123456789_123456789_123456789_123456789_123456789_

Class: Rails::Application

Overview

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

Initialization

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

Configuration

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

Check 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 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.

Constant Summary

Railtie - Inherited

ABSTRACT_RAILTIES

::ActiveSupport::Callbacks - Included

CALLBACK_FILTER_TYPES

Class Attribute Summary

Engine - Inherited

.__callbacks, .called_from,
.isolated?

Alias for Engine.isolated.

Railtie - Inherited

.abstract_railtie?

Class Method Summary

Engine - Inherited

.endpoint, .engine_name,
.find

Finds engine with given path.
.find_root, .inherited, .isolate_namespace, .isolated, .new

Railtie - Inherited

.configure

Allows you to configure the railtie.
.console, .generators, .inherited,
.instance

Since Railtie cannot be instantiated, any methods that call .instance are intended to be called only on subclasses of a Railtie.
.railtie_name, .rake_tasks, .runner, .server, .subclasses

::ActiveSupport::DescendantsTracker - Extended

descendants

Instance Attribute Summary

Engine - Inherited

#__callbacks, #engine_name, #middleware, #paths, #root

Railtie - Inherited

#config

This is used to create the config object on Railties, an instance of Railtie::Configuration, that is used by Railties and Application to store related configuration.
#railtie_name

Instance Method Summary

Engine - Inherited

#app

Returns the underlying Rack application for this engine.
#call

Define the Rack API for this engine.
#config

Define the configuration object for the engine.
#eager_load!,
#endpoint

Returns the endpoint for this engine.
#env_config

Defines additional Rack env configuration that is added on each call.
#helpers

Returns a module with all the helpers defined for the engine.
#helpers_paths

Returns all registered helpers paths.
#isolated?,
#load_console

Load console and invoke the registered hooks.
#load_generators

Load Rails generators and invoke the registered hooks.
#load_runner

Load Rails runner and invoke the registered hooks.
#load_seed

Load data from db/seeds.rb file.
#load_server

Invoke the server registered hooks.
#load_tasks

Load Rake and railties tasks, and invoke the registered hooks.
#railties,
#routes

Defines the routes for this engine.
#load_config_initializer

::ActiveSupport::Callbacks - Included

#run_callbacks

Runs the callbacks for the given event.

Initializable - Included

#initializers, #run_initializers

Constructor Details

.new(initial_variable_values = {}, &block) ⇒ Application

[ GitHub ] 

  


# File 'railties/lib/rails/application.rb', line 109



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


  







Class Method Details



  

    .create(initial_variable_values = {}, &block)  
  

  [ GitHub ]


  

  


# File 'railties/lib/rails/application.rb', line 84



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


  








  

    .find_root(from)  
  

  [ GitHub ]


  

  


# File 'railties/lib/rails/application.rb', line 88



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


  








  

    .inherited(base)  
  

  [ GitHub ]


  

  


# File 'railties/lib/rails/application.rb', line 71



def inherited(base)
  super
  Rails.app_class = base
  # lib has to be added to $LOAD_PATH unconditionally, even if it's in the
  # autoload paths and config.add_autoload_paths_to_load_path is false.
  add_lib_to_load_path!(find_root(base.called_from))
  ActiveSupport.run_load_hooks(:before_configuration, base)
end


  








  

    .instance  
  

  [ GitHub ]


  

  


# File 'railties/lib/rails/application.rb', line 80



def instance
  super.run_load_hooks!
end


  







Instance Attribute Details



  

    #assets   (rw)
  

  [ GitHub ]


  

  


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



attr_accessor :assets, :sandbox


  








  

    #autoloaders   (readonly)
  

  [ GitHub ]


  

  


# File 'railties/lib/rails/application.rb', line 102



attr_reader :reloaders, :reloader, :executor, :autoloaders


  








  

    #config=(value)   (rw)
  

  [ GitHub ]


  

  


# File 'railties/lib/rails/application.rb', line 455



attr_writer :config


  








  

    #credentials   (rw)
  



  

    

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.


