Move development mode reloading up the stack to avoid issues with class reloading in middleware

actionpack/lib/action_controller.rb

@@ -59,6 +59,7 @@ module ActionController
   autoload :ParamsParser, 'action_controller/params_parser'
   autoload :PolymorphicRoutes, 'action_controller/polymorphic_routes'
   autoload :RecordIdentifier, 'action_controller/record_identifier'
+  autoload :Reloader, 'action_controller/reloader'
   autoload :Request, 'action_controller/request'
   autoload :RequestForgeryProtection, 'action_controller/request_forgery_protection'
   autoload :Rescue, 'action_controller/rescue'

actionpack/lib/action_controller/dispatcher.rb

@@ -5,8 +5,9 @@ module ActionController
     class << self
       def define_dispatcher_callbacks(cache_classes)
         unless cache_classes
-          # Development mode callbacks
-          before_dispatch :reload_application
+          unless self.middleware.include?(Reloader)
+            self.middleware.insert_after(Failsafe, Reloader)
+          end
 
           ActionView::Helpers::AssetTagHelper.cache_asset_timestamps = false
         end
@@ -41,6 +42,30 @@ module ActionController
         callback = ActiveSupport::Callbacks::Callback.new(:prepare_dispatch, block, :identifier => identifier)
         @prepare_dispatch_callbacks.replace_or_append!(callback)
       end
+
+      def run_prepare_callbacks
+        if defined?(Rails) && Rails.logger
+          logger = Rails.logger
+        else
+          logger = Logger.new($stderr)
+        end
+
+        new(logger).send :run_callbacks, :prepare_dispatch
+      end
+
+      def reload_application
+        # Run prepare callbacks before every request in development mode
+        run_prepare_callbacks
+
+        Routing::Routes.reload
+      end
+
+      def cleanup_application
+        # Cleanup the application before processing the current request.
+        ActiveRecord::Base.reset_subclasses if defined?(ActiveRecord)
+        ActiveSupport::Dependencies.clear
+        ActiveRecord::Base.clear_reloadable_connections! if defined?(ActiveRecord)
+      end
     end
 
     cattr_accessor :middleware
@@ -87,18 +112,6 @@ module ActionController
       dispatch
     end
 
-    def reload_application
-      # Cleanup the application before processing the current request.
-      ActiveRecord::Base.reset_subclasses if defined?(ActiveRecord)
-      ActiveSupport::Dependencies.clear
-      ActiveRecord::Base.clear_reloadable_connections! if defined?(ActiveRecord)
-
-      # Run prepare callbacks before every request in development mode
-      run_callbacks :prepare_dispatch
-
-      Routing::Routes.reload
-    end
-
     def flush_logger
       Base.logger.flush
     end

actionpack/lib/action_controller/reloader.rb

@@ -0,0 +1,14 @@
+module ActionController
+  class Reloader
+    def initialize(app)
+      @app = app
+    end
+
+    def call(env)
+      Dispatcher.reload_application
+      @app.call(env)
+    ensure
+      Dispatcher.cleanup_application
+    end
+  end
+end

actionpack/test/controller/dispatcher_test.rb

@@ -6,14 +6,17 @@ class DispatcherTest < Test::Unit::TestCase
   def setup
     ENV['REQUEST_METHOD'] = 'GET'
 
+    Dispatcher.middleware = ActionController::MiddlewareStack.new do |middleware|
+      middlewares = File.expand_path(File.join(File.dirname(__FILE__), "../../lib/action_controller/middlewares.rb"))
+      middleware.instance_eval(File.read(middlewares))
+    end
+
     # Clear callbacks as they are redefined by Dispatcher#define_dispatcher_callbacks
     Dispatcher.instance_variable_set("@prepare_dispatch_callbacks", ActiveSupport::Callbacks::CallbackChain.new)
     Dispatcher.instance_variable_set("@before_dispatch_callbacks", ActiveSupport::Callbacks::CallbackChain.new)
     Dispatcher.instance_variable_set("@after_dispatch_callbacks", ActiveSupport::Callbacks::CallbackChain.new)
 
     Dispatcher.stubs(:require_dependency)
-
-    @dispatcher = Dispatcher.new
   end
 
   def teardown
@@ -65,7 +68,7 @@ class DispatcherTest < Test::Unit::TestCase
     assert_nil a || b || c
 
     # Run callbacks
-    @dispatcher.send :run_callbacks, :prepare_dispatch
+    Dispatcher.run_prepare_callbacks
 
     assert_equal 1, a
     assert_equal 2, b
@@ -82,7 +85,7 @@ class DispatcherTest < Test::Unit::TestCase
     Dispatcher.to_prepare(:unique_id) { |*args| a = b = 1 }
     Dispatcher.to_prepare(:unique_id) { |*args| a = 2 }
 
-    @dispatcher.send :run_callbacks, :prepare_dispatch
+    Dispatcher.run_prepare_callbacks
     assert_equal 2, a
     assert_equal nil, b
   end
@@ -91,7 +94,7 @@ class DispatcherTest < Test::Unit::TestCase
     def dispatch(cache_classes = true)
       ActionController::Routing::RouteSet.any_instance.stubs(:call).returns([200, {}, 'response'])
       Dispatcher.define_dispatcher_callbacks(cache_classes)
-      @dispatcher.call({})
+      Dispatcher.new.call({})
     end
 
     def assert_subclasses(howmany, klass, message = klass.subclasses.inspect)

railties/lib/console_app.rb

@@ -24,7 +24,6 @@ end
 #reloads the environment
 def reload!
   puts "Reloading..."
-  dispatcher = ActionController::Dispatcher.new($stdout)
-  dispatcher.reload_application
+  Dispatcher.reload_application
   true
 end

railties/lib/initializer.rb

@@ -583,7 +583,7 @@ Run `rake gems:install` to install the missing gems.
       return unless configuration.frameworks.include?(:action_controller)
       require 'dispatcher' unless defined?(::Dispatcher)
       Dispatcher.define_dispatcher_callbacks(configuration.cache_classes)
-      Dispatcher.new(Rails.logger).send :run_callbacks, :prepare_dispatch
+      Dispatcher.run_prepare_callbacks
     end
 
     def disable_dependency_loading