diff options
Diffstat (limited to 'guides/source')
52 files changed, 2534 insertions, 870 deletions
diff --git a/guides/source/2_2_release_notes.md b/guides/source/2_2_release_notes.md index b11aaa15a8..019da08687 100644 --- a/guides/source/2_2_release_notes.md +++ b/guides/source/2_2_release_notes.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + Ruby on Rails 2.2 Release Notes =============================== diff --git a/guides/source/2_3_release_notes.md b/guides/source/2_3_release_notes.md index 20566c9155..4ac1529e76 100644 --- a/guides/source/2_3_release_notes.md +++ b/guides/source/2_3_release_notes.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + Ruby on Rails 2.3 Release Notes =============================== diff --git a/guides/source/3_0_release_notes.md b/guides/source/3_0_release_notes.md index 2630207c0f..3d7966e50b 100644 --- a/guides/source/3_0_release_notes.md +++ b/guides/source/3_0_release_notes.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + Ruby on Rails 3.0 Release Notes =============================== @@ -138,7 +140,7 @@ More Information: - [Rails Edge Architecture](http://yehudakatz.com/2009/06/11/r [Arel](http://github.com/brynary/arel) (or Active Relation) has been taken on as the underpinnings of Active Record and is now required for Rails. Arel provides an SQL abstraction that simplifies out Active Record and provides the underpinnings for the relation functionality in Active Record. -More information: - [Why I wrote Arel](http://magicscalingsprinkles.wordpress.com/2010/01/28/why-i-wrote-arel/.) +More information: - [Why I wrote Arel](https://web.archive.org/web/20120718093140/http://magicscalingsprinkles.wordpress.com/2010/01/28/why-i-wrote-arel/) ### Mail Extraction diff --git a/guides/source/3_1_release_notes.md b/guides/source/3_1_release_notes.md index b7ed285b96..8728750966 100644 --- a/guides/source/3_1_release_notes.md +++ b/guides/source/3_1_release_notes.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + Ruby on Rails 3.1 Release Notes =============================== diff --git a/guides/source/3_2_release_notes.md b/guides/source/3_2_release_notes.md index c5db0262e9..0b28aac9ce 100644 --- a/guides/source/3_2_release_notes.md +++ b/guides/source/3_2_release_notes.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + Ruby on Rails 3.2 Release Notes =============================== diff --git a/guides/source/4_0_release_notes.md b/guides/source/4_0_release_notes.md index 84a65df2bc..5f52c33746 100644 --- a/guides/source/4_0_release_notes.md +++ b/guides/source/4_0_release_notes.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + Ruby on Rails 4.0 Release Notes =============================== diff --git a/guides/source/4_1_release_notes.md b/guides/source/4_1_release_notes.md index c7877a9cb5..dbc151c0ca 100644 --- a/guides/source/4_1_release_notes.md +++ b/guides/source/4_1_release_notes.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + Ruby on Rails 4.1 Release Notes =============================== diff --git a/guides/source/4_2_release_notes.md b/guides/source/4_2_release_notes.md index 8553cffa9d..faff1add9f 100644 --- a/guides/source/4_2_release_notes.md +++ b/guides/source/4_2_release_notes.md @@ -1,23 +1,23 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + Ruby on Rails 4.2 Release Notes =============================== Highlights in Rails 4.2: -* Active Job, Action Mailer #deliver_later +* Active Job +* Asynchronous mails * Adequate Record * Web Console * Foreign key support -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/master) in the main Rails -repository on GitHub. +These release notes cover only the major changes. To learn about other +features, bug fixes, and changes, please refer to the changelogs or check out +the [list of commits](https://github.com/rails/rails/commits/4-2-stable) in +the main Rails repository on GitHub. -------------------------------------------------------------------------------- -NOTE: This document is a work in progress, please help to improve this by sending -a [pull request](https://github.com/rails/rails/edit/master/guides/source/4_2_release_notes.md). - Upgrading to Rails 4.2 ---------------------- @@ -25,96 +25,115 @@ 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 4.1 in case you haven't and make sure your application still runs as expected before attempting to upgrade to Rails 4.2. A list of things to watch out for when upgrading is -available in the guide: [Upgrading Ruby on -Rails](upgrading_ruby_on_rails.html#upgrading-from-rails-4-1-to-rails-4-2) +available in the guide [Upgrading Ruby on +Rails](upgrading_ruby_on_rails.html#upgrading-from-rails-4-1-to-rails-4-2). Major Features -------------- -### Active Job, Action Mailer #deliver_later +### Active Job -Active Job is a new framework in Rails 4.2. It is an adapter layer on top of +Active Job is a new framework in Rails 4.2. It is a common interface on top of queuing systems like [Resque](https://github.com/resque/resque), [Delayed Job](https://github.com/collectiveidea/delayed_job), [Sidekiq](https://github.com/mperham/sidekiq), and more. -You can write your jobs with the Active Job API, and it'll run on all these -queues with no changes (it comes pre-configured with an inline runner). +Jobs written with the Active Job API run on any of the supported queues thanks +to their respective adapters. Active Job comes pre-configured with an inline +runner that executes jobs right away. + +Jobs often need to take Active Record objects as arguments. Active Job passes +object references as URIs (uniform resource identifiers) instead of marshaling +the object itself. The new [Global ID](https://github.com/rails/globalid) +library builds URIs and looks up the objects they reference. Passing Active +Record objects as job arguments just works by using Global ID internally. + +For example, if `trashable` is an Active Record object, then this job runs +just fine with no serialization involved: + +```ruby +class TrashableCleanupJob < ActiveJob::Base + def perform(trashable, depth) + trashable.cleanup(depth) + end +end +``` + +See the [Active Job Basics](active_job_basics.html) guide for more +information. + +### Asynchronous Mails -Building on top of Active Job, Action Mailer now comes with a `#deliver_later` -method, which adds your email to be sent as a job to a queue, so it doesn't -bog down the controller or model. +Building on top of Active Job, Action Mailer now comes with a `deliver_later` +method that sends emails via the queue, so it doesn't block the controller or +model if the queue is asynchronous (the default inline queue blocks). -The new GlobalID library makes it easy to pass Active Record objects to jobs by -serializing them in a generic form. This means you no longer have to manually -pack and unpack your Active Records by passing ids. Just give the job the -Active Record object, and it'll serialize it using GlobalID, and deserialize -it at run time. +Sending emails right away is still possible with `deliver_now`. ### Adequate Record -Adequate Record is a set of refactorings that make Active Record `find` and -`find_by` methods and some association queries up to 2x faster. +Adequate Record is a set of performance improvements in Active Record that makes +common `find` and `find_by` calls and some association queries up to 2x faster. -It works by caching SQL query patterns while executing the Active Record calls. -The cache helps skip parts of the computation involved in the transformation of -the calls into SQL queries. More details in [Aaron Patterson's +It works by caching common SQL queries as prepared statements and reusing them +on similar calls, skipping most of the query-generation work on subsequent +calls. For more details, please refer to [Aaron Patterson's blog post](http://tenderlovemaking.com/2014/02/19/adequaterecord-pro-like-activerecord.html). -Nothing special has to be done to activate this feature. Most `find` and -`find_by` calls and association queries will use it automatically. Examples: +Active Record will automatically take advantage of this feature on +supported operations without any user involvement or code changes. Here are +some examples of supported operations: ```ruby -Post.find 1 # caches query pattern -Post.find 2 # uses the cached pattern +Post.find(1) # First call generates and cache the prepared statement +Post.find(2) # Subsequent calls reuse the cached prepared statement -Post.find_by_title 'first post' # caches query pattern -Post.find_by_title 'second post' # uses the cached pattern +Post.find_by_title('first post') +Post.find_by_title('second post') -post.comments # caches query pattern -post.comments(true) # uses cached pattern +Post.find_by(title: 'first post') +Post.find_by(title: 'second post') + +post.comments +post.comments(true) ``` -The caching is not used in the following scenarios: +It's important to highlight that, as the examples above suggest, the prepared +statements do not cache the values passed in the method calls; rather, they +have placeholders for them. + +Caching is not used in the following scenarios: - The model has a default scope -- The model uses single table inheritance to inherit from another model -- `find` with a list of ids. eg: +- The model uses single table inheritance +- `find` with a list of ids, e.g.: ```ruby - Post.find(1,2,3) - OR - Post.find [1,2] + # not cached + Post.find(1, 2, 3) + Post.find([1,2]) ``` - `find_by` with SQL fragments: ```ruby - Post.find_by "published_at < ?", 2.weeks.ago + Post.find_by('published_at < ?', 2.weeks.ago) ``` ### Web Console -New applications generated from Rails 4.2 now come with the Web Console gem by -default. - -Web Console is a set of debugging tools for your Rails application. It will add -an interactive console on every error page, a `console` view helper and a VT100 -compatible terminal. - -The interactive console on the error pages lets you execute code where the -exception originated. It's quite handy to introspect the state that led to the -error. - -The `console` view helper launches an interactive console within the context of -the view where it is invoked. +New applications generated with Rails 4.2 now come with the [Web +Console](https://github.com/rails/web-console) gem by default. Web Console adds +an interactive Ruby console on every error page and provides a `console` view +and controller helpers. -Finally, you can launch a VT100 terminal that runs `rails console`. If you need -to create or modify existing test data, you can do that straight from the -browser. +The interactive console on error pages lets you execute code in the context of +the place where the exception originated. The `console` helper, if called +anywhere in a view or controller, launches an interactive console with the final +context, once rendering has completed. -### Foreign key support +### Foreign Key Support The migration DSL now supports adding and removing foreign keys. They are dumped to `schema.rb` as well. At this time, only the `mysql`, `mysql2` and `postgresql` @@ -149,18 +168,18 @@ individual components for new deprecations in this release. The following changes may require immediate action upon upgrade. -### `render` with a String argument +### `render` with a String Argument -Previously, calling `render "foo/bar"` in a controller action is equivalent to -`render file: "foo/bar"`. In Rails 4.2, this has been changed to mean `render template: "foo/bar"` -instead. If you need to render a file, please change your code to use the -explicit form (`render file: "foo/bar"`) instead. +Previously, calling `render "foo/bar"` in a controller action was equivalent to +`render file: "foo/bar"`. In Rails 4.2, this has been changed to mean +`render template: "foo/bar"` instead. If you need to render a file, please +change your code to use the explicit form (`render file: "foo/bar"`) instead. -### `respond_with` / class-level `respond_to` +### `respond_with` / Class-Level `respond_to` -`respond_with` and the corresponding class-level `respond_to` have been moved to -the `responders` gem. To use the following, add `gem 'responders', '~> 2.0'` to -your Gemfile: +`respond_with` and the corresponding class-level `respond_to` have been moved +to the [responders](https://github.com/plataformatec/responders) gem. Add +`gem 'responders', '~> 2.0'` to your Gemfile to use it: ```ruby # app/controllers/users_controller.rb @@ -191,61 +210,47 @@ class UsersController < ApplicationController end ``` -### Default host for `rails server` +### Default Host for `rails server` Due to a [change in Rack](https://github.com/rack/rack/commit/28b014484a8ac0bbb388e7eaeeef159598ec64fc), `rails server` now listens on `localhost` instead of `0.0.0.0` by default. This -should have minimal impact on the standard development workflow as both http://127.0.0.1:3000 -and http://localhost:3000 will continue to work as before on your own machine. +should have minimal impact on the standard development workflow as both +http://127.0.0.1:3000 and http://localhost:3000 will continue to work as before +on your own machine. -However, with this change you will no longer be able to access the Rails server -from a different machine (e.g. your development environment is in a virtual -machine and you would like to access it from the host machine), you would need -to start the server with `rails server -b 0.0.0.0` to restore the old behavior. +However, with this change you will no longer be able to access the Rails +server from a different machine, for example if your development environment +is in a virtual machine and you would like to access it from the host machine. +In such cases, please start the server with `rails server -b 0.0.0.0` to +restore the old behavior. If you do this, be sure to configure your firewall properly such that only trusted machines on your network can access your development server. -### Production logging - -The default log level in the `production` environment is now `:debug`. This -makes it consistent with the other environments, and ensures plenty of -information is available to diagnose problems. - -It can be returned to the previous level, `:info`, in the environment -configuration: - -```ruby -# config/environments/production.rb - -# Decrease the log volume. -config.log_level = :info -``` - ### HTML Sanitizer The HTML sanitizer has been replaced with a new, more