Automatically Sanitize fields for HTML display

# Sanitizing/Escaping HTML in the view is inefficient because it
# happens every time the view is rendered.  This module forces
# text and string fields to be sanitized every time they are 
# modified and saved to the database.  
module Sanitizer
  def sanitize_fields
    columns = self.class.columns_hash
    changes.each do |key,value|
      if columns[key].type == :text
        Sanitize.clean! value[1], Sanitize::Config::TEXTAREA
      elsif columns[key].type == :string
        Sanitize.clean! value[1], Sanitize::Config::TEXTFIELD
      end
      value[1].strip! if value[1].is_a? String
    end
  end
end
module ActiveRecord
  class Base
    include Sanitizer
    before_save :sanitize_fields
  end
end