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diff --git a/guides/source/configuring.md b/guides/source/configuring.md index e80f994deb..e1c9fad232 100644 --- a/guides/source/configuring.md +++ b/guides/source/configuring.md @@ -1,4 +1,4 @@ -**DO NOT READ THIS FILE ON GITHUB, GUIDES ARE PUBLISHED ON http://guides.rubyonrails.org.** +**DO NOT READ THIS FILE ON GITHUB, GUIDES ARE PUBLISHED ON https://guides.rubyonrails.org.** Configuring Rails Applications ============================== @@ -32,7 +32,7 @@ Configuring Rails Components In general, the work of configuring Rails means configuring the components of Rails, as well as configuring Rails itself. The configuration file `config/application.rb` and environment-specific configuration files (such as `config/environments/production.rb`) allow you to specify the various settings that you want to pass down to all of the components. -For example, the `config/application.rb` file includes this setting: +For example, you could add this setting to `config/application.rb` file: ```ruby config.time_zone = 'Central Time (US & Canada)' @@ -60,22 +60,20 @@ These configuration methods are to be called on a `Rails::Railtie` object, such * `config.asset_host` sets the host for the assets. Useful when CDNs are used for hosting assets, or when you want to work around the concurrency constraints built-in in browsers using different domain aliases. Shorter version of `config.action_controller.asset_host`. -* `config.autoload_once_paths` accepts an array of paths from which Rails will autoload constants that won't be wiped per request. Relevant if `config.cache_classes` is false, which is the case in development mode by default. Otherwise, all autoloading happens only once. All elements of this array must also be in `autoload_paths`. Default is an empty array. +* `config.autoload_once_paths` accepts an array of paths from which Rails will autoload constants that won't be wiped per request. Relevant if `config.cache_classes` is `false`, which is the case in development mode by default. Otherwise, all autoloading happens only once. All elements of this array must also be in `autoload_paths`. Default is an empty array. -* `config.autoload_paths` accepts an array of paths from which Rails will autoload constants. Default is all directories under `app`. +* `config.autoload_paths` accepts an array of paths from which Rails will autoload constants. Default is all directories under `app`. It is no longer recommended to adjust this. See [Autoloading and Reloading Constants](autoloading_and_reloading_constants.html#autoload-paths-and-eager-load-paths) -* `config.cache_classes` controls whether or not application classes and modules should be reloaded on each request. Defaults to false in development mode, and true in test and production modes. - -* `config.action_view.cache_template_loading` controls whether or not templates should be reloaded on each request. Defaults to whatever is set for `config.cache_classes`. +* `config.cache_classes` controls whether or not application classes and modules should be reloaded on each request. Defaults to `false` in development mode, and `true` in test and production modes. * `config.beginning_of_week` sets the default beginning of week for the application. Accepts a valid week day symbol (e.g. `:monday`). -* `config.cache_store` configures which cache store to use for Rails caching. Options include one of the symbols `:memory_store`, `:file_store`, `:mem_cache_store`, `:null_store`, or an object that implements the cache API. Defaults to `:file_store` if the directory `tmp/cache` exists, and to `:memory_store` otherwise. +* `config.cache_store` configures which cache store to use for Rails caching. Options include one of the symbols `:memory_store`, `:file_store`, `:mem_cache_store`, `:null_store`, `:redis_cache_store`, or an object that implements the cache API. Defaults to `:file_store`. -* `config.colorize_logging` specifies whether or not to use ANSI color codes when logging information. Defaults to true. +* `config.colorize_logging` specifies whether or not to use ANSI color codes when logging information. Defaults to `true`. -* `config.consider_all_requests_local` is a flag. If true then any error will cause detailed debugging information to be dumped in the HTTP response, and the `Rails::Info` controller will show the application runtime context in `/rails/info/properties`. True by default in development and test environments, and false in production mode. For finer-grained control, set this to false and implement `local_request?` in controllers to specify which requests should provide debugging information on errors. +* `config.consider_all_requests_local` is a flag. If `true` then any error will cause detailed debugging information to be dumped in the HTTP response, and the `Rails::Info` controller will show the application runtime context in `/rails/info/properties`. `true` by default in development and test environments, and `false` in production mode. For finer-grained control, set this to `false` and implement `local_request?` in controllers to specify which requests should provide debugging information on errors. * `config.console` allows you to set class that will be used as console you run `rails console`. It's best to run it in `console` block: @@ -88,27 +86,31 @@ application. Accepts a valid week day symbol (e.g. `:monday`). end ``` -* `config.eager_load` when true, eager loads all registered `config.eager_load_namespaces`. This includes your application, engines, Rails frameworks and any other registered namespace. +* `config.disable_sandbox` controls whether or not someone can start a console in sandbox mode. This is helpful to avoid a long running session of sandbox console, that could lead a database server to run out of memory. Defaults to false. -* `config.eager_load_namespaces` registers namespaces that are eager loaded when `config.eager_load` is true. All namespaces in the list must respond to the `eager_load!` method. +* `config.eager_load` when `true`, eager loads all registered `config.eager_load_namespaces`. This includes your application, engines, Rails frameworks, and any other registered namespace. + +* `config.eager_load_namespaces` registers namespaces that are eager loaded when `config.eager_load` is `true`. All namespaces in the list must respond to the `eager_load!` method. * `config.eager_load_paths` accepts an array of paths from which Rails will eager load on boot if cache classes is enabled. Defaults to every folder in the `app` directory of the application. +* `config.enable_dependency_loading`: when true, enables autoloading, even if the application is eager loaded and `config.cache_classes` is set as true. Defaults to false. + * `config.encoding` sets up the application-wide encoding. Defaults to UTF-8. * `config.exceptions_app` sets the exceptions application invoked by the ShowException middleware when an exception happens. Defaults to `ActionDispatch::PublicExceptions.new(Rails.public_path)`. -* `config.debug_exception_response_format` sets the format used in responses when errors occur in development mode. +* `config.debug_exception_response_format` sets the format used in responses when errors occur in development mode. Defaults to `:api` for API only apps and `:default` for normal apps. -* `config.file_watcher` is the class used to detect file updates in the file system when `config.reload_classes_only_on_change` is true. Rails ships with `ActiveSupport::FileUpdateChecker`, the default, and `ActiveSupport::EventedFileUpdateChecker` (this one depends on the [listen](https://github.com/guard/listen) gem). Custom classes must conform to the `ActiveSupport::FileUpdateChecker` API. +* `config.file_watcher` is the class used to detect file updates in the file system when `config.reload_classes_only_on_change` is `true`. Rails ships with `ActiveSupport::FileUpdateChecker`, the default, and `ActiveSupport::EventedFileUpdateChecker` (this one depends on the [listen](https://github.com/guard/listen) gem). Custom classes must conform to the `ActiveSupport::FileUpdateChecker` API. * `config.filter_parameters` used for filtering out the parameters that you don't want shown in the logs, such as passwords or credit card -numbers. New applications filter out passwords by adding the following `config.filter_parameters+=[:password]` in `config/initializers/filter_parameter_logging.rb`. Parameters filter works by partial matching regular expression. +numbers. It also filters out sensitive values of database columns when call `#inspect` on an Active Record object. By default, Rails filters out passwords by adding `Rails.application.config.filter_parameters += [:password]` in `config/initializers/filter_parameter_logging.rb`. Parameters filter works by partial matching regular expression. -* `config.force_ssl` forces all requests to be served over HTTPS by using the `ActionDispatch::SSL` middleware, and sets `config.action_mailer.default_url_options` to be `{ protocol: 'https' }`. This can be configured by setting `config.ssl_options` - see the [ActionDispatch::SSL documentation](http://edgeapi.rubyonrails.org/classes/ActionDispatch/SSL.html) for details. +* `config.force_ssl` forces all requests to be served over HTTPS by using the `ActionDispatch::SSL` middleware, and sets `config.action_mailer.default_url_options` to be `{ protocol: 'https' }`. This can be configured by setting `config.ssl_options` - see the [ActionDispatch::SSL documentation](https://api.rubyonrails.org/classes/ActionDispatch/SSL.html) for details. -* `config.log_formatter` defines the formatter of the Rails logger. This option defaults to an instance of `ActiveSupport::Logger::SimpleFormatter` for all modes except production, where it defaults to `Logger::Formatter`. If you are setting a value for `config.logger` you must manually pass the value of your formatter to your logger before it is wrapped in an `ActiveSupport::TaggedLogging` instance, Rails will not do it for you. +* `config.log_formatter` defines the formatter of the Rails logger. This option defaults to an instance of `ActiveSupport::Logger::SimpleFormatter` for all modes. If you are setting a value for `config.logger` you must manually pass the value of your formatter to your logger before it is wrapped in an `ActiveSupport::TaggedLogging` instance, Rails will not do it for you. * `config.log_level` defines the verbosity of the Rails logger. This option defaults to `:debug` for all environments. The available log levels are: `:debug`, @@ -116,31 +118,34 @@ defaults to `:debug` for all environments. The available log levels are: `:debug * `config.log_tags` accepts a list of: methods that the `request` object responds to, a `Proc` that accepts the `request` object, or something that responds to `to_s`. This makes it easy to tag log lines with debug information like subdomain and request id - both very helpful in debugging multi-user production applications. -* `config.logger` is the logger that will be used for `Rails.logger` and any related Rails logging such as `ActiveRecord::Base.logger`. It defaults to an instance of `ActiveSupport::TaggedLogging` that wraps an instance of `ActiveSupport::Logger` which outputs a log to the `log/` directory. You can supply a custom logger, to get full compatability you must follow these guidelines: - * To support a formatter you must manually assign a formatter from the `config.log_formatter` value to the logger. - * To support tagged loggs the log instance must be wrapped with `ActiveSupport::TaggedLogging`. - * To support silencing the logger must include `LoggerSilence` and `ActiveSupport::LoggerThreadSafeLevel` modules. The `ActiveSupport::Logger` class already includes these modules. +* `config.logger` is the logger that will be used for `Rails.logger` and any related Rails logging such as `ActiveRecord::Base.logger`. It defaults to an instance of `ActiveSupport::TaggedLogging` that wraps an