robust, implementation -built upon Loofah and Nokogiri. The new sanitizer is more secure and its -sanitization is more powerful and flexible. +built upon [Loofah](https://github.com/flavorjones/loofah) and +[Nokogiri](https://github.com/sparklemotion/nokogiri). The new sanitizer is +more secure and its sanitization is more powerful and flexible. -With a new sanitization algorithm, the sanitized output will change for certain +Due to the new algorithm, the sanitized output may be different for certain pathological inputs. -If you have particular need for the exact output of the old sanitizer, you can -add `rails-deprecated_sanitizer` to your Gemfile, and it will automatically -replace the new implementation. Because it is opt-in, the legacy gem will not -give deprecation warnings. +If you have a particular need for the exact output of the old sanitizer, you +can add the [rails-deprecated_sanitizer](https://github.com/kaspth/rails-deprecated_sanitizer) +gem to the `Gemfile`, to have the old behavior. The gem does not issue +deprecation warnings because it is opt-in. `rails-deprecated_sanitizer` will be supported for Rails 4.2 only; it will not be maintained for Rails 5.0. -See [the blog post](http://blog.plataformatec.com.br/2014/07/the-new-html-sanitizer-in-rails-4-2/) -for more detail on the changes in the new sanitizer. +See [this blog post](http://blog.plataformatec.com.br/2014/07/the-new-html-sanitizer-in-rails-4-2/) +for more details on the changes in the new sanitizer. ### `assert_select` -`assert_select` is now based on Nokogiri, making it (TODO: betterer). - +`assert_select` is now based on [Nokogiri](https://github.com/sparklemotion/nokogiri). As a result, some previously-valid selectors are now unsupported. If your application is using any of these spellings, you will need to update them: @@ -253,8 +258,13 @@ application is using any of these spellings, you will need to update them: non-alphanumeric characters. ``` - a[href=/] => a[href="/"] - a[href$=/] => a[href$="/"] + # before + a[href=/] + a[href$=/] + + # now + a[href="/"] + a[href$="/"] ``` * DOMs built from HTML source containing invalid HTML with improperly @@ -308,6 +318,16 @@ Please refer to the [Changelog][railties] for detailed changes. ### Deprecations +* Deprecated missing `config.log_level` for production environments. + ([Pull Request](https://github.com/rails/rails/pull/16622)) + +* Deprecated `rake test:all` in favor of `rake test` as it now run all tests + in the `test` folder. + ([Pull Request](https://github.com/rails/rails/pull/17348)) + +* Deprecated `rake test:all:db` in favor of `rake test:db`. + ([Pull Request](https://github.com/rails/rails/pull/17348)) + * Deprecated `Rails::Rack::LogTailer` without replacement. ([Commit](https://github.com/rails/rails/commit/84a13e019e93efaa8994b3f8303d635a7702dbce)) @@ -319,9 +339,6 @@ Please refer to the [Changelog][railties] for detailed changes. * Added a `required` option to the model generator for associations. ([Pull Request](https://github.com/rails/rails/pull/16062)) -* Introduced an `after_bundle` callback for use in Rails templates. - ([Pull Request](https://github.com/rails/rails/pull/16359)) - * Introduced the `x` namespace for defining custom configuration options: ```ruby @@ -361,20 +378,23 @@ Please refer to the [Changelog][railties] for detailed changes. ([Pull Request](https://github.com/rails/rails/pull/16129)) -* Introduce a `--skip-turbolinks` option in the app generator to not generate - any turbolinks integration. +* Introduced a `--skip-turbolinks` option in the app generator to not generate + turbolinks integration. ([Commit](https://github.com/rails/rails/commit/bf17c8a531bc8059d50ad731398002a3e7162a7d)) -* Introduced a `bin/setup` script to enable automated setup code when +* Introduced a `bin/setup` script as a convention for automated setup code when bootstrapping an application. ([Pull Request](https://github.com/rails/rails/pull/15189)) -* Changed default value for `config.assets.digest` to `true` in development. +* Changed the default value for `config.assets.digest` to `true` in development. ([Pull Request](https://github.com/rails/rails/pull/15155)) * Introduced an API to register new extensions for `rake notes`. ([Pull Request](https://github.com/rails/rails/pull/14379)) +* Introduced an `after_bundle` callback for use in Rails templates. + ([Pull Request](https://github.com/rails/rails/pull/16359)) + * Introduced `Rails.gem_version` as a convenience method to return `Gem::Version.new(Rails.version)`. ([Pull Request](https://github.com/rails/rails/pull/14101)) @@ -387,10 +407,11 @@ Please refer to the [Changelog][action-pack] for detailed changes. ### Removals -* `respond_with` and the class-level `respond_to` were removed from Rails and +* `respond_with` and the class-level `respond_to` have been removed from Rails and moved to the `responders` gem (version 2.0). Add `gem 'responders', '~> 2.0'` to your `Gemfile` to continue using these features. - ([Pull Request](https://github.com/rails/rails/pull/16526)) + ([Pull Request](https://github.com/rails/rails/pull/16526), + [More Details](http://guides.rubyonrails.org/upgrading_ruby_on_rails.html#responders)) * Removed deprecated `AbstractController::Helpers::ClassMethods::MissingHelperError` in favor of `AbstractController::Helpers::MissingHelperError`. @@ -406,7 +427,7 @@ Please refer to the [Changelog][action-pack] for detailed changes. ([Commit](https://github.com/rails/rails-dom-testing/commit/b12850bc5ff23ba4b599bf2770874dd4f11bf750)) * Deprecated support for setting the `:to` option of a router to a symbol or a - string that does not contain a `#` character: + string that does not contain a "#" character: ```ruby get '/posts', to: MyRackApp => (No change necessary) @@ -417,22 +438,22 @@ Please refer to the [Changelog][action-pack] for detailed changes. ([Commit](https://github.com/rails/rails/commit/cc26b6b7bccf0eea2e2c1a9ebdcc9d30ca7390d9)) -### Notable changes +* Deprecated support for string keys in URL helpers: -* Rails will now automatically include the template's digest in ETags. - ([Pull Request](https://github.com/rails/rails/pull/16527)) + ```ruby + # bad + root_path('controller' => 'posts', 'action' => 'index') -* `render nothing: true` or rendering a `nil` body no longer add a single - space padding to the response body. - ([Pull Request](https://github.com/rails/rails/pull/14883)) + # good + root_path(controller: 'posts', action: 'index') + ``` -* Introduced the `always_permitted_parameters` option to configure which - parameters are permitted globally. The default value of this configuration - is `['controller', 'action']`. - ([Pull Request](https://github.com/rails/rails/pull/15933)) + ([Pull Request](https://github.com/rails/rails/pull/17743)) -* The `*_filter` family methods have been removed from the documentation. Their - usage is discouraged in favor of the `*_action` family methods: +### Notable changes + +* The `*_filter` family of methods have been removed from the documentation. Their + usage is discouraged in favor of the `*_action` family of methods: ``` after_filter => after_action @@ -457,16 +478,28 @@ Please refer to the [Changelog][action-pack] for detailed changes. (Commit [1](https://github.com/rails/rails/commit/6c5f43bab8206747a8591435b2aa0ff7051ad3de), [2](https://github.com/rails/rails/commit/489a8f2a44dc9cea09154ee1ee2557d1f037c7d4)) -* Added HTTP method `MKCALENDAR` from RFC-4791 +* `render nothing: true` or rendering a `nil` body no longer add a single + space padding to the response body. + ([Pull Request](https://github.com/rails/rails/pull/14883)) + +* Rails now automatically includes the template's digest in ETags. + ([Pull Request](https://github.com/rails/rails/pull/16527)) + +* Segments that are passed into URL helpers are now automatically escaped. + ([Commit](https://github.com/rails/rails/commit/5460591f0226a9d248b7b4f89186bd5553e7768f)) + +* Introduced the `always_permitted_parameters` option to configure which + parameters are permitted globally. The default value of this configuration + is `['controller', 'action']`. + ([Pull Request](https://github.com/rails/rails/pull/15933)) + +* Added the HTTP method `MKCALENDAR` from [RFC 4791](https://tools.ietf.org/html/rfc4791). ([Pull Request](https://github.com/rails/rails/pull/15121)) * `*_fragment.action_controller` notifications now include the controller and action name in the payload. ([Pull Request](https://github.com/rails/rails/pull/14137)) -* Segments that are passed into URL helpers are now automatically escaped. - ([Commit](https://github.com/rails/rails/commit/5460591f0226a9d248b7b4f89186bd5553e7768f)) - * Improved the Routing Error page with fuzzy matching for route search. ([Pull Request](https://github.com/rails/rails/pull/14619)) @@ -481,21 +514,19 @@ Please refer to the [Changelog][action-pack] for detailed changes. serving assets from your Rails server in production. ([Pull Request](https://github.com/rails/rails/pull/16466)) -* The way `assert_select` works has changed; specifically a different library - is used to interpret CSS selectors, build the transient DOM that the - selectors are applied against, and to extract the data from that DOM. These - changes should only affect edge cases. Examples: - * Values in attribute selectors may need to be quoted if they contain - non-alphanumeric characters. - * DOMs built from HTML source containing invalid HTML with improperly - nested elements may differ. - * If the data selected contains entities, the value selected for comparison - used to be raw (e.g. `AT&T`), and now is evaluated - (e.g. `AT&T`). +* When calling the `process` helpers in an integration test the path needs to have + a leading slash. Previously you could omit it but that was a byproduct of the + implementation and not an intentional feature, e.g.: + ```ruby + test "list all posts" do + get "/posts" + assert_response :success + end + ``` Action View -------------- +----------- Please refer to the [Changelog][action-view] for detailed changes. @@ -516,16 +547,16 @@ Please refer to the [Changelog][action-view] for detailed changes. `render file: "foo/bar"`. ([Pull Request](https://github.com/rails/rails/pull/16888)) -* Introduced a `#{partial_name}_iteration` special local variable for use with - partials that are rendered with a collection. It provides access to the - current state of the iteration via the `#index`, `#size`, `#first?` and - `#last?` methods. - ([Pull Request](https://github.com/rails/rails/pull/7698)) - * The form helpers no longer generate a `<div>` element with inline CSS around the hidden fields. ([Pull Request](https://github.com/rails/rails/pull/14738)) +* Introduced a `#{partial_name}_iteration` special local variable for use with + partials that are rendered with a collection. It provides access to the + current state of the iteration via the `index`, `size`, `first?` and + `last?` methods. + ([Pull Request](https://github.com/rails/rails/pull/7698)) + * Placeholder I18n follows the same convention as `label` I18n. ([Pull Request](https://github.com/rails/rails/pull/16438)) @@ -545,6 +576,10 @@ Please refer to the [Changelog][action-mailer] for detailed changes. ### Notable changes +* `link_to` and `url_for` generate absolute URLs by default in templates, + it is no longer needed to pass `only_path: false`. + ([Commit](https://github.com/rails/rails/commit/9685080a7677abfa5d288a81c3e078368c6bb67c)) + * Introduced `deliver_later` which enqueues a job on the application's queue to deliver emails asynchronously. ([Pull Request](https://github.com/rails/rails/pull/16485)) @@ -573,32 +608,51 @@ Please refer to the [Changelog][active-record] for detailed changes. * Removed unused `:timestamp` type. Transparently alias it to `:datetime` in all cases. Fixes inconsistencies when column types are sent outside of - `ActiveRecord`, such as for XML serialization. + Active Record, such as for XML serialization. ([Pull Request](https://github.com/rails/rails/pull/15184)) ### Deprecations -* Deprecated `sanitize_sql_hash_for_conditions` without replacement. Using a - `Relation` for performing queries and updates is the prefered API. - ([Commit](https://github.com/rails/rails/commit/d5902c9e)) - * Deprecated swallowing of errors inside `after_commit` and `after_rollback`. ([Pull Request](https://github.com/rails/rails/pull/16537)) +* Deprecated broken support for automatic detection of counter caches on + `has_many :through` associations. You should instead manually specify the + counter cache on the `has_many` and `belongs_to` associations for the + through records. + ([Pull Request](https://github.com/rails/rails/pull/15754)) + +* Deprecated passing Active Record objects to `.find` or `.exists?`. Call + `id` on the objects first. + (Commit [1](https://github.com/rails/rails/commit/d92ae6ccca3bcfd73546d612efaea011270bd270), + [2](https://github.com/rails/rails/commit/d35f0033c7dec2b8d8b52058fb8db495d49596f7)) + +* Deprecated half-baked support for PostgreSQL range values with excluding + beginnings. We currently map PostgreSQL ranges to Ruby ranges. This conversion + is not fully possible because Ruby ranges do not support excluded beginnings. + + The current solution of incrementing the beginning is not correct + and is now deprecated. For subtypes where we don't know how to increment + (e.g. `succ` is not defined) it will raise an `ArgumentError` for ranges + with excluding beginnings. + ([Commit](https://github.com/rails/rails/commit/91949e48cf41af9f3e4ffba3e5eecf9b0a08bfc3)) + * Deprecated calling `DatabaseTasks.load_schema` without a connection. Use `DatabaseTasks.load_schema_current` instead. ([Commit](https://github.com/rails/rails/commit/f15cef67f75e4b52fd45655d7c6ab6b35623c608)) +* Deprecated `sanitize_sql_hash_for_conditions` without replacement. Using a + `Relation` for performing queries and updates is the preferred API. + ([Commit](https://github.com/rails/rails/commit/d5902c9e)) + +* Deprecated `add_timestamps` and `t.timestamps` without passing the `:null` + option. The default of `null: true` will change in Rails 5 to `null: false`. + ([Pull Request](https://github.com/rails/rails/pull/16481)) + * Deprecated `Reflection#source_macro` without replacement as it is no longer needed in Active Record. ([Pull Request](https://github.com/rails/rails/pull/16373)) -* Deprecated broken support for automatic detection of counter caches on - `has_many :through` associations. You should instead manually specify the - counter cache on the `has_many` and `belongs_to` associations for the - through records. - ([Pull Request](https://github.com/rails/rails/pull/15754)) - * Deprecated `serialized_attributes` without replacement. ([Pull Request](https://github.com/rails/rails/pull/15704)) @@ -607,90 +661,78 @@ Please refer to the [Changelog][active-record] for detailed changes. ([Pull Request](https://github.com/rails/rails/pull/15878)) * Deprecated using `.joins`, `.preload` and `.eager_load` with associations - that depends on the instance state (i.e. those defined with a scope that + that depend on the instance state (i.e. those defined with a scope that takes an argument) without replacement. ([Commit](https://github.com/rails/rails/commit/ed56e596a0467390011bc9d56d462539776adac1)) -* Deprecated passing Active Record objects to `.find` or `.exists?