1 files changed, 116 insertions, 0 deletions
diff --git a/actionpack/lib/action_controller/dispatch/dispatcher.rb b/actionpack/lib/action_controller/dispatch/dispatcher.rb
new file mode 100644
index 0000000000..714e270781
--- /dev/null
+++ b/actionpack/lib/action_controller/dispatch/dispatcher.rb
@@ -0,0 +1,116 @@
+module ActionController
+  # Dispatches requests to the appropriate controller and takes care of
+  # reloading the app after each request when Dependencies.load? is true.
+  class Dispatcher
+    class << self
+      def define_dispatcher_callbacks(cache_classes)
+        unless cache_classes
+          # Development mode callbacks
+          before_dispatch :reload_application
+          after_dispatch :cleanup_application
+
+          ActionView::Helpers::AssetTagHelper.cache_asset_timestamps = false
+        end
+
+        if defined?(ActiveRecord)
+          after_dispatch :checkin_connections
+          to_prepare(:activerecord_instantiate_observers) { ActiveRecord::Base.instantiate_observers }
+        end
+
+        after_dispatch :flush_logger if Base.logger && Base.logger.respond_to?(:flush)
+
+        to_prepare do
+          I18n.reload!
+        end
+      end
+
+      # DEPRECATE: Remove CGI support
+      def dispatch(cgi = nil, session_options = CgiRequest::DEFAULT_SESSION_OPTIONS, output = $stdout)
+        new(output).dispatch_cgi(cgi, session_options)
+      end
+
+      # Add a preparation callback. Preparation callbacks are run before every
+      # request in development mode, and before the first request in production
+      # mode.
+      #
+      # An optional identifier may be supplied for the callback. If provided,
+      # to_prepare may be called again with the same identifier to replace the
+      # existing callback. Passing an identifier is a suggested practice if the
+      # code adding a preparation block may be reloaded.
+      def to_prepare(identifier = nil, &block)
+        @prepare_dispatch_callbacks ||= ActiveSupport::Callbacks::CallbackChain.new
+        callback = ActiveSupport::Callbacks::Callback.new(:prepare_dispatch, block, :identifier => identifier)
+        @prepare_dispatch_callbacks.replace_or_append!(callback)
+      end
+    end
+
+    cattr_accessor :middleware
+    self.middleware = MiddlewareStack.new do |middleware|
+      middlewares = File.join(File.dirname(__FILE__), "rack", "middlewares.rb")
+      middleware.instance_eval(File.read(middlewares))
+    end
+
+    include ActiveSupport::Callbacks
+    define_callbacks :prepare_dispatch, :before_dispatch, :after_dispatch
+
+    # DEPRECATE: Remove arguments, since they are only used by CGI
+    def initialize(output = $stdout, request = nil, response = nil)
+      @output = output
+      @app = @@middleware.build(lambda { |env| self.dup._call(env) })
+    end
+
+    def dispatch
+      begin
+        run_callbacks :before_dispatch
+        Routing::Routes.call(@env)
+      rescue Exception => exception
+        if controller ||= (::ApplicationController rescue Base)
+          controller.call_with_exception(@env, exception).to_a
+        else
+          raise exception
+        end
+      ensure
+        run_callbacks :after_dispatch, :enumerator => :reverse_each
+      end
+    end
+
+    # DEPRECATE: Remove CGI support
+    def dispatch_cgi(cgi, session_options)
+      CGIHandler.dispatch_cgi(self, cgi, @output)
+    end
+
+    def call(env)
+      @app.call(env)
+    end
+
+    def _call(env)
+      @env = env
+      dispatch
+    end
+
+    def reload_application
+      # Run prepare callbacks before every request in development mode
+      run_callbacks :prepare_dispatch
+
+      Routing::Routes.reload
+    end
+
+    # Cleanup the application by clearing out loaded classes so they can
+    # be reloaded on the next request without restarting the server.
+    def cleanup_application
+      ActiveRecord::Base.reset_subclasses if defined?(ActiveRecord)
+      ActiveSupport::Dependencies.clear
+      ActiveRecord::Base.clear_reloadable_connections! if defined?(ActiveRecord)
+    end
+
+    def flush_logger
+      Base.logger.flush
+    end
+
+    def checkin_connections
+      # Don't return connection (and peform implicit rollback) if this request is a part of integration test
+      return if @env.key?("rack.test")
+      ActiveRecord::Base.clear_active_connections!
+    end
+  end
+end