instance of `ActiveSupport::Logger` which outputs a log to the `log/` directory. You can supply a custom logger, to get full compatibility you must follow these guidelines: + * To support a formatter, you must manually assign a formatter from the `config.log_formatter` value to the logger. + * To support tagged logs, the log instance must be wrapped with `ActiveSupport::TaggedLogging`. + * To support silencing, the logger must include `ActiveSupport::LoggerSilence` module. The `ActiveSupport::Logger` class already includes these modules. ```ruby class MyLogger < ::Logger - include ActiveSupport::LoggerThreadSafeLevel - include LoggerSilence + include ActiveSupport::LoggerSilence end mylogger = MyLogger.new(STDOUT) mylogger.formatter = config.log_formatter - config.logger = ActiveSupport::TaggedLogging.new(mylogger) + config.logger = ActiveSupport::TaggedLogging.new(mylogger) ``` * `config.middleware` allows you to configure the application's middleware. This is covered in depth in the [Configuring Middleware](#configuring-middleware) section below. -* `config.reload_classes_only_on_change` enables or disables reloading of classes only when tracked files change. By default tracks everything on autoload paths and is set to true. If `config.cache_classes` is true, this option is ignored. +* `config.reload_classes_only_on_change` enables or disables reloading of classes only when tracked files change. By default tracks everything on autoload paths and is set to `true`. If `config.cache_classes` is `true`, this option is ignored. -* `secrets.secret_key_base` is used for specifying a key which allows sessions for the application to be verified against a known secure key to prevent tampering. Applications get `secrets.secret_key_base` initialized to a random key present in `config/secrets.yml`. +* `config.credentials.content_path` configures lookup path for encrypted credentials. -* `config.public_file_server.enabled` configures Rails to serve static files from the public directory. This option defaults to true, but in the production environment it is set to false because the server software (e.g. NGINX or Apache) used to run the application should serve static files instead. If you are running or testing your app in production mode using WEBrick (it is not recommended to use WEBrick in production) set the option to true. Otherwise, you won't be able to use page caching and request for files that exist under the public directory. +* `config.credentials.key_path` configures lookup path for encryption key. -* `config.session_store` is usually set up in `config/initializers/session_store.rb` and specifies what class to use to store the session. Possible values are `:cookie_store` which is the default, `:mem_cache_store`, and `:disabled`. The last one tells Rails not to deal with sessions. Custom session stores can also be specified: +* `secret_key_base` is used for specifying a key which allows sessions for the application to be verified against a known secure key to prevent tampering. Applications get a random generated key in test and development environments, other environments should set one in `config/credentials.yml.enc`. + +* `config.public_file_server.enabled` configures Rails to serve static files from the public directory. This option defaults to `true`, but in the production environment it is set to `false` because the server software (e.g. NGINX or Apache) used to run the application should serve static files instead. If you are running or testing your app in production mode using WEBrick (it is not recommended to use WEBrick in production) set the option to `true.` Otherwise, you won't be able to use page caching and request for files that exist under the public directory. + +* `config.session_store` specifies what class to use to store the session. Possible values are `:cookie_store` which is the default, `:mem_cache_store`, and `:disabled`. The last one tells Rails not to deal with sessions. Defaults to a cookie store with application name as the session key. Custom session stores can also be specified: ```ruby config.session_store :my_custom_store @@ -153,31 +158,35 @@ defaults to `:debug` for all environments. The available log levels are: `:debug ### Configuring Assets * `config.assets.enabled` a flag that controls whether the asset -pipeline is enabled. It is set to true by default. - -* `config.assets.raise_runtime_errors` Set this flag to `true` to enable additional runtime error checking. Recommended in `config/environments/development.rb` to minimize unexpected behavior when deploying to `production`. - -* `config.assets.compress` a flag that enables the compression of compiled assets. It is explicitly set to true in `config/environments/production.rb`. +pipeline is enabled. It is set to `true` by default. * `config.assets.css_compressor` defines the CSS compressor to use. It is set by default by `sass-rails`. The unique alternative value at the moment is `:yui`, which uses the `yui-compressor` gem. * `config.assets.js_compressor` defines the JavaScript compressor to use. Possible values are `:closure`, `:uglifier` and `:yui` which require the use of the `closure-compiler`, `uglifier` or `yui-compressor` gems respectively. +* `config.assets.gzip` a flag that enables the creation of gzipped version of compiled assets, along with non-gzipped assets. Set to `true` by default. + * `config.assets.paths` contains the paths which are used to look for assets. Appending paths to this configuration option will cause those paths to be used in the search for assets. * `config.assets.precompile` allows you to specify additional assets (other than `application.css` and `application.js`) which are to be precompiled when `rake assets:precompile` is run. +* `config.assets.unknown_asset_fallback` allows you to modify the behavior of the asset pipeline when an asset is not in the pipeline, if you use sprockets-rails 3.2.0 or newer. Defaults to `false`. + * `config.assets.prefix` defines the prefix where assets are served from. Defaults to `/assets`. * `config.assets.manifest` defines the full path to be used for the asset precompiler's manifest file. Defaults to a file named `manifest-<random>.json` in the `config.assets.prefix` directory within the public folder. -* `config.assets.digest` enables the use of MD5 fingerprints in asset names. Set to `true` by default. +* `config.assets.digest` enables the use of SHA256 fingerprints in asset names. Set to `true` by default. * `config.assets.debug` disables the concatenation and compression of assets. Set to `true` by default in `development.rb`. +* `config.assets.version` is an option string that is used in SHA256 hash generation. This can be changed to force all files to be recompiled. + * `config.assets.compile` is a boolean that can be used to turn on live Sprockets compilation in production. -* `config.assets.logger` accepts a logger conforming to the interface of Log4r or the default Ruby `Logger` class. Defaults to the same configured at `config.logger`. Setting `config.assets.logger` to false will turn off served assets logging. +* `config.assets.logger` accepts a logger conforming to the interface of Log4r or the default Ruby `Logger` class. Defaults to the same configured at `config.logger`. Setting `config.assets.logger` to `false` will turn off served assets logging. + +* `config.assets.quiet` disables logging of assets requests. Set to `true` by default in `development.rb`. ### Configuring Generators @@ -196,8 +205,7 @@ The full set of methods that can be used in this block are as follows: * `force_plural` allows pluralized model names. Defaults to `false`. * `helper` defines whether or not to generate helpers. Defaults to `true`. * `integration_tool` defines which integration tool to use to generate integration tests. Defaults to `:test_unit`. -* `javascripts` turns on the hook for JavaScript files in generators. Used in Rails for when the `scaffold` generator is run. Defaults to `true`. -* `javascript_engine` configures the engine to be used (for eg. coffee) when generating assets. Defaults to `:js`. +* `system_tests` defines which integration tool to use to generate system tests. Defaults to `:test_unit`. * `orm` defines which orm to use. Defaults to `false` and will use Active Record by default. * `resource_controller` defines which generator to use for generating a controller when using `rails generate resource`. Defaults to `:controller`. * `resource_route` defines whether a resource route definition should be generated @@ -206,7 +214,7 @@ The full set of methods that can be used in this block are as follows: * `stylesheets` turns on the hook for stylesheets in generators. Used in Rails for when the `scaffold` generator is run, but this hook can be used in other generates as well. Defaults to `true`. * `stylesheet_engine` configures the stylesheet engine (for eg. sass) to be used when generating assets. Defaults to `:css`. * `scaffold_stylesheet` creates `scaffold.css` when generating a scaffolded resource. Defaults to `true`. -* `test_framework` defines which test framework to use. Defaults to `false` and will use Minitest by default. +* `test_framework` defines which test framework to use. Defaults to `false` and will use minitest by default. * `template_engine` defines which template engine to use, such as ERB or Haml. Defaults to `:erb`. ### Configuring Middleware @@ -215,7 +223,7 @@ Every Rails application comes with a standard set of middleware which it uses in * `ActionDispatch::SSL` forces every request to be served using HTTPS. Enabled if `config.force_ssl` is set to `true`. Options passed to this can be configured by setting `config.ssl_options`. * `ActionDispatch::Static` is used to serve static assets. Disabled if `config.public_file_server.enabled` is `false`. Set `config.public_file_server.index_name` if you need to serve a static directory index file that is not named `index`. For example, to serve `main.html` instead of `index.html` for directory requests, set `config.public_file_server.index_name` to `"main"`. -* `ActionDispatch::LoadInterlock` allows thread safe code reloading. Disabled if `config.allow_concurrency` is `false`, which causes `Rack::Lock` to be loaded. `Rack::Lock` wraps the app in mutex so it can only be called by a single thread at a time. +* `ActionDispatch::Executor` allows thread safe code reloading. Disabled if `config.allow_concurrency` is `false`, which causes `Rack::Lock` to be loaded. `Rack::Lock` wraps the app in mutex so it can only be called by a single thread at a time. * `ActiveSupport::Cache::Strategy::LocalCache` serves as a basic memory backed cache. This cache is not thread safe and is intended only for serving as a temporary memory cache for a single thread. * `Rack::Runtime` sets an `X-Runtime` header, containing the time (in seconds) taken to execute the request. * `Rails::Rack::Logger` notifies the logs that the request has begun. After request is complete, flushes all the logs. @@ -224,8 +232,6 @@ Every Rails application comes with a standard set of middleware which it uses in * `ActionDispatch::RemoteIp` checks for IP spoofing attacks and gets valid `client_ip` from request headers. Configurable with the `config.action_dispatch.ip_spoofing_check`, and `config.action_dispatch.trusted_proxies` options. * `Rack::Sendfile` intercepts responses whose body is being served from a file and replaces it with a server specific X-Sendfile header. Configurable with `config.action_dispatch.x_sendfile_header`. * `ActionDispatch::Callbacks` runs the prepare callbacks before serving the request. -* `ActiveRecord::ConnectionAdapters::ConnectionManagement` cleans active connections after each request, unless the `rack.test` key in the request environment is set to `true`. -* `ActiveRecord::QueryCache` caches all SELECT queries generated in a request. If any INSERT or UPDATE takes place then the cache is cleaned. * `ActionDispatch::Cookies` sets cookies for the request. * `ActionDispatch::Session::CookieStore` is responsible for storing the session in cookies. An alternate middleware can be used for this by changing the `config.action_controller.session_store` to an alternate value. Additionally, options passed to this can be configured by using `config.action_controller.session_options`. * `ActionDispatch::Flash` sets up the `flash` keys. Only available if `config.action_controller.session_store` is set to a value. @@ -244,6 +250,12 @@ This will put the `Magical::Unicorns` middleware on the end of the stack. You ca config.middleware.insert_before Rack::Head, Magical::Unicorns ``` +Or you can insert a middleware to exact position by using indexes. For example, if you want to insert `Magical::Unicorns` middleware on top of the stack, you can do it, like so: + +```ruby +config.middleware.insert_before 0, Magical::Unicorns +``` + There's also `insert_after` which will insert a middleware after another: ```ruby @@ -266,7 +278,7 @@ config.middleware.delete Rack::MethodOverride All these configuration options are delegated to the `I18n` library. -* `config.i18n.available_locales` whitelists the available locales for the app. Defaults to all locale keys found in locale files, usually only `:en` on a new application. +* `config.i18n.available_locales` defines the permitted available locales for the app. Defaults to all locale keys found in locale files, usually only `:en` on a new application. * `config.i18n.default_locale` sets the default locale of an application used for i18n. Defaults to `:en`. @@ -274,6 +286,32 @@ All these configuration options are delegated to the `I18n` library. * `config.i18n.load_path` sets the path Rails uses to look for locale files. Defaults to `config/locales/*.