six rules ror app usage example

user.rb

# app/models/user.rb

class User < ActiveRecord::Base
  include Allowed::UserRules
end

user_rules.rb

# lib/allowed/user_rules.rb
 
module Allowed::UserRules
  extend ActiveSupport::Concern
 
  def allowed(object, subject)
    rules = []
    return rules unless subject.kind_of?(::User)
 
    if object && object.persisted?
      rules << :show
      if subject == object
        rules << :friends
        rules << :update
      end
    else
      rules << :create
    end
 
    rules
  end
end