`. Call - `#id` on the objects first. - (Commit [1](https://github.com/rails/rails/commit/d92ae6ccca3bcfd73546d612efaea011270bd270), - [2](https://github.com/rails/rails/commit/d35f0033c7dec2b8d8b52058fb8db495d49596f7)) - -* Deprecated half-baked support for PostgreSQL range values with excluding - beginnings. We currently map PostgreSQL ranges to Ruby ranges. This conversion - is not fully possible because the Ruby range does not support excluded - beginnings. - - The current solution of incrementing the beginning is not correct - and is now deprecated. For subtypes where we don't know how to increment - (e.g. `#succ` is not defined) it will raise an `ArgumentError` for ranges - with excluding beginnings. - - ([Commit](https://github.com/rails/rails/commit/91949e48cf41af9f3e4ffba3e5eecf9b0a08bfc3)) - ### Notable changes -* The PostgreSQL adapter now supports the `JSONB` datatype in PostgreSQL 9.4+. - ([Pull Request](https://github.com/rails/rails/pull/16220)) - -* The `#references` method in migrations now supports a `type` option for - specifying the type of the foreign key (e.g. `:uuid`). - ([Pull Request](https://github.com/rails/rails/pull/16231)) +* `SchemaDumper` uses `force: :cascade` on `create_table`. This makes it + possible to reload a schema when foreign keys are in place. * Added a `:required` option to singular associations, which defines a presence validation on the association. ([Pull Request](https://github.com/rails/rails/pull/16056)) -* Introduced `ActiveRecord::Base#validate!` that raises `RecordInvalid` if the - record is invalid. - ([Pull Request](https://github.com/rails/rails/pull/8639)) - -* `ActiveRecord::Base#reload` now behaves the same as `m = Model.find(m.id)`, - meaning that it no longer retains the extra attributes from custom - `select`s. - ([Pull Request](https://github.com/rails/rails/pull/15866)) - -* Introduced the `bin/rake db:purge` task to empty the database for the - current environment. - ([Commit](https://github.com/rails/rails/commit/e2f232aba15937a4b9d14bd91e0392c6d55be58d)) - * `ActiveRecord::Dirty` now detects in-place changes to mutable values. - Serialized attributes on Active Record models will no longer save when + Serialized attributes on Active Record models are no longer saved when unchanged. This also works with other types such as string columns and json columns on PostgreSQL. (Pull Requests [1](https://github.com/rails/rails/pull/15674), [2](https://github.com/rails/rails/pull/15786), [3](https://github.com/rails/rails/pull/15788)) -* Added support for `#pretty_print` in `ActiveRecord::Base` objects. - ([Pull Request](https://github.com/rails/rails/pull/15172)) +* Introduced the `db:purge` Rake task to empty the database for the + current environment. + ([Commit](https://github.com/rails/rails/commit/e2f232aba15937a4b9d14bd91e0392c6d55be58d)) + +* Introduced `ActiveRecord::Base#validate!` that raises + `ActiveRecord::RecordInvalid` if the record is invalid. + ([Pull Request](https://github.com/rails/rails/pull/8639)) + +* Introduced `validate` as an alias for `valid?`. + ([Pull Request](https://github.com/rails/rails/pull/14456)) -* PostgreSQL and SQLite adapters no longer add a default limit of 255 +* `touch` now accepts multiple attributes to be touched at once. + ([Pull Request](https://github.com/rails/rails/pull/14423)) + +* The PostgreSQL adapter now supports the `jsonb` datatype in PostgreSQL 9.4+. + ([Pull Request](https://github.com/rails/rails/pull/16220)) + +* The PostgreSQL and SQLite adapters no longer add a default limit of 255 characters on string columns. ([Pull Request](https://github.com/rails/rails/pull/14579)) +* Added support for the `citext` column type in the PostgreSQL adapter. + ([Pull Request](https://github.com/rails/rails/pull/12523)) + +* Added support for user-created range types in the PostgreSQL adapter. + ([Commit](https://github.com/rails/rails/commit/4cb47167e747e8f9dc12b0ddaf82bdb68c03e032)) + * `sqlite3:///some/path` now resolves to the absolute system path `/some/path`. For relative paths, use `sqlite3:some/path` instead. (Previously, `sqlite3:///some/path` resolved to the relative path - `some/path`. This behaviour was deprecated on Rails 4.1). + `some/path`. This behavior was deprecated on Rails 4.1). ([Pull Request](https://github.com/rails/rails/pull/14569)) -* Introduced `#validate` as an alias for `#valid?`. - ([Pull Request](https://github.com/rails/rails/pull/14456)) - -* `#touch` now accepts multiple attributes to be touched at once. - ([Pull Request](https://github.com/rails/rails/pull/14423)) - * Added support for fractional seconds for MySQL 5.6 and above. (Pull Request [1](https://github.com/rails/rails/pull/8240), [2](https://github.com/rails/rails/pull/14359)) -* Added support for the `citext` column type in PostgreSQL adapter. - ([Pull Request](https://github.com/rails/rails/pull/12523)) +* Added `ActiveRecord::Base#pretty_print` to pretty print models. + ([Pull Request](https://github.com/rails/rails/pull/15172)) -* Added support for user-created range types in PostgreSQL adapter. - ([Commit](https://github.com/rails/rails/commit/4cb47167e747e8f9dc12b0ddaf82bdb68c03e032)) +* `ActiveRecord::Base#reload` now behaves the same as `m = Model.find(m.id)`, + meaning that it no longer retains the extra attributes from custom + `SELECT`s. + ([Pull Request](https://github.com/rails/rails/pull/15866)) + +* `ActiveRecord::Base#reflections` now returns a hash with string keys instead + of symbol keys. ([Pull Request](https://github.com/rails/rails/pull/17718)) +* The `references` method in migrations now supports a `type` option for + specifying the type of the foreign key (e.g. `:uuid`). + ([Pull Request](https://github.com/rails/rails/pull/16231)) Active Model ------------ @@ -708,11 +750,14 @@ Please refer to the [Changelog][active-model] for detailed changes. ([Pull Request](https://github.com/rails/rails/pull/16180)) * Deprecated `ActiveModel::Dirty#reset_changes` in favor of - `#clear_changes_information`. + `clear_changes_information`. ([Pull Request](https://github.com/rails/rails/pull/16180)) ### Notable changes +* Introduced `validate` as an alias for `valid?`. + ([Pull Request](https://github.com/rails/rails/pull/14456)) + * Introduced the `restore_attributes` method in `ActiveModel::Dirty` to restore the changed (dirty) attributes to their previous values. (Pull Request [1](https://github.com/rails/rails/pull/14861), @@ -726,10 +771,6 @@ Please refer to the [Changelog][active-model] for detailed changes. characters if validations are enabled. ([Pull Request](https://github.com/rails/rails/pull/15708)) -* Introduced `#validate` as an alias for `#valid?`. - ([Pull Request](https://github.com/rails/rails/pull/14456)) - - Active Support -------------- @@ -760,12 +801,12 @@ Please refer to the [Changelog][active-support] for detailed changes. ### Notable changes -* Introduced new configuration option `active_support.test_order` for +* Introduced a new configuration option `active_support.test_order` for specifying the order test cases are executed. This option currently defaults to `:sorted` but will be changed to `:random` in Rails 5.0. ([Commit](https://github.com/rails/rails/commit/53e877f7d9291b2bf0b8c425f9e32ef35829f35b)) -* `Object#try` and `Object#try!` can now be used without an explicit receiver. +* `Object#try` and `Object#try!` can now be used without an explicit receiver in the block. ([Commit](https://github.com/rails/rails/commit/5e51bdda59c9ba8e5faf86294e3e431bd45f1830), [Pull Request](https://github.com/rails/rails/pull/17361)) @@ -776,7 +817,7 @@ Please refer to the [Changelog][active-support] for detailed changes. (Commit [1](https://github.com/rails/rails/commit/702ad710b57bef45b081ebf42e6fa70820fdd810), [2](https://github.com/rails/rails/commit/64d91122222c11ad3918cc8e2e3ebc4b0a03448a)) -* `Object#with_options` can now be used without an explicit receiver. +* `Object#with_options` can now be used without an explicit receiver in the block. ([Pull Request](https://github.com/rails/rails/pull/16339)) * Introduced `String#truncate_words` to truncate a string by a number of words. @@ -795,6 +836,7 @@ Please refer to the [Changelog][active-support] for detailed changes. `module Foo; extend ActiveSupport::Concern; end` boilerplate. ([Commit](https://github.com/rails/rails/commit/b16c36e688970df2f96f793a759365b248b582ad)) +* New [guide](constant_autoloading_and_reloading.html) about constant autoloading and reloading. Credits ------- diff --git a/guides/source/_welcome.html.erb b/guides/source/_welcome.html.erb index f2315bfe22..67f5f1cdd5 100644 --- a/guides/source/_welcome.html.erb +++ b/guides/source/_welcome.html.erb @@ -10,10 +10,15 @@ </p> <% else %> <p> - These are the new guides for Rails 4.2 based on <a href="https://github.com/rails/rails/tree/<%= @version %>"><%= @version %></a>. + These are the new guides for Rails 5.0 based on <a href="https://github.com/rails/rails/tree/<%= @version %>"><%= @version %></a>. These guides are designed to make you immediately productive with Rails, and to help you understand how all of the pieces fit together. </p> <% end %> <p> - The guides for earlier releases: <a href="http://guides.rubyonrails.org/v4.1.6/">Rails 4.1.6</a>, <a href="http://guides.rubyonrails.org/v4.0.10/">Rails 4.0.10</a>, <a href="http://guides.rubyonrails.org/v3.2.19/">Rails 3.2.19</a> and <a href="http://guides.rubyonrails.org/v2.3.11/">Rails 2.3.11</a>. +The guides for earlier releases: +<a href="http://guides.rubyonrails.org/v4.2.0/">Rails 4.2.0</a>, +<a href="http://guides.rubyonrails.org/v4.1.8/">Rails 4.1.8</a>, +<a href="http://guides.rubyonrails.org/v4.0.12/">Rails 4.0.12</a>, +<a href="http://guides.rubyonrails.org/v3.2.21/">Rails 3.2.21</a> and +<a href="http://guides.rubyonrails.org/v2.3.11/">Rails 2.3.11</a>. </p> diff --git a/guides/source/action_controller_overview.md b/guides/source/action_controller_overview.md index 1ca0d9ed55..36d1b6de83 100644 --- a/guides/source/action_controller_overview.md +++ b/guides/source/action_controller_overview.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + Action Controller Overview ========================== @@ -112,8 +114,8 @@ NOTE: The actual URL in this example will be encoded as "/clients?ids%5b%5d=1&id The value of `params[:ids]` will now be `["1", "2", "3"]`. Note that parameter values are always strings; Rails makes no attempt to guess or cast the type. -NOTE: Values such as `[]`, `[nil]` or `[nil, nil, ...]` in `params` are replaced -with `nil` for security reasons by default. See [Security Guide](security.html#unsafe-query-generation) +NOTE: Values such as `[nil]` or `[nil, nil, ...]` in `params` are replaced +with `[]` for security reasons by default. See [Security Guide](security.html#unsafe-query-generation) for more information. To send a hash you include the key name inside the brackets: @@ -992,6 +994,11 @@ you would like in a response object. The `ActionController::Live` module allows you to create a persistent connection with a browser. Using this module, you will be able to send arbitrary data to the browser at specific points in time. +NOTE: The default Rails server (WEBrick) is a buffering web server and does not +support streaming. In order to use this feature, you'll need to use a non buffering +server like [Puma](http://puma.io), [Rainbows](http://rainbows.bogomips.org) +or [Passenger](https://www.phusionpassenger.com). + #### Incorporating Live Streaming Including `ActionController::Live` inside of your controller class will provide @@ -1164,67 +1171,10 @@ class ClientsController < ApplicationController end ``` -WARNING: You shouldn't do `rescue_from Exception` or `rescue_from StandardError` unless you have a particular reason as it will cause serious side-effects (e.g. you won't be able to see exception details and tracebacks during development). If you would like to dynamically generate error pages, see [Custom errors page](#custom-errors-page). +WARNING: You shouldn't do `rescue_from Exception` or `rescue_from StandardError` unless you have a particular reason as it will cause serious side-effects (e.g. you won't be able to see exception details and tracebacks during development). NOTE: Certain exceptions are only rescuable from the `ApplicationController` class, as they are raised before the controller gets initialized and the action gets executed. See Pratik Naik's [article](http://m.onkey.org/2008/7/20/rescue-from-dispatching) on the subject for more information. - -### Custom errors page - -You can customize the layout of your error handling using controllers and views. -First define your app own routes to display the errors page. - -* `config/application.rb` - - ```ruby - config.exceptions_app = self.routes - ``` - -* `config/routes.rb` - - ```ruby - match '/404', via: :all, to: 'errors#not_found' - match '/422', via: :all, to: 'errors#unprocessable_entity' - match '/500', via: :all, to: 'errors#server_error' - ``` - -Create the controller and views. - -* `app/controllers/errors_controller.rb` - - ```ruby - class ErrorsController < ActionController::Base - layout 'error' - - def not_found - render status: :not_found - end - - def unprocessable_entity - render status: :unprocessable_entity - end - - def server_error - render status: :server_error - end - end - ``` - -* `app/views` - - ``` - errors/ - not_found.html.erb - unprocessable_entity.html.erb - server_error.html.erb - layouts/ - error.html.erb - ``` - -Do not forget to set the correct status code on the controller as shown before. - -WARNING: You should avoid using the database or any complex operations because the user is already on the error page. Generating another error while on an error page could cause issues like presenting an empty page for the users. - Force HTTPS protocol -------------------- diff --git a/guides/source/action_mailer_basics.md b/guides/source/action_mailer_basics.md index f6c974c87a..c586675ee5 100644 --- a/guides/source/action_mailer_basics.md +++ b/guides/source/action_mailer_basics.