1 files changed, 27 insertions, 0 deletions
diff --git a/railties/lib/rails/rack/metal.rb b/railties/lib/rails/rack/metal.rb
new file mode 100644
index 0000000000..1df31a1594
--- /dev/null
+++ b/railties/lib/rails/rack/metal.rb
@@ -0,0 +1,27 @@
+require 'rails/rack/cascade'
+
+module Rails
+  module Rack
+    module Metal
+      NotFoundResponse = [404, {}, []].freeze
+      NotFound = lambda { NotFoundResponse }
+
+      class << self
+        def new(app)
+          Cascade.new(builtins + [app])
+        end
+
+        def builtins
+          base = "#{Rails.root}/app/metal"
+          matcher = /\A#{Regexp.escape(base)}\/(.*)\.rb\Z/
+
+          Dir["#{base}/**/*.rb"].sort.map do |file|
+            file.sub!(matcher, '\1')
+            require file
+            file.classify.constantize
+          end
+        end
+      end
+    end
+  end
+end