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diff --git a/guides/source/5_0_release_notes.md b/guides/source/5_0_release_notes.md new file mode 100644 index 0000000000..d63921507d --- /dev/null +++ b/guides/source/5_0_release_notes.md @@ -0,0 +1,1096 @@ +**DO NOT READ THIS FILE ON GITHUB, GUIDES ARE PUBLISHED ON https://guides.rubyonrails.org.** + +Ruby on Rails 5.0 Release Notes +=============================== + +Highlights in Rails 5.0: + +* Action Cable +* Rails API +* Active Record Attributes API +* Test Runner +* Exclusive use of `rails` CLI over Rake +* Sprockets 3 +* Turbolinks 5 +* Ruby 2.2.2+ required + +These release notes cover only the major changes. To learn about various bug +fixes and changes, please refer to the change logs or check out the [list of +commits](https://github.com/rails/rails/commits/5-0-stable) in the main Rails +repository on GitHub. + +-------------------------------------------------------------------------------- + +Upgrading to Rails 5.0 +---------------------- + +If you're upgrading an existing application, it's a great idea to have good test +coverage before going in. You should also first upgrade to Rails 4.2 in case you +haven't and make sure your application still runs as expected before attempting +an update to Rails 5.0. A list of things to watch out for when upgrading is +available in the +[Upgrading Ruby on Rails](upgrading_ruby_on_rails.html#upgrading-from-rails-4-2-to-rails-5-0) +guide. + + +Major Features +-------------- + +### Action Cable + +Action Cable is a new framework in Rails 5. It seamlessly integrates +[WebSockets](https://en.wikipedia.org/wiki/WebSocket) with the rest of your +Rails application. + +Action Cable allows for real-time features to be written in Ruby in the +same style and form as the rest of your Rails application, while still being +performant and scalable. It's a full-stack offering that provides both a +client-side JavaScript framework and a server-side Ruby framework. You have +access to your full domain model written with Active Record or your ORM of +choice. + +See the [Action Cable Overview](action_cable_overview.html) guide for more +information. + +### API Applications + +Rails can now be used to create slimmed down API only applications. +This is useful for creating and serving APIs similar to [Twitter](https://dev.twitter.com) or [GitHub](https://developer.github.com) API, +that can be used to serve public facing, as well as, for custom applications. + +You can generate a new api Rails app using: + +```bash +$ rails new my_api --api +``` + +This will do three main things: + +- Configure your application to start with a more limited set of middleware + than normal. Specifically, it will not include any middleware primarily useful + for browser applications (like cookies support) by default. +- Make `ApplicationController` inherit from `ActionController::API` instead of + `ActionController::Base`. As with middleware, this will leave out any Action + Controller modules that provide functionalities primarily used by browser + applications. +- Configure the generators to skip generating views, helpers, and assets when + you generate a new resource. + +The application provides a base for APIs, +that can then be [configured to pull in functionality](api_app.html) as suitable for the application's needs. + +See the [Using Rails for API-only Applications](api_app.html) guide for more +information. + +### Active Record attributes API + +Defines an attribute with a type on a model. It will override the type of existing attributes if needed. +This allows control over how values are converted to and from SQL when assigned to a model. +It also changes the behavior of values passed to `ActiveRecord::Base.where`, which lets use our domain objects across much of Active Record, +without having to rely on implementation details or monkey patching. + +Some things that you can achieve with this: + +- The type detected by Active Record can be overridden. +- A default can also be provided. +- Attributes do not need to be backed by a database column. + +```ruby + +# db/schema.rb +create_table :store_listings, force: true do |t| + t.decimal :price_in_cents + t.string :my_string, default: "original default" +end + +# app/models/store_listing.rb +class StoreListing < ActiveRecord::Base +end + +store_listing = StoreListing.new(price_in_cents: '10.1') + +# before +store_listing.price_in_cents # => BigDecimal.new(10.1) +StoreListing.new.my_string # => "original default" + +class StoreListing < ActiveRecord::Base + attribute :price_in_cents, :integer # custom type + attribute :my_string, :string, default: "new default" # default value + attribute :my_default_proc, :datetime, default: -> { Time.now } # default value + attribute :field_without_db_column, :integer, array: true +end + +# after +store_listing.price_in_cents # => 10 +StoreListing.new.my_string # => "new default" +StoreListing.new.my_default_proc # => 2015-05-30 11:04:48 -0600 +model = StoreListing.new(field_without_db_column: ["1", "2", "3"]) +model.attributes # => {field_without_db_column: [1, 2, 3]} +``` + +**Creating Custom Types:** + +You can define your own custom types, as long as they respond +to the methods defined on the value type. The method `deserialize` or +`cast` will be called on your type object, with raw input from the +database or from your controllers. This is useful, for example, when doing custom conversion, +like Money data. + +**Querying:** + +When `ActiveRecord::Base.where` is called, it will +use the type defined by the model class to convert the value to SQL, +calling `serialize` on your type object. + +This gives the objects ability to specify, how to convert values when performing SQL queries. + +**Dirty Tracking:** + +The type of an attribute is given the opportunity to change how dirty +tracking is performed. + +See its +[documentation](http://api.rubyonrails.org/v5.0.1/classes/ActiveRecord/Attributes/ClassMethods.html) +for a detailed write up. + + +### Test Runner + +A new test runner has been introduced to enhance the capabilities