{yml,rb}`. +* `config.i18n.fallbacks` sets fallback behavior for missing translations. Here are 3 usage examples for this option: + + * You can set the option to `true` for using default locale as fallback, like so: + + ```ruby + config.i18n.fallbacks = true + ``` + + * Or you can set an array of locales as fallback, like so: + + ```ruby + config.i18n.fallbacks = [:tr, :en] + ``` + + * Or you can set different fallbacks for locales individually. For example, if you want to use `:tr` for `:az` and `:de`, `:en` for `:da` as fallbacks, you can do it, like so: + + ```ruby + config.i18n.fallbacks = { az: :tr, da: [:de, :en] } + #or + config.i18n.fallbacks.map = { az: :tr, da: [:de, :en] } + ``` + +### Configuring Active Model + +* `config.active_model.i18n_customize_full_message` is a boolean value which controls whether the `full_message` error format can be overridden at the attribute or model level in the locale files. This is `false` by default. + ### Configuring Active Record `config.active_record` includes a variety of configuration options: @@ -281,8 +319,8 @@ All these configuration options are delegated to the `I18n` library. * `config.active_record.logger` accepts a logger conforming to the interface of Log4r or the default Ruby Logger class, which is then passed on to any new database connections made. You can retrieve this logger by calling `logger` on either an Active Record model class or an Active Record model instance. Set to `nil` to disable logging. * `config.active_record.primary_key_prefix_type` lets you adjust the naming for primary key columns. By default, Rails assumes that primary key columns are named `id` (and this configuration option doesn't need to be set.) There are two other choices: - * `:table_name` would make the primary key for the Customer class `customerid` - * `:table_name_with_underscore` would make the primary key for the Customer class `customer_id` + * `:table_name` would make the primary key for the Customer class `customerid`. + * `:table_name_with_underscore` would make the primary key for the Customer class `customer_id`. * `config.active_record.table_name_prefix` lets you set a global string to be prepended to table names. If you set this to `northwest_`, then the Customer class will look for `northwest_customers` as its table. The default is an empty string. @@ -290,17 +328,21 @@ All these configuration options are delegated to the `I18n` library. * `config.active_record.schema_migrations_table_name` lets you set a string to be used as the name of the schema migrations table. -* `config.active_record.pluralize_table_names` specifies whether Rails will look for singular or plural table names in the database. If set to true (the default), then the Customer class will use the `customers` table. If set to false, then the Customer class will use the `customer` table. +* `config.active_record.internal_metadata_table_name` lets you set a string to be used as the name of the internal metadata table. + +* `config.active_record.protected_environments` lets you set an array of names of environments where destructive actions should be prohibited. + +* `config.active_record.pluralize_table_names` specifies whether Rails will look for singular or plural table names in the database. If set to `true` (the default), then the Customer class will use the `customers` table. If set to false, then the Customer class will use the `customer` table. * `config.active_record.default_timezone` determines whether to use `Time.local` (if set to `:local`) or `Time.utc` (if set to `:utc`) when pulling dates and times from the database. The default is `:utc`. * `config.active_record.schema_format` controls the format for dumping the database schema to a file. The options are `:ruby` (the default) for a database-independent version that depends on migrations, or `:sql` for a set of (potentially database-dependent) SQL statements. -* `config.active_record.error_on_ignored_order_or_limit` specifies if an error should be raised if the order or limit of a query is ignored during a batch query. The options are true (raise error) or false (warn). Default is false. +* `config.active_record.error_on_ignored_order` specifies if an error should be raised if the order of a query is ignored during a batch query. The options are `true` (raise error) or `false` (warn). Default is `false`. -* `config.active_record.timestamped_migrations` controls whether migrations are numbered with serial integers or with timestamps. The default is true, to use timestamps, which are preferred if there are multiple developers working on the same application. +* `config.active_record.timestamped_migrations` controls whether migrations are numbered with serial integers or with timestamps. The default is `true`, to use timestamps, which are preferred if there are multiple developers working on the same application. -* `config.active_record.lock_optimistically` controls whether Active Record will use optimistic locking and is true by default. +* `config.active_record.lock_optimistically` controls whether Active Record will use optimistic locking and is `true` by default. * `config.active_record.cache_timestamp_format` controls the format of the timestamp value in the cache key. Default is `:nsec`. @@ -308,17 +350,17 @@ All these configuration options are delegated to the `I18n` library. * `config.active_record.partial_writes` is a boolean value and controls whether or not partial writes are used (i.e. whether updates only set attributes that are dirty). Note that when using partial writes, you should also use optimistic locking `config.active_record.lock_optimistically` since concurrent updates may write attributes based on a possibly stale read state. The default value is `true`. -* `config.active_record.maintain_test_schema` is a boolean value which controls whether Active Record should try to keep your test database schema up-to-date with `db/schema.rb` (or `db/structure.sql`) when you run your tests. The default is true. +* `config.active_record.maintain_test_schema` is a boolean value which controls whether Active Record should try to keep your test database schema up-to-date with `db/schema.rb` (or `db/structure.sql`) when you run your tests. The default is `true`. * `config.active_record.dump_schema_after_migration` is a flag which controls whether or not schema dump should happen (`db/schema.rb` or - `db/structure.sql`) when you run migrations. This is set to false in + `db/structure.sql`) when you run migrations. This is set to `false` in `config/environments/production.rb` which is generated by Rails. The - default value is true if this configuration is not set. + default value is `true` if this configuration is not set. -* `config.active_record.dump_schemas` controls which database schemas will be dumped when calling db:structure:dump. - The options are `:schema_search_path` (the default) which dumps any schemas listed in schema_search_path, - `:all` which always dumps all schemas regardless of the schema_search_path, +* `config.active_record.dump_schemas` controls which database schemas will be dumped when calling `db:structure:dump`. + The options are `:schema_search_path` (the default) which dumps any schemas listed in `schema_search_path`, + `:all` which always dumps all schemas regardless of the `schema_search_path`, or a string of comma separated schemas. * `config.active_record.belongs_to_required_by_default` is a boolean value and @@ -328,19 +370,38 @@ All these configuration options are delegated to the `I18n` library. * `config.active_record.warn_on_records_fetched_greater_than` allows setting a warning threshold for query result size. If the number of records returned by a query exceeds the threshold, a warning is logged. This can be used to - identify queries which might be causing memory bloat. + identify queries which might be causing a memory bloat. * `config.active_record.index_nested_attribute_errors` allows errors for nested - has_many relationships to be displayed with an index as well as the error. - Defaults to false. + `has_many` relationships to be displayed with an index as well as the error. + Defaults to `false`. + +* `config.active_record.use_schema_cache_dump` enables users to get schema cache information + from `db/schema_cache.yml` (generated by `rails db:schema:cache:dump`), instead of + having to send a query to the database to get this information. + Defaults to `true`. The MySQL adapter adds one additional configuration option: -* `ActiveRecord::ConnectionAdapters::Mysql2Adapter.emulate_booleans` controls whether Active Record will consider all `tinyint(1)` columns in a MySQL database to be booleans and is true by default. +* `ActiveRecord::ConnectionAdapters::Mysql2Adapter.emulate_booleans` controls whether Active Record will consider all `tinyint(1)` columns as booleans. Defaults to `true`. + +The PostgreSQL adapter adds one additional configuration option: + +* `ActiveRecord::ConnectionAdapters::PostgreSQLAdapter.create_unlogged_tables` + controls whether database tables created should be "unlogged," which can speed + up performance but adds a risk of data loss if the database crashes. It is + highly recommended that you do not enable this in a production environment. + Defaults to `false` in all environments. -The schema dumper adds one additional configuration option: +The schema dumper adds two additional configuration options: -* `ActiveRecord::SchemaDumper.ignore_tables` accepts an array of tables that should _not_ be included in any generated schema file. This setting is ignored unless `config.active_record.schema_format == :ruby`. +* `ActiveRecord::SchemaDumper.ignore_tables` accepts an array of tables that should _not_ be included in any generated schema file. + +* `ActiveRecord::SchemaDumper.fk_ignore_pattern` allows setting a different regular + expression that will be used to decide whether a foreign key's name should be + dumped to db/schema.rb or not. By default, foreign key names starting with + `fk_rails_` are not exported to the database schema dump. + Defaults to `/^fk_rails_[0-9a-f]{10}$/`. ### Configuring Action Controller @@ -348,11 +409,11 @@ The schema dumper adds one additional configuration option: * `config.action_controller.asset_host` sets the host for the assets. Useful when CDNs are used for hosting assets rather than the application server itself. -* `config.action_controller.perform_caching` configures whether the application should perform the caching features provided by the Action Controller component or not. Set to false in development mode, true in production. +* `config.action_controller.perform_caching` configures whether the application should perform the caching features provided by the Action Controller component or not. Set to `false` in development mode, `true` in production. * `config.action_controller.default_static_extension` configures the extension used for cached pages. Defaults to `.html`. -* `config.action_controller.include_all_helpers` configures whether all view helpers are available everywhere or are scoped to the corresponding controller. If set to `false`, `UsersHelper` methods are only available for views rendered as part of `UsersController`. If `true`, `UsersHelper` methods are available everywhere. The default is `true`. +* `config.action_controller.include_all_helpers` configures whether all view helpers are available everywhere or are scoped to the corresponding controller. If set to `false`, `UsersHelper` methods are only available for views rendered as part of `UsersController`. If `true`, `UsersHelper` methods are available everywhere. The default configuration behavior (when this option is not explicitly set to `true` or `false`) is that all view helpers are available to each controller. * `config.action_controller.logger` accepts a logger conforming to the interface of Log4r or the default Ruby Logger class, which is then used to log information from Action Controller. Set to `nil` to disable logging. @@ -364,13 +425,31 @@ The schema dumper adds one additional configuration option: * `config.action_controller.per_form_csrf_tokens` configures whether CSRF tokens are only valid for the method/action they were generated for. +* `config.action_controller.default_protect_from_forgery` determines whether forgery protection is added on `ActionController:Base`. This is false by default. + * `config.action_controller.relative_url_root` can be used to tell Rails that you are [deploying to a subdirectory](configuring.html#deploy-to-a-subdirectory-relative-url-root). The default is `ENV['RAILS_RELATIVE_URL_ROOT']`. * `config.action_controller.permit_all_parameters` sets all the parameters for mass assignment to be permitted by default. The default value is `false`. * `config.action_controller.action_on_unpermitted_parameters` enables logging or raising an exception if parameters that are not explicitly permitted are found. Set to `:log` or `:raise` to enable. The default value is `:log` in development and test environments, and `false` in all other environments. -* `config.action_controller.always_permitted_parameters` sets a list of whitelisted parameters that are permitted by default. The default values are `['controller', 'action']`. +* `config.action_controller.always_permitted_parameters` sets a list of permitted parameters that are permitted by default. The default values are `['controller', 'action']`. + +* `config.action_controller.enable_fragment_cache_logging` determines whether to log fragment cache reads and writes in verbose format as follows: + + ``` + Read fragment views/v1/2914079/v1/2914079/recordings/70182313-20160225015037000000/d0bdf2974e1ef6d31685c3b392ad0b74 (0.6ms) + Rendered messages/_message.html.erb in 1.2 ms [cache hit] + Write fragment views/v1/2914079/v1/2914079/recordings/70182313-20160225015037000000/3b4e249ac9d168c617e32e84b99218b5 (1.1ms) + Rendered recordings/threads/_thread.html.erb in 1.5 ms [cache miss] + ``` + + By default it is set to `false` which results in following output: + + ``` + Rendered messages/_message.html.erb in 1.2 ms [cache hit] + Rendered recordings/threads/_thread.html.erb in 1.5 ms [cache miss] + ``` ### Configuring Action Dispatch @@ -382,7 +461,10 @@ The schema dumper adds one additional configuration option: config.action_dispatch.default_headers = { 'X-Frame-Options' => 'SAMEORIGIN', 'X-XSS-Protection' => '1; mode=block', - 'X-Content-Type-Options' => 'nosniff' + 'X-Content-Type-Options' => 'nosniff', + 'X-Download-Options' => 'noopen', + 'X-Permitted-Cross-Domain-Policies' => 'none', + 'Referrer-Policy' => 'strict-origin-when-cross-origin' } ``` @@ -390,6 +472,10 @@ The schema dumper adds one additional configuration option: * `config.action_dispatch.tld_length` sets the TLD (top-level domain) length for the application. Defaults to `1`. +* `config.action_dispatch.ignore_accept_header` is used to determine whether to ignore accept headers from a request. Defaults to `false`. + +* `config.action_dispatch.x_sendfile_header` specifies server specific X-Sendfile header. This is useful for accelerated file sending from server. For example it can be set to 'X-Sendfile' for Apache. + * `config.action_dispatch.http_auth_salt` sets the HTTP Auth salt value. Defaults to `'http authentication'`. @@ -397,34 +483,56 @@ to `'http authentication'`. Defaults to `'signed cookie'`. * `config.action_dispatch.encrypted_cookie_salt` sets the encrypted cookies salt -value. Defaults to `'encrypted cookie'`. + value. Defaults to `'encrypted cookie'`. * `config.action_dispatch.encrypted_signed_cookie_salt` sets the signed -encrypted cookies salt value. Defaults to `'signed encrypted cookie'`. + encrypted cookies salt value. Defaults to `'signed encrypted cookie'`. + +* `config.action_dispatch.authenticated_encrypted_cookie_salt` sets the + authenticated encrypted cookie salt. Defaults to `'authenticated encrypted + cookie'`. + +* `config.action_dispatch.encrypted_cookie_cipher` sets the cipher to be + used for encrypted cookies. This defaults to `"aes-256-gcm"`. + +* `config.action_dispatch.signed_cookie_digest` sets the digest to be + used for signed cookies. This defaults to `"SHA1"`. + +* `config.action_dispatch.cookies_rotations` allows rotating + secrets, ciphers, and digests for encrypted and signed cookies. + +* `config.action_dispatch.use_authenticated_cookie_encryption` controls whether + signed and encrypted cookies use the AES-256-GCM cipher or + the older AES-256-CBC cipher. It defaults to `true`. + +* `config.action_dispatch.use_cookies_with_metadata` enables writing + cookies with the purpose and expiry metadata embedded. It defaults to `true`. * `config.action_dispatch.perform_deep_munge` configures whether `deep_munge` method should be performed on the parameters. See [Security Guide](security.html#unsafe-query-generation) - for more information. It defaults to true. + for more information. It defaults to `true`. * `config.action_dispatch.rescue_responses` configures what exceptions are assigned to an HTTP status. It accepts a hash and you can specify pairs of exception/status. By default, this is defined as: ```ruby config.action_dispatch.rescue_responses = { - 'ActionController::RoutingError' => :not_found, - 'AbstractController::ActionNotFound' => :not_found, - 'ActionController::MethodNotAllowed' => :method_not_allowed, - 'ActionController::UnknownHttpMethod' => :method_not_allowed, - 'ActionController::NotImplemented' => :not_implemented, - 'ActionController::UnknownFormat' => :not_acceptable, - 'ActionController::InvalidAuthenticityToken' => :unprocessable_entity, - 'ActionController::InvalidCrossOriginRequest' => :unprocessable_entity, - 'ActionDispatch::ParamsParser::ParseError' => :bad_request, - 'ActionController::BadRequest' => :bad_request, - 'ActionController::ParameterMissing' => :bad_request, - 'ActiveRecord::RecordNotFound' => :not_found, - 'ActiveRecord::StaleObjectError' => :conflict, - 'ActiveRecord::RecordInvalid' => :unprocessable_entity, - 'ActiveRecord::RecordNotSaved' => :unprocessable_entity + 'ActionController::RoutingError' => :not_found, + 'AbstractController::ActionNotFound' => :not_found, + 'ActionController::MethodNotAllowed' => :method_not_allowed, + 'ActionController::UnknownHttpMethod' => :method_not_allowed, + 'ActionController::NotImplemented' => :not_implemented, + 'ActionController::UnknownFormat' => :not_acceptable, + 'ActionController::InvalidAuthenticityToken' => :unprocessable_entity, + 'ActionController::InvalidCrossOriginRequest' => :unprocessable_entity, + 'ActionDispatch::Http::Parameters::ParseError' => :bad_request, + 'ActionController::BadRequest' => :bad_request, + 'ActionController::ParameterMissing' => :bad_request, + 'Rack::QueryParser::ParameterTypeError' => :bad_request, + 'Rack::QueryParser::InvalidParameterError' => :bad_request, + 'ActiveRecord::RecordNotFound' => :not_found, + 'ActiveRecord::StaleObjectError' => :conflict, + 'ActiveRecord::RecordInvalid' => :unprocessable_entity, + 'ActiveRecord::RecordNotSaved' => :unprocessable_entity } ``` @@ -432,14 +540,14 @@ encrypted cookies salt value. Defaults to `'signed encrypted cookie'`. * `ActionDispatch::Callbacks.before` takes a block of code to run before the request. -* `ActionDispatch::Callbacks.to_prepare` takes a block to run after `ActionDispatch::Callbacks.before`, but before the request. Runs for every request in `development` mode, but only once for `production` or environments with `cache_classes` set to `true`. - * `ActionDispatch::Callbacks.after` takes a block of code to run after the request. ### Configuring Action View `config.action_view` includes a small number of configuration settings: +* `config.action_view.cache_template_loading` controls whether or not templates should be reloaded on each request. Defaults to whatever is set for `config.cache_classes`. + * `config.action_view.field_error_proc` provides an HTML generator for displaying errors that come from Active Model. The default is ```ruby @@ -459,7 +567,7 @@ encrypted cookies salt value. Defaults to `'signed encrypted cookie'`. * `config.action_view.embed_authenticity_token_in_remote_forms` allows you to set the default behavior for `authenticity_token` in forms with `remote: - true`. By default it's set to false, which means that remote forms will not + true`. By default it's set to `false`, which means that remote forms will not include `authenticity_token`, which is helpful when you're fragment-caching the form. Remote forms get the authenticity from the `meta` tag, so embedding is unnecessary unless you support browsers without JavaScript. In such case @@ -475,12 +583,41 @@ encrypted cookies salt value. Defaults to `'signed encrypted cookie'`. The default setting is `true`, which uses the partial at `/admin/articles/_article.erb`. Setting the value to `false` would render `/articles/_article.erb`, which is the same behavior as rendering from a non-namespaced controller such as `ArticlesController`. * `config.action_view.raise_on_missing_translations` determines whether an - error should be raised for missing translations. + error should be raised for missing translations. This defaults to `false`. * `config.action_view.automatically_disable_submit_tag` determines whether - submit_tag should automatically disable on click, this defaults to true. + `submit_tag` should automatically disable on click, this defaults to `true`. + +* `config.action_view.debug_missing_translation` determines whether to wrap the missing translations key in a `<span>` tag or not. This defaults to `true`. + +* `config.action_view.form_with_generates_remote_forms` determines whether `form_with` generates remote forms or not. This defaults to `true`. + +* `config.action_view.form_with_generates_ids` determines whether `form_with` generates ids on inputs. This defaults to `true`. + +* `config.action_view.default_enforce_utf8` determines whether forms are generated with a hidden tag that forces older versions of Internet Explorer to submit forms encoded in UTF-8. This defaults to `false`. + + +### Configuring Action Mailbox + +`config.action_mailbox` provides the following configuration options: + +* `config.action_mailbox.logger` contains