Class: Rails::Application

Inherits:
Engine show all
Defined in:
lib/rails/application.rb,
lib/rails/application/finisher.rb,
lib/rails/application/bootstrap.rb,
lib/rails/application/configuration.rb,
lib/rails/application/routes_reloader.rb,
lib/rails/application/default_middleware_stack.rb

Overview

An Engine with the responsibility of coordinating the whole boot process.

Initialization

Rails::Application is responsible for executing all railties and engines initializers. It also executes some bootstrap initializers (check Rails::Application::Bootstrap) and finishing initializers, after all the others are executed (check Rails::Application::Finisher).

Configuration

Besides providing the same configuration as Rails::Engine and Rails::Railtie, the application object has several specific configurations, for example cache_classes, consider_all_requests_local, filter_parameters, logger, and so forth.

Check Rails::Application::Configuration to see them all.

Routes

The application object is also responsible for holding the routes and reloading routes whenever the files change in development.

Middlewares

The Application is also responsible for building the middleware stack.

Booting process

The application is also responsible for setting up and executing the booting process. From the moment you require config/application.rb in your app, the booting process goes like this:

  1. require "config/boot.rb" to set up load paths.

  2. require railties and engines.

  3. Define Rails.application as class MyApp::Application < Rails::Application.

  4. Run config.before_configuration callbacks.

  5. Load config/environments/ENV.rb.

  6. Run config.before_initialize callbacks.

  7. Run Railtie#initializer defined by railties, engines, and application. One by one, each engine sets up its load paths and routes, and runs its config/initializers/* files.

  8. Custom Railtie#initializers added by railties, engines, and applications are executed.

  9. Build the middleware stack and run to_prepare callbacks.

  10. Run config.before_eager_load and eager_load! if eager_load is true.

  11. Run config.after_initialize callbacks.

Defined Under Namespace

Modules: Bootstrap, Finisher Classes: Configuration, DefaultMiddlewareStack, RoutesReloader

Constant Summary collapse

INITIAL_VARIABLES = 
[:config, :railties, :routes_reloader, :reloaders,
:routes, :helpers, :app_env_config, :secrets]

Constants inherited from Railtie

Railtie::ABSTRACT_RAILTIES

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Methods inherited from Engine

#app, #call, endpoint, #endpoint, find, #helpers, isolate_namespace, #load_console, #load_generators, #load_runner, #load_seed, #load_server, #load_tasks, #railties, #routes, #routes?

Methods inherited from Railtie

<=>, abstract_railtie?, configure, #configure, console, generators, #inspect, railtie_name, #railtie_namespace, rake_tasks, runner, server, subclasses

Methods included from Initializable

included, #run_initializers

Constructor Details

#initialize(initial_variable_values = {}, &block) ⇒ Application

Returns a new instance of Application.



106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
 
# File 'lib/rails/application.rb', line 106

def initialize(initial_variable_values = {}, &block)
  super()
  @initialized       = false
  @reloaders         = []
  @routes_reloader   = nil
  @app_env_config    = nil
  @ordered_railties  = nil
  @railties          = nil
  @message_verifiers = {}
  @ran_load_hooks    = false

  @executor          = Class.new(ActiveSupport::Executor)
  @reloader          = Class.new(ActiveSupport::Reloader)
  @reloader.executor = @executor

  @autoloaders = Rails::Autoloaders.new

  # are these actually used?
  @initial_variable_values = initial_variable_values
  @block = block
end

Instance Attribute Details

#assets ⇒ Object

Returns the value of attribute assets.



97
98
99
 
# File 'lib/rails/application.rb', line 97

def assets
  @assets
end

#autoloaders ⇒ Object (readonly)

Returns the value of attribute autoloaders.



99
100
101
 
# File 'lib/rails/application.rb', line 99

def autoloaders
  @autoloaders
end

#config ⇒ Object

:nodoc:



383
384
385
 
# File 'lib/rails/application.rb', line 383

def config # :nodoc:
  @config ||= Application::Configuration.new(self.class.find_root(self.class.called_from))
end

#credentials ⇒ Object

Returns an ActiveSupport::EncryptedConfiguration instance for the credentials file specified by config.credentials.content_path.