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + Action Mailer Basics ==================== @@ -35,10 +37,26 @@ views. ```bash $ bin/rails generate mailer UserMailer create app/mailers/user_mailer.rb +create app/mailers/application_mailer.rb invoke erb create app/views/user_mailer +create app/views/layouts/mailer.text.erb +create app/views/layouts/mailer.html.erb invoke test_unit create test/mailers/user_mailer_test.rb +create test/mailers/previews/user_mailer_preview.rb +``` + +```ruby +# app/mailers/application_mailer.rb +class ApplicationMailer < ActionMailer::Base + default from: "from@example.com" + layout 'mailer' +end + +# app/mailers/user_mailer.rb +class UserMailer < ApplicationMailer +end ``` As you can see, you can generate mailers just like you use other generators with @@ -63,8 +81,7 @@ delivered via email. `app/mailers/user_mailer.rb` contains an empty mailer: ```ruby -class UserMailer < ActionMailer::Base - default from: 'from@example.com' +class UserMailer < ApplicationMailer end ``` @@ -72,7 +89,7 @@ Let's add a method called `welcome_email`, that will send an email to the user's registered email address: ```ruby -class UserMailer < ActionMailer::Base +class UserMailer < ApplicationMailer default from: 'notifications@example.com' def welcome_email(user) @@ -348,7 +365,7 @@ for the HTML version and `welcome_email.text.erb` for the plain text version. To change the default mailer view for your action you do something like: ```ruby -class UserMailer < ActionMailer::Base +class UserMailer < ApplicationMailer default from: 'notifications@example.com' def welcome_email(user) @@ -370,7 +387,7 @@ If you want more flexibility you can also pass a block and render specific templates or even render inline or text without using a template file: ```ruby -class UserMailer < ActionMailer::Base +class UserMailer < ApplicationMailer default from: 'notifications@example.com' def welcome_email(user) @@ -400,7 +417,7 @@ layout. In order to use a different file, call `layout` in your mailer: ```ruby -class UserMailer < ActionMailer::Base +class UserMailer < ApplicationMailer layout 'awesome' # use awesome.(html|text).erb as the layout end ``` @@ -412,7 +429,7 @@ You can also pass in a `layout: 'layout_name'` option to the render call inside the format block to specify different layouts for different formats: ```ruby -class UserMailer < ActionMailer::Base +class UserMailer < ApplicationMailer def welcome_email(user) mail(to: user.email) do |format| format.html { render layout: 'my_layout' } @@ -455,16 +472,7 @@ By using the full URL, your links will now work in your emails. #### generating URLs with `url_for` -You need to pass the `only_path: false` option when using `url_for`. This will -ensure that absolute URLs are generated because the `url_for` view helper will, -by default, generate relative URLs when a `:host` option isn't explicitly -provided. - -```erb -<%= url_for(controller: 'welcome', - action: 'greeting', - only_path: false) %> -``` +`url_for` generate full URL by default in templates. If you did not configure the `:host` option globally make sure to pass it to `url_for`. @@ -476,9 +484,6 @@ If you did not configure the `:host` option globally make sure to pass it to action: 'greeting') %> ``` -NOTE: When you explicitly pass the `:host` Rails will always generate absolute -URLs, so there is no need to pass `only_path: false`. - #### generating URLs with named routes Email clients have no web context and so paths have no base URL to form complete @@ -510,7 +515,7 @@ while delivering emails, you can do this using `delivery_method_options` in the mailer action. ```ruby -class UserMailer < ActionMailer::Base +class UserMailer < ApplicationMailer def welcome_email(user, company) @user = user @url = user_url(@user) @@ -532,7 +537,7 @@ option. In such cases don't forget to add the `:content_type` option. Rails will default to `text/plain` otherwise. ```ruby -class UserMailer < ActionMailer::Base +class UserMailer < ApplicationMailer def welcome_email(user, email_body) mail(to: user.email, body: email_body, @@ -562,7 +567,7 @@ mailer, and pass the email object to the mailer `receive` instance method. Here's an example: ```ruby -class UserMailer < ActionMailer::Base +class UserMailer < ApplicationMailer def receive(email) page = Page.find_by(address: email.to.first) page.emails.create( @@ -598,7 +603,7 @@ Action Mailer allows for you to specify a `before_action`, `after_action` and using instance variables set in your mailer action. ```ruby -class UserMailer < ActionMailer::Base +class UserMailer < ApplicationMailer after_action :set_delivery_options, :prevent_delivery_to_guests, :set_business_headers @@ -728,7 +733,9 @@ Mailer framework. You can do this in an initializer file `config/initializers/sandbox_email_interceptor.rb` ```ruby -ActionMailer::Base.register_interceptor(SandboxEmailInterceptor) if Rails.env.staging? +if Rails.env.staging? + ActionMailer::Base.register_interceptor(SandboxEmailInterceptor) +end ``` NOTE: The example above uses a custom environment called "staging" for a diff --git a/guides/source/action_view_overview.md b/guides/source/action_view_overview.md index 683e633668..a6bde4f517 100644 --- a/guides/source/action_view_overview.md +++ b/guides/source/action_view_overview.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + Action View Overview ==================== @@ -7,7 +9,6 @@ After reading this guide, you will know: * How best to use templates, partials, and layouts. * What helpers are provided by Action View and how to make your own. * How to use localized views. -* How to use Action View outside of Rails. -------------------------------------------------------------------------------- diff --git a/guides/source/active_job_basics.md b/guides/source/active_job_basics.md index 0e9e4eff1d..31c9406d5c 100644 --- a/guides/source/active_job_basics.md +++ b/guides/source/active_job_basics.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + Active Job Basics ================= @@ -23,7 +25,7 @@ clean-ups, to billing charges, to mailings. Anything that can be chopped up into small units of work and run in parallel, really. -The Purpose of the Active Job +The Purpose of Active Job ----------------------------- The main point is to ensure that all Rails apps will have a job infrastructure in place, even if it's in the form of an "immediate runner". We can then have @@ -56,9 +58,6 @@ You can also create a job that will run on a specific queue: $ bin/rails generate job guests_cleanup --queue urgent ``` -As you can see, you can generate jobs just like you use other generators with -Rails. - If you don't want to use a generator, you could create your own file inside of `app/jobs`, just make sure that it inherits from `ActiveJob::Base`. @@ -107,14 +106,19 @@ Active Job has built-in adapters for multiple queueing backends (Sidekiq, Resque, Delayed Job and others). To get an up-to-date list of the adapters see the API Documentation for [ActiveJob::QueueAdapters](http://api.rubyonrails.org/classes/ActiveJob/QueueAdapters.html). -### Changing the Backend +### Setting the Backend -You can easily change your queueing backend: +You can easily set your queueing backend: ```ruby -# be sure to have the adapter gem in your Gemfile and follow -# the adapter specific installation and deployment instructions -config.active_job.queue_adapter = :sidekiq +# config/application.rb +module YourApp + class Application < Rails::Application + # Be sure to have the adapter's gem in your Gemfile and follow + # the adapter's specific installation and deployment instructions. + config.active_job.queue_adapter = :sidekiq + end +end ``` @@ -149,11 +153,11 @@ class GuestsCleanupJob < ActiveJob::Base end # Now your job will run on queue production_low_priority on your -# production environment and on beta_low_priority on your beta +# production environment and on staging_low_priority on your staging # environment ``` -The default queue name prefix delimiter is '_'. This can be changed by setting +The default queue name prefix delimiter is '\_'. This can be changed by setting `config.active_job.queue_name_delimiter` in `application.rb`: ```ruby @@ -213,8 +217,8 @@ backends you need to specify the queues to listen to. Callbacks --------- -Active Job provides hooks during the lifecycle of a job. Callbacks allow you to -trigger logic during the lifecycle of a job. +Active Job provides hooks during the life cycle of a job. Callbacks allow you to +trigger logic during the life cycle of a job. ### Available callbacks @@ -301,7 +305,6 @@ Active Job provides a way to catch exceptions raised during the execution of the job: ```ruby - class GuestsCleanupJob < ActiveJob::Base queue_as :default diff --git a/guides/source/active_model_basics.md b/guides/source/active_model_basics.md index a520b91a4d..8dee1cc5ec 100644 --- a/guides/source/active_model_basics.md +++ b/guides/source/active_model_basics.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + Active Model Basics =================== diff --git a/guides/source/active_record_basics.md b/guides/source/active_record_basics.md index bd074d0055..9d2ba328ea 100644 --- a/guides/source/active_record_basics.md +++ b/guides/source/active_record_basics.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + Active Record Basics ==================== @@ -358,7 +360,7 @@ class CreatePublications < ActiveRecord::Migration t.string :publisher_type t.boolean :single_issue - t.timestamps + t.timestamps null: false end add_index :publications, :publication_type_id end diff --git a/guides/source/active_record_callbacks.md b/guides/source/active_record_callbacks.md index 9c7e60cbb0..9d3a8c3af6 100644 --- a/guides/source/active_record_callbacks.md +++ b/guides/source/active_record_callbacks.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + Active Record Callbacks ======================= diff --git a/guides/source/active_record_migrations.md b/guides/source/active_record_migrations.md index c8a31fe7b8..8ae282bad2 100644 --- a/guides/source/active_record_migrations.md +++ b/guides/source/active_record_migrations.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + Active Record Migrations ======================== @@ -39,7 +41,7 @@ class CreateProducts < ActiveRecord::Migration t.string :name t.text :description - t.timestamps + t.timestamps null: false end end end @@ -285,7 +287,7 @@ class CreateProducts < ActiveRecord::Migration t.string :name t.text :description - t.timestamps + t.timestamps null: false end end end @@ -452,6 +454,8 @@ number of digits after the decimal point. are using a dynamic value (such as a date), the default will only be calculated the first time (i.e. on the date the migration is applied). * `index` Adds an index for the column. +* `required` Adds `required: true` for `belongs_to` associations and +`null: false` to the column in the migration. Some adapters may support additional options; see the adapter specific API docs for further information. @@ -824,7 +828,7 @@ class CreateProducts < ActiveRecord::Migration create_table :products do |t| t.string :name t.text :description - t.timestamps + t.timestamps null: false end end diff --git a/guides/source/active_record_postgresql.md b/guides/source/active_record_postgresql.md index 6c94218ef6..fa0f31cbbd 100644 --- a/guides/source/active_record_postgresql.md +++ b/guides/source/active_record_postgresql.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + Active Record and PostgreSQL ============================ @@ -83,9 +85,12 @@ Book.where("array_length(ratings, 1) >= 3") * [type definition](http://www.postgresql.org/docs/9.3/static/hstore.html) +NOTE: you need to enable the `hstore` extension to use hstore. + ```ruby # db/migrate/20131009135255_create_profiles.rb ActiveRecord::Schema.define do + enable_extension 'hstore' unless extension_enabled?('hstore') create_table :profiles do |t| t.hstore 'settings' end @@ -103,11 +108,6 @@ profile.settings # => {"color"=>"blue", "resolution"=>"800x600"} profile.settings = {"color" => "yellow", "resolution" => "1280x1024"} profile.save! - -## you need to call _will_change! if you are editing the store in place -profile.settings["color"] = "green" -profile.settings_will_change! -profile.save! ``` ### JSON @@ -219,7 +219,7 @@ Currently there is no special support for enumerated types. They are mapped as normal text columns: ```ruby -# db/migrate/20131220144913_create_events.rb +# db/migrate/20131220144913_create_articles.rb execute <<-SQL CREATE TYPE article_status AS ENUM ('draft', 'published'); SQL @@ -281,7 +281,7 @@ end # Usage User.create settings: "01010011" user = User.first -user.settings # => "(Paris,Champs-Élysées)" +user.settings # => "01010011" user.settings = "0xAF" user.settings # => 10101111 user.save! diff --git a/guides/source/active_record_querying.md b/guides/source/active_record_querying.md index e1a465c64f..f8c64cbd0c 100644 --- a/guides/source/active_record_querying.md +++ b/guides/source/active_record_querying.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + Active Record Query Interface ============================= @@ -9,6 +11,7 @@ After reading this guide, you will know: * How to specify the order, retrieved attributes, grouping, and other properties of the found records. * How to use eager loading to reduce the number of database queries needed for data retrieval. * How to use dynamic finders methods. +* How to use method chaining to use multiple ActiveRecord methods together. * How to check for the existence of particular records. * How to perform various calculations on Active Record models. * How to run EXPLAIN on relations. @@ -87,7 +90,7 @@ The primary operation of `Model.find(options)` can be summarized as: * Convert the supplied options to an equivalent SQL query. * Fire the SQL query and retrieve the corresponding results from the database. * Instantiate the equivalent Ruby object of the appropriate model for every resulting row. -* Run `after_find` callbacks, if any. +* Run `after_find` and then `after_initialize` callbacks, if any. ### Retrieving a Single Object @@ -1327,14 +1330,66 @@ You can specify an exclamation point (`!