This class is capable of spawning Ruby on Rails application instances quickly. This is done by preloading the Ruby on Rails framework into memory, before spawning the application instances.
A single FrameworkSpawner instance can only hold a single Ruby on Rails framework version. So be careful when using FrameworkSpawner: the applications that you spawn through it must require the same RoR version. To handle multiple RoR versions, use multiple FrameworkSpawner instances.
FrameworkSpawner uses ApplicationSpawner internally.
Note: FrameworkSpawner may only be started asynchronously with PhusionPassenger::AbstractServer#start. Starting it synchronously with PhusionPassenger::AbstractServer#start_synchronously has not been tested.
Creates a new instance of FrameworkSpawner.
Extra supported options:
framework_version
: The Ruby on Rails version to use. It is not
checked whether this version is actually installed.
All other options will be passed on to ApplicationSpawner and RequestHandler.
Note that the specified Rails framework will be loaded during the entire life time of the FrameworkSpawner server. If you wish to reload the Rails framework's code, then restart the server by calling PhusionPassenger::AbstractServer#stop and PhusionPassenger::AbstractServer#start.
# File lib/phusion_passenger/classic_rails/framework_spawner.rb, line 66 def initialize(options = {}) if !options.respond_to?(:'[]') raise ArgumentError, "The 'options' argument does not seem to be an options hash" end @framework_version = options["framework_version"] if options.has_key?("print_framework_loading_exceptions") @print_framework_loading_exceptions = options["print_framework_loading_exceptions"] else @print_framework_loading_exceptions = true end if !@framework_version raise ArgumentError, "The 'framework_version' option must specified" end super() @options = options self.max_idle_time = DEFAULT_FRAMEWORK_SPAWNER_MAX_IDLE_TIME define_message_handler(:spawn_application, :handle_spawn_application) define_message_handler(:reload, :handle_reload) end
Remove the cached application instances at the given group name. If nil is specified as group name, then all cached application instances will be removed, no matter the group name.
Long description: Application code might be cached in memory by a FrameworkSpawner. But once it a while, it will be necessary to reload the code for an application, such as after deploying a new version of the application. This method makes sure that any cached application code is removed, so that the next time an application instance is spawned, the application code will be freshly loaded into memory.
Raises:
FrameworkSpawner::Error: The FrameworkSpawner server exited unexpectedly.
# File lib/phusion_passenger/classic_rails/framework_spawner.rb, line 188 def reload(app_group_name = nil) connect do |channel| if app_group_name.nil? channel.write("reload") else channel.write("reload", app_group_name) end end rescue SystemCallError, IOError, SocketError raise Error, "The framework spawner server exited unexpectedly: #{e}" end
Spawn a RoR application using the Ruby on Rails framework version associated with this FrameworkSpawner. When successful, an Application object will be returned, which represents the spawned RoR application.
All options accepted by PhusionPassenger::ClassicRails::ApplicationSpawner.new and PhusionPassenger::ClassicRails::RequestHandler.new are accepted.
FrameworkSpawner will internally cache the code of applications, in order to speed up future spawning attempts. This implies that, if you've changed the application's code, you must do one of these things:
Restart this FrameworkSpawner by calling PhusionPassenger::AbstractServer#stop, then PhusionPassenger::AbstractServer#start.
Reload the application by calling reload with the correct app_root argument.
Raises:
AbstractServer::ServerNotStarted: The FrameworkSpawner server hasn't already been started.
AppInitError: The application raised an exception or called exit() during startup.
ApplicationSpawner::Error: The ApplicationSpawner server exited unexpectedly.
FrameworkSpawner::Error: The FrameworkSpawner server exited unexpectedly.
