Devise and OAuth

devise_user.rb

class DeviseUser < ActiveRecord::Base
  devise :database_authenticatable, :registerable, :recoverable, :rememberable, :trackable, :validatable
  attr_accessible :email, :name, :password, :password_confirmation, :remember_me

  has_many :posts, :as => :authorizable
end

oauth_user.rb

class OAuthUser < ActiveRecord::Base
  devise :omniauthable
  has_many :post, :as => :authorizable
end

post.rb

class Post < ActiveRecord::Base
  belongs_to :authorizable, :polymorphic => true
end