By default, config.credentials.content_path will point to either config/credentials/#{environment}.yml.enc for the current environment (for example, config/credentials/production.yml.enc for the production environment), or config/credentials.yml.enc if that file does not exist.

The encryption key is taken from either ENV["RAILS_MASTER_KEY"], or from the file specified by config.credentials.key_path. By default, config.credentials.key_path will point to either config/credentials/#{environment}.key for the current environment, or config/master.key if that file does not exist.



439
440
441
 
# File 'lib/rails/application.rb', line 439

def credentials
  @credentials ||= encrypted(config.credentials.content_path, key_path: config.credentials.key_path)
end

#executor ⇒ Object (readonly)

Returns the value of attribute executor.



99
100
101
 
# File 'lib/rails/application.rb', line 99

def executor
  @executor
end

#reloader ⇒ Object (readonly)

Returns the value of attribute reloader.



99
100
101
 
# File 'lib/rails/application.rb', line 99

def reloader
  @reloader
end

#reloaders ⇒ Object (readonly)

Returns the value of attribute reloaders.



99
100
101
 
# File 'lib/rails/application.rb', line 99

def reloaders
  @reloaders
end

#sandbox ⇒ Object Also known as: sandbox?

Returns the value of attribute sandbox.



97
98
99
 
# File 'lib/rails/application.rb', line 97

def sandbox
  @sandbox
end

#secrets ⇒ Object 



389
390
391
392
393
394
395
396
397
398
399
400
401
 
# File 'lib/rails/application.rb', line 389

def secrets
  @secrets ||= begin
    secrets = ActiveSupport::OrderedOptions.new
    files = config.paths["config/secrets"].existent
    files = files.reject { |path| path.end_with?(".enc") } unless config.read_encrypted_secrets
    secrets.merge! Rails::Secrets.parse(files, env: Rails.env)

    # Fallback to config.secret_key_base if secrets.secret_key_base isn't set
    secrets.secret_key_base ||= config.secret_key_base

    secrets
  end
end

Class Method Details

.add_lib_to_load_path!(root) ⇒ Object

This method is called just after an application inherits from Rails::Application, allowing the developer to load classes in lib and use them during application configuration.

class MyApplication < Rails::Application
  require "my_backend" # in lib/my_backend
  config.i18n.backend = MyBackend
end

Notice this method takes into consideration the default root path. So if you are changing config.root inside your application definition or having a custom Rails application, you will need to add lib to $LOAD_PATH on your own in case you need to load files in lib/ during the application configuration as well.



339
340
341
342
343
344
 
# File 'lib/rails/application.rb', line 339

def self.add_lib_to_load_path!(root) # :nodoc:
  path = File.join root, "lib"
  if File.exist?(path) && !$LOAD_PATH.include?(path)
    $LOAD_PATH.unshift(path)
  end
end

.create(initial_variable_values = {}, &block) ⇒ Object 



81
82
83
 
# File 'lib/rails/application.rb', line 81

def create(initial_variable_values = {}, &block)
  new(initial_variable_values, &block).run_load_hooks!
end

.find_root(from) ⇒ Object 



85
86
87
 
# File 'lib/rails/application.rb', line 85

def find_root(from)
  find_root_with_flag "config.ru", from, Dir.pwd
end

.inherited(base) ⇒ Object 



70
71
72
73
74
75
 
# File 'lib/rails/application.rb', line 70

def inherited(base)
  super
  Rails.app_class = base
  add_lib_to_load_path!(find_root(base.called_from))
  ActiveSupport.run_load_hooks(:before_configuration, base)
end

.instance ⇒ Object 



77
78
79
 
# File 'lib/rails/application.rb', line 77

def instance
  super.run_load_hooks!
end

Instance Method Details

#config_for(name, env: Rails.env) ⇒ Object

Convenience for loading config/foo.yml for the current Rails env.

