question.rb

gistfile1.rb

def create
  respond_to do |format|
    format.json do
      if @my_model.save!
        render :json => @my_model.to_json(:methods => [:owner_name]) #owner_name is a method that returns owner.display_name
      end
    end
    format html do
      if @my_model.save!
       ...
      end
    end
  end
end