borrow_active_record_serialization.rb

require 'rubygems'
require 'active_record'

class Salutations
  attr_accessor :greeting, :farewell
  def initialize(greeting, farewell)
    @greeting = greeting
    @farewell = farewell
  end
  
  include ActiveRecord::Serialization
  def self.inheritance_column
  end
  
  def self.serialized_attributes
    {}
  end
  
  def self.columns_hash
    type_struct = Struct.new(:type)
    string_type = type_struct.new(:string)
    {"greeting" => string_type, "farewell" => string_type}
  end
  
  def attribute_names
    ["greeting", "farewell"]
  end
end

s = Salutations.new("hello", "goodbye")

s.to_xml
#=> <?xml version="1.0" encoding="UTF-8"?>
#   <salutations>
#     <greeting>hello</greeting>
#     <farewell>goodbye</farewell>
#   </salutations>

s.to_json
#=> {"greeting": "hello", "farewell": "goodbye"}