cause if so and the parent instance is valid as well
      # it's all being saved at once
      valid = resource.valid?
      valid = resource.meta.valid? && valid
    
      # customized code end
      if valid && resource.save    # customized code
        yield resource if block_given?
        if resource.persisted?
          if resource.active_for_authentication?
            set_flash_message :notice, :signed_up if is_flashing_format?
            sign_up(resource_name, resource)
            respond_with resource, location: after_sign_up_path_for(resource)
          else
            set_flash_message :notice, :"signed_up_but_#{resource.inactive_message}" if is_flashing_format?
            expire_data_after_sign_in!
            respond_with resource, location: after_inactive_sign_up_path_for(resource)
          end
        else
          clean_up_passwords resource
          set_minimum_password_length
          respond_with resource
        end
      end
    end
    
  • and also add these overrides so that the redirections will work fine:

    protected
    
      def after_sign_up_path_for(resource)
        after_sign_in_path_for(resource)
      end
    
      def after_update_path_for(resource)
        case resource
        when :user, User
          resource.meta? ? another_path : root_path
        else
          super
        end
      end
    
  • In order that devise flash messages will keep working you'll need to update config/locales/devise.en.yml instead of the overridden RegistraionsControlloer by UserRegistraionsControlloer all you'll need to do is add this new section:

    user_registrations:
      signed_up: 'Welcome! You have signed up successfully.'
    

Hope that will save you guys few hours.