active_record_mimic.rb

require 'model_attribute'

module ActiveRecordMimic
  def self.included(base)
    base.instance_eval do
      unless (class << base; self; end).ancestors.include?(ModelAttribute)
        raise "ActiveRecordMimic aliases ModelAttribute methods so must be included after extending ModelAttribute"
      end

      alias_method :[],  :read_attribute
      alias_method :[]=, :write_attribute

      # Forward these behaviours to base.class e.g Message.api_class
      delegate :api_class,
               :sti_class,
               :base_class,
               :to => base

      def self.sti_class
        self
      end

      def self.base_class
        self
      end

      def self.primary_key
        :id
      end
    end
  end

  def destroyed?
    !!@destroyed
  end

  def new_record?
    !id
  end

  def persisted?
    !(new_record? || destroyed?)
  end

  # This allows us to use this object as a hash key, and for uniq'ing arrays
  def hash
    id.hash
  end

  # Action Pack uses this for constructing a URL to this object.
  def to_param
    id && id.to_s
  end

  def update_attribute(attr_name, new_val)
    write_attribute(attr_name, new_val)
    save
  end

  def changed?
    changes.any?
  end
end