Lightweight futures in Ruby (with Rails example)

future.rb

class Future < Thread
  def result
    join
    value
  end
end

home_controller.rb

class HomeController < ApplicationController
  def index
    @page = HomePage.new
  end
end

home_page.rb

class HomePage
  attr_reader :data

  def initialize
    @data = {
      featured_items: Future.new { http_fetch(:featured_items) },
      grid_items:     Future.new { http_fetch(:grid_items) }
    }
  end
  
  def featured_items
    @featured_items ||= data[:featured_items].result
  end
  
  def grid_items
    @grid_items ||= data[:grid_items].result
  end
end