poor man's state machine

gistfile1.rb

  #
  # move the following into lib/state_machine.rb or something?
  # Also, the state transitions are not really atomic...
  # works fine for now, but should fix eventually
  #
  %w(
    new
    validating
    valid
    invalid
    ready
    running
    finished
    failed
    stopped
  ).each do |status_entry|
    class_eval <<-EOS
      def in_state_#{status_entry}? 
        self.status == "#{status_entry}"
      end
      def set_state_#{status_entry}(should_save = true)
        self.status_updated_at = Time.now
        self.status = "#{status_entry}"
        if should_save
          self.update_attribute(:status, status)
        end
      end
    EOS
    instance_eval <<-EOS
      named_scope :in_state_#{status_entry}, :conditions => [ 'status = ?', "#{status_entry}" ]
    EOS
  end