of running tests from Rails. +To use this test runner simply type `bin/rails test`. + +Test Runner is inspired from `RSpec`, `minitest-reporters`, `maxitest` and others. +It includes some of these notable advancements: + +- Run a single test using line number of test. +- Run multiple tests pinpointing to line number of tests. +- Improved failure messages, which also add ease of re-running failed tests. +- Fail fast using `-f` option, to stop tests immediately on occurrence of failure, +instead of waiting for the suite to complete. +- Defer test output until the end of a full test run using the `-d` option. +- Complete exception backtrace output using `-b` option. +- Integration with minitest to allow options like `-s` for test seed data, +`-n` for running specific test by name, `-v` for better verbose output and so forth. +- Colored test output. + +Railties +-------- + +Please refer to the [Changelog][railties] for detailed changes. + +### Removals + +* Removed debugger support, use byebug instead. `debugger` is not supported by + Ruby + 2.2. ([commit](https://github.com/rails/rails/commit/93559da4826546d07014f8cfa399b64b4a143127)) + +* Removed deprecated `test:all` and `test:all:db` tasks. + ([commit](https://github.com/rails/rails/commit/f663132eef0e5d96bf2a58cec9f7c856db20be7c)) + +* Removed deprecated `Rails::Rack::LogTailer`. + ([commit](https://github.com/rails/rails/commit/c564dcb75c191ab3d21cc6f920998b0d6fbca623)) + +* Removed deprecated `RAILS_CACHE` constant. + ([commit](https://github.com/rails/rails/commit/b7f856ce488ef8f6bf4c12bb549f462cb7671c08)) + +* Removed deprecated `serve_static_assets` configuration. + ([commit](https://github.com/rails/rails/commit/463b5d7581ee16bfaddf34ca349b7d1b5878097c)) + +* Removed the documentation tasks `doc:app`, `doc:rails`, and `doc:guides`. + ([commit](https://github.com/rails/rails/commit/cd7cc5254b090ccbb84dcee4408a5acede25ef2a)) + +* Removed `Rack::ContentLength` middleware from the default + stack. ([Commit](https://github.com/rails/rails/commit/56903585a099ab67a7acfaaef0a02db8fe80c450)) + +### Deprecations + +* Deprecated `config.static_cache_control` in favor of + `config.public_file_server.headers`. + ([Pull Request](https://github.com/rails/rails/pull/19135)) + +* Deprecated `config.serve_static_files` in favor of `config.public_file_server.enabled`. + ([Pull Request](https://github.com/rails/rails/pull/22173)) + +* Deprecated the tasks in the `rails` task namespace in favor of the `app` namespace. + (e.g. `rails:update` and `rails:template` tasks are renamed to `app:update` and `app:template`.) + ([Pull Request](https://github.com/rails/rails/pull/23439)) + +### Notable changes + +* Added Rails test runner `bin/rails test`. + ([Pull Request](https://github.com/rails/rails/pull/19216)) + +* Newly generated applications and plugins get a `README.md` in Markdown. + ([commit](https://github.com/rails/rails/commit/89a12c931b1f00b90e74afffcdc2fc21f14ca663), + [Pull Request](https://github.com/rails/rails/pull/22068)) + +* Added `bin/rails restart` task to restart your Rails app by touching `tmp/restart.txt`. + ([Pull Request](https://github.com/rails/rails/pull/18965)) + +* Added `bin/rails initializers` task to print out all defined initializers in + the order they are invoked by Rails. + ([Pull Request](https://github.com/rails/rails/pull/19323)) + +* Added `bin/rails dev:cache` to enable or disable caching in development mode. + ([Pull Request](https://github.com/rails/rails/pull/20961)) + +* Added `bin/update` script to update the development environment automatically. + ([Pull Request](https://github.com/rails/rails/pull/20972)) + +* Proxy Rake tasks through `bin/rails`. + ([Pull Request](https://github.com/rails/rails/pull/22457), + [Pull Request](https://github.com/rails/rails/pull/22288)) + +* New applications are generated with the evented file system monitor enabled + on Linux and macOS. The feature can be opted out by passing + `--skip-listen` to the generator. + ([commit](https://github.com/rails/rails/commit/de6ad5665d2679944a9ee9407826ba88395a1003), + [commit](https://github.com/rails/rails/commit/94dbc48887bf39c241ee2ce1741ee680d773f202)) + +* Generate applications with an option to log to STDOUT in production + using the environment variable `RAILS_LOG_TO_STDOUT`. + ([Pull Request](https://github.com/rails/rails/pull/23734)) + +* Enable HSTS with IncludeSudomains header for new applications. + ([Pull Request](https://github.com/rails/rails/pull/23852)) + +* The application generator writes a new file `config/spring.rb`, which tells + Spring to watch additional common files. + ([commit](https://github.com/rails/rails/commit/b04d07337fd7bc17e88500e9d6bcd361885a45f8)) + +* Added `--skip-action-mailer` to skip Action Mailer while generating new app. + ([Pull Request](https://github.com/rails/rails/pull/18288)) + +* Removed `tmp/sessions` directory and the clear rake task associated with it. + ([Pull Request](https://github.com/rails/rails/pull/18314)) + +* Changed `_form.html.erb` generated by scaffold generator to use local variables. + ([Pull Request](https://github.com/rails/rails/pull/13434)) + +* Disabled autoloading of classes in production environment. + ([commit](https://github.com/rails/rails/commit/a71350cae0082193ad8c66d65ab62e8bb0b7853b)) + +Action Pack +----------- + +Please refer to the [Changelog][action-pack] for detailed changes. + +### Removals + +* Removed `ActionDispatch::Request::Utils.deep_munge`. + ([commit](https://github.com/rails/rails/commit/52cf1a71b393486435fab4386a8663b146608996)) + +* Removed `ActionController::HideActions`. + ([Pull Request](https://github.com/rails/rails/pull/18371)) + +* Removed `respond_to` and `respond_with` placeholder methods, this functionality + has been extracted to the + [responders](https://github.com/plataformatec/responders) gem. + ([commit](https://github.com/rails/rails/commit/afd5e9a7ff0072e482b0b0e8e238d21b070b6280)) + +* Removed deprecated assertion files. + ([commit](https://github.com/rails/rails/commit/92e27d30d8112962ee068f7b14aa7b10daf0c976)) + +* Removed