# File lib/fog/rackspace/models/compute_v2/image.rb, line 49
        def ready?(ready_state = ACTIVE, error_states=[ERROR])
          if error_states
            error_states = Array(error_states)
            raise "Image should have transitioned to '#{ready_state}' not '#{state}'" if error_states.include?(state)
          end
          state == ready_state
        end