the logger used by Action Mailbox. It accepts a logger conforming to the interface of Log4r or the default Ruby Logger class. The default is `Rails.logger`. + + ```ruby + config.action_mailbox.logger = ActiveSupport::Logger.new(STDOUT) + ``` + +* `config.action_mailbox.incinerate_after` accepts an `ActiveSupport::Duration` indicating how long after processing `ActionMailbox::InboundEmail` records should be destroyed. It defaults to `30.days`. + + ```ruby + # Incinerate inbound emails 14 days after processing. + config.action_mailbox.incinerate_after = 14.days + ``` + +* `config.action_mailbox.queues.incineration` accepts a symbol indicating the Active Job queue to use for incineration jobs. It defaults to `:action_mailbox_incineration`. + +* `config.action_mailbox.queues.routing` accepts a symbol indicating the Active Job queue to use for routing jobs. It defaults to `:action_mailbox_routing`. -* `config.action_view.debug_missing_translation` determins whether to wrap the missing translations key in a `<span>` tag or not. This defaults to true. ### Configuring Action Mailer @@ -495,16 +632,19 @@ There are a number of settings available on `config.action_mailer`: * `:user_name` - If your mail server requires authentication, set the username in this setting. * `:password` - If your mail server requires authentication, set the password in this setting. * `:authentication` - If your mail server requires authentication, you need to specify the authentication type here. This is a symbol and one of `:plain`, `:login`, `:cram_md5`. + * `:enable_starttls_auto` - Detects if STARTTLS is enabled in your SMTP server and starts to use it. It defaults to `true`. + * `:openssl_verify_mode` - When using TLS, you can set how OpenSSL checks the certificate. This is useful if you need to validate a self-signed and/or a wildcard certificate. This can be one of the OpenSSL verify constants, `:none` or `:peer` -- or the constant directly `OpenSSL::SSL::VERIFY_NONE` or `OpenSSL::SSL::VERIFY_PEER`, respectively. + * `:ssl/:tls` - Enables the SMTP connection to use SMTP/TLS (SMTPS: SMTP over direct TLS connection). * `config.action_mailer.sendmail_settings` allows detailed configuration for the `sendmail` delivery method. It accepts a hash of options, which can include any of these options: * `:location` - The location of the sendmail executable. Defaults to `/usr/sbin/sendmail`. - * `:arguments` - The command line arguments. Defaults to `-i -t`. + * `:arguments` - The command line arguments. Defaults to `-i`. -* `config.action_mailer.raise_delivery_errors` specifies whether to raise an error if email delivery cannot be completed. It defaults to true. +* `config.action_mailer.raise_delivery_errors` specifies whether to raise an error if email delivery cannot be completed. It defaults to `true`. * `config.action_mailer.delivery_method` defines the delivery method and defaults to `:smtp`. See the [configuration section in the Action Mailer guide](action_mailer_basics.html#action-mailer-configuration) for more info. -* `config.action_mailer.perform_deliveries` specifies whether mail will actually be delivered and is true by default. It can be convenient to set it to false for testing. +* `config.action_mailer.perform_deliveries` specifies whether mail will actually be delivered and is true by default. It can be convenient to set it to `false` for testing. * `config.action_mailer.default_options` configures Action Mailer defaults. Use to set options like `from` or `reply_to` for every mailer. These default to: @@ -535,6 +675,12 @@ There are a number of settings available on `config.action_mailer`: config.action_mailer.interceptors = ["MailInterceptor"] ``` +* `config.action_mailer.preview_interceptors` registers interceptors which will be called before mail is previewed. + + ```ruby + config.action_mailer.preview_interceptors = ["MyPreviewMailInterceptor"] + ``` + * `config.action_mailer.preview_path` specifies the location of mailer previews. ```ruby @@ -550,7 +696,9 @@ There are a number of settings available on `config.action_mailer`: * `config.action_mailer.deliver_later_queue_name` specifies the queue name for mailers. By default this is `mailers`. -* `config.action_mailer.perform_caching` specifies whether the mailer templates should perform fragment caching or not. By default this is false in all environments. +* `config.action_mailer.perform_caching` specifies whether the mailer templates should perform fragment caching or not. By default this is `false` in all environments. + +* `config.action_mailer.delivery_job` specifies delivery job for mail. Defaults to `ActionMailer::DeliveryJob`. ### Configuring Active Support @@ -559,7 +707,7 @@ There are a few configuration options available in Active Support: * `config.active_support.bare` enables or disables the loading of `active_support/all` when booting Rails. Defaults to `nil`, which means `active_support/all` is loaded. -* `config.active_support.test_order` sets the order that test cases are executed. Possible values are `:random` and `:sorted`. This option is set to `:random` in `config/environments/test.rb` in newly-generated applications. If you have an application that does not specify a `test_order`, it will default to `:sorted`, *until* Rails 5.0, when the default will become `:random`. +* `config.active_support.test_order` sets the order in which the test cases are executed. Possible values are `:random` and `:sorted`. Defaults to `:random`. * `config.active_support.escape_html_entities_in_json` enables or disables the escaping of HTML entities in JSON serialization. Defaults to `true`. @@ -567,7 +715,9 @@ There are a few configuration options available in Active Support: * `config.active_support.time_precision` sets the precision of JSON encoded time values. Defaults to `3`. -* `ActiveSupport.halt_callback_chains_on_return_false` specifies whether Active Record and Active Model callback chains can be halted by returning `false` in a 'before' callback. When set to `false`, callback chains are halted only when explicitly done so with `throw(:abort)`. When set to `true`, callback chains are halted when a callback returns false (the previous behavior before Rails 5) and a deprecation warning is given. Defaults to `true` during the deprecation period. New Rails 5 apps generate an initializer file called `callback_terminator.rb` which sets the value to `false`. This file is *not* added when running `rails app:update`, so returning `false` will still work on older apps ported to Rails 5 and display a deprecation warning to prompt users to update their code. +* `config.active_support.use_sha1_digests` specifies whether to use SHA-1 instead of MD5 to generate non-sensitive digests, such as the ETag header. Defaults to false. + +* `config.active_support.use_authenticated_message_encryption` specifies whether to use AES-256-GCM authenticated encryption as the default cipher for encrypting messages instead of AES-256-CBC. This is false by default. * `ActiveSupport::Logger.silencer` is set to `false` to disable the ability to silence logging in a block. The default is `true`. @@ -577,13 +727,13 @@ There are a few configuration options available in Active Support: * `ActiveSupport::Deprecation.silence` takes a block in which all deprecation warnings are silenced. -* `ActiveSupport::Deprecation.silenced` sets whether or not to display deprecation warnings. +* `ActiveSupport::Deprecation.silenced` sets whether or not to display deprecation warnings. The default is `false`. ### Configuring Active Job `config.active_job` provides the following configuration options: -* `config.active_job.queue_adapter` sets the adapter for the queueing backend. The default adapter is `:async`. For an up-to-date list of built-in adapters see the [ActiveJob::QueueAdapters API documentation](http://api.rubyonrails.org/classes/ActiveJob/QueueAdapters.html). +* `config.active_job.queue_adapter` sets the adapter for the queuing backend. The default adapter is `:async`. For an up-to-date list of built-in adapters see the [ActiveJob::QueueAdapters API documentation](https://api.rubyonrails.org/classes/ActiveJob/QueueAdapters.html). ```ruby # Be sure to have the adapter's gem in your Gemfile @@ -632,6 +782,10 @@ There are a few configuration options available in Active Support: * `config.active_job.logger` accepts a logger conforming to the interface of Log4r or the default Ruby Logger class, which is then used to log information from Active Job. You can retrieve this logger by calling `logger` on either an Active Job class or an Active Job instance. Set to `nil` to disable logging. +* `config.active_job.custom_serializers` allows to set custom argument serializers. Defaults to `[]`. + +* `config.active_job.return_false_on_aborted_enqueue` change the return value of `#enqueue` to false instead of the job instance when the enqueuing is aborted. Defaults to `false`. + ### Configuring Action Cable * `config.action_cable.url` accepts a string for the URL for where @@ -643,6 +797,100 @@ main application. You can set this as nil to not mount Action Cable as part of your normal Rails server. +You can find more detailed configuration options in the +[Action Cable Overview](action_cable_overview.html#configuration). + + +### Configuring Active Storage + +`config.active_storage` provides the following configuration options: + +* `config.active_storage.variant_processor` accepts a symbol `:mini_magick` or `:vips`, specifying whether variant transformations will be performed with MiniMagick or ruby-vips. The default is `:mini_magick`. + +* `config.active_storage.analyzers` accepts an array of classes indicating the analyzers available for Active Storage blobs. The default is `[ActiveStorage::Analyzer::ImageAnalyzer, ActiveStorage::Analyzer::VideoAnalyzer]`. The former can extract width and height of an image blob; the latter can extract width, height, duration, angle, and aspect ratio of a video blob. + +* `config.active_storage.previewers` accepts an array of classes indicating the image previewers available in Active Storage blobs. The default is `[ActiveStorage::Previewer::PDFPreviewer, ActiveStorage::Previewer::VideoPreviewer]`. The former can generate a thumbnail from the first page of a PDF blob; the latter from the relevant frame of a video blob. + +* `config.active_storage.paths` accepts a hash of options indicating the locations of previewer/analyzer commands. The default is `{}`, meaning the commands will be looked for in the default path. Can include any of these options: + * `:ffprobe` - The location of the ffprobe executable. + * `:mutool` - The location of the mutool executable. + * `:ffmpeg` - The location of the ffmpeg executable. + + ```ruby + config.active_storage.paths[:ffprobe] = '/usr/local/bin/ffprobe' + ``` + +* `config.active_storage.variable_content_types` accepts an array of strings indicating the content types that Active Storage can transform through ImageMagick. The default is `%w(image/png image/gif image/jpg image/jpeg image/pjpeg image/tiff image/vnd.adobe.photoshop image/vnd.microsoft.icon)`. + +* `config.active_storage.content_types_to_serve_as_binary` accepts an array of strings indicating the content types that Active Storage will always serve as an attachment, rather than inline. The default is `%w(text/html +text/javascript image/svg+xml application/postscript application/x-shockwave-flash text/xml application/xml application/xhtml+xml)`. + +* `config.active_storage.queues.analysis` accepts a symbol indicating the Active Job queue to use for analysis jobs. When this option is `nil`, analysis jobs are sent to the default Active Job queue (see `config.active_job.default_queue_name`). + + ```ruby + config.active_storage.queues.analysis = :low_priority + ``` + +* `config.active_storage.queues.purge` accepts a symbol indicating the Active Job queue to use for purge jobs. When this option is `nil`, purge jobs are sent to the default Active Job