active_record-acts_as and devise integration - ruby-on-rails

Question

i'm writing my first rails application using active_record-acts_as and devise. I have an User (devise authentication and actable) , Client (act_as) and Owner (act_as).I overrided the registration_controller to add some extra fields in the devise form, fields like name, surname etc. that i need for Client and Owner. I'm trying to sign up both Client and Owner using the devise authentication of the User but adding other fields. I thought to define the authentication on the User to avoid duplicates in the schema. Is it possible to do this without define the devise controller of both Client and Owner?
client.rb
class Client < ActiveRecord::Base
acts_as :user
end
owner.rb
class Owner < ActiveRecord::Base
acts_as :user
end
user.rb
class Utente < ActiveRecord::Base
actable
# Include default devise modules. Others available are:
# :confirmable, :lockable, :timeoutable and :omniauthable
devise :database_authenticatable, :registerable,
:recoverable, :rememberable, :trackable, :validatable
end
routes.rb
Rails.application.routes.draw do
devise_for :users, :controllers => { registrations: 'registrations' }
resources :clients
resources :users
resources :owners
end

Answer 1

I think what you should understand about the gem you are using is that, it buys you the idea of having empty columns. However it is necessary you note that, each details goes to its respective table.
Having said that, you can use rails authentication on any table where you hope to set authentication on.
Now based on the later part of your question, where you asked to avoid duplicates on your table, you set validation in your model, such that any of your model becomes:
class Utente < ActiveRecord::Base
actable
# Include default devise modules. Others available are:
# :confirmable, :lockable, :timeoutable and :omniauthable
devise :database_authenticatable, :registerable,
:recoverable, :rememberable, :trackable, :validatable
validates :email, :uniqueness => true
end
You could see documentation of how you set validations on active_record-acts_as here
Since its MTI with Devise, respective data goes to where it's suppose to be right out of the box, then I will suggest you set validations on other tables that acts_as :user, but on attributes that are not on the actable devise table. For example:
class Client < ActiveRecord::Base
acts_as :user
validates :school, :uniqueness => true
end