Examples:

# config/exception_notification.yml:
production:
  url: http://127.0.0.1:8080
  namespace: my_app_production

development:
  url: http://localhost:3001
  namespace: my_app_development

# config/environments/production.rb
Rails.application.configure do
  config.middleware.use ExceptionNotifier, config_for(:exception_notification)
end

# You can also store configurations in a shared section which will be
# merged with the environment configuration

# config/example.yml
shared:
  foo:
    bar:
      baz: 1

development:
  foo:
    bar:
      qux: 2

# development environment
Rails.application.config_for(:example)[:foo][:bar]
# => { baz: 1, qux: 2 }



221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
 
# File 'lib/rails/application.rb', line 221

def config_for(name, env: Rails.env)
  yaml = name.is_a?(Pathname) ? name : Pathname.new("#{paths["config"].existent.first}/#{name}.yml")

  if yaml.exist?
    require "erb"
    all_configs    = ActiveSupport::ConfigurationFile.parse(yaml).deep_symbolize_keys
    config, shared = all_configs[env.to_sym], all_configs[:shared]

    if shared
      config = {} if config.nil? && shared.is_a?(Hash)
      if config.is_a?(Hash) && shared.is_a?(Hash)
        config = shared.deep_merge(config)
      elsif config.nil?
        config = shared
      end
    end

    if config.is_a?(Hash)
      config = ActiveSupport::OrderedOptions.new.update(config)
    end

    config
  else
    raise "Could not load configuration. No such file - #{yaml}"
  end
end

#console(&blk) ⇒ Object

Sends any console called in the instance of a new application up to the console method defined in Rails::Railtie.



303
304
305
 
# File 'lib/rails/application.rb', line 303

def console(&blk)
  self.class.console(&blk)
end

#eager_load! ⇒ Object

Eager loads the application code.



492
493
494
 
# File 'lib/rails/application.rb', line 492

def eager_load!
  Rails.autoloaders.each(&:eager_load)
end

#encrypted(path, key_path: "config/master.key", env_key: "RAILS_MASTER_KEY") ⇒ Object

Returns an ActiveSupport::EncryptedConfiguration instance for an encrypted file. By default, the encryption key is taken from either ENV["RAILS_MASTER_KEY"], or from the config/master.key file.

my_config = Rails.application.encrypted("config/my_config.enc")

my_config.read
# => "foo:\n  bar: 123\n"

my_config.foo.bar
# => 123

Encrypted files can be edited with the bin/rails encrypted:edit command. (See the output of bin/rails encrypted:edit --help for more information.)



458
459
460
461
462
463
464
465
 
# File 'lib/rails/application.rb', line 458

def encrypted(path, key_path: "config/master.key", env_key: "RAILS_MASTER_KEY")
  ActiveSupport::EncryptedConfiguration.new(
    config_path: Rails.root.join(path),
    key_path: Rails.root.join(key_path),
    env_key: env_key,
    raise_if_missing_key: config.require_master_key
  )
end

#env_config ⇒ Object

Stores some of the Rails initial environment parameters which will be used by middlewares and engines to configure themselves.



250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
 
# File 'lib/rails/application.rb', line 250

def env_config
  @app_env_config ||= super.merge(
      "action_dispatch.parameter_filter" => config.filter_parameters,
      "action_dispatch.redirect_filter" => config.filter_redirect,
      "action_dispatch.secret_key_base" => secret_key_base,
      "action_dispatch.show_exceptions" => config.action_dispatch.show_exceptions,
      "action_dispatch.show_detailed_exceptions" => config.consider_all_requests_local,
      "action_dispatch.log_rescued_responses" => config.action_dispatch.log_rescued_responses,
      "action_dispatch.logger" => Rails.logger,
      "action_dispatch.backtrace_cleaner" => Rails.backtrace_cleaner,
      "action_dispatch.key_generator" => key_generator,
      "action_dispatch.http_auth_salt" => config.action_dispatch.http_auth_salt,
      "action_dispatch.signed_cookie_salt" => config.action_dispatch.signed_cookie_salt,
      "action_dispatch.encrypted_cookie_salt" => config.action_dispatch.encrypted_cookie_salt,
      "action_dispatch.encrypted_signed_cookie_salt" => config.action_dispatch.encrypted_signed_cookie_salt,
      "action_dispatch.authenticated_encrypted_cookie_salt" => config.action_dispatch.authenticated_encrypted_cookie_salt,
      "action_dispatch.use_authenticated_cookie_encryption" => config.action_dispatch.use_authenticated_cookie_encryption,
      "action_dispatch.encrypted_cookie_cipher" => config.action_dispatch.encrypted_cookie_cipher,
      "action_dispatch.signed_cookie_digest" => config.action_dispatch.signed_cookie_digest,
      "action_dispatch.cookies_serializer" => config.action_dispatch.cookies_serializer,
      "action_dispatch.cookies_digest" => config.action_dispatch.cookies_digest,
      "action_dispatch.cookies_rotations" => config.action_dispatch.cookies_rotations,
      "action_dispatch.cookies_same_site_protection" => coerce_same_site_protection(config.action_dispatch.cookies_same_site_protection),
      "action_dispatch.use_cookies_with_metadata" => config.action_dispatch.use_cookies_with_metadata,
      "action_dispatch.content_security_policy" => config.content_security_policy,
      "action_dispatch.content_security_policy_report_only" => config.content_security_policy_report_only,
      "action_dispatch.content_security_policy_nonce_generator" => config.content_security_policy_nonce_generator,
      "action_dispatch.content_security_policy_nonce_directives" => config.content_security_policy_nonce_directives,
      "action_dispatch.permissions_policy" => config.permissions_policy,
    )
end

