Hexagonal Rails with Responder Objects

gistfile1.rb

class GetItemService < Struct.new( :id, :responder )
  def get
    item = Item.find( id )
    item ? responder.success( item ) : responder.failure( item )
  end
end

class GetItemResponder < SimpleDelegator
  def success( item )
    @item = item
    render( "show" )
  end
  def failure
    # handle failure -- render a 404, or whatever
  end
end

class ItemsController < ApplicationController
  def show
    GetItemService.new( params[:id], GetItemResponder.new( self ) ).get
  end
end