`) on the end of the dynamic finders to If you want to find both by name and locked, you can chain these finders together by simply typing "`and`" between the fields. For example, `Client.find_by_first_name_and_locked("Ryan", true)`. +Understanding The Method Chaining +--------------------------------- + +The Active Record pattern implements [Method Chaining](http://en.wikipedia.org/wiki/Method_chaining), +which allow us to use multiple Active Record methods together in a simple and straightforward way. + +You can chain methods in a statement when the previous method called returns an +`ActiveRecord::Relation`, like `all`, `where`, and `joins`. Methods that return +a single object (see [Retrieving a Single Object Section](#retrieving-a-single-object)) +have to be at the end of the statement. + +There are some examples below. This guide won't cover all the possibilities, just a few as examples. +When an Active Record method is called, the query is not immediately generated and sent to the database, +this just happens when the data is actually needed. So each example below generates a single query. + +### Retrieving filtered data from multiple tables + +```ruby +Person + .select('people.id, people.name, comments.text') + .joins(:comments) + .where('comments.created_at > ?', 1.week.ago) +``` + +The result should be something like this: + +```sql +SELECT people.id, people.name, comments.text +FROM people +INNER JOIN comments + ON comments.person_id = people.id +WHERE comments.created_at = '2015-01-01' +``` + +### Retrieving specific data from multiple tables + +```ruby +Person + .select('people.id, people.name, companies.name') + .joins(:company) + .find_by('people.name' => 'John') # this should be the last +``` + +The above should generate: + +```sql +SELECT people.id, people.name, companies.name +FROM people +INNER JOIN companies + ON companies.person_id = people.id +WHERE people.name = 'John' +LIMIT 1 +``` + +NOTE: Remember that, if `find_by` returns more than one registry, it will take +just the first and ignore the others. Note the `LIMIT 1` statement above. + Find or Build a New Object -------------------------- -NOTE: Some dynamic finders have been deprecated in Rails 4.0 and will be -removed in Rails 4.1. The best practice is to use Active Record scopes -instead. You can find the deprecation gem at -https://github.com/rails/activerecord-deprecated_finders - It's common that you need to find a record or create it if it doesn't exist. You can do that with the `find_or_create_by` and `find_or_create_by!` methods. ### `find_or_create_by` diff --git a/guides/source/active_record_validations.md b/guides/source/active_record_validations.md index 546c0608ee..8c832bafff 100644 --- a/guides/source/active_record_validations.md +++ b/guides/source/active_record_validations.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + Active Record Validations ========================= @@ -487,6 +489,8 @@ constraints to acceptable values: * `:even` - Specifies the value must be an even number if set to true. The default error message for this option is _"must be even"_. +NOTE: By default, `numericality` doesn't allow `nil` values. You can use `allow_nil: true` option to permit it. + The default error message is _"is not a number"_. ### `presence` diff --git a/guides/source/active_support_core_extensions.md b/guides/source/active_support_core_extensions.md index 616b813817..ba839e1723 100644 --- a/guides/source/active_support_core_extensions.md +++ b/guides/source/active_support_core_extensions.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + Active Support Core Extensions ============================== @@ -1447,7 +1449,7 @@ Returns the substring of the string starting at position `position`: "hello".from(0) # => "hello" "hello".from(2) # => "llo" "hello".from(-2) # => "lo" -"hello".from(10) # => "" if < 1.9, nil in 1.9 +"hello".from(10) # => nil ``` NOTE: Defined in `active_support/core_ext/string/access.rb`. @@ -1950,24 +1952,6 @@ as well as adding or subtracting their results from a Time object. For example: (4.months + 5.years).from_now ``` -While these methods provide precise calculation when used as in the examples above, care -should be taken to note that this is not true if the result of `months', `years', etc is -converted before use: - -```ruby -# equivalent to 30.days.to_i.from_now -1.month.to_i.from_now - -# equivalent to 365.25.days.to_f.from_now -1.year.to_f.from_now -``` - -In such cases, Ruby's core [Date](http://ruby-doc.org/stdlib/libdoc/date/rdoc/Date.html) and -[Time](http://ruby-doc.org/stdlib/libdoc/time/rdoc/Time.html) should be used for precision -date and time arithmetic. - -NOTE: Defined in `active_support/core_ext/numeric/time.rb`. - ### Formatting Enables the formatting of numbers in a variety of ways. @@ -3889,7 +3873,7 @@ def default_helper_module! module_name = name.sub(/Controller$/, '') module_path = module_name.underscore helper module_path -rescue MissingSourceFile => e +rescue LoadError => e raise e unless e.is_missing? "helpers/#{module_path}_helper" rescue NameError => e raise e unless e.missing_name? "#{module_name}Helper" @@ -3901,7 +3885,7 @@ NOTE: Defined in `active_support/core_ext/name_error.rb`. Extensions to `LoadError` ------------------------- -Active Support adds `is_missing?` to `LoadError`, and also assigns that class to the constant `MissingSourceFile` for backwards compatibility. +Active Support adds `is_missing?` to `LoadError`. Given a path name `is_missing?` tests whether the exception was raised due to that particular file (except perhaps for the ".rb" extension). @@ -3912,7 +3896,7 @@ def default_helper_module! module_name = name.sub(/Controller$/, '') module_path = module_name.underscore helper module_path -rescue MissingSourceFile => e +rescue LoadError => e raise e unless e.is_missing? "helpers/#{module_path}_helper" rescue NameError => e raise e unless e.missing_name? "#{module_name}Helper" diff --git a/guides/source/active_support_instrumentation.md b/guides/source/active_support_instrumentation.md index 9dfacce560..0aa74e387d 100644 --- a/guides/source/active_support_instrumentation.md +++ b/guides/source/active_support_instrumentation.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + Active Support Instrumentation ============================== diff --git a/guides/source/api_documentation_guidelines.md b/guides/source/api_documentation_guidelines.md index a2ebf55335..d481700709 100644 --- a/guides/source/api_documentation_guidelines.md +++ b/guides/source/api_documentation_guidelines.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + API Documentation Guidelines ============================ diff --git a/guides/source/asset_pipeline.md b/guides/source/asset_pipeline.md index ae0f19c02a..64d1c31083 100644 --- a/guides/source/asset_pipeline.md +++ b/guides/source/asset_pipeline.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + The Asset Pipeline ================== @@ -167,9 +169,8 @@ directory. Files in this directory are served by the Sprockets middleware. Assets can still be placed in the `public` hierarchy. Any assets under `public` will be served as static files by the application or web server when -`config.serve_static_assets` is set to true. You should use -`app/assets` for files that must undergo some pre-processing before they are -served. +`config.serve_static_files` is set to true. You should use `app/assets` for +files that must undergo some pre-processing before they are served. In production, Rails precompiles these files to `public/assets` by default. The precompiled copies are then served as static assets by the web server. The files @@ -181,12 +182,12 @@ When you generate a scaffold or a controller, Rails also generates a JavaScript file (or CoffeeScript file if the `coffee-rails` gem is in the `Gemfile`) and a Cascading Style Sheet file (or SCSS file if `sass-rails` is in the `Gemfile`) for that controller. Additionally, when generating a scaffold, Rails generates -the file scaffolds.css (or scaffolds.css.scss if `sass-rails` is in the +the file scaffolds.css (or scaffolds.scss if `sass-rails` is in the `Gemfile`.) For example, if you generate a `ProjectsController`, Rails will also add a new -file at `app/assets/javascripts/projects.js.coffee` and another at -`app/assets/stylesheets/projects.css.scss`. By default these files will be ready +file at `app/assets/javascripts/projects.coffee` and another at +`app/assets/stylesheets/projects.scss`. By default these files will be ready to use by your application immediately using the `require_tree` directive. See [Manifest Files and Directives](#manifest-files-and-directives) for more details on require_tree. @@ -231,7 +232,9 @@ images, JavaScript files or stylesheets. scope of the application or those libraries which are shared across applications. * `vendor/assets` is for assets that are owned by outside entities, such as -code for JavaScript plugins and CSS frameworks. +code for JavaScript plugins and CSS frameworks. Keep in mind that third party +code with references to other files also processed by the asset Pipeline (images, +stylesheets, etc.), will need to be rewritten to use helpers like `asset_path`. WARNING: If you are upgrading from Rails 3, please take into account that assets under `lib/assets` or `vendor/assets` are available for inclusion via the @@ -421,7 +424,7 @@ $('#logo').attr({ src: "<%= asset_path('logo.png') %>" }); This writes the path to the particular asset being referenced. Similarly, you can use the `asset_path` helper in CoffeeScript files with `erb` -extension (e.g., `application.js.coffee.erb`): +extension (e.g., `application.coffee.erb`): ```js $('#logo').attr src: "<%= asset_path('logo.png') %>" @@ -522,8 +525,8 @@ The file extensions used on an asset determine what preprocessing is applied. When a controller or a scaffold is generated with the default Rails gemset, a CoffeeScript file and a SCSS file are generated in place of a regular JavaScript and CSS file. The example used before was a controller called "projects", which -generated an `app/assets/javascripts/projects.js.coffee` and an -`app/assets/stylesheets/projects.css.scss` file. +generated an `app/assets/javascripts/projects.coffee` and an +`app/assets/stylesheets/projects.scss` file. In development mode, or if the asset pipeline is disabled, when these files are requested they are processed by the processors provided by the `coffee-script` @@ -535,13 +538,13 @@ web server. Additional layers of preprocessing can be requested by adding other extensions, where each extension is processed in a right-to-left manner. These should be used in the order the processing should be applied. For example, a stylesheet -called `app/assets/stylesheets/projects.css.scss.erb` is first processed as ERB, +called `app/assets/stylesheets/projects.scss.erb` is first processed as ERB, then SCSS, and finally served as CSS. The same applies to a JavaScript file - -`app/assets/javascripts/projects.js.coffee.erb` is processed as ERB, then +`app/assets/javascripts/projects.coffee.erb` is processed as ERB, then CoffeeScript, and served as JavaScript. Keep in mind the order of these preprocessors is important. For example, if -you called your JavaScript file `app/assets/javascripts/projects.js.erb.coffee` +you called your JavaScript file `app/assets/javascripts/projects.erb.coffee` then it would be processed with the CoffeeScript interpreter first, which wouldn't understand ERB and therefore you would run into problems. diff --git a/guides/source/association_basics.md b/guides/source/association_basics.md index 61490ceb54..95c7e747ef 100644 --- a/guides/source/association_basics.md +++ b/guides/source/association_basics.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + Active Record Associations ========================== @@ -101,13 +103,13 @@ class CreateOrders < ActiveRecord::Migration def change create_table :customers do |t| t.string :name - t.timestamps + t.timestamps null: false end create_table :orders do |t| t.belongs_to :customer, index: true t.datetime :order_date - t.timestamps + t.timestamps null: false end end end @@ -132,13 +134,13 @@ class CreateSuppliers < ActiveRecord::Migration def change create_table :suppliers do |t| t.string :name - t.timestamps + t.timestamps null: false end create_table :accounts do |t| t.belongs_to :supplier, index: true t.string :account_number - t.timestamps + t.timestamps null: false end end end @@ -165,13 +167,13 @@ class CreateCustomers < ActiveRecord::Migration def change create_table :customers do |t| t.string :name - t.timestamps + t.timestamps null: false end create_table :orders do |t| t.belongs_to :customer, index:true t.datetime :order_date - t.timestamps + t.timestamps null: false end end end @@ -207,19 +209,19 @@ class CreateAppointments < ActiveRecord::Migration def change create_table :physicians do |t| t.string :name - t.timestamps + t.timestamps null: false end create_table :patients do |t| t.string :name - t.timestamps + t.timestamps null: false end create_table :appointments do |t| t.belongs_to :physician, index: true t.belongs_to :patient, index: true t.datetime :appointment_date - t.timestamps + t.timestamps null: false end end end @@ -291,19 +293,19 @@ class CreateAccountHistories < ActiveRecord::Migration def change create_table :suppliers do |t| t.string :name - t.timestamps + t.timestamps null: false end create_table :accounts do |t| t.belongs_to :supplier, index: true t.string :account_number - t.timestamps + t.timestamps null: false end create_table :account_histories do |t| t.belongs_to :account, index: true t.integer :credit_rating - t.timestamps + t.timestamps null: false end end end @@ -332,12 +334,12 @@ class CreateAssembliesAndParts < ActiveRecord::Migration def change create_table :assemblies do |t| t.string :name - t.timestamps + t.timestamps null: false end create_table :parts do |t| t.string :part_number - t.timestamps + t.timestamps null: false end create_table :assemblies_parts, id: false do |t| @@ -371,13 +373,13 @@ class CreateSuppliers < ActiveRecord::Migration def change create_table :suppliers do |t| t.string :name - t.timestamps + t.timestamps null: false end create_table :accounts do |t| t.integer :supplier_id t.string :account_number - t.timestamps + t.timestamps null: false end add_index :accounts, :supplier_id @@ -455,7 +457,7 @@ class CreatePictures < ActiveRecord::Migration t.string :name t.integer :imageable_id t.string :imageable_type - t.timestamps + t.timestamps null: false end add_index :pictures, :imageable_id @@ -471,7 +473,7 @@ class CreatePictures < ActiveRecord::Migration create_table :pictures do |t| t.string :name t.references :imageable, polymorphic: true, index: true - t.timestamps + t.timestamps null: false end end end @@ -501,7 +503,7 @@ class CreateEmployees < ActiveRecord::Migration def change create_table :employees do |t| t.references :manager, index: true - t.timestamps + t.timestamps null: false end end end @@ -879,10 +881,12 @@ class Order < ActiveRecord::Base belongs_to :customer, counter_cache: :count_of_orders end class Customer < ActiveRecord::Base - has_many :orders + has_many :orders, counter_cache: :count_of_orders end ``` +NOTE: You only need to specify the :counter_cache option on the "has_many side" of the association when using a custom name for the counter cache. + Counter cache columns are added to the containing model's list of read-only attributes through `attr_readonly`. ##### `:dependent` @@ -1495,6 +1499,7 @@ The `has_many` association supports these options: * `:as` * `:autosave` * `:class_name` +* `:counter_cache` * `:dependent` * `:foreign_key` * `:inverse_of` @@ -1522,6 +1527,10 @@ class Customer < ActiveRecord::Base end ``` +##### `:counter_cache` + +This option can be used to configure a custom named `:counter_cache`. You only need this option when you customized the name of your `:counter_cache` on the [belongs_to association](#options-for-belongs-to). + ##### `:dependent` Controls what happens to the associated objects when their owner is destroyed: @@ -1532,8 +1541,6 @@ Controls what happens to the associated objects when their owner is destroyed: * `:restrict_with_exception` causes an exception to be raised if there are any associated records * `:restrict_with_error` causes an error to be added to the owner if there are any associated objects -NOTE: This option is ignored when you use the `:through` option on the association. - ##### `:foreign_key` By convention, Rails assumes that the column used to hold the foreign key on the other model is the name of this model with the suffix `_id` added. The `:foreign_key` option lets you set the name of the foreign key directly: diff --git a/guides/source/autoloading_and_reloading_constants.md b/guides/source/autoloading_and_reloading_constants.md new file mode 100644 index 0000000000..489ea681e2 --- /dev/null +++ b/guides/source/autoloading_and_reloading_constants.md @@ -0,0 +1,1300 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + +Autoloading and Reloading Constants +=================================== + +This guide documents how constant autoloading and reloading works. + +After reading this guide, you will know: + +* Key aspects of Ruby constants +* What is `autoload_paths` +* How constant autoloading works +* What is `require_dependency` +* How constant reloading works +* Solutions to common autoloading gotchas + +-------------------------------------------------------------------------------- + + +Introduction +------------ + +Ruby on Rails allows applications to be written as if their code was preloaded. + +In a normal Ruby program classes need to load their dependencies: + +```ruby +require 'application_controller' +require 'post' + +class PostsController < ApplicationController + def index + @posts = Post.all + end +end +``` + +Our Rubyist instinct quickly sees some redundancy in there: If classes were +defined in files matching their name, couldn't their loading be automated +somehow? We could save scanning the file for dependencies, which is brittle. + +Moreover, `Kernel#require` loads files once, but development is much more smooth +if code gets refreshed when it changes without restarting the server. It would +be nice to be able to use `Kernel#load` in development, and `Kernel#require` in +production. + +Indeed, those features are provided by Ruby on Rails, where we just write + +```ruby +class PostsController < ApplicationController + def index + @posts = Post.all + end +end +``` + +This guide documents how that works. + + +Constants Refresher +------------------- + +While constants are trivial in most programming languages, they are a rich +topic in Ruby. + +It is beyond the scope of this guide to document Ruby constants, but we are +nevertheless going to highlight a few key topics. Truly grasping the following +sections is instrumental to understanding constant autoloading and reloading. + +### Nesting + +Class and module definitions can be nested to create namespaces: + +```ruby +module XML + class SAXParser + # (1) + end +end +``` + +The *nesting* at any given place is the collection of enclosing nested class and +module objects outwards. For example, in the previous example, the nesting at +(1) is + +```ruby +[XML::SAXParser, XML] +``` + +It is important to understand that the nesting is composed of class and module +*objects*, it has nothing to do with the constants used to access them, and is +also unrelated to their names. + +For instance, while this definition is similar to the previous one: + +```ruby +class XML::SAXParser + # (2) +end +``` + +the nesting in (2) is different: + +```ruby +[XML::SAXParser] +``` + +`XML` does not belong to it. + +We can see in this example that the name of a class or module that belongs to a +certain nesting does not necessarily correlate with the namespaces at the spot. + +Even more, they are totally independent, take for instance + +```ruby +module X::Y + module A::B + # (3) + end +end +``` + +The nesting in (3) consists of two module objects: + +```ruby +[A::B, X::Y] +``` + +So, it not only doesn't end in `A`, which does not even belong to the nesting, +but it also contains `X::Y`, which is independent from `A::B`. + +The nesting is an internal stack maintained by the interpreter, and it gets +modified according to these rules: + +* The class object following a `class` keyword gets pushed when its body is +executed, and popped after it. + +* The module object following a `module` keyword gets pushed when its body is +executed, and popped after it. + +* A singleton class opened with `class << object` gets pushed, and popped later. + +* When any of the `*_eval` family of methods is called using a string argument, +the singleton class of the receiver is pushed to the nesting of the eval'ed +code. + +* The nesting at the top-level of code interpreted by `Kernel#load` is empty +unless the `load` call receives a true value as second argument, in which case +a newly created anonymous module is pushed by Ruby. + +It is interesting to observe that blocks do not modify the stack. In particular +the blocks that may be passed to `Class.new` and `Module.new` do not get the +class or module being defined pushed to their nesting. That's one of the +differences between defining classes and modules in one way or another. + +The nesting at any given place can be inspected with `Module.nesting`. + +### Class and Module Definitions are Constant Assignments + +Let's suppose the following snippet creates a class (rather than reopening it): + +```ruby +class C +end +``` + +Ruby creates a constant `C` in `Object` and stores in that constant a class +object. The name of the class instance is "C", a string, named after the +constant. + +That is, + +```ruby +class Project < ActiveRecord::Base +end +``` + +performs a constant assignment equivalent to + +```ruby +Project = Class.new(ActiveRecord::Base) +``` + +including setting the name of the class as a side-effect: + +```ruby +Project.name # => "Project" +``` + +Constant assignment has a special rule to make that happen: if the object +being assigned is an anonymous class or module, Ruby sets the object's name to +the name of the constant. + +INFO. From then on, what happens to the constant and the instance does not +matter. For example, the constant could be deleted, the class object could be +assigned to a different constant, be stored in no constant anymore, etc. Once +the name is set, it doesn't change. + +Similarly, module creation using the `module` keyword as in + +```ruby +module Admin +end +``` + +performs a constant assignment equivalent to + +```ruby +Admin = Module.new +``` + +including setting the name as a side-effect: + +```ruby +Admin.name # => "Admin" +``` + +WARNING. The execution context of a block passed to `Class.new` or `Module.new` +is not entirely equivalent to the one of the body of the definitions using the +`class` and `module` keywords. But both idioms result in the same constant +assignment. + +Thus, when one informally says "the `String` class", that really means: the +class object stored in the constant called "String" in the class object stored +in the `Object` constant. `String` is otherwise an ordinary Ruby constant and +everything related to constants such as resolution algorithms applies to it. + +Likewise, in the controller + +```ruby +class PostsController < ApplicationController + def index + @posts = Post.all + end +end +``` + +`Post` is not syntax for a class. Rather, `Post` is a regular Ruby constant. If +all is good, the constant evaluates to an object that responds to `all`. + +That is why we talk about *constant* autoloading, Rails has the ability to +load constants on the fly. + +### Constants are Stored in Modules + +Constants belong to modules in a very literal sense. Classes and modules have +a constant table; think of it as a hash table. + +Let's analyze an example to really understand what that means. While common +abuses of language like "the `String` class" are convenient, the exposition is +going to be precise here for didactic purposes. + +Let's consider the following module definition: + +```ruby +module Colors + RED = '0xff0000' +end +``` + +First, when the `module` keyword is processed, the interpreter creates a new +entry in the constant table of the class object stored in the `Object` constant. +Said entry associates the name "Colors" to a newly created module object. +Furthermore, the interpreter sets the name of the new module object to be the +string "Colors". + +Later, when the body of the module definition is interpreted, a new entry is +created in the constant table of the module object stored in the `Colors` +constant. That entry maps the name "RED" to the string "0xff0000". + +In particular, `Colors::RED` is totally unrelated to any other `RED` constant +that may live in any other class or module object. If there were any, they +would have separate entries in their respective constant tables. + +Pay special attention in the previous paragraphs to the distinction between +class and module objects, constant names, and value objects associated to them +in constant tables. + +### Resolution Algorithms + +#### Resolution Algorithm for Relative Constants + +At any given place in the code, let's define *cref* to be the first element of +the nesting if it is not empty, or `Object` otherwise. + +Without getting too much into the details, the resolution algorithm for relative +constant references goes like this: + +1. If the nesting is not empty the constant is looked up in its elements and in +order. The ancestors of those elements are ignored. + +2. If not found, then the algorithm walks up the ancestor chain of the cref. + +3. If not found, `const_missing` is invoked on the cref. The default +implementation of `const_missing` raises `NameError`, but it can be overridden. + +Rails autoloading **does not emulate this algorithm**, but its starting point is +the name of the constant to be autoloaded, and the cref. See more in [Relative +References](#autoloading-algorithms-relative-references). + +#### Resolution Algorithm for Qualified Constants + +Qualified constants look like this: + +```ruby +Billing::Invoice +``` + +`Billing::Invoice` is composed of two constants: `Billing` is relative and is +resolved using the algorithm of the previous section. + +INFO. Leading colons would make the first segment absolute rather than +relative: `::Billing::Invoice`. That would force `Billing` to be looked up +only as a top-level constant. + +`Invoice` on the other hand is qualified by `Billing` and we are going to see +its resolution next. Let's call *parent* to that qualifying class or module +object, that is, `Billing` in the example above. The algorithm for qualified +constants goes like this: + +1. The constant is looked up in the parent and its ancestors. + +2. If the lookup fails, `const_missing` is invoked in the parent. The default +implementation of `const_missing` raises `NameError`, but it can be overridden. + +As you see, this algorithm is simpler than the one for relative constants. In +particular, the nesting plays no role here, and modules are not special-cased, +if neither they nor their ancestors have the constants, `Object` is **not** +checked. + +Rails autoloading **does not emulate this algorithm**, but its starting point is +the name of the constant to be autoloaded, and the parent. See more in +[Qualified References](#qualified-references). + + +Vocabulary +---------- + +### Parent Namespaces + +Given a string with a constant path we define its *parent namespace* to be the +string that results from removing its rightmost segment. + +For example, the parent namespace of the string "A::B::C" is the string "A::B", +the parent namespace of "A::B" is "A", and the parent namespace of "A" is "". + +The interpretation of a parent namespace when thinking about classes and modules +is tricky though. Let's consider a module M named "A::B": + +* The parent namespace, "A", may not reflect nesting at a given spot. + +* The constant `A` may no longer exist, some code could have removed it from +`Object`. + +* If `A` exists, the class or module that was originally in `A` may not be there +anymore. For example, if after a constant removal there was another constant +assignment there would generally be a different object in there. + +* In such case, it