gistfile1.rb

module DoodlekitExtensions
  module ContentFilter extend ActiveSupport::Concern
    
    module ClassMethods
      def content_filter(field, options = {}) 
        before_save { |r| r.apply_filter(field)}
        include DoodlekitExtensions::ContentFilter::InstanceMethods    
      end 
    end 
    
    module InstanceMethods
      def apply_filter(field)
        self.send("#{field.to_s}=", filter(self.send("#{field}")))
      end 
          
      def filter(s)
        s.nil? ? s : s.gsub(/<style>.*<\/style>/mi, '') 
      end 
          
    end 
  end 
end

Doodlekit::Application.config.after_initialize do
  ActiveRecord::Base.send(:include, DoodlekitExtensions::ContentFilter)
end