warm_page_cache.rb

  ## How to warm caches_page with delayed_job (or any other async worker)
  ## Why build it on the fly, when you can build it in advance.
  
  def perform
    require 'action_controller/integration'
    app = ActionController::Integration::Session.new
    app.host! thing_host # for a system with subdomains
    app.get thing_path
    app.get next_thing_path
  end