#generators(&blk) ⇒ Object

Sends any generators called in the instance of a new application up to the generators method defined in Rails::Railtie.



309
310
311
 
# File 'lib/rails/application.rb', line 309

def generators(&blk)
  self.class.generators(&blk)
end

#helpers_paths ⇒ Object

:nodoc:



471
472
473
 
# File 'lib/rails/application.rb', line 471

def helpers_paths # :nodoc:
  config.helpers_paths
end

#initialize!(group = :default) ⇒ Object

Initialize the application passing the given group. By default, the group is :default



370
371
372
373
374
375
 
# File 'lib/rails/application.rb', line 370

def initialize!(group = :default) # :nodoc:
  raise "Application has been already initialized." if @initialized
  run_initializers(group, self)
  @initialized = true
  self
end

#initialized? ⇒ Boolean

Returns true if the application is initialized.

Returns:

  • (Boolean) 


129
130
131
 
# File 'lib/rails/application.rb', line 129

def initialized?
  @initialized
end

#initializer(name, opts = {}, &block) ⇒ Object

Sends the initializers to the initializer method defined in the Rails::Initializable module. Each Rails::Application class has its own set of initializers, as defined by the Initializable module.



291
292
293
 
# File 'lib/rails/application.rb', line 291

def initializer(name, opts = {}, &block)
  self.class.initializer(name, opts, &block)
end

#initializers ⇒ Object

:nodoc:



377
378
379
380
381
 
# File 'lib/rails/application.rb', line 377

def initializers # :nodoc:
  Bootstrap.initializers_for(self) +
  railties_initializers(super) +
  Finisher.initializers_for(self)
end

#isolate_namespace(mod) ⇒ Object

Sends the isolate_namespace method up to the class method.



320
321
322
 
# File 'lib/rails/application.rb', line 320

def isolate_namespace(mod)
  self.class.isolate_namespace(mod)
end

#key_generator ⇒ Object

Returns the application’s KeyGenerator



153
154
155
156
157
158
159
 
# File 'lib/rails/application.rb', line 153

def key_generator
  # number of iterations selected based on consultation with the google security
  # team. Details at https://github.com/rails/rails/pull/6952#issuecomment-7661220
  @caching_key_generator ||= ActiveSupport::CachingKeyGenerator.new(
    ActiveSupport::KeyGenerator.new(secret_key_base, iterations: 1000)
  )
end

#message_verifier(verifier_name) ⇒ Object

Returns a message verifier object.

This verifier can be used to generate and verify signed messages in the application.

It is recommended not to use the same verifier for different things, so you can get different verifiers passing the verifier_name argument.

Parameters

  • verifier_name - the name of the message verifier.

Examples

message = Rails.application.message_verifier('sensitive_data').generate('my sensible data')
Rails.application.message_verifier('sensitive_data').verify(message)
# => 'my sensible data'

See the ActiveSupport::MessageVerifier documentation for more information.