deprecated usage of string keys in URL helpers. + ([commit](https://github.com/rails/rails/commit/34e380764edede47f7ebe0c7671d6f9c9dc7e809)) + +* Removed deprecated `only_path` option on `*_path` helpers. + ([commit](https://github.com/rails/rails/commit/e4e1fd7ade47771067177254cb133564a3422b8a)) + +* Removed deprecated `NamedRouteCollection#helpers`. + ([commit](https://github.com/rails/rails/commit/2cc91c37bc2e32b7a04b2d782fb8f4a69a14503f)) + +* Removed deprecated support to define routes with `:to` option that doesn't contain `#`. + ([commit](https://github.com/rails/rails/commit/1f3b0a8609c00278b9a10076040ac9c90a9cc4a6)) + +* Removed deprecated `ActionDispatch::Response#to_ary`. + ([commit](https://github.com/rails/rails/commit/4b19d5b7bcdf4f11bd1e2e9ed2149a958e338c01)) + +* Removed deprecated `ActionDispatch::Request#deep_munge`. + ([commit](https://github.com/rails/rails/commit/7676659633057dacd97b8da66e0d9119809b343e)) + +* Removed deprecated + `ActionDispatch::Http::Parameters#symbolized_path_parameters`. + ([commit](https://github.com/rails/rails/commit/7fe7973cd8bd119b724d72c5f617cf94c18edf9e)) + +* Removed deprecated option `use_route` in controller tests. + ([commit](https://github.com/rails/rails/commit/e4cfd353a47369dd32198b0e67b8cbb2f9a1c548)) + +* Removed `assigns` and `assert_template`. Both methods have been extracted + into the + [rails-controller-testing](https://github.com/rails/rails-controller-testing) + gem. + ([Pull Request](https://github.com/rails/rails/pull/20138)) + +### Deprecations + +* Deprecated all `*_filter` callbacks in favor of `*_action` callbacks. + ([Pull Request](https://github.com/rails/rails/pull/18410)) + +* Deprecated `*_via_redirect` integration test methods. Use `follow_redirect!` + manually after the request call for the same behavior. + ([Pull Request](https://github.com/rails/rails/pull/18693)) + +* Deprecated `AbstractController#skip_action_callback` in favor of individual + skip_callback methods. + ([Pull Request](https://github.com/rails/rails/pull/19060)) + +* Deprecated `:nothing` option for `render` method. + ([Pull Request](https://github.com/rails/rails/pull/20336)) + +* Deprecated passing first parameter as `Hash` and default status code for + `head` method. + ([Pull Request](https://github.com/rails/rails/pull/20407)) + +* Deprecated using strings or symbols for middleware class names. Use class + names instead. + ([commit](https://github.com/rails/rails/commit/83b767ce)) + +* Deprecated accessing mime types via constants (eg. `Mime::HTML`). Use the + subscript operator with a symbol instead (eg. `Mime[:html]`). + ([Pull Request](https://github.com/rails/rails/pull/21869)) + +* Deprecated `redirect_to :back` in favor of `redirect_back`, which accepts a + required `fallback_location` argument, thus eliminating the possibility of a + `RedirectBackError`. + ([Pull Request](https://github.com/rails/rails/pull/22506)) + +* `ActionDispatch::IntegrationTest` and `ActionController::TestCase` deprecate positional arguments in favor of + keyword arguments. ([Pull Request](https://github.com/rails/rails/pull/18323)) + +* Deprecated `:controller` and `:action` path parameters. + ([Pull Request](https://github.com/rails/rails/pull/23980)) + +* Deprecated env method on controller instances. + ([commit](https://github.com/rails/rails/commit/05934d24aff62d66fc62621aa38dae6456e276be)) + +* `ActionDispatch::ParamsParser` is deprecated and was removed from the + middleware stack. To configure the parameter parsers use + `ActionDispatch::Request.parameter_parsers=`. + ([commit](https://github.com/rails/rails/commit/38d2bf5fd1f3e014f2397898d371c339baa627b1), + [commit](https://github.com/rails/rails/commit/5ed38014811d4ce6d6f957510b9153938370173b)) + +### Notable changes + +* Added `ActionController::Renderer` to render arbitrary templates + outside controller actions. + ([Pull Request](https://github.com/rails/rails/pull/18546)) + +* Migrating to keyword arguments syntax in `ActionController::TestCase` and + `ActionDispatch::Integration` HTTP request methods. + ([Pull Request](https://github.com/rails/rails/pull/18323)) + +* Added `http_cache_forever` to Action Controller, so we can cache a response + that never gets expired. + ([Pull Request](https://github.com/rails/rails/pull/18394)) + +* Provide friendlier access to request variants. + ([Pull Request](https://github.com/rails/rails/pull/18939)) + +* For actions with no corresponding templates, render `head :no_content` + instead of raising an error. + ([Pull Request](https://github.com/rails/rails/pull/19377)) + +* Added the ability to override default form builder for a controller. + ([Pull Request](https://github.com/rails/rails/pull/19736)) + +* Added support for API only apps. + `ActionController::API` is added as a replacement of + `ActionController::Base` for this kind of applications. + ([Pull Request](https://github.com/rails/rails/pull/19832)) + +* Make `ActionController::Parameters` no longer inherits from + `HashWithIndifferentAccess`. + ([Pull Request](https://github.com/rails/rails/pull/20868)) + +* Make it easier to opt in to `config.force_ssl` and `config.ssl_options` by + making them less dangerous to try and easier to disable. + ([Pull Request](https://github.com/rails/rails/pull/21520)) + +* Added the ability of returning arbitrary headers to `ActionDispatch::Static`. + ([Pull Request](https://github.com/rails/rails/pull/19135)) + +* Changed the `protect_from_forgery` prepend default to `false`. + ([commit](https://github.com/rails/rails/commit/39794037817703575c35a75f1961b01b83791191)) + +* `ActionController::TestCase` will be moved to its own gem in Rails 5.1. Use + `ActionDispatch::IntegrationTest` instead. + ([commit](https://github.com/rails/rails/commit/4414c5d1795e815b102571425974a8b1d46d932d)) + +* Rails generates weak ETags by default. + ([Pull Request](https://github.com/rails/rails/pull/17573)) + +* Controller actions without an explicit `render` call and with no + corresponding templates will render `head :no_content` implicitly + instead of raising an error. + (Pull Request [1](https://github.com/rails/rails/pull/19377), + [2](https://github.com/rails/rails/pull/23827)) + +* Added an option for per-form CSRF tokens. + ([Pull Request](https://github.com/rails/rails/pull/22275)) + +* Added request encoding and response parsing to integration tests. + ([Pull Request](https://github.com/rails/rails/pull/21671)) + +* Add `ActionController#helpers` to get access to the view context + at the controller level. + ([Pull Request](https://github.com/rails/rails/pull/24866)) + +* Discarded flash messages get removed before storing into session. + ([Pull Request](https://github.com/rails/rails/pull/18721)) + +* Added support for passing collection of records to `fresh_when` and + `stale?