could even happen that the reassigned `A` held a new class or +module called also "A"! + +* In the previous scenarios M would no longer be reachable through `A::B` but +the module object itself could still be alive somewhere and its name would +still be "A::B". + +The idea of a parent namespace is at the core of the autoloading algorithms +and helps explain and understand their motivation intuitively, but as you see +that metaphor leaks easily. Given an edge case to reason about, take always into +account that by "parent namespace" the guide means exactly that specific string +derivation. + +### Loading Mechanism + +Rails autoloads files with `Kernel#load` when `config.cache_classes` is false, +the default in development mode, and with `Kernel#require` otherwise, the +default in production mode. + +`Kernel#load` allows Rails to execute files more than once if [constant +reloading](#constant-reloading) is enabled. + +This guide uses the word "load" freely to mean a given file is interpreted, but +the actual mechanism can be `Kernel#load` or `Kernel#require` depending on that +flag. + + +Autoloading Availability +------------------------ + +Rails is always able to autoload provided its environment is in place. For +example the `runner` command autoloads: + +``` +$ bin/rails runner 'p User.column_names' +["id", "email", "created_at", "updated_at"] +``` + +The console autoloads, the test suite autoloads, and of course the application +autoloads. + +By default, Rails eager loads the application files when it boots in production +mode, so most of the autoloading going on in development does not happen. But +autoloading may still be triggered during eager loading. + +For example, given + +```ruby +class BeachHouse < House +end +``` + +if `House` is still unknown when `app/models/beach_house.rb` is being eager +loaded, Rails autoloads it. + + +autoload_paths +-------------- + +As you probably know, when `require` gets a relative file name: + +```ruby +require 'erb' +``` + +Ruby looks for the file in the directories listed in `$LOAD_PATH`. That is, Ruby +iterates over all its directories and for each one of them checks whether they +have a file called "erb.rb", or "erb.so", or "erb.o", or "erb.dll". If it finds +any of them, the interpreter loads it and ends the search. Otherwise, it tries +again in the next directory of the list. If the list gets exhausted, `LoadError` +is raised. + +We are going to cover how constant autoloading works in more detail later, but +the idea is that when a constant like `Post` is hit and missing, if there's a +`post.rb` file for example in `app/models` Rails is going to find it, evaluate +it, and have `Post` defined as a side-effect. + +Alright, Rails has a collection of directories similar to `$LOAD_PATH` in which +to look up `post.rb`. That collection is called `autoload_paths` and by +default it contains: + +* All subdirectories of `app` in the application and engines. For example, + `app/controllers`. They do not need to be the default ones, any custom + directories like `app/workers` belong automatically to `autoload_paths`. + +* Any existing second level directories called `app/*/concerns` in the + application and engines. + +* The directory `test/mailers/previews`. + +Also, this collection is configurable via `config.autoload_paths`. For example, +`lib` was in the list years ago, but no longer is. An application can opt-in +by adding this to `config/application.rb`: + +```ruby +config.autoload_paths += "#{Rails.root}/lib" +``` + +The value of `autoload_paths` can be inspected. In a just generated application +it is (edited): + +``` +$ bin/rails r 'puts ActiveSupport::Dependencies.autoload_paths' +.../app/assets +.../app/controllers +.../app/helpers +.../app/mailers +.../app/models +.../app/controllers/concerns +.../app/models/concerns +.../test/mailers/previews +``` + +INFO. `autoload_paths` is computed and cached during the initialization process. +The application needs to be restarted to reflect any changes in the directory +structure. + + +Autoloading Algorithms +---------------------- + +### Relative References + +A relative constant reference may appear in several places, for example, in + +```ruby +class PostsController < ApplicationController + def index + @posts = Post.all + end +end +``` + +all three constant references are relative. + +#### Constants after the `class` and `module` Keywords + +Ruby performs a lookup for the constant that follows a `class` or `module` +keyword because it needs to know if the class or module is going to be created +or reopened. + +If the constant is not defined at that point it is not considered to be a +missing constant, autoloading is **not** triggered. + +So, in the previous example, if `PostsController` is not defined when the file +is interpreted Rails autoloading is not going to be triggered, Ruby will just +define the controller. + +#### Top-Level Constants + +On the contrary, if `ApplicationController` is unknown, the constant is +considered missing and an autoload is going to be attempted by Rails. + +In order to load `ApplicationController`, Rails iterates over `autoload_paths`. +First checks if `app/assets/application_controller.rb` exists. If it does not, +which is normally the case, it continues and finds +`app/controllers/application_controller.rb`. + +If the file defines the constant `ApplicationController` all is fine, otherwise +`LoadError` is raised: + +``` +unable to autoload constant ApplicationController, expected +<full path to application_controller.rb> to define it (LoadError) +``` + +INFO. Rails does not require the value of autoloaded constants to be a class or +module object. For example, if the file `app/models/max_clients.rb` defines +`MAX_CLIENTS = 100` autoloading `MAX_CLIENTS` works just fine. + +#### Namespaces + +Autoloading `ApplicationController` looks directly under the directories of +`autoload_paths` because the nesting in that spot is empty. The situation of +`Post` is different, the nesting in that line is `[PostsController]` and support +for namespaces comes into play. + +The basic idea is that given + +```ruby +module Admin + class BaseController < ApplicationController + @@all_roles = Role.all + end +end +``` + +to autoload `Role` we are going to check if it is defined in the current or +parent namespaces, one at a time. So, conceptually we want to try to autoload +any of + +``` +Admin::BaseController::Role +Admin::Role +Role +``` + +in that order. That's the idea. To do so, Rails looks in `autoload_paths` +respectively for file names like these: + +``` +admin/base_controller/role.rb +admin/role.rb +role.rb +``` + +modulus some additional directory lookups we are going to cover soon. + +INFO. `'Constant::Name'.underscore` gives the relative path without extension of +the file name where `Constant::Name` is expected to be defined. + +Let's see how Rails autoloads the `Post` constant in the `PostsController` +above assuming the application has a `Post` model defined in +`app/models/post.rb`. + +First it checks for `posts_controller/post.rb` in `autoload_paths`: + +``` +app/assets/posts_controller/post.rb +app/controllers/posts_controller/post.rb +app/helpers/posts_controller/post.rb +... +test/mailers/previews/posts_controller/post.rb +``` + +Since the lookup is exhausted without success, a similar search for a directory +is performed, we are going to see why in the [next section](#automatic-modules): + +``` +app/assets/posts_controller/post +app/controllers/posts_controller/post +app/helpers/posts_controller/post +... +test/mailers/previews/posts_controller/post +``` + +If all those attempts fail, then Rails starts the lookup again in the parent +namespace. In this case only the top-level remains: + +``` +app/assets/post.rb +app/controllers/post.rb +app/helpers/post.rb +app/mailers/post.rb +app/models/post.rb +``` + +A matching file is found in `app/models/post.rb`. The lookup stops there and the +file is loaded. If the file actually defines `Post` all is fine, otherwise +`LoadError` is raised. + +### Qualified References + +When a qualified constant is missing Rails does not look for it in the parent +namespaces. But there is a caveat: When a constant is missing, Rails is +unable to tell if the trigger was a relative reference or a qualified one. + +For example, consider + +```ruby +module Admin + User +end +``` + +and + +```ruby +Admin::User +``` + +If `User` is missing, in either case all Rails knows is that a constant called +"User" was missing in a module called "Admin". + +If there is a top-level `User` Ruby would resolve it in the former example, but +wouldn't in the latter. In general, Rails does not emulate the Ruby constant +resolution algorithms, but in this case it tries using the following heuristic: + +> If none of the parent namespaces of the class or module has the missing +> constant then Rails assumes the reference is relative. Otherwise qualified. + +For example, if this code triggers autoloading + +```ruby +Admin::User +``` + +and the `User` constant is already present in `Object`, it is not possible that +the situation is + +```ruby +module Admin + User +end +``` + +because otherwise Ruby would have resolved `User` and no autoloading would have +been triggered in the first place. Thus, Rails assumes a qualified reference and +considers the file `admin/user.rb` and directory `admin/user` to be the only +valid options. + +In practice, this works quite well as long as the nesting matches all parent +namespaces respectively and the constants that make the rule apply are known at +that time. + +However, autoloading happens on demand. If by chance the top-level `User` was +not yet loaded, then Rails assumes a relative reference by contract. + +Naming conflicts of this kind are rare in practice, but if one occurs, +`require_dependency` provides a solution by ensuring that the constant needed +to trigger the heuristic is defined in the conflicting place. + +### Automatic Modules + +When a module acts as a namespace, Rails does not require the application to +defines a file for it, a directory matching the namespace is enough. + +Suppose an application has a back office whose controllers are stored in +`app/controllers/admin`. If the `Admin` module is not yet loaded when +`Admin::UsersController` is hit, Rails needs first to autoload the constant +`Admin`. + +If `autoload_paths` has a file called `admin.rb` Rails is going to load that +one, but if there's no such file and a directory called `admin` is found, Rails +creates an empty module and assigns it to the `Admin` constant on the fly. + +### Generic Procedure + +Relative references are reported to be missing in the cref where they were hit, +and qualified references are reported to be missing in their parent. (See +[Resolution Algorithm for Relative +Constants](#resolution-algorithm-for-relative-constants) at the beginning of +this guide for the definition of *cref*, and [Resolution Algorithm for Qualified +Constants](#resolution-algorithm-for-qualified-constants) for the definition of +*parent*.) + +The procedure to autoload constant `C` in an arbitrary situation is as follows: + +``` +if the class or module in which C is missing is Object + let ns = '' +else + let M = the class or module in which C is missing + + if M is anonymous + let ns = '' + else + let ns = M.name + end +end + +loop do + # Look for a regular file. + for dir in autoload_paths + if the file "#{dir}/#{ns.underscore}/c.rb" exists + load/require "#{dir}/#{ns.underscore}/c.rb" + + if C is now defined + return + else + raise LoadError + end + end + end + + # Look for an automatic module. + for dir in autoload_paths + if the directory "#{dir}/#{ns.underscore}/c" exists + if ns is an empty string + let C = Module.new in Object and return + else + let C = Module.new in ns.constantize and return + end + end + end + + if ns is empty + # We reached the top-level without finding the constant. + raise NameError + else + if C exists in any of the parent namespaces + # Qualified constants heuristic. + raise NameError + else + # Try again in the parent namespace. + let ns = the parent namespace of ns and retry + end + end +end +``` + + +require_dependency +------------------ + +Constant autoloading is triggered on demand and therefore code that uses a +certain constant may have it already defined or may trigger an autoload. That +depends on the execution path and it may vary between runs. + +There are times, however, in which you want to make sure a certain constant is +known when the execution reaches some code. `require_dependency` provides a way +to load a file using the current [loading mechanism](#loading-mechanism), and +keeping track of constants defined in that file as if they were autoloaded to +have them reloaded as needed. + +`require_dependency` is rarely needed, but see a couple of use-cases in +[Autoloading and STI](#autoloading-and-sti) and [When Constants aren't +Triggered](#when-constants-aren-t-missed). + +WARNING. Unlike autoloading, `require_dependency` does not expect the file to +define any particular constant. Exploiting this behavior would be a bad practice +though, file and constant paths should match. + + +Constant Reloading +------------------ + +When `config.cache_classes` is false Rails is able to reload autoloaded +constants. + +For example, in you're in a console session and edit some file behind the +scenes, the code can be reloaded with the `reload!