179
180
181
182
183
184
 
# File 'lib/rails/application.rb', line 179

def message_verifier(verifier_name)
  @message_verifiers[verifier_name] ||= begin
    secret = key_generator.generate_key(verifier_name.to_s)
    ActiveSupport::MessageVerifier.new(secret)
  end
end

#migration_railties ⇒ Object

Return an array of railties respecting the order they’re loaded and the order specified by the railties_order config.

While running initializers we need engines in reverse order here when copying migrations from railties ; we need them in the order given by railties_order.



487
488
489
 
# File 'lib/rails/application.rb', line 487

def migration_railties # :nodoc:
  ordered_railties.flatten - [self]
end

#rake_tasks(&block) ⇒ Object

If you try to define a set of Rake tasks on the instance, these will get passed up to the Rake tasks defined on the application’s class.



284
285
286
 
# File 'lib/rails/application.rb', line 284

def rake_tasks(&block)
  self.class.rake_tasks(&block)
end

#reload_routes! ⇒ Object

Reload application routes regardless if they changed or not.



148
149
150
 
# File 'lib/rails/application.rb', line 148

def reload_routes!
  routes_reloader.reload!
end

#require_environment! ⇒ Object

:nodoc:



346
347
348
349
 
# File 'lib/rails/application.rb', line 346

def require_environment! # :nodoc:
  environment = paths["config/environment"].existent.first
  require environment if environment
end

#routes_reloader ⇒ Object

:nodoc:



351
352
353
 
# File 'lib/rails/application.rb', line 351

def routes_reloader # :nodoc:
  @routes_reloader ||= RoutesReloader.new
end

#run_load_hooks! ⇒ Object

:nodoc:



133
134
135
136
137
138
139
140
141
142
143
144
145
 
# File 'lib/rails/application.rb', line 133

def run_load_hooks! # :nodoc:
  return self if @ran_load_hooks
  @ran_load_hooks = true

  @initial_variable_values.each do |variable_name, value|
    if INITIAL_VARIABLES.include?(variable_name)
      instance_variable_set("@#{variable_name}", value)
    end
  end

  instance_eval(&@block) if @block
  self
end

#runner(&blk) ⇒ Object

Sends any runner called in the instance of a new application up to the runner method defined in Rails::Railtie.



297
298
299
 
# File 'lib/rails/application.rb', line 297

def runner(&blk)
  self.class.runner(&blk)
end

#secret_key_base ⇒ Object

The secret_key_base is used as the input secret to the application’s key generator, which in turn is used to create all ActiveSupport::MessageVerifier and ActiveSupport::MessageEncryptor instances, including the ones that sign and encrypt cookies.

In development and test, this is randomly generated and stored in a temporary file in tmp/development_secret.txt.

In all other environments, we look for it first in ENV["SECRET_KEY_BASE"], then credentials.secret_key_base, and finally secrets.secret_key_base. For most applications, the correct place to store it is in the encrypted credentials file.



415
416
417
418
419
420
421
422
423
 
# File 'lib/rails/application.rb', line 415

def secret_key_base
  if Rails.env.development? || Rails.env.test?
    secrets.secret_key_base ||= generate_development_secret
  else
    validate_secret_key_base(
      ENV["SECRET_KEY_BASE"] || credentials.secret_key_base || secrets.secret_key_base
    )
  end
end

#server(&blk) ⇒ Object

Sends any server called in the instance of a new application up to the server method defined in Rails::Railtie.



315
316
317
 
# File 'lib/rails/application.rb', line 315

def server(&blk)
  self.class.server(&blk)
end

#to_app ⇒ Object

:nodoc:



467
468
469
 
# File 'lib/rails/application.rb', line 467

def to_app # :nodoc:
  self
end

#watchable_args ⇒ Object

Returns an array of file paths appended with a hash of directories-extensions suitable for ActiveSupport::FileUpdateChecker API.



358
359
360
361
362
363
364
365
366
 
# File 'lib/rails/application.rb', line 358

def watchable_args # :nodoc:
  files, dirs = config.watchable_files.dup, config.watchable_dirs.dup

  ActiveSupport::Dependencies.autoload_paths.each do |path|
    File.file?(path) ? files << path.to_s : dirs[path.to_s] = [:rb]
  end

  [files, dirs]
end