queue (see `config.active_job.default_queue_name`). + + ```ruby + config.active_storage.queues.purge = :low_priority + ``` + +* `config.active_storage.logger` can be used to set the logger used by Active Storage. Accepts a logger conforming to the interface of Log4r or the default Ruby Logger class. + + ```ruby + config.active_storage.logger = ActiveSupport::Logger.new(STDOUT) + ``` + +* `config.active_storage.service_urls_expire_in` determines the default expiry of URLs generated by: + * `ActiveStorage::Blob#service_url` + * `ActiveStorage::Blob#service_url_for_direct_upload` + * `ActiveStorage::Variant#service_url` + + The default is 5 minutes. + +* `config.active_storage.routes_prefix` can be used to set the route prefix for the routes served by Active Storage. Accepts a string that will be prepended to the generated routes. + + ```ruby + config.active_storage.routes_prefix = '/files' + ``` + + The default is `/rails/active_storage` + +### Results of `load_defaults` + +#### With '5.0': + +- `config.action_controller.per_form_csrf_tokens`: `true` +- `config.action_controller.forgery_protection_origin_check`: `true` +- `ActiveSupport.to_time_preserves_timezone`: `true` +- `config.active_record.belongs_to_required_by_default`: `true` +- `config.ssl_options`: `{ hsts: { subdomains: true } }` + +#### With '5.1': + +- `config.assets.unknown_asset_fallback`: `false` +- `config.action_view.form_with_generates_remote_forms`: `true` + +#### With '5.2': + +- `config.active_record.cache_versioning`: `true` +- `action_dispatch.use_authenticated_cookie_encryption`: `true` +- `config.active_support.use_authenticated_message_encryption`: `true` +- `config.active_support.use_sha1_digests`: `true` +- `config.action_controller.default_protect_from_forgery`: `true` +- `config.action_view.form_with_generates_ids`: `true` + +#### With '6.0': + +- `config.action_view.default_enforce_utf8`: `false` +- `config.action_dispatch.use_cookies_with_metadata`: `true` +- `config.action_mailer.delivery_job`: `"ActionMailer::MailDeliveryJob"` +- `config.active_job.return_false_on_aborted_enqueue`: `true` +- `config.active_storage.queues.analysis`: `:active_storage_analysis` +- `config.active_storage.queues.purge`: `:active_storage_purge` + ### Configuring a Database Just about every Rails application will interact with a database. You can connect to the database by setting an environment variable `ENV['DATABASE_URL']` or by using a configuration file called `config/database.yml`. @@ -721,8 +969,16 @@ development: $ echo $DATABASE_URL postgresql://localhost/my_database -$ bin/rails runner 'puts ActiveRecord::Base.configurations' -{"development"=>{"adapter"=>"postgresql", "host"=>"localhost", "database"=>"my_database"}} +$ rails runner 'puts ActiveRecord::Base.configurations' +#<ActiveRecord::DatabaseConfigurations:0x00007fd50e209a28> + +$ rails runner 'puts ActiveRecord::Base.configurations.inspect' +#<ActiveRecord::DatabaseConfigurations:0x00007fc8eab02880 @configurations=[ + #<ActiveRecord::DatabaseConfigurations::UrlConfig:0x00007fc8eab020b0 + @env_name="development", @spec_name="primary", + @config={"adapter"=>"postgresql", "database"=>"my_database", "host"=>"localhost"} + @url="postgresql://localhost/my_database"> + ] ``` Here the adapter, host, and database match the information in `ENV['DATABASE_URL']`. @@ -738,8 +994,16 @@ development: $ echo $DATABASE_URL postgresql://localhost/my_database -$ bin/rails runner 'puts ActiveRecord::Base.configurations' -{"development"=>{"adapter"=>"postgresql", "host"=>"localhost", "database"=>"my_database", "pool"=>5}} +$ rails runner 'puts ActiveRecord::Base.configurations' +#<ActiveRecord::DatabaseConfigurations:0x00007fd50e209a28> + +$ rails runner 'puts ActiveRecord::Base.configurations.inspect' +#<ActiveRecord::DatabaseConfigurations:0x00007fc8eab02880 @configurations=[ + #<ActiveRecord::DatabaseConfigurations::UrlConfig:0x00007fc8eab020b0 + @env_name="development", @spec_name="primary", + @config={"adapter"=>"postgresql", "database"=>"my_database", "host"=>"localhost", "pool"=>5} + @url="postgresql://localhost/my_database"> + ] ``` Since pool is not in the `ENV['DATABASE_URL']` provided connection information its information is merged in. Since `adapter` is duplicate, the `ENV['DATABASE_URL']` connection information wins. @@ -754,8 +1018,16 @@ development: $ echo $DATABASE_URL postgresql://localhost/my_database -$ bin/rails runner 'puts ActiveRecord::Base.configurations' -{"development"=>{"adapter"=>"sqlite3", "database"=>"NOT_my_database"}} +$ rails runner 'puts ActiveRecord::Base.configurations' +#<ActiveRecord::DatabaseConfigurations:0x00007fd50e209a28> + +$ rails runner 'puts ActiveRecord::Base.configurations.inspect' +#<ActiveRecord::DatabaseConfigurations:0x00007fc8eab02880 @configurations=[ + #<ActiveRecord::DatabaseConfigurations::UrlConfig:0x00007fc8eab020b0 + @env_name="development", @spec_name="primary", + @config={"adapter"=>"sqlite3", "database"=>"NOT_my_database"} + @url="sqlite3:NOT_my_database"> + ] ``` Here the connection information in `ENV['DATABASE_URL']` is ignored, note the different adapter and database name. @@ -784,16 +1056,16 @@ development: timeout: 5000 ``` -NOTE: Rails uses an SQLite3 database for data storage by default because it is a zero configuration database that just works. Rails also supports MySQL and PostgreSQL "out of the box", and has plugins for many database systems. If you are using a database in a production environment Rails most likely has an adapter for it. +NOTE: Rails uses an SQLite3 database for data storage by default because it is a zero configuration database that just works. Rails also supports MySQL (including MariaDB) and PostgreSQL "out of the box", and has plugins for many database systems. If you are using a database in a production environment Rails most likely has an adapter for it. -#### Configuring a MySQL Database +#### Configuring a MySQL or MariaDB Database -If you choose to use MySQL instead of the shipped SQLite3 database, your `config/database.yml` will look a little different. Here's the development section: +If you choose to use MySQL or MariaDB instead of the shipped SQLite3 database, your `config/database.yml` will look a little different. Here's the development section: ```yaml development: adapter: mysql2 - encoding: utf8 + encoding: utf8mb4 database: blog_development pool: 5 username: root @@ -801,7 +1073,17 @@ development: socket: /tmp/mysql.sock ``` -If your development computer's MySQL installation includes a root user with an empty password, this configuration should work for you. Otherwise, change the username and password in the `development` section as appropriate. +If your development database has a root user with an empty password, this configuration should work for you. Otherwise, change the username and password in the `development` section as appropriate. + +NOTE: If your MySQL version is 5.5 or 5.6 and want to use the `utf8mb4` character set by default, please configure your MySQL server to support the longer key prefix by enabling `innodb_large_prefix` system variable. + +Advisory Locks are enabled by default on MySQL and are used to make database migrations concurrent safe. You can disable advisory locks by setting `advisory_locks` to `false`: + +```yaml +production: + adapter: mysql2 + advisory_locks: false +``` #### Configuring a PostgreSQL Database @@ -815,12 +1097,13 @@ development: pool: 5 ``` -Prepared Statements are enabled by default on PostgreSQL. You can disable prepared statements by setting `prepared_statements` to `false`: +By default Active Record uses database features like prepared statements and advisory locks. You might need to disable those features if you're using an external connection pooler like PgBouncer: ```yaml production: adapter: postgresql prepared_statements: false + advisory_locks: false ``` If enabled, Active Record will create up to `1000` prepared statements per database connection by default. To modify this behavior you can set `statement_limit` to a different value: @@ -843,9 +1126,9 @@ development: database: db/development.sqlite3 ``` -#### Configuring a MySQL Database for JRuby Platform +#### Configuring a MySQL or MariaDB Database for JRuby Platform -If you choose to use MySQL and are using JRuby, your `config/database.yml` will look a little different. Here's the development section: +If you choose to use MySQL or MariaDB and are using JRuby, your `config/database.yml` will look a little different. Here's the development section: ```yaml development: @@ -876,10 +1159,10 @@ By default Rails ships with three environments: "development", "test", and "prod Imagine you have a server which mirrors the production environment but is only used for testing. Such a server is commonly called a "staging server". To define an environment called "staging" for this server, just create a file called `config/environments/staging.rb`. Please use the contents of any existing file in `config/environments` as a starting point and make the necessary changes from there. -That environment is no different than the default ones, start a server with `rails server -e staging`, a console with `rails console staging`, `Rails.env.staging?` works, etc. +That environment is no different than the default ones, start a server with `rails server -e staging`, a console with `rails console -e staging`, `Rails.env.staging?` works, etc. -### Deploy to a subdirectory (relative url root) +### Deploy to a subdirectory (relative URL root) By default Rails expects that your application is running at the root (eg. `/`). This section explains how to run your application inside a directory. @@ -898,7 +1181,7 @@ Rails will now prepend "/app1" when generating links. #### Using Passenger -Passenger makes it easy to run your application in a subdirectory. You can find the relevant configuration in the [Passenger manual](http://www.modrails.com/documentation/Users%20guide%20Apache.html#deploying_rails_to_sub_uri). +Passenger makes it easy to run your application in a subdirectory. You can find the relevant configuration in the [Passenger manual](https://www.phusionpassenger.com/library/deploy/apache/deploy/ruby/#deploying-an-app-to-a-sub-uri-or-subdirectory). #### Using a Reverse Proxy @@ -906,17 +1189,17 @@ Deploying your application using a reverse proxy has definite advantages over tr Many modern web servers can be used as a proxy server to balance third-party elements such as caching servers or application servers. -One such application server you can use is [Unicorn](http://unicorn.bogomips.org/) to run behind a reverse proxy. +One such application server you can use is [Unicorn](https://bogomips.org/unicorn/) to run behind a reverse proxy. In this case, you would need to configure the proxy server (NGINX, Apache, etc) to accept connections from your application server (Unicorn). By default Unicorn will listen for TCP connections on port 8080, but you can change the port or configure it to use sockets instead. -You can find more information in the [Unicorn readme](http://unicorn.bogomips.org/README.html) and understand the [philosophy](http://unicorn.bogomips.org/PHILOSOPHY.html) behind it. +You can find more information in the [Unicorn readme](https://bogomips.org/unicorn/README.html) and understand the [philosophy](https://bogomips.org/unicorn/PHILOSOPHY.html) behind it. Once you've configured the application server, you must proxy requests to it by configuring your web server appropriately. For example your NGINX config may include: ``` upstream application_server { - server 0.0.0.0:8080 + server 0.0.0.0:8080; } server { @@ -938,7 +1221,7 @@ server { } ``` -Be sure to read the [NGINX documentation](http://nginx.org/en/docs/) for the most up-to-date information. +Be sure to read the [NGINX documentation](https://nginx.org/en/docs/) for the most up-to-date information. Rails Environment Settings @@ -958,9 +1241,11 @@ Using Initializer Files After loading the framework and