  



  [ GitHub ]


  

  


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



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


  








  

    #credentials=(value)   (rw)
  

  [ GitHub ]


  

  


# File 'railties/lib/rails/application.rb', line 456



attr_writer :credentials


  








  

    #default_url_options   (rw)
  

  [ GitHub ]


  

  


# File 'railties/lib/rails/application.rb', line 104



delegate :default_url_options, :default_url_options=, to: :routes


  








  

    #executor   (readonly)
  

  [ GitHub ]


  

  


# File 'railties/lib/rails/application.rb', line 102



attr_reader :reloaders, :reloader, :executor, :autoloaders


  








  

    #initialized?  ⇒ Boolean  (readonly)
  



  

    

Returns true if the application is initialized.


  





  


  [ GitHub ]


  

  


# File 'railties/lib/rails/application.rb', line 134



def initialized?
  @initialized
end


  








  

    #reloader   (readonly)
  

  [ GitHub ]


  

  


# File 'railties/lib/rails/application.rb', line 102



attr_reader :reloaders, :reloader, :executor, :autoloaders


  








  

    #reloaders   (readonly)
  

  [ GitHub ]


  

  


# File 'railties/lib/rails/application.rb', line 102



attr_reader :reloaders, :reloader, :executor, :autoloaders


  








  

    #sandbox?   (rw)
  



  

    

Alias for #sandbox.


  



  [ GitHub ]


  

  


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



alias_method :sandbox?, :sandbox


  







Instance Method Details



  

    #config_for(name, env: Rails.env)  
  



  

    

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



# config/exception_notification.yml:
production:
  url: http://127.0:8080
  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 }


  



  [ GitHub ]


  

  


# File 'railties/lib/rails/application.rb', line 288



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)  
  



  

    

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


  



  [ GitHub ]


  

  


# File 'railties/lib/rails/application.rb', line 371



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


  








  

    #deprecators  
  



  

    

A managed collection of deprecators (ActiveSupport::Deprecation::Deprecators). The collection’s configuration methods affect all deprecators in the collection. Additionally, the collection’s silence method silences all deprecators in the collection for the duration of a given block.


  



  [ GitHub ]


  

  


# File 'railties/lib/rails/application.rb', line 244



def deprecators
  @deprecators ||= ActiveSupport::Deprecation::Deprecators.new.tap do |deprecators|
    deprecators[:railties] = Rails.deprecator
  end
end


  








  

    #eager_load!  
  



  

    

Eager loads the application code.


  



  [ GitHub ]


  

  


# File 'railties/lib/rails/application.rb', line 550



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


  








  

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



  

    

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.)


  



  [ GitHub ]


  

  


# File 'railties/lib/rails/application.rb', line 511



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  
  



  

    

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


  



  [ GitHub ]


  

  


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



def env_config
  @app_env_config ||= super.merge(
      "action_dispatch.parameter_filter" => 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.debug_exception_log_level" => ActiveSupport::Logger.const_get(config.action_dispatch.debug_exception_log_level.to_s.upcase),
      "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)  
  



  

    

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


  



  [ GitHub ]


  

  


# File 'railties/lib/rails/application.rb', line 377



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


  








  

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



  

    

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


  



  [ GitHub ]


  

  


# File 'railties/lib/rails/application.rb', line 359



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


  








  

    #isolate_namespace(mod)  
  



  

    

Sends the isolate_namespace method up to the class method.


  



  [ GitHub ]


  

  


# File 'railties/lib/rails/application.rb', line 388



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


  








  

    #key_generator(secret_key_base = self.secret_key_base)  
  



  

    

Returns a key generator (ActiveSupport::CachingKeyGenerator) for a specified #secret_key_base. The return value is memoized, so additional calls with the same #secret_key_base will return the same key generator instance.