`. + ([Pull Request](https://github.com/rails/rails/pull/18374)) + +* `ActionController::Live` became an `ActiveSupport::Concern`. That + means it can't be just included in other modules without extending + them with `ActiveSupport::Concern` or `ActionController::Live` + won't take effect in production. Some people may be using another + module to include some special `Warden`/`Devise` authentication + failure handling code as well since the middleware can't catch a + `:warden` thrown by a spawned thread which is the case when using + `ActionController::Live`. + ([More details in this issue](https://github.com/rails/rails/issues/25581)) + +* Introduce `Response#strong_etag=` and `#weak_etag=` and analogous + options for `fresh_when` and `stale?`. + ([Pull Request](https://github.com/rails/rails/pull/24387)) + +Action View +------------- + +Please refer to the [Changelog][action-view] for detailed changes. + +### Removals + +* Removed deprecated `AbstractController::Base::parent_prefixes`. + ([commit](https://github.com/rails/rails/commit/34bcbcf35701ca44be559ff391535c0dd865c333)) + +* Removed `ActionView::Helpers::RecordTagHelper`, this functionality + has been extracted to the + [record_tag_helper](https://github.com/rails/record_tag_helper) gem. + ([Pull Request](https://github.com/rails/rails/pull/18411)) + +* Removed `:rescue_format` option for `translate` helper since it's no longer + supported by I18n. + ([Pull Request](https://github.com/rails/rails/pull/20019)) + +### Notable Changes + +* Changed the default template handler from `ERB` to `Raw`. + ([commit](https://github.com/rails/rails/commit/4be859f0fdf7b3059a28d03c279f03f5938efc80)) + +* Collection rendering can cache and fetches multiple partials at once. + ([Pull Request](https://github.com/rails/rails/pull/18948), + [commit](https://github.com/rails/rails/commit/e93f0f0f133717f9b06b1eaefd3442bd0ff43985)) + +* Added wildcard matching to explicit dependencies. + ([Pull Request](https://github.com/rails/rails/pull/20904)) + +* Make `disable_with` the default behavior for submit tags. Disables the + button on submit to prevent double submits. + ([Pull Request](https://github.com/rails/rails/pull/21135)) + +* Partial template name no longer has to be a valid Ruby identifier. + ([commit](https://github.com/rails/rails/commit/da9038e)) + +* The `datetime_tag` helper now generates an input tag with the type of + `datetime-local`. + ([Pull Request](https://github.com/rails/rails/pull/25469)) + +* Allow blocks while rendering with the `render partial:` helper. + ([Pull Request](https://github.com/rails/rails/pull/17974)) + +Action Mailer +------------- + +Please refer to the [Changelog][action-mailer] for detailed changes. + +### Removals + +* Removed deprecated `*_path` helpers in email views. + ([commit](https://github.com/rails/rails/commit/d282125a18c1697a9b5bb775628a2db239142ac7)) + +* Removed deprecated `deliver` and `deliver!` methods. + ([commit](https://github.com/rails/rails/commit/755dcd0691f74079c24196135f89b917062b0715)) + +### Notable changes + +* Template lookup now respects default locale and I18n fallbacks. + ([commit](https://github.com/rails/rails/commit/ecb1981b)) + +* Added `_mailer` suffix to mailers created via generator, following the same + naming convention used in controllers and jobs. + ([Pull Request](https://github.com/rails/rails/pull/18074)) + +* Added `assert_enqueued_emails` and `assert_no_enqueued_emails`. + ([Pull Request](https://github.com/rails/rails/pull/18403)) + +* Added `config.action_mailer.deliver_later_queue_name` configuration to set + the mailer queue name. + ([Pull Request](https://github.com/rails/rails/pull/18587)) + +* Added support for fragment caching in Action Mailer views. + Added new config option `config.action_mailer.perform_caching` to determine + whether your templates should perform caching or not. + ([Pull Request](https://github.com/rails/rails/pull/22825)) + + +Active Record +------------- + +Please refer to the [Changelog][active-record] for detailed changes. + +### Removals + +* Removed deprecated behavior allowing nested arrays to be passed as query + values. ([Pull Request](https://github.com/rails/rails/pull/17919)) + +* Removed deprecated `ActiveRecord::Tasks::DatabaseTasks#load_schema`. This + method was replaced by `ActiveRecord::Tasks::DatabaseTasks#load_schema_for`. + ([commit](https://github.com/rails/rails/commit/ad783136d747f73329350b9bb5a5e17c8f8800da)) + +* Removed deprecated `serialized_attributes`. + ([commit](https://github.com/rails/rails/commit/82043ab53cb186d59b1b3be06122861758f814b2)) + +* Removed deprecated automatic counter caches on `has_many :through`. + ([commit](https://github.com/rails/rails/commit/87c8ce340c6c83342df988df247e9035393ed7a0)) + +* Removed deprecated `sanitize_sql_hash_for_conditions`. + ([commit](https://github.com/rails/rails/commit/3a59dd212315ebb9bae8338b98af259ac00bbef3)) + +* Removed deprecated `Reflection#source_macro`. + ([commit](https://github.com/rails/rails/commit/ede8c199a85cfbb6457d5630ec1e285e5ec49313)) + +* Removed deprecated `symbolized_base_class` and `symbolized_sti_name`. + ([commit](https://github.com/rails/rails/commit/9013e28e52eba3a6ffcede26f85df48d264b8951)) + +* Removed deprecated `ActiveRecord::Base.disable_implicit_join_references=`. + ([commit](https://github.com/rails/rails/commit/0fbd1fc888ffb8cbe1191193bf86933110693dfc)) + +* Removed deprecated access to connection specification using a string accessor. + ([commit](https://github.com/rails/rails/commit/efdc20f36ccc37afbb2705eb9acca76dd8aabd4f)) + +* Removed deprecated support to preload instance-dependent associations. + ([commit](https://github.com/rails/rails/commit/4ed97979d14c5e92eb212b1a629da0a214084078)) + +* Removed deprecated support for PostgreSQL ranges with exclusive lower bounds. + ([commit](https://github.com/rails/rails/commit/a076256d63f64d194b8f634890527a5ed2651115)) + +* Removed deprecation when modifying a relation with cached Arel. + This raises an `ImmutableRelation` error instead. + ([commit](https://github.com/rails/rails/commit/3ae98181433dda1b5e19910e107494762512a86c)) + +* Removed `ActiveRecord::Serialization::XmlSerializer` from core. This feature + has been extracted into the + [activemodel-serializers-xml](https://github.com/rails/activemodel-serializers-xml) + gem. ([Pull Request](https://github.com/rails/rails/pull/21161)) + +* Removed support for the legacy `mysql` database adapter from core. Most users should + be able to use `mysql2`. It will be converted to a separate gem when we find someone + to maintain it. ([Pull Request 1](https://github.com/rails/rails/pull/22642), + [Pull Request 2](https://github.com/rails/rails/pull/22715)) + +* Removed support for the `protected_attributes` gem. + ([commit](https://github.com/rails/rails/commit/f4fbc0301021f13ae05c8e941c8efc4ae351fdf9)) + +* Removed support for PostgreSQL versions below 9.1. + ([Pull Request](https://github.com/rails/rails/pull/23434)) + +* Removed support for `activerecord-deprecated_finders` gem. + ([commit](https://github.com/rails/rails/commit/78dab2a8569408658542e462a957ea5a35aa4679)) + +* Removed `ActiveRecord::ConnectionAdapters::Column::TRUE_VALUES` constant. + ([commit](https://github.com/rails/rails/commit/a502703c3d2151d4d3b421b29fefdac5ad05df61)) + +### Deprecations + +* Deprecated passing a class as a value in a query. Users should pass strings + instead. ([Pull Request](https://github.com/rails/rails/pull/17916)) + +* Deprecated returning `false` as a way to halt Active Record callback + chains. The recommended way is to + `throw(:abort)`. ([Pull Request](https://github.com/rails/rails/pull/17227)) + +* Deprecated `ActiveRecord::Base.errors_in_transactional_callbacks=`. + ([commit](https://github.com/rails/rails/commit/07d3d402341e81ada0214f2cb2be1da69eadfe72)) + +* Deprecated `Relation#uniq` use `Relation#distinct` instead. + ([commit](https://github.com/rails/rails/commit/adfab2dcf4003ca564d78d4425566dd2d9cd8b4f)) + +* Deprecated the PostgreSQL `:point` type in favor of a new one which will return + `Point` objects instead of an `Array` + ([Pull Request](https://github.com/rails/rails/pull/20448)) + +* Deprecated force association reload by passing a truthy argument to + association method. + ([Pull Request](https://github.com/rails/rails/pull/20888)) + +* Deprecated the keys for association `restrict_dependent_destroy` errors in favor + of new key names. + ([Pull Request](https://github.com/rails/rails/pull/20668)) + +* Synchronize behavior of `#tables`. + ([Pull Request](https://github.com/rails/rails/pull/21601)) + +* Deprecated `SchemaCache#tables`, `SchemaCache#table_exists?` and + `SchemaCache#clear_table_cache!` in favor of their new data source + counterparts. + ([Pull Request](https://github.com/rails/rails/pull/21715)) + +* Deprecated `connection.tables` on the SQLite3 and MySQL adapters. + ([Pull Request](https://github.com/rails/rails/pull/21601)) + +* Deprecated passing arguments to `#tables` - the `#tables` method of some + adapters (mysql2, sqlite3) would return both tables and views while others + (postgresql) just return tables. To make their behavior consistent, + `#tables` will return only tables in the future. + ([Pull Request](https://github.com/rails/rails/pull/21601)) + +* Deprecated `table_exists?` - The `#table_exists?` method would check both + tables and views. To make their behavior consistent with `#tables`, + `#table_exists?` will check only tables in the future. + ([Pull Request](https://github.com/rails/rails/pull/21601)) + +* Deprecate sending the `offset` argument to `find_nth`. Please use the + `offset` method on relation instead. + ([Pull Request](https://github.com/rails/rails/pull/22053)) + +* Deprecated `{insert|update|delete}_sql` in `DatabaseStatements`. + Use the `{insert|update|delete}` public methods instead. + ([Pull Request](https://github.com/rails/rails/pull/23086)) + +* Deprecated `use_transactional_fixtures` in favor of + `use_transactional_tests` for more clarity. + ([Pull Request](https://github.com/rails/rails/pull/19282)) + +* Deprecated passing a column to `ActiveRecord::Connection#quote`. + ([commit](https://github.com/rails/rails/commit/7bb620869725ad6de603f6a5393ee17df13aa96c)) + +* Added an option `end` to `find_in_batches` that complements the `start` + parameter to specify where to stop batch processing. + ([Pull Request](https://github.com/rails/rails/pull/12257)) + + +### Notable changes + +* Added a `foreign_key` option to `references` while creating the table. + ([commit](https://github.com/rails/rails/commit/99a6f9e60ea55924b44f894a16f8de0162cf2702)) + +* New attributes + API. ([commit](https://github.com/rails/rails/commit/8c752c7ac739d5a86d4136ab1e9d0142c4041e58)) + +* Added `:_prefix`/`:_suffix` option to `enum` definition. + ([Pull Request](https://github.com/rails/rails/pull/19813), + [Pull Request](https://github.com/rails/rails/pull/20999)) + +* Added `#cache_key` to `ActiveRecord::Relation`. + ([Pull Request](https://github.com/rails/rails/pull/20884)) + +* Changed the default `null` value for `timestamps` to `false`. + ([commit](https://github.com/rails/rails/commit/a939506f297b667291480f26fa32a373a18ae06a)) + +* Added `ActiveRecord::SecureToken` in order to encapsulate generation of + unique tokens for attributes in a model using `SecureRandom`. + ([Pull Request](https://github.com/rails/rails/pull/18217)) + +* Added `:if_exists` option for `drop_table`. + ([Pull Request](https://github.com/rails/rails/pull/18597)) + +* Added `ActiveRecord::Base#accessed_fields`, which can be used to quickly + discover which fields were read from a model when you are looking to only + select the data you need from the database. + ([commit](https://github.com/rails/rails/commit/be9b68038e83a617eb38c26147659162e4ac3d2c)) + +* Added the `#or` method on `ActiveRecord::Relation`, allowing use of the OR + operator to combine WHERE or HAVING clauses. + ([commit](https://github.com/rails/rails/commit/b0b37942d729b6bdcd2e3178eda7fa1de203b3d0)) + +* Added `ActiveRecord::Base.suppress` to prevent the receiver from being saved + during the given block. + ([Pull Request](https://github.com/rails/rails/pull/18910)) + +* `belongs_to` will now trigger a validation error by default if the + association is not present. You can turn this off on a per-association basis + with `optional: true`. Also deprecate `required` option in favor of `optional` + for `belongs_to`. + ([Pull Request](https://github.com/rails/rails/pull/18937)) + +* Added `config.active_record.dump_schemas` to configure the behavior of + `db:structure:dump`. + ([Pull Request](https://github.com/rails/rails/pull/19347)) + +* Added `config.active_record.warn_on_records_fetched_greater_than` option. + ([Pull Request](https://github.com/rails/rails/pull/18846)) + +* Added a native JSON data type support in MySQL. + ([Pull Request](https://github.com/rails/rails/pull/21110)) + +* Added support for dropping indexes concurrently in PostgreSQL. + ([Pull Request](https://github.com/rails/rails/pull/21317)) + +* Added `#views` and `#view_exists?` methods on connection adapters. + ([Pull Request](https://github.com/rails/rails/pull/21609)) + +* Added `ActiveRecord::Base.ignored_columns` to make some columns + invisible from Active Record. + ([Pull Request](https://github.com/rails/rails/pull/21720)) + +* Added `connection.data_sources` and `connection.data_source_exists?`. + These methods determine what relations can be used to back Active Record + models (usually tables and views). + ([Pull Request](https://github.com/rails/rails/pull/21715)) + +* Allow fixtures files to set the model class in the YAML file itself. + ([Pull Request](https://github.com/rails/rails/pull/20574)) + +* Added ability to default to `uuid` as primary key when generating database + migrations. ([Pull Request](https://github.com/rails/rails/pull/21762)) + +* Added `ActiveRecord::Relation#left_joins` and + `ActiveRecord::Relation#left_outer_joins`. + ([Pull Request](https://github.com/rails/rails/pull/12071)) + +* Added `after_{create,update,delete}_commit` callbacks. + ([Pull Request](https://github.com/rails/rails/pull/22516)) + +* Version the API presented to migration classes, so we can change parameter + defaults without breaking existing migrations, or forcing them to be + rewritten through a deprecation cycle. + ([Pull Request](https://github.com/rails/rails/pull/21538)) + +* `ApplicationRecord` is a new superclass for all app models, analogous to app + controllers subclassing `ApplicationController` instead of + `ActionController::Base`. This gives apps a single spot to configure app-wide + model behavior. + ([Pull Request](https://github.com/rails/rails/pull/22567)) + +* Added ActiveRecord `#second_to_last` and `#third_to_last` methods. + ([Pull Request](https://github.com/rails/rails/pull/23583)) + +* Added ability to annotate database objects (tables, columns, indexes) + with comments stored in database metadata for PostgreSQL & MySQL. + ([Pull Request](https://github.com/rails/rails/pull/22911)) + +* Added prepared statements support to `mysql2` adapter, for mysql2 0.4.4+, + Previously this was only supported on the deprecated `mysql` legacy adapter. + To enable, set `prepared_statements: true` in `config/database.yml`. + ([Pull Request](https://github.com/rails/rails/pull/23461)) + +* Added ability to call `ActionRecord::Relation#update` on relation objects + which will run validations on callbacks on all objects in the relation. + ([Pull Request](https://github.com/rails/rails/pull/11898)) + +* Added `:touch` option to the `save` method so that records can be saved without + updating timestamps. + ([Pull Request](https://github.com/rails/rails/pull/18225)) + +* Added expression indexes and operator classes support for PostgreSQL. + ([commit](https://github.com/rails/rails/commit/edc2b7718725016e988089b5fb6d6fb9d6e16882)) + +* Added `:index_errors` option to add indexes to errors of nested attributes. + ([Pull Request](https://github.com/rails/rails/pull/19686)) + +* Added support for bidirectional destroy dependencies. + ([Pull Request](https://github.com/rails/rails/pull/18548)) + +* Added support for `after_commit` callbacks in transactional tests. + ([Pull Request](https://github.com/rails/rails/pull/18458)) + +* Added `foreign_key_exists?` method to see if a foreign key exists on a table + or not. + ([Pull Request](https://github.com/rails/rails/pull/18662)) + +* Added `:time` option to `touch` method to touch records with different time + than the current time. + ([Pull Request](https://github.com/rails/rails/pull/18956)) + +* Change transaction callbacks to not swallow errors. + Before this change any errors raised inside a transaction callback + were getting rescued and printed in the logs, unless you used + the (newly deprecated) `raise_in_transactional_callbacks = true` option. + + Now these errors are not rescued anymore and just bubble up, matching the + behavior of other callbacks. + ([commit](https://github.com/rails/rails/commit/07d3d402341e81ada0214f2cb2be1da69eadfe72)) + +Active Model +------------ + +Please refer to the [Changelog][active-model] for detailed changes. + +### Removals + +* Removed deprecated `ActiveModel::Dirty#reset_#{attribute}` and + `ActiveModel::Dirty#reset_changes`. + ([Pull Request](https://github.com/rails/rails/commit/37175a24bd508e2983247ec5d011d57df836c743)) + +* Removed XML serialization. This feature has been extracted