any gems in your application, Rails turns to loading initializers. An initializer is any Ruby file stored under `config/initializers` in your application. You can use initializers to hold configuration settings that should be made after all of the frameworks and gems are loaded, such as options to configure settings for these parts. +NOTE: There is no guarantee that your initializers will run after all the gem initializers, so any initialization code that depends on a given gem having been initialized should go into a `config.after_initialize` block. + NOTE: You can use subfolders to organize your initializers if you like, because Rails will look into the whole file hierarchy from the initializers folder on down. -TIP: If you have any ordering dependency in your initializers, you can control the load order through naming. Initializer files are loaded in alphabetical order by their path. For example, `01_critical.rb` will be loaded before `02_normal.rb`. +TIP: While Rails supports numbering of initializer file names for load ordering purposes, a better technique is to place any code that need to load in a specific order within the same file. This reduces file name churn, makes dependencies more explicit, and can help surface new concepts within your application. Initialization events --------------------- @@ -1023,110 +1308,110 @@ Because `Rails::Application` inherits from `Rails::Railtie` (indirectly), you ca Below is a comprehensive list of all the initializers found in Rails in the order that they are defined (and therefore run in, unless otherwise stated). -* `load_environment_hook` Serves as a placeholder so that `:load_environment_config` can be defined to run before it. +* `load_environment_hook`: Serves as a placeholder so that `:load_environment_config` can be defined to run before it. -* `load_active_support` Requires `active_support/dependencies` which sets up the basis for Active Support. Optionally requires `active_support/all` if `config.active_support.bare` is un-truthful, which is the default. +* `load_active_support`: Requires `active_support/dependencies` which sets up the basis for Active Support. Optionally requires `active_support/all` if `config.active_support.bare` is un-truthful, which is the default. -* `initialize_logger` Initializes the logger (an `ActiveSupport::Logger` object) for the application and makes it accessible at `Rails.logger`, provided that no initializer inserted before this point has defined `Rails.logger`. +* `initialize_logger`: Initializes the logger (an `ActiveSupport::Logger` object) for the application and makes it accessible at `Rails.logger`, provided that no initializer inserted before this point has defined `Rails.logger`. -* `initialize_cache` If `Rails.cache` isn't set yet, initializes the cache by referencing the value in `config.cache_store` and stores the outcome as `Rails.cache`. If this object responds to the `middleware` method, its middleware is inserted before `Rack::Runtime` in the middleware stack. +* `initialize_cache`: If `Rails.cache` isn't set yet, initializes the cache by referencing the value in `config.cache_store` and stores the outcome as `Rails.cache`. If this object responds to the `middleware` method, its middleware is inserted before `Rack::Runtime` in the middleware stack. -* `set_clear_dependencies_hook` This initializer - which runs only if `cache_classes` is set to `false` - uses `ActionDispatch::Callbacks.after` to remove the constants which have been referenced during the request from the object space so that they will be reloaded during the following request. +* `set_clear_dependencies_hook`: This initializer - which runs only if `cache_classes` is set to `false` - uses `ActionDispatch::Callbacks.after` to remove the constants which have been referenced during the request from the object space so that they will be reloaded during the following request. -* `initialize_dependency_mechanism` If `config.cache_classes` is true, configures `ActiveSupport::Dependencies.mechanism` to `require` dependencies rather than `load` them. +* `initialize_dependency_mechanism`: If `config.cache_classes` is true, configures `ActiveSupport::Dependencies.mechanism` to `require` dependencies rather than `load` them. -* `bootstrap_hook` Runs all configured `before_initialize` blocks. +* `bootstrap_hook`: Runs all configured `before_initialize` blocks. -* `i18n.callbacks` In the development environment, sets up a `to_prepare` callback which will call `I18n.reload!` if any of the locales have changed since the last request. In production mode this callback will only run on the first request. +* `i18n.callbacks`: In the development environment, sets up a `to_prepare` callback which will call `I18n.reload!` if any of the locales have changed since the last request. In production mode this callback will only run on the first request. -* `active_support.deprecation_behavior` Sets up deprecation reporting for environments, defaulting to `:log` for development, `:notify` for production and `:stderr` for test. If a value isn't set for `config.active_support.deprecation` then this initializer will prompt the user to configure this line in the current environment's `config/environments` file. Can be set to an array of values. +* `active_support.deprecation_behavior`: Sets up deprecation reporting for environments, defaulting to `:log` for development, `:notify` for production, and `:stderr` for test. If a value isn't set for `config.active_support.deprecation` then this initializer will prompt the user to configure this line in the current environment's `config/environments` file. Can be set to an array of values. -* `active_support.initialize_time_zone` Sets the default time zone for the application based on the `config.time_zone` setting, which defaults to "UTC". +* `active_support.initialize_time_zone`: Sets the default time zone for the application based on the `config.time_zone` setting, which defaults to "UTC". -* `active_support.initialize_beginning_of_week` Sets the default beginning of week for the application based on `config.beginning_of_week` setting, which defaults to `:monday`. +* `active_support.initialize_beginning_of_week`: Sets the default beginning of week for the application based on `config.beginning_of_week` setting, which defaults to `:monday`. -* `active_support.set_configs` Sets up Active Support by using the settings in `config.active_support` by `send`'ing the method names as setters to `ActiveSupport` and passing the values through. +* `active_support.set_configs`: Sets up Active Support by using the settings in `config.active_support` by `send`'ing the method names as setters to `ActiveSupport` and passing the values through. -* `action_dispatch.configure` Configures the `ActionDispatch::Http::URL.tld_length` to be set to the value of `config.action_dispatch.tld_length`. +* `action_dispatch.configure`: Configures the `ActionDispatch::Http::URL.tld_length` to be set to the value of `config.action_dispatch.tld_length`. -* `action_view.set_configs` Sets up Action View by using the settings in `config.action_view` by `send`'ing the method names as setters to `ActionView::Base` and passing the values through. +* `action_view.set_configs`: Sets up Action View by using the settings in `config.action_view` by `send`'ing the method names as setters to `ActionView::Base` and passing the values through. -* `action_controller.assets_config` Initializes the `config.actions_controller.assets_dir` to the app's public directory if not explicitly configured +* `action_controller.assets_config`: Initializes the `config.actions_controller.assets_dir` to the app's public directory if not explicitly configured. -* `action_controller.set_helpers_path` Sets Action Controller's helpers_path to the application's helpers_path +* `action_controller.set_helpers_path`: Sets Action Controller's `helpers_path` to the application's `helpers_path`. -* `action_controller.parameters_config` Configures strong parameters options for `ActionController::Parameters` +* `action_controller.parameters_config`: Configures strong parameters options for `ActionController::Parameters`. -* `action_controller.set_configs` Sets up Action Controller by using the settings in `config.action_controller` by `send`'ing the method names as setters to `ActionController::Base` and passing the values through. +* `action_controller.set_configs`: Sets up Action Controller by using the settings in `config.action_controller` by `send`'ing the method names as setters to `ActionController::Base` and passing the values through. -* `action_controller.compile_config_methods` Initializes methods for the config settings specified so that they are quicker to access. +* `action_controller.compile_config_methods`: Initializes methods for the config settings specified so that they are quicker to access. -* `active_record.initialize_timezone` Sets `ActiveRecord::Base.time_zone_aware_attributes` to true, as well as setting `ActiveRecord::Base.default_timezone` to UTC. When attributes are read from the database, they will be converted into the time zone specified by `Time.zone`. +* `active_record.initialize_timezone`: Sets `ActiveRecord::Base.time_zone_aware_attributes` to `true`, as well as setting `ActiveRecord::Base.default_timezone` to UTC. When attributes are read from the database, they will be converted into the time zone specified by `Time.zone`. -* `active_record.logger` Sets `ActiveRecord::Base.logger` - if it's not already set - to `Rails.logger`. +* `active_record.logger`: Sets `ActiveRecord::Base.logger` - if it's not already set - to `Rails.logger`. -* `active_record.migration_error` Configures middleware to check for pending migrations +* `active_record.migration_error`: Configures middleware to check for pending migrations. -* `active_record.check_schema_cache_dump` Loads the schema cache dump if configured and available +* `active_record.check_schema_cache_dump`: Loads the schema cache dump if configured and available. -* `active_record.warn_on_records_fetched_greater_than` Enables warnings when queries return large numbers of records +* `active_record.warn_on_records_fetched_greater_than`: Enables warnings when queries return large numbers of records. -* `active_record.set_configs` Sets up Active Record by using the settings in `config.active_record` by `send`'ing the method names as setters to `ActiveRecord::Base` and passing the values through. +* `active_record.set_configs`: Sets up Active Record by using the settings in `config.active_record` by `send`'ing the method names as setters to `ActiveRecord::Base` and passing the values through. -* `active_record.initialize_database` Loads the database configuration (by default) from `config/database.yml` and establishes a connection for the current environment. +* `active_record.initialize_database`: Loads the database configuration (by default) from `config/database.yml` and establishes a connection for the current environment. -* `active_record.log_runtime` Includes `ActiveRecord::Railties::ControllerRuntime` which is responsible for reporting the time taken by Active Record calls for the request back to the logger. +* `active_record.log_runtime`: Includes `ActiveRecord::Railties::ControllerRuntime` which is responsible for reporting the time taken by Active Record calls for the request back to the logger. -* `active_record.set_reloader_hooks` Resets all reloadable connections to the database if `config.cache_classes` is set to `false`. +* `active_record.set_reloader_hooks`: Resets all reloadable connections to the database if `config.cache_classes` is set to `false`. -* `active_record.add_watchable_files` Adds `schema.rb` and `structure.sql` files to watchable files +* `active_record.add_watchable_files`: Adds `schema.rb` and `structure.sql` files to watchable files. -* `active_job.logger` Sets `ActiveJob::Base.logger` - if it's not already set - +* `active_job.logger`: Sets `ActiveJob::Base.logger` - if