2 files changed, 34 insertions, 10 deletions
diff --git a/railties/lib/rails/rack/metal.rb b/railties/lib/rails/rack/metal.rb
index b185227234..adc43da864 100644
--- a/railties/lib/rails/rack/metal.rb
+++ b/railties/lib/rails/rack/metal.rb
@@ -6,15 +6,30 @@ module Rails
       NotFoundResponse = [404, {}, []].freeze
       NotFound = lambda { NotFoundResponse }
 
+      cattr_accessor :metal_paths
+      self.metal_paths = ["#{Rails.root}/app/metal"]
+      cattr_accessor :requested_metals
+
       def self.metals
-        base = "#{Rails.root}/app/metal"
-        matcher = /\A#{Regexp.escape(base)}\/(.*)\.rb\Z/
+        matcher = /#{Regexp.escape('/app/metal/')}(.*)\.rb\Z/
+        metal_glob = metal_paths.map{ |base| "#{base}/**/*.rb" }
+        all_metals = {}
 
-        Dir["#{base}/**/*.rb"].sort.map do |file|
-          file.sub!(matcher, '\1')
-          require file
-          file.classify.constantize
+        metal_glob.each do |glob|
+          Dir[glob].sort.map do |file|
+            file = file.match(matcher)[1]
+            all_metals[file.camelize] = file
+          end
         end
+
+        load_list = requested_metals || all_metals.keys
+
+        load_list.map do |requested_metal|
+          if metal = all_metals[requested_metal]
+            require metal
+            requested_metal.constantize
+          end
+        end.compact
       end
 
       def initialize(app)
diff --git a/railties/lib/rails/rack/static.rb b/railties/lib/rails/rack/static.rb
index ef4e2642e2..f07c6beb5e 100644
--- a/railties/lib/rails/rack/static.rb
+++ b/railties/lib/rails/rack/static.rb
@@ -13,14 +13,18 @@ module Rails
       def call(env)
         path        = env['PATH_INFO'].chomp('/')
         method      = env['REQUEST_METHOD']
-        cached_path = (path.empty? ? 'index' : path) + ::ActionController::Base.page_cache_extension
 
         if FILE_METHODS.include?(method)
           if file_exist?(path)
             return @file_server.call(env)
-          elsif file_exist?(cached_path)
-            env['PATH_INFO'] = cached_path
-            return @file_server.call(env)
+          else
+            cached_path = directory_exist?(path) ? "#{path}/index" : path
+            cached_path += ::ActionController::Base.page_cache_extension
+
+            if file_exist?(cached_path)
+              env['PATH_INFO'] = cached_path
+              return @file_server.call(env)
+            end
           end
         end
 
@@ -32,6 +36,11 @@ module Rails
           full_path = File.join(@file_server.root, ::Rack::Utils.unescape(path))
           File.file?(full_path) && File.readable?(full_path)
         end
+
+        def directory_exist?(path)
+          full_path = File.join(@file_server.root, ::Rack::Utils.unescape(path))
+          File.directory?(full_path) && File.readable?(full_path)
+        end
     end
   end
 end