load_rack_cache

# File railties/lib/rails/application/default_middleware_stack.rb, line 113
        def load_rack_cache
          rack_cache = config.action_dispatch.rack_cache
          return unless rack_cache

          begin
            require "rack/cache"
          rescue LoadError => error
            error.message << " Be sure to add rack-cache to your Gemfile"
            raise
          end

          if rack_cache == true
            {
              metastore: "rails:/",
              entitystore: "rails:/",
              verbose: false
            }
          else
            rack_cache
          end
        end