--- /dev/null
+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
+ @@guard = Mutex.new
+
+ class << self
+ def define_dispatcher_callbacks(cache_classes)
+ unless cache_classes
+ # Development mode callbacks
+ before_dispatch :reload_application
+ after_dispatch :cleanup_application
+ end
+
+ # Common callbacks
+ to_prepare :load_application_controller do
+ begin
+ require_dependency 'application' unless defined?(::ApplicationController)
+ rescue LoadError => error
+ raise unless error.message =~ /application\.rb/
+ end
+ 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
+
+ # Backward-compatible class method takes CGI-specific args. Deprecated
+ # in favor of Dispatcher.new(output, request, response).dispatch.
+ 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
+
+ # If the block raises, send status code as a last-ditch response.
+ def failsafe_response(fallback_output, status, originating_exception = nil)
+ yield
+ rescue Exception => exception
+ begin
+ log_failsafe_exception(status, originating_exception || exception)
+ body = failsafe_response_body(status)
+ fallback_output.write "Status: #{status}\r\nContent-Type: text/html\r\n\r\n#{body}"
+ nil
+ rescue Exception => failsafe_error # Logger or IO errors
+ $stderr.puts "Error during failsafe response: #{failsafe_error}"
+ $stderr.puts "(originally #{originating_exception})" if originating_exception
+ end
+ end
+
+ private
+ def failsafe_response_body(status)
+ error_path = "#{error_file_path}/#{status.to_s[0..3]}.html"
+
+ if File.exist?(error_path)
+ File.read(error_path)
+ else
+ "<html><body><h1>#{status}</h1></body></html>"
+ end
+ end
+
+ def log_failsafe_exception(status, exception)
+ message = "/!\\ FAILSAFE /!\\ #{Time.now}\n Status: #{status}\n"
+ message << " #{exception}\n #{exception.backtrace.join("\n ")}" if exception
+ failsafe_logger.fatal message
+ end
+
+ def failsafe_logger
+ if defined?(::RAILS_DEFAULT_LOGGER) && !::RAILS_DEFAULT_LOGGER.nil?
+ ::RAILS_DEFAULT_LOGGER
+ else
+ Logger.new($stderr)
+ end
+ end
+ end
+
+ cattr_accessor :error_file_path
+ self.error_file_path = Rails.public_path if defined?(Rails.public_path)
+
+ include ActiveSupport::Callbacks
+ define_callbacks :prepare_dispatch, :before_dispatch, :after_dispatch
+
+ def initialize(output = $stdout, request = nil, response = nil)
+ @output, @request, @response = output, request, response
+ end
+
+ def dispatch_unlocked
+ begin
+ run_callbacks :before_dispatch
+ handle_request
+ rescue Exception => exception
+ failsafe_rescue exception
+ ensure
+ run_callbacks :after_dispatch, :enumerator => :reverse_each
+ end
+ end
+
+ def dispatch
+ if ActionController::Base.allow_concurrency
+ dispatch_unlocked
+ else
+ @@guard.synchronize do
+ dispatch_unlocked
+ end
+ end
+ end
+
+ def dispatch_cgi(cgi, session_options)
+ if cgi ||= self.class.failsafe_response(@output, '400 Bad Request') { CGI.new }
+ @request = CgiRequest.new(cgi, session_options)
+ @response = CgiResponse.new(cgi)
+ dispatch
+ end
+ rescue Exception => exception
+ failsafe_rescue exception
+ end
+
+ def call(env)
+ @request = RackRequest.new(env)
+ @response = RackResponse.new(@request)
+ dispatch
+ end
+
+ def reload_application
+ # Run prepare callbacks before every request in development mode
+ run_callbacks :prepare_dispatch
+
+ Routing::Routes.reload
+ ActionController::Base.view_paths.reload!
+ ActionView::Helpers::AssetTagHelper::AssetTag::Cache.clear
+ 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 mark_as_test_request!
+ @test_request = true
+ self
+ end
+
+ def test_request?
+ @test_request
+ end
+
+ def checkin_connections
+ # Don't return connection (and peform implicit rollback) if this request is a part of integration test
+ return if test_request?
+ ActiveRecord::Base.clear_active_connections!
+ end
+
+ protected
+ def handle_request
+ @controller = Routing::Routes.recognize(@request)
+ @controller.process(@request, @response).out(@output)
+ end
+
+ def failsafe_rescue(exception)
+ self.class.failsafe_response(@output, '500 Internal Server Error', exception) do
+ if @controller ||= defined?(::ApplicationController) ? ::ApplicationController : Base
+ @controller.process_with_exception(@request, @response, exception).out(@output)
+ else
+ raise exception
+ end
+ end
+ end
+ end
+end
projects / depot.git / blobdiff