Extract routes reloading responsibilities from application and load them just upon a request.

actionpack/lib/action_dispatch/middleware/callbacks.rb

@@ -37,7 +37,7 @@ module ActionDispatch
 
     def initialize(app, prepare_each_request = false)
       @app, @prepare_each_request = app, prepare_each_request
-      run_callbacks(:prepare)
+      run_callbacks(:prepare) unless @prepare_each_request
     end
 
     def call(env)

actionpack/lib/action_dispatch/railtie.rb

@@ -5,22 +5,14 @@ module ActionDispatch
   class Railtie < Rails::Railtie
     plugin_name :action_dispatch
 
+    # Initialize route files to an array
+    config.action_dispatch.route_files = []
+
     # Prepare dispatcher callbacks and run 'prepare' callbacks
     initializer "action_dispatch.prepare_dispatcher" do |app|
       # TODO: This used to say unless defined?(Dispatcher). Find out why and fix.
       require 'rails/dispatcher'
-
-      unless app.config.cache_classes
-        # Setup dev mode route reloading
-        routes_last_modified = app.routes_changed_at
-        reload_routes = lambda do
-          unless app.routes_changed_at == routes_last_modified
-            routes_last_modified = app.routes_changed_at
-            app.reload_routes!
-          end
-        end
-        ActionDispatch::Callbacks.before { |callbacks| reload_routes.call }
-      end
+      ActionDispatch::Callbacks.to_prepare { app.routes_reloader.reload_if_changed }
     end
   end
 end

railties/lib/rails/application.rb

@@ -2,25 +2,20 @@ require 'fileutils'
 
 module Rails
   class Application < Engine
-    # TODO Clear up 2 way delegation flow between App class and instance.
-    # Infact just add a method_missing on the class.
-    #
-    # TODO I'd like to track the "default app" different using an inherited hook.
-    #
+    autoload :RoutesReloader, 'rails/application/routes_reloader'
+
     # TODO Check helpers works as expected
-    #
     # TODO Check routes namespaces
     class << self
-      alias    :configure :class_eval
-      delegate :initialize!, :load_tasks, :load_generators, :root, :to => :instance
-
       private :new
+      alias   :configure :class_eval
+
       def instance
         @instance ||= new
       end
 
       def config
-        @config ||= Configuration.new(original_root)
+        @config ||= Configuration.new(self.original_root)
       end
 
       def original_root
@@ -30,53 +25,36 @@ module Rails
       def inherited(base)
         super
         Railtie.plugins.delete(base)
+        Rails.application = base.instance
       end
 
-      def routes
-        ActionController::Routing::Routes
+    protected
+
+      def method_missing(*args, &block)
+        instance.send(*args, &block)
       end
     end
 
-    delegate :routes, :to => :'self.class'
-    attr_reader :route_configuration_files
-
     def initialize
       require_environment
-      Rails.application ||= self
-      @route_configuration_files = []
+    end
+
+    def routes
+      ActionController::Routing::Routes
+    end
+
+    def routes_reloader
+      @routes_reloader ||= RoutesReloader.new(config)
+    end
+
+    def reload_routes!
+      routes_reloader.reload!
     end
 
     def initialize!
       run_initializers(self)
       self
     end
-    
-    def routes_changed_at
-      routes_changed_at = nil
-
-      route_configuration_files.each do |config|
-        config_changed_at = File.stat(config).mtime
-
-        if routes_changed_at.nil? || config_changed_at > routes_changed_at
-          routes_changed_at = config_changed_at
-        end
-      end
-
-      routes_changed_at
-    end
-
-    def reload_routes!
-      routes = Rails::Application.routes
-      routes.disable_clear_and_finalize = true
-
-      routes.clear!
-      route_configuration_files.each { |config| load(config) }
-      routes.finalize!
-
-      nil
-    ensure
-      routes.disable_clear_and_finalize = false
-    end
 
     def require_environment
       environment = config.paths.config.environment.to_a.first
@@ -109,10 +87,7 @@ module Rails
     end
 
     def app
-      @app ||= begin
-        reload_routes!
-        middleware.build(routes)
-      end
+      @app ||= middleware.build(routes)
     end
 
     def call(env)
@@ -207,7 +182,7 @@ module Rails
 
       initializer :add_builtin_route do |app|
         if Rails.env.development?
-          app.route_configuration_files << File.join(RAILTIES_PATH, 'builtin', 'routes.rb')
+          app.config.action_dispatch.route_files << File.join(RAILTIES_PATH, 'builtin', 'routes.rb')
         end
       end
 

railties/lib/rails/application/routes_reloader.rb

@@ -0,0 +1,46 @@
+module Rails
+  class Application
+    class RoutesReloader
+      attr_reader :config
+
+      def initialize(config)
+        @config, @last_change_at = config, nil
+      end
+
+      def changed_at
+        routes_changed_at = nil
+
+        config.action_dispatch.route_files.each do |config|
+          config_changed_at = File.stat(config).mtime
+
+          if routes_changed_at.nil? || config_changed_at > routes_changed_at
+            routes_changed_at = config_changed_at
+          end
+        end
+
+        routes_changed_at
+      end
+
+      def reload!
+        routes = Rails::Application.routes
+        routes.disable_clear_and_finalize = true
+
+        routes.clear!
+        config.action_dispatch.route_files.each { |config| load(config) }
+        routes.finalize!
+
+        nil
+      ensure
+        routes.disable_clear_and_finalize = false
+      end
+
+      def reload_if_changed
+        current_change_at = changed_at
+        if @last_change_at != current_change_at
+          @last_change_at = current_change_at
+          reload!
+        end
+      end
+    end
+  end
+end

railties/lib/rails/configuration.rb

@@ -213,10 +213,7 @@ module Rails
       self.preload_frameworks = true
       self.cache_classes = true
       self.dependency_loading = false
-
-      if respond_to?(:action_controller)
-        action_controller.allow_concurrency = true
-      end
+      action_controller.allow_concurrency = true if respond_to?(:action_controller)
       self
     end
 

railties/lib/rails/console_app.rb

@@ -26,7 +26,6 @@ end
 #reloads the environment
 def reload!
   puts "Reloading..."
-  ActionDispatch::Callbacks.new(lambda {}, true)
-  Rails.application.reload_routes!
+  ActionDispatch::Callbacks.new(lambda {}, true).call({})
   true
 end

railties/lib/rails/engine.rb

@@ -1,8 +1,6 @@
 require 'active_support/core_ext/module/delegation'
 
 module Rails
-  # TODO Move I18n here
-  # TODO Set routes namespaces
   class Engine < Railtie
     class << self
       attr_accessor :called_from
@@ -75,9 +73,9 @@ module Rails
       config.load_once_paths.freeze
     end
 
-    initializer :add_routing_files do |app|
+    initializer :add_routing_files do
       config.paths.config.routes.to_a.each do |route|
-        app.route_configuration_files.unshift(route) if File.exists?(route)
+        config.action_dispatch.route_files.unshift(route) if File.exists?(route)
       end
     end
 

railties/lib/rails/plugin.rb

@@ -60,8 +60,7 @@ module Rails
     initializer :add_routing_file, :after => :initialize_routing do |app|
       routing_file = "#{path}/config/routes.rb"
       if File.exist?(routing_file)
-        app.route_configuration_files << routing_file
-        app.reload_routes!
+        app.config.action_dispatch.route_files.unshift(routing_file)
       end
     end
   end