into the + [activemodel-serializers-xml](https://github.com/rails/activemodel-serializers-xml) gem. + ([Pull Request](https://github.com/rails/rails/pull/21161)) + +* Removed `ActionController::ModelNaming` module. + ([Pull Request](https://github.com/rails/rails/pull/18194)) + +### Deprecations + +* Deprecated returning `false` as a way to halt Active Model and + `ActiveModel::Validations` callback chains. The recommended way is to + `throw(:abort)`. ([Pull Request](https://github.com/rails/rails/pull/17227)) + +* Deprecated `ActiveModel::Errors#get`, `ActiveModel::Errors#set` and + `ActiveModel::Errors#[]=` methods that have inconsistent behavior. + ([Pull Request](https://github.com/rails/rails/pull/18634)) + +* Deprecated the `:tokenizer` option for `validates_length_of`, in favor of + plain Ruby. + ([Pull Request](https://github.com/rails/rails/pull/19585)) + +* Deprecated `ActiveModel::Errors#add_on_empty` and `ActiveModel::Errors#add_on_blank` + with no replacement. + ([Pull Request](https://github.com/rails/rails/pull/18996)) + +### Notable changes + +* Added `ActiveModel::Errors#details` to determine what validator has failed. + ([Pull Request](https://github.com/rails/rails/pull/18322)) + +* Extracted `ActiveRecord::AttributeAssignment` to `ActiveModel::AttributeAssignment` + allowing to use it for any object as an includable module. + ([Pull Request](https://github.com/rails/rails/pull/10776)) + +* Added `ActiveModel::Dirty#[attr_name]_previously_changed?` and + `ActiveModel::Dirty#[attr_name]_previous_change` to improve access + to recorded changes after the model has been saved. + ([Pull Request](https://github.com/rails/rails/pull/19847)) + +* Validate multiple contexts on `valid?` and `invalid?` at once. + ([Pull Request](https://github.com/rails/rails/pull/21069)) + +* Change `validates_acceptance_of` to accept `true` as default value + apart from `1`. + ([Pull Request](https://github.com/rails/rails/pull/18439)) + +Active Job +----------- + +Please refer to the [Changelog][active-job] for detailed changes. + +### Notable changes + +* `ActiveJob::Base.deserialize` delegates to the job class. This allows jobs + to attach arbitrary metadata when they get serialized and read it back when + they get performed. + ([Pull Request](https://github.com/rails/rails/pull/18260)) + +* Add ability to configure the queue adapter on a per job basis without + affecting each other. + ([Pull Request](https://github.com/rails/rails/pull/16992)) + +* A generated job now inherits from `app/jobs/application_job.rb` by default. + ([Pull Request](https://github.com/rails/rails/pull/19034)) + +* Allow `DelayedJob`, `Sidekiq`, `qu`, `que`, and `queue_classic` to report + the job id back to `ActiveJob::Base` as `provider_job_id`. + ([Pull Request](https://github.com/rails/rails/pull/20064), + [Pull Request](https://github.com/rails/rails/pull/20056), + [commit](https://github.com/rails/rails/commit/68e3279163d06e6b04e043f91c9470e9259bbbe0)) + +* Implement a simple `AsyncJob` processor and associated `AsyncAdapter` that + queue jobs to a `concurrent-ruby` thread pool. + ([Pull Request](https://github.com/rails/rails/pull/21257)) + +* Change the default adapter from inline to async. It's a better default as + tests will then not mistakenly come to rely on behavior happening + synchronously. + ([commit](https://github.com/rails/rails/commit/625baa69d14881ac49ba2e5c7d9cac4b222d7022)) + +Active Support +-------------- + +Please refer to the [Changelog][active-support] for detailed changes. + +### Removals + +* Removed deprecated `ActiveSupport::JSON::Encoding::CircularReferenceError`. + ([commit](https://github.com/rails/rails/commit/d6e06ea8275cdc3f126f926ed9b5349fde374b10)) + +* Removed deprecated methods `ActiveSupport::JSON::Encoding.encode_big_decimal_as_string=` + and `ActiveSupport::JSON::Encoding.encode_big_decimal_as_string`. + ([commit](https://github.com/rails/rails/commit/c8019c0611791b2716c6bed48ef8dcb177b7869c)) + +* Removed deprecated `ActiveSupport::SafeBuffer#prepend`. + ([commit](https://github.com/rails/rails/commit/e1c8b9f688c56aaedac9466a4343df955b4a67ec)) + +* Removed deprecated methods from `Kernel`. `silence_stderr`, `silence_stream`, + `capture` and `quietly`. + ([commit](https://github.com/rails/rails/commit/481e49c64f790e46f4aff3ed539ed227d2eb46cb)) + +* Removed deprecated `active_support/core_ext/big_decimal/yaml_conversions` + file. + ([commit](https://github.com/rails/rails/commit/98ea19925d6db642731741c3b91bd085fac92241)) + +* Removed deprecated methods `ActiveSupport::Cache::Store.instrument` and + `ActiveSupport::Cache::Store.instrument=`. + ([commit](https://github.com/rails/rails/commit/a3ce6ca30ed0e77496c63781af596b149687b6d7)) + +* Removed deprecated `Class#superclass_delegating_accessor`. + Use `Class#class_attribute` instead. + ([Pull Request](https://github.com/rails/rails/pull/16938)) + +* Removed deprecated `ThreadSafe::Cache`. Use `Concurrent::Map` instead. + ([Pull Request](https://github.com/rails/rails/pull/21679)) + +* Removed `Object#itself` as it is implemented in Ruby 2.2. + ([Pull Request](https://github.com/rails/rails/pull/18244)) + +### Deprecations + +* Deprecated `MissingSourceFile` in favor of `LoadError`. + ([commit](https://github.com/rails/rails/commit/734d97d2)) + +* Deprecated `alias_method_chain` in favour of `Module#prepend` introduced in + Ruby 2.0. + ([Pull Request](https://github.com/rails/rails/pull/19434)) + +* Deprecated `ActiveSupport::Concurrency::Latch` in favor of + `Concurrent::CountDownLatch` from concurrent-ruby. + ([Pull Request](https://github.com/rails/rails/pull/20866)) + +* Deprecated `:prefix` option of `number_to_human_size` with no replacement. + ([Pull Request](https://github.com/rails/rails/pull/21191)) + +* Deprecated `Module#qualified_const_` in favour of the builtin + `Module#const_` methods. + ([Pull Request](https://github.com/rails/rails/pull/17845)) + +* Deprecated passing string to define callback. + ([Pull Request](https://github.com/rails/rails/pull/22598)) + +* Deprecated `ActiveSupport::Cache::Store#namespaced_key`, + `ActiveSupport::Cache::MemCachedStore#escape_key`, and + `ActiveSupport::Cache::FileStore#key_file_path`. + Use `normalize_key` instead. + ([Pull Request](https://github.com/rails/rails/pull/22215), + [commit](https://github.com/rails/rails/commit/a8f773b0)) + +* Deprecated `ActiveSupport::Cache::LocaleCache#set_cache_value` in favor of `write_cache_value`. + ([Pull Request](https://github.com/rails/rails/pull/22215)) + +* Deprecated passing arguments to `assert_nothing_raised`. + ([Pull Request](https://github.com/rails/rails/pull/23789)) + +* Deprecated `Module.local_constants` in favor of `Module.constants(false)`. + ([Pull Request](https://github.com/rails/rails/pull/23936)) + + +### Notable changes + +* Added `#verified` and `#valid_message?