it's not already set - to `Rails.logger`. -* `active_job.set_configs` Sets up Active Job by using the settings in `config.active_job` by `send`'ing the method names as setters to `ActiveJob::Base` and passing the values through. +* `active_job.set_configs`: Sets up Active Job by using the settings in `config.active_job` by `send`'ing the method names as setters to `ActiveJob::Base` and passing the values through. -* `action_mailer.logger` Sets `ActionMailer::Base.logger` - if it's not already set - to `Rails.logger`. +* `action_mailer.logger`: Sets `ActionMailer::Base.logger` - if it's not already set - to `Rails.logger`. -* `action_mailer.set_configs` Sets up Action Mailer by using the settings in `config.action_mailer` by `send`'ing the method names as setters to `ActionMailer::Base` and passing the values through. +* `action_mailer.set_configs`: Sets up Action Mailer by using the settings in `config.action_mailer` by `send`'ing the method names as setters to `ActionMailer::Base` and passing the values through. -* `action_mailer.compile_config_methods` Initializes methods for the config settings specified so that they are quicker to access. +* `action_mailer.compile_config_methods`: Initializes methods for the config settings specified so that they are quicker to access. -* `set_load_path` This initializer runs before `bootstrap_hook`. Adds paths specified by `config.load_paths` and all autoload paths to `$LOAD_PATH`. +* `set_load_path`: This initializer runs before `bootstrap_hook`. Adds paths specified by `config.load_paths` and all autoload paths to `$LOAD_PATH`. -* `set_autoload_paths` This initializer runs before `bootstrap_hook`. Adds all sub-directories of `app` and paths specified by `config.autoload_paths`, `config.eager_load_paths` and `config.autoload_once_paths` to `ActiveSupport::Dependencies.autoload_paths`. +* `set_autoload_paths`: This initializer runs before `bootstrap_hook`. Adds all sub-directories of `app` and paths specified by `config.autoload_paths`, `config.eager_load_paths` and `config.autoload_once_paths` to `ActiveSupport::Dependencies.autoload_paths`. -* `add_routing_paths` Loads (by default) all `config/routes.rb` files (in the application and railties, including engines) and sets up the routes for the application. +* `add_routing_paths`: Loads (by default) all `config/routes.rb` files (in the application and railties, including engines) and sets up the routes for the application. -* `add_locales` Adds the files in `config/locales` (from the application, railties and engines) to `I18n.load_path`, making available the translations in these files. +* `add_locales`: Adds the files in `config/locales` (from the application, railties, and engines) to `I18n.load_path`, making available the translations in these files. -* `add_view_paths` Adds the directory `app/views` from the application, railties and engines to the lookup path for view files for the application. +* `add_view_paths`: Adds the directory `app/views` from the application, railties, and engines to the lookup path for view files for the application. -* `load_environment_config` Loads the `config/environments` file for the current environment. +* `load_environment_config`: Loads the `config/environments` file for the current environment. -* `prepend_helpers_path` Adds the directory `app/helpers` from the application, railties and engines to the lookup path for helpers for the application. +* `prepend_helpers_path`: Adds the directory `app/helpers` from the application, railties, and engines to the lookup path for helpers for the application. -* `load_config_initializers` Loads all Ruby files from `config/initializers` in the application, railties and engines. The files in this directory can be used to hold configuration settings that should be made after all of the frameworks are loaded. +* `load_config_initializers`: Loads all Ruby files from `config/initializers` in the application, railties, and engines. The files in this directory can be used to hold configuration settings that should be made after all of the frameworks are loaded. -* `engines_blank_point` Provides a point-in-initialization to hook into if you wish to do anything before engines are loaded. After this point, all railtie and engine initializers are run. +* `engines_blank_point`: Provides a point-in-initialization to hook into if you wish to do anything before engines are loaded. After this point, all railtie and engine initializers are run. -* `add_generator_templates` Finds templates for generators at `lib/templates` for the application, railties and engines and adds these to the `config.generators.templates` setting, which will make the templates available for all generators to reference. +* `add_generator_templates`: Finds templates for generators at `lib/templates` for the application, railties, and engines and adds these to the `config.generators.templates` setting, which will make the templates available for all generators to reference. -* `ensure_autoload_once_paths_as_subset` Ensures that the `config.autoload_once_paths` only contains paths from `config.autoload_paths`. If it contains extra paths, then an exception will be raised. +* `ensure_autoload_once_paths_as_subset`: Ensures that the `config.autoload_once_paths` only contains paths from `config.autoload_paths`. If it contains extra paths, then an exception will be raised. -* `add_to_prepare_blocks` The block for every `config.to_prepare` call in the application, a railtie or engine is added to the `to_prepare` callbacks for Action Dispatch which will be run per request in development, or before the first request in production. +* `add_to_prepare_blocks`: The block for every `config.to_prepare` call in the application, a railtie, or engine is added to the `to_prepare` callbacks for Action Dispatch which will be run per request in development, or before the first request in production. -* `add_builtin_route` If the application is running under the development environment then this will append the route for `rails/info/properties` to the application routes. This route provides the detailed information such as Rails and Ruby version for `public/index.html` in a default Rails application. +* `add_builtin_route`: If the application is running under the development environment then this will append the route for `rails/info/properties` to the application routes. This route provides the detailed information such as Rails and Ruby version for `public/index.html` in a default Rails application. -* `build_middleware_stack` Builds the middleware stack for the application, returning an object which has a `call` method which takes a Rack environment object for the request. +* `build_middleware_stack`: Builds the middleware stack for the application, returning an object which has a `call` method which takes a Rack environment object for the request. -* `eager_load!` If `config.eager_load` is true, runs the `config.before_eager_load` hooks and then calls `eager_load!` which will load all `config.eager_load_namespaces`. +* `eager_load!`: If `config.eager_load` is `true`, runs the `config.before_eager_load` hooks and then calls `eager_load!` which will load all `config.eager_load_namespaces`. -* `finisher_hook` Provides a hook for after the initialization of process of the application is complete, as well as running all the `config.after_initialize` blocks for the application, railties and engines. +* `finisher_hook`: Provides a hook for after the initialization of process of the application is complete, as well as running all the `config.after_initialize` blocks for the application, railties, and engines. -* `set_routes_reloader` Configures Action Dispatch to reload the routes file using `ActionDispatch::Callbacks.to_prepare`. +* `set_routes_reloader_hook`: Configures Action Dispatch to reload the routes file using `ActiveSupport::Callbacks.to_run`. -* `disable_dependency_loading` Disables the automatic dependency loading if the `config.eager_load` is set to true. +* `disable_dependency_loading`: Disables the automatic dependency loading if the `config.eager_load` is set to `true`. Database pooling ---------------- @@ -1141,7 +1426,7 @@ development: timeout: 5000 ``` -Since the connection pooling is handled inside of Active Record by default, all application servers (Thin, mongrel, Unicorn etc.) should behave the same. The database connection pool is initially empty. As demand for connections increases it will create them until it reaches the connection pool limit. +Since the connection pooling is handled inside of Active Record by default, all application servers (Thin, Puma, Unicorn etc.) should behave the same. The database connection pool is initially empty. As demand for connections increases it will create them until it reaches the connection pool limit. Any one request will check out a connection the first time it requires access to the database. At the end of the request it will check the connection back in. This means that the additional connection slot will be available again for the next request in the queue. @@ -1162,21 +1447,25 @@ NOTE. If you are running in a multi-threaded environment, there could be a chanc Custom configuration -------------------- -You can configure your own code through the Rails configuration object with custom configuration. It works like this: +You can configure your own code through the Rails configuration object with +custom configuration under either the `config.x` namespace, or `config` directly. +The key difference between these two is that you should be using `config.x` if you +are defining _nested_ configuration (ex: `config.x.nested.hi`), and just +`config` for _single level_ configuration (ex: `config.hello`). ```ruby - config.payment_processing.schedule = :daily - config.payment_processing.retries = 3 + config.x.payment_processing.schedule = :daily + config.x.payment_processing.retries = 3 config.super_debugger = true ``` These configuration points are then available through the configuration object: ```ruby - Rails.configuration.payment_processing.schedule # => :daily - Rails.configuration.payment_processing.retries # => 3 - Rails.configuration.super_debugger # => true - Rails.configuration.super_debugger.not_set # => nil + Rails.configuration.x.payment_processing.schedule # => :daily + Rails.configuration.x.payment_processing.retries # => 3 + Rails.configuration.x.payment_processing.not_set # => nil + Rails.configuration.super_debugger # => true ``` You can also use `Rails::Application.config_for` to load whole configuration files: @@ -1210,13 +1499,13 @@ Search Engines Indexing ----------------------- Sometimes, you may want to prevent some pages of your application to be visible -on search sites like Google, Bing, Yahoo or Duck Duck Go. The robots that index +on search sites like Google, Bing, Yahoo, or Duck Duck Go. The robots that index these sites will first analyze the `http://your-site.com/robots.txt` file to know which pages it is allowed to index. Rails creates this file for you inside the `/public` folder. By default, it allows search engines to index all pages of your application. If you want to block -indexing on all pages of you application, use this: +indexing on all pages of your application, use this: ``` User-agent: * @@ -1231,18 +1520,18 @@ Evented File System Monitor If the [listen gem](https://github.com/guard/listen) is loaded Rails uses an evented file system monitor to detect changes when `config.cache_classes` is -false: +`false`: ```ruby group :development do - gem 'listen', '~> 3.0.4' + gem 'listen', '>= 3.0.5', '< 3.2' end ``` Otherwise, in every request Rails walks the application tree to check if anything has changed. -On Linux and Mac OS X no additional gems are needed, but some are required +On Linux and macOS no additional gems are needed, but some are required [for *BSD](https://github.com/guard/listen#on-bsd) and [for Windows](https://github.com/guard/listen#on-windows). |