# File lib/phusion_passenger/classic_rails/framework_spawner.rb, line 140 def spawn_application(options = {}) app_root = options["app_root"] options = sanitize_spawn_options(options) options["app_root"] = app_root # No need for the ApplicationSpawner to print exceptions. All # exceptions raised by the ApplicationSpawner are sent back here, # so we just need to decide here whether we want to print it. print_exceptions = options["print_exceptions"] options["print_exceptions"] = false begin connect do |channel| channel.write("spawn_application", *options.to_a.flatten) result = channel.read if result.nil? raise IOError, "Connection closed" end if result[0] == 'exception' e = unmarshal_exception(channel.read_scalar) if print_exceptions && e.respond_to?(:child_exception) && e.child_exception print_exception(self.class.to_s, e.child_exception) elsif print_exceptions print_exception(self.class.to_s, e) end raise e else return AppProcess.read_from_channel(channel) end end rescue SystemCallError, IOError, SocketError => e raise Error, "The framework spawner server exited unexpectedly: #{e}" end end
Overrided from PhusionPassenger::AbstractServer#start.
May raise these additional exceptions:
FrameworkInitError: An error occurred while loading the specified Ruby on Rails framework.
FrameworkSpawner::Error: The FrameworkSpawner server exited unexpectedly.
# File lib/phusion_passenger/classic_rails/framework_spawner.rb, line 92 def start super begin channel = MessageChannel.new(@owner_socket) result = channel.read if result.nil? raise Error, "The framework spawner server exited unexpectedly." else status = result[0] end if status == 'exception' child_exception = unmarshal_exception(channel.read_scalar) stop message = "Could not load Ruby on Rails framework version #{@framework_version}: " << "#{child_exception.class} (#{child_exception.message})" options = { :version => @framework_version } if @print_framework_loading_exceptions print_exception(self.class.to_s, child_exception) end raise FrameworkInitError.new(message, child_exception, options) end rescue IOError, SystemCallError, SocketError => e stop if started? raise Error, "The framework spawner server exited unexpectedly: #{e}" rescue stop if started? raise end end
# File lib/phusion_passenger/classic_rails/framework_spawner.rb, line 299 def handle_reload(client, app_group_name = nil) @spawners.synchronize do if app_group_name @spawners.delete(app_group_name) else @spawners.clear end end end
# File lib/phusion_passenger/classic_rails/framework_spawner.rb, line 257 def handle_spawn_application(client, *options) app_process = nil options = sanitize_spawn_options(Hash[*options]) app_group_name = options["app_group_name"] @spawners.synchronize do begin spawner = @spawners.lookup_or_add(app_group_name) do spawner = ApplicationSpawner.new(@options.merge(options)) if options["app_spawner_timeout"] && options["app_spawner_timeout"] != -1 spawner.max_idle_time = options["app_spawner_timeout"] end spawner.start spawner end rescue InvalidPath, AppInitError, ApplicationSpawner::Error => e client.write('exception') client.write_scalar(marshal_exception(e)) if e.respond_to?(:child_exception) && e.child_exception.is_a?(LoadError) # A source file failed to load, maybe because of a # missing gem. If that's the case then the sysadmin # will install probably the gem. So we clear RubyGems's # cache so that it can detect new gems. Gem.clear_paths end return end begin app_process = spawner.spawn_application(options) rescue ApplicationSpawner::Error => e spawner.stop @spawners.delete(app_group_name) client.write('exception') client.write_scalar(marshal_exception(e)) return end end client.write('success') app_process.write_to_channel(client) ensure app_process.close if app_process end
# File lib/phusion_passenger/classic_rails/framework_spawner.rb, line 231 def preload_rails Object.const_set(:RAILS_ROOT, ".") gem 'rails', "=#{@framework_version}" require 'initializer' require 'active_support' require 'active_record' require 'action_controller' require 'action_view' require 'action_pack' require 'action_mailer' require 'dispatcher' begin if ::Rails::VERSION::MAJOR >= 2 require 'active_resource' else require 'action_web_service' end require 'ruby_version_check' require 'active_support/whiny_nil' rescue NameError # Rails < 1.1 require 'action_web_service' end Object.send(:remove_const, :RAILS_ROOT) end