` methods to + `ActiveSupport::MessageVerifier`. + ([Pull Request](https://github.com/rails/rails/pull/17727)) + +* Changed the way in which callback chains can be halted. The preferred method + to halt a callback chain from now on is to explicitly `throw(:abort)`. + ([Pull Request](https://github.com/rails/rails/pull/17227)) + +* New config option + `config.active_support.halt_callback_chains_on_return_false` to specify + whether ActiveRecord, ActiveModel, and ActiveModel::Validations callback + chains can be halted by returning `false` in a 'before' callback. + ([Pull Request](https://github.com/rails/rails/pull/17227)) + +* Changed the default test order from `:sorted` to `:random`. + ([commit](https://github.com/rails/rails/commit/5f777e4b5ee2e3e8e6fd0e2a208ec2a4d25a960d)) + +* Added `#on_weekend?`, `#on_weekday?`, `#next_weekday`, `#prev_weekday` methods to `Date`, + `Time`, and `DateTime`. + ([Pull Request](https://github.com/rails/rails/pull/18335), + [Pull Request](https://github.com/rails/rails/pull/23687)) + +* Added `same_time` option to `#next_week` and `#prev_week` for `Date`, `Time`, + and `DateTime`. + ([Pull Request](https://github.com/rails/rails/pull/18335)) + +* Added `#prev_day` and `#next_day` counterparts to `#yesterday` and + `#tomorrow` for `Date`, `Time`, and `DateTime`. + ([Pull Request](https://github.com/rails/rails/pull/18335)) + +* Added `SecureRandom.base58` for generation of random base58 strings. + ([commit](https://github.com/rails/rails/commit/b1093977110f18ae0cafe56c3d99fc22a7d54d1b)) + +* Added `file_fixture` to `ActiveSupport::TestCase`. + It provides a simple mechanism to access sample files in your test cases. + ([Pull Request](https://github.com/rails/rails/pull/18658)) + +* Added `#without` on `Enumerable` and `Array` to return a copy of an + enumerable without the specified elements. + ([Pull Request](https://github.com/rails/rails/pull/19157)) + +* Added `ActiveSupport::ArrayInquirer` and `Array#inquiry`. + ([Pull Request](https://github.com/rails/rails/pull/18939)) + +* Added `ActiveSupport::TimeZone#strptime` to allow parsing times as if + from a given timezone. + ([commit](https://github.com/rails/rails/commit/a5e507fa0b8180c3d97458a9b86c195e9857d8f6)) + +* Added `Integer#positive?` and `Integer#negative?` query methods + in the vein of `Integer#zero?`. + ([commit](https://github.com/rails/rails/commit/e54277a45da3c86fecdfa930663d7692fd083daa)) + +* Added a bang version to `ActiveSupport::OrderedOptions` get methods which will raise + an `KeyError` if the value is `.blank?`. + ([Pull Request](https://github.com/rails/rails/pull/20208)) + +* Added `Time.days_in_year` to return the number of days in the given year, or the + current year if no argument is provided. + ([commit](https://github.com/rails/rails/commit/2f4f4d2cf1e4c5a442459fc250daf66186d110fa)) + +* Added an evented file watcher to asynchronously detect changes in the + application source code, routes, locales, etc. + ([Pull Request](https://github.com/rails/rails/pull/22254)) + +* Added thread_m/cattr_accessor/reader/writer suite of methods for declaring + class and module variables that live per-thread. + ([Pull Request](https://github.com/rails/rails/pull/22630)) + +* Added `Array#second_to_last` and `Array#third_to_last` methods. + ([Pull Request](https://github.com/rails/rails/pull/23583)) + +* Publish `ActiveSupport::Executor` and `ActiveSupport::Reloader` APIs to allow + components and libraries to manage, and participate in, the execution of + application code, and the application reloading process. + ([Pull Request](https://github.com/rails/rails/pull/23807)) + +* `ActiveSupport::Duration` now supports ISO8601 formatting and parsing. + ([Pull Request](https://github.com/rails/rails/pull/16917)) + +* `ActiveSupport::JSON.decode` now supports parsing ISO8601 local times when + `parse_json_times` is enabled. + ([Pull Request](https://github.com/rails/rails/pull/23011)) + +* `ActiveSupport::JSON.decode` now return `Date` objects for date strings. + ([Pull Request](https://github.com/rails/rails/pull/23011)) + +* Added ability to `TaggedLogging` to allow loggers to be instantiated multiple + times so that they don't share tags with each other. + ([Pull Request](https://github.com/rails/rails/pull/9065)) + +Credits +------- + +See the +[full list of contributors to Rails](http://contributors.rubyonrails.org/) for +the many people who spent many hours making Rails, the stable and robust +framework it is. Kudos to all of them. + +[railties]: https://github.com/rails/rails/blob/5-0-stable/railties/CHANGELOG.md +[action-pack]: https://github.com/rails/rails/blob/5-0-stable/actionpack/CHANGELOG.md +[action-view]: https://github.com/rails/rails/blob/5-0-stable/actionview/CHANGELOG.md +[action-mailer]: https://github.com/rails/rails/blob/5-0-stable/actionmailer/CHANGELOG.md +[action-cable]: https://github.com/rails/rails/blob/5-0-stable/actioncable/CHANGELOG.md +[active-record]: https://github.com/rails/rails/blob/5-0-stable/activerecord/CHANGELOG.md +[active-model]: https://github.com/rails/rails/blob/5-0-stable/activemodel/CHANGELOG.md +[active-support]: https://github.com/rails/rails/blob/5-0-stable/activesupport/CHANGELOG.md +[active-job]: https://github.com/rails/rails/blob/5-0-stable/activejob/CHANGELOG.md |