ActiveSupport::Concern

active_record_extension.rb

#lib/active_record_extension.rb
module ActiveRecordExtension #-> http://stackoverflow.com/questions/2328984/rails-extending-activerecordbase

  extend ActiveSupport::Concern

  included do
    class_attribute :store_base_sti_class
    self.store_base_sti_class = true
  end
end

# include the extension 
ActiveRecord::Base.send(:include, ActiveRecordExtension)

###

module AddPolymorphic
  extend ActiveSupport::Concern
  
  included do #-> http://stackoverflow.com/questions/28214874/overriding-methods-in-an-activesupportconcern-module-which-are-defined-by-a-cl
    define_method :replace_keys do |record=nil|
      super(record)
      owner[reflection.foreign_type] = ActiveRecord::Base.store_base_sti_class ? record.class.base_class.name : record.class.name
    end
  end
end

ActiveRecord::Associations::BelongsToPolymorphicAssociation.send(:include, AddPolymorphic)

####

sti_base.rb

#config/initializers/sti_base.rb
require "active_record"
require "active_record_extension"
ActiveRecord::Base.store_base_sti_class = false