  



  [ GitHub ]


  

  


# File 'railties/lib/rails/application.rb', line 172



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


  








  

    #message_verifier(verifier_name)  
  



  

    

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.



For instance, ActiveStorage::Blob.signed_id_verifier is implemented using this feature, which assures that the IDs strings haven’t been tampered with and are safe to use in a finder.



See the ::ActiveSupport::MessageVerifier documentation for more information.



Parameters


  • 

    verifier_name - the name of the message verifier.
    




Examples



message = Rails.application.message_verifier('my_purpose').generate('data to sign against tampering')
Rails.application.message_verifier('my_purpose').verify(message)
# => 'data to sign against tampering'


  



  [ GitHub ]


  

  


# File 'railties/lib/rails/application.rb', line 236



def message_verifier(verifier_name)
  message_verifiers[verifier_name]
end


  








  

    #message_verifiers  
  



  

    

Returns a message verifier factory (ActiveSupport::MessageVerifiers). This factory can be used as a central point to configure and create message verifiers (ActiveSupport::MessageVerifier) for your application.



By default, message verifiers created by this factory will generate messages using the default ::ActiveSupport::MessageVerifier options. You can override these options with a combination of ActiveSupport::MessageVerifiers#clear_rotations and ActiveSupport::MessageVerifiers#rotate. However, this must be done prior to building any message verifier instances. For example, in a before_initialize block:



# Use `url_safe: true` when generating messages
config.before_initialize do |app|
  app.message_verifiers.clear_rotations
  app.message_verifiers.rotate(url_safe: true)
end



Message verifiers created by this factory will always use a secret derived from #secret_key_base when generating messages. clear_rotations will not affect this behavior. However, older #secret_key_base values can be rotated for verifying messages:



# Fall back to old {secret_key_base} when verifying messages
config.before_initialize do |app|
  app.message_verifiers.rotate(secret_key_base: "old secret_key_base")
end


  



  [ GitHub ]


  

  


# File 'railties/lib/rails/application.rb', line 208



def message_verifiers
  @message_verifiers ||=
    ActiveSupport::MessageVerifiers.new do |salt, secret_key_base: self.secret_key_base|
      key_generator(secret_key_base).generate_key(salt)
    end.rotate_defaults
end


  








  

    #name  
  



  

    

Returns the dasherized application name.



MyApp::Application.new.name => "my-app"


  



  [ GitHub ]


  

  


# File 'railties/lib/rails/application.rb', line 141



def name
  self.class.name.underscore.dasherize.delete_suffix("/application")
end


  








  

    #rake_tasks(&block)  
  



  

    

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.


  



  [ GitHub ]


  

  


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



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


  








  

    #reload_routes!  
  



  

    

Reload application routes regardless if they changed or not.


  



  [ GitHub ]


  

  


# File 'railties/lib/rails/application.rb', line 160



def reload_routes!
  routes_reloader.reload!
end


  








  

    #runner(&blk)  
  



  

    

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


  



  [ GitHub ]


  

  


# File 'railties/lib/rails/application.rb', line 365



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


  








  

    #sandbox   (rw)
    Also known as: #sandbox?
  

  [ GitHub ]


  

  


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



attr_accessor :assets, :sandbox


  








  

    #secret_key_base  
  



  

    

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/local_secret.txt.



You can also set ENV["SECRET_KEY_BASE_DUMMY"] to trigger the use of a randomly generated secret_key_base that’s stored in a temporary file. This is useful when precompiling assets for production as part of a build step that otherwise does not need access to the production secrets.



Dockerfile example: RUN SECRET_KEY_BASE_DUMMY=1 bundle exec rails assets:precompile.



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


  



  [ GitHub ]


  

  


# File 'railties/lib/rails/application.rb', line 474



def secret_key_base
  config.secret_key_base
end


  








  

    #server(&blk)  
  



  

    

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


  



  [ GitHub ]


  

  


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



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