Override devise registrations controller

A better and more organized way of overriding Devise controllers and views using namespaces:

Create the following folders:

app/controllers/my_devise
app/views/my_devise

Put all controllers that you want to override into app/controllers/my_devise and add MyDevise namespace to controller class names. Registrations example:

# app/controllers/my_devise/registrations_controller.rb
class MyDevise::RegistrationsController < Devise::RegistrationsController

  ...

  def create
    # add custom create logic here
  end

  ...    

end 

Change your routes accordingly:

devise_for :users,
           :controllers  => {
             :registrations => 'my_devise/registrations',
             # ...
           }

Copy all required views into app/views/my_devise from Devise gem folder or use rails generate devise:views, delete the views you are not overriding and rename devise folder to my_devise.

This way you will have everything neatly organized in two folders.

I believe there is a better solution than rewrite the RegistrationsController. I did exactly the same thing (I just have Organization instead of Company).

If you set properly your nested form, at model and view level, everything works like a charm.

My User model:

class User < ActiveRecord::Base
  # Include default devise modules. Others available are:
  # :token_authenticatable, :confirmable, :lockable and :timeoutable
  devise :database_authenticatable, :registerable,
     :recoverable, :rememberable, :trackable, :validatable

  has_many :owned_organizations, :class_name => 'Organization', :foreign_key => :owner_id

  has_many :organization_memberships
  has_many :organizations, :through => :organization_memberships

  # Setup accessible (or protected) attributes for your model
  attr_accessible :email, :password, :password_confirmation, :remember_me, :name, :username, :owned_organizations_attributes

  accepts_nested_attributes_for :owned_organizations
  ...
end

My Organization Model:

class Organization < ActiveRecord::Base
  belongs_to :owner, :class_name => 'User'
  has_many :organization_memberships
  has_many :users, :through => :organization_memberships
  has_many :contracts

  attr_accessor :plan_name

  after_create :set_owner_membership, :set_contract
  ...
end

My view : 'devise/registrations/new.html.erb'

<h2>Sign up</h2>

<% resource.owned_organizations.build if resource.owned_organizations.empty? %>
<%= 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>

  <p><%= f.label :email %><br />
    <%= f.text_field :email %></p>

  <p><%= f.label :username %><br />
    <%= f.text_field :username %></p>

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

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

  <%= f.fields_for :owned_organizations do |organization_form| %>

    <p><%= organization_form.label :name %><br />
      <%= organization_form.text_field :name %></p>

    <p><%= organization_form.label :subdomain %><br />
      <%= organization_form.text_field :subdomain %></p>

    <%= organization_form.hidden_field :plan_name, :value => params[:plan] %>

  <% end %>

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

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

In your form are you passing in any other attributes, via mass assignment that don't belong to your user model, or any of the nested models?

If so, I believe the ActiveRecord::UnknownAttributeError is triggered in this instance.

Otherwise, I think you can just create your own controller, by generating something like this:

# app/controllers/registrations_controller.rb
class RegistrationsController < Devise::RegistrationsController
  def new
    super
  end

  def create
    # add custom create logic here
  end

  def update
    super
  end
end 

And then tell devise to use that controller instead of the default with:

# app/config/routes.rb
devise_for :users, :controllers => {:registrations => "registrations"}