Class: PhusionPassenger::ClassicRails::ApplicationSpawner

Class PhusionPassenger::ClassicRails::ApplicationSpawner |
In: | lib/phusion_passenger/classic_rails/application_spawner.rb
Parent: | AbstractServer

Spawning of Rails 1 and Rails 2 applications.

ClassicRails::ApplicationSpawner can operate in two modes:

- Smart mode. In this mode, the Rails application‘s code is first preloaded into a temporary process, which can then further fork off application processes. Once the code has been preloaded, forking off application processes is very fast, and all the forked off application processes can share code memory with each other. To use this mode, create an ApplicationSpawner object, start it, and call #spawn_application on it. A single ApplicationSpawner object can only handle a single Rails application.
- Conservative mode. In this mode, a Rails app process is directly spawned without any preloading. This increases compatibility with applications. To use this mode, call ApplicationSpawner.spawn_application.

Methods

- new
- spawn_application
- spawn_application
- start

Included Modules

- Utils
- DebugLogging

Classes and Modules
Class PhusionPassenger::ClassicRails::ApplicationSpawner::Error
Attributes

[R] | app_root | The application root of this spawner.

Public Class methods
new(options)

The following options are accepted:

- ‘app_root‘

See SpawnManager#spawn_application for information about the options.

[ show source ]

         # File lib/phusion_passenger/classic_rails/application_spawner.rb, line 116
    116:         def initialize(options)
    117:                 super()
    118:                 @options          = sanitize_spawn_options(options)
    119:                 @app_root         = @options["app_root"]
    120:                 @canonicalized_app_root = canonicalize_path(@app_root)
    121:                 self.max_idle_time = DEFAULT_APP_SPAWNER_MAX_IDLE_TIME
    122:                 define_message_handler(:spawn_application, :handle_spawn_application)
    123:         end

spawn_application(options)

Spawns an instance of a Rails application. When successful, an AppProcess object will be returned, which represents the spawned Rails application.

This method spawns the application directly, without preloading its code. This method may only be called if no Rails framework has been loaded in the current Ruby VM.

The "app_root" option must be given. All other options are passed to the request handler‘s constructor.

Raises:

- AppInitError: The Ruby on Rails application raised an exception or called exit() during startup.
- SystemCallError, IOError, SocketError: Something went wrong.

[ show source ]

         # File lib/phusion_passenger/classic_rails/application_spawner.rb, line 80
     80:         def self.spawn_application(options)
     81:                 options = sanitize_spawn_options(options)
     82:
     83:                 a, b = UNIXSocket.pair
     84:                 pid = safe_fork('application', true) do
     85:                         a.close
     86:
     87:                         file_descriptors_to_leave_open = [0, 1, 2, b.fileno]
     88:                         NativeSupport.close_all_file_descriptors(file_descriptors_to_leave_open)
     89:                         close_all_io_objects_for_fds(file_descriptors_to_leave_open)
     90:
     91:                         channel = MessageChannel.new(b)
     92:                         success = report_app_init_status(channel) do
     93:                                 prepare_app_process('config/environment.rb', options)
     94:                                 require File.expand_path('config/environment')
     95:                                 require 'dispatcher'
     96:                                 after_loading_app_code(options)
     97:                         end
     98:                         if success
     99:                                 start_request_handler(channel, false, options)
    100:                         end
    101:                 end
    102:                 b.close
    103:                 Process.waitpid(pid) rescue nil
    104:
    105:                 channel = MessageChannel.new(a)
    106:                 unmarshal_and_raise_errors(channel, options["print_exceptions"])
    107:
    108:                 # No exception was raised, so spawning succeeded.
    109:                 return AppProcess.read_from_channel(channel)
    110:         end

Public Instance methods
spawn_application(options = {})

Spawns an instance of the Rails application. When successful, an AppProcess object will be returned, which represents the spawned Rails application.

`options` will be passed to the request handler‘s constructor.

Raises:

- AbstractServer::ServerNotStarted: The ApplicationSpawner server hasn‘t already been started.
- ApplicationSpawner::Error: The ApplicationSpawner server exited unexpectedly.

[ show source ]

         # File lib/phusion_passenger/classic_rails/application_spawner.rb, line 133
    133:         def spawn_application(options = {})
    134:                 connect do |channel|
    135:                         channel.write("spawn_application", *options.to_a.flatten)
    136:                         return AppProcess.read_from_channel(channel)
    137:                 end
    138:         rescue SystemCallError, IOError, SocketError => e
    139:                 raise Error, "The application spawner server exited unexpectedly: #{e}"
    140:         end

start()

Overrided from AbstractServer#start.

May raise these additional exceptions:

- AppInitError: The Ruby on Rails application raised an exception or called exit() during startup.
- ApplicationSpawner::Error: The ApplicationSpawner server exited unexpectedly.

[ show source ]

         # File lib/phusion_passenger/classic_rails/application_spawner.rb, line 148
    148:         def start
    149:                 super
    150:                 begin
    151:                         channel = MessageChannel.new(@owner_socket)
    152:                         unmarshal_and_raise_errors(channel, @options["print_exceptions"])
    153:                 rescue IOError, SystemCallError, SocketError => e
    154:                         stop if started?
    155:                         raise Error, "The application spawner server exited unexpectedly: #{e}"
    156:                 rescue
    157:                         stop if started?
    158:                         raise
    159:                 end
    160:         end