` command: + +``` +> reload! +``` + +When the application runs, code is reloaded when something relevant to this +logic changes. In order to do that, Rails monitors a number of things: + +* `config/routes.rb`. + +* Locales. + +* Ruby files under `autoload_paths`. + +* `db/schema.rb` and `db/structure.sql`. + +If anything in there changes, there is a middleware that detects it and reloads +the code. + +Autoloading keeps track of autoloaded constants. Reloading is implemented by +removing them all from their respective classes and modules using +`Module#remove_const`. That way, when the code goes on, those constants are +going to be unknown again, and files reloaded on demand. + +INFO. This is an all-or-nothing operation, Rails does not attempt to reload only +what changed since dependencies between classes makes that really tricky. +Instead, everything is wiped. + + +Module#autoload isn't Involved +------------------------------ + +`Module#autoload` provides a lazy way to load constants that is fully integrated +with the Ruby constant lookup algorithms, dynamic constant API, etc. It is quite +transparent. + +Rails internals make extensive use of it to defer as much work as possible from +the boot process. But constant autoloading in Rails is **not** implemented with +`Module#autoload`. + +One possible implementation based on `Module#autoload` would be to walk the +application tree and issue `autoload` calls that map existing file names to +their conventional constant name. + +There are a number of reasons that prevent Rails from using that implementation. + +For example, `Module#autoload` is only capable of loading files using `require`, +so reloading would not be possible. Not only that, it uses an internal `require` +which is not `Kernel#require`. + +Then, it provides no way to remove declarations in case a file is deleted. If a +constant gets removed with `Module#remove_const` its `autoload` is not triggered +again. Also, it doesn't support qualified names, so files with namespaces should +be interpreted during the walk tree to install their own `autoload` calls, but +those files could have constant references not yet configured. + +An implementation based on `Module#autoload` would be awesome but, as you see, +at least as of today it is not possible. Constant autoloading in Rails is +implemented with `Module#const_missing`, and that's why it has its own contract, +documented in this guide. + + +Common Gotchas +-------------- + +### Nesting and Qualified Constants + +Let's consider + +```ruby +module Admin + class UsersController < ApplicationController + def index + @users = User.all + end + end +end +``` + +and + +```ruby +class Admin::UsersController < ApplicationController + def index + @users = User.all + end +end +``` + +To resolve `User` Ruby checks `Admin` in the former case, but it does not in +the latter because it does not belong to the nesting. (See [Nesting](#nesting) +and [Resolution Algorithms](#resolution-algorithms).) + +Unfortunately Rails autoloading does not know the nesting in the spot where the +constant was missing and so it is not able to act as Ruby would. In particular, +`Admin::User` will get autoloaded in either case. + +Albeit qualified constants with `class` and `module` keywords may technically +work with autoloading in some cases, it is preferable to use relative constants +instead: + +```ruby +module Admin + class UsersController < ApplicationController + def index + @users = User.all + end + end +end +``` + +### Autoloading and STI + +Single Table Inheritance (STI) is a feature of Active Record that enables +storing a hierarchy of models in one single table. The API of such models is +aware of the hierarchy and encapsulates some common needs. For example, given +these classes: + +```ruby +# app/models/polygon.rb +class Polygon < ActiveRecord::Base +end + +# app/models/triangle.rb +class Triangle < Polygon +end + +# app/models/rectangle.rb +class Rectangle < Polygon +end +``` + +`Triangle.create` creates a row that represents a triangle, and +`Rectangle.create` creates a row that represents a rectangle. If `id` is the +ID of an existing record, `Polygon.find(id)` returns an object of the correct +type. + +Methods that operate on collections are also aware of the hierarchy. For +example, `Polygon.all` returns all the records of the table, because all +rectangles and triangles are polygons. Active Record takes care of returning +instances of their corresponding class in the result set. + +Types are autoloaded as needed. For example, if `Polygon.first` is a rectangle +and `Rectangle` has not yet been loaded, Active Record autoloads it and the +record is correctly instantiated. + +All good, but if instead of performing queries based on the root class we need +to work on some subclass, things get interesting. + +While working with `Polygon` you do not need to be aware of all its descendants, +because anything in the table is by definition a polygon, but when working with +subclasses Active Record needs to be able to enumerate the types it is looking +for. Let’s see an example. + +`Rectangle.all` only loads rectangles by adding a type constraint to the query: + +```sql +SELECT "polygons".* FROM "polygons" +WHERE "polygons"."type" IN ("Rectangle") +``` + +Let’s introduce now a subclass of `Rectangle`: + +```ruby +# app/models/square.rb +class Square < Rectangle +end +``` + +`Rectangle.all` should now return rectangles **and** squares: + +```sql +SELECT "polygons".* FROM "polygons" +WHERE "polygons"."type" IN ("Rectangle", "Square") +``` + +But there’s a caveat here: How does Active Record know that the class `Square` +exists at all? + +Even if the file `app/models/square.rb` exists and defines the `Square` class, +if no code yet used that class, `Rectangle.all` issues the query + +```sql +SELECT "polygons".* FROM "polygons" +WHERE "polygons"."type" IN ("Rectangle") +``` + +That is not a bug, the query includes all *known* descendants of `Rectangle`. + +A way to ensure this works correctly regardless of the order of execution is to +load the leaves of the tree by hand at the bottom of the file that defines the +root class: + +```ruby +# app/models/polygon.rb +class Polygon < ActiveRecord::Base +end +require_dependency ‘square’ +``` + +Only the leaves that are **at least grandchildren** need to be loaded this +way. Direct subclasses do not need to be preloaded. If the hierarchy is +deeper, intermediate classes will be autoloaded recursively from the bottom +because their constant will appear in the class definitions as superclass. + +### Autoloading and `require` + +Files defining constants to be autoloaded should never be `require`d: + +```ruby +require 'user' # DO NOT DO THIS + +class UsersController < ApplicationController + ... +end +``` + +There are two possible gotchas here in development mode: + +1. If `User` is autoloaded before reaching the `require`, `app/models/user.rb` +runs again because `load` does not update `$LOADED_FEATURES`. + +2. If the `require` runs first Rails does not mark `User` as an autoloaded +constant and changes to `app/models/user.rb` aren't reloaded. + +Just follow the flow and use constant autoloading always, never mix +autoloading and `require`. As a last resort, if some file absolutely needs to +load a certain file use `require_dependency` to play nice with constant +autoloading. This option is rarely needed in practice, though. + +Of course, using `require` in autoloaded files to load ordinary 3rd party +libraries is fine, and Rails is able to distinguish their constants, they are +not marked as autoloaded. + +### Autoloading and Initializers + +Consider this assignment in `config/initializers/set_auth_service.rb`: + +```ruby +AUTH_SERVICE = if Rails.env.production? + RealAuthService +else + MockedAuthService +end +``` + +The purpose of this setup would be that the application uses the class that +corresponds to the environment via `AUTH_SERVICE`. In development mode +`MockedAuthService` gets autoloaded when the initializer runs. Let’s suppose +we do some requests, change its implementation, and hit the application again. +To our surprise the changes are not reflected. Why? + +As [we saw earlier](#constant-reloading), Rails removes autoloaded constants, +but `AUTH_SERVICE` stores the original class object. Stale, non-reachable +using the original constant, but perfectly functional. + +The following code summarizes the situation: + +```ruby +class C + def quack + 'quack!' + end +end + +X = C +Object.instance_eval { remove_const(:C) } +X.new.quack # => quack! +X.name # => C +C # => uninitialized constant C (NameError) +``` + +Because of that, it is not a good idea to autoload constants on application +initialization. + +In the case above we could implement a dynamic access point: + +```ruby +# app/models/auth_service.rb +class AuthService + if Rails.env.production? + def self.instance + RealAuthService + end + else + def self.instance + MockedAuthService + end + end +end +``` + +and have the application use `AuthService.instance` instead. `AuthService` +would be loaded on demand and be autoload-friendly. + +### `require_dependency` and Initializers + +As we saw before, `require_dependency` loads files in an autoloading-friendly +way. Normally, though, such a call does not make sense in an initializer. + +One could think about doing some [`require_dependency`](#require-dependency) +calls in an initializer to make sure certain constants are loaded upfront, for +example as an attempt to address the [gotcha with STIs](#autoloading-and-sti). + +Problem is, in development mode [autoloaded constants are wiped](#constant-reloading) +if there is any relevant change in the file system. If that happens then +we are in the very same situation the initializer wanted to avoid! + +Calls to `require_dependency` have to be strategically written in autoloaded +spots. + +### When Constants aren't Missed + +#### Relative References + +Let's consider a flight simulator. The application has a default flight model + +```ruby +# app/models/flight_model.rb +class FlightModel +end +``` + +that can be overridden by each airplane, for instance + +```ruby +# app/models/bell_x1/flight_model.rb +module BellX1 + class FlightModel < FlightModel + end +end + +# app/models/bell_x1/aircraft.rb +module BellX1 + class Aircraft + def initialize + @flight_model = FlightModel.new + end + end +end +``` + +The initializer wants to create a `BellX1::FlightModel` and nesting has +`BellX1`, that looks good. But if the default flight model is loaded and the +one for the Bell-X1 is not, the interpreter is able to resolve the top-level +`FlightModel` and autoloading is thus not triggered for `BellX1::FlightModel`. + +That code depends on the execution path. + +These kind of ambiguities can often be resolved using qualified constants: + +```ruby +module BellX1 + class Plane + def flight_model + @flight_model ||= BellX1::FlightModel.new + end + end +end +``` + +Also, `require_dependency` is a solution: + +```ruby +require_dependency 'bell_x1/flight_model' + +module BellX1 + class Plane + def flight_model + @flight_model ||= FlightModel.new + end + end +end +``` + +#### Qualified References + +Given + +```ruby +# app/models/hotel.rb +class Hotel +end + +# app/models/image.rb +class Image +end + +# app/models/hotel/image.rb +class Hotel + class Image < Image + end +end +``` + +the expression `Hotel::Image` is ambiguous because it depends on the execution +path. + +As [we saw before](#resolution-algorithm-for-qualified-constants), Ruby looks +up the constant in `Hotel` and its ancestors. If `app/models/image.rb` has +been loaded but `app/models/hotel/image.rb` hasn't, Ruby does not find `Image` +in `Hotel`, but it does in `Object`: + +``` +$ bin/rails r 'Image; p Hotel::Image' 2>/dev/null +Image # NOT Hotel::Image! +``` + +The code evaluating `Hotel::Image` needs to make sure +`app/models/hotel/image.rb` has been loaded, possibly with +`require_dependency`. + +In these cases the interpreter issues a warning though: + +``` +warning: toplevel constant Image referenced by Hotel::Image +``` + +This surprising constant resolution can be observed with any qualifying class: + +``` +2.1.5 :001 > String::Array +(irb):1: warning: toplevel constant Array referenced by String::Array + => Array +``` + +WARNING. To find this gotcha the qualifying namespace has to be a class, +`Object` is not an ancestor of modules. + +### Autoloading within Singleton Classes + +Let's suppose we have these class definitions: + +```ruby +# app/models/hotel/services.rb +module Hotel + class Services + end +end + +# app/models/hotel/geo_location.rb +module Hotel + class GeoLocation + class << self + Services + end + end +end +``` + +If `Hotel::Services` is known by the time `app/models/hotel/geo_location.rb` +is being loaded, `Services` is resolved by Ruby because `Hotel` belongs to the +nesting when the singleton class of `Hotel::GeoLocation` is opened. + +But if `Hotel::Services` is not known, Rails is not able to autoload it, the +application raises `NameError`. + +The reason is that autoloading is triggered for the singleton class, which is +anonymous, and as [we saw before](#generic-procedure), Rails only checks the +top-level namespace in that edge case. + +An easy solution to this caveat is to qualify the constant: + +```ruby +module Hotel + class GeoLocation + class << self + Hotel::Services + end + end +end +``` + +### Autoloading in `BasicObject` + +Direct descendants of `BasicObject` do not have `Object` among their ancestors +and cannot resolve top-level constants: + +```ruby +class C < BasicObject + String # NameError: uninitialized constant C::String +end +``` + +When autoloading is involved that plot has a twist. Let's consider: + +```ruby +class C < BasicObject + def user + User # WRONG + end +end +``` + +Since Rails checks the top-level namespace `User` gets autoloaded just fine the +first time the `user` method is invoked. You only get the exception if the +`User` constant is known at that point, in particular in a *second* call to +`user`: + +```ruby +c = C.new +c.user # surprisingly fine, User +c.user # NameError: uninitialized constant C::User +``` + +because it detects that a parent namespace already has the constant (see [Qualified +References](#autoloading-algorithms-qualified-references).) + +As with pure Ruby, within the body of a direct descendant of `BasicObject` use +always absolute constant paths: + +```ruby +class C < BasicObject + ::String # RIGHT + + def user + ::User # RIGHT + end +end +``` diff --git a/guides/source/caching_with_rails.md b/guides/source/caching_with_rails.md index cbcd053950..61b991df61 100644 --- a/guides/source/caching_with_rails.md +++ b/guides/source/caching_with_rails.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + Caching with Rails: An overview =============================== @@ -105,7 +107,7 @@ This method generates a cache key that depends on all products and can be used i <% end %> ``` -If you want to cache a fragment under certain condition you can use `cache_if` or `cache_unless` +If you want to cache a fragment under certain conditions, you can use `cache_if` or `cache_unless` ```erb <% cache_if (condition, cache_key_for_products) do %> diff --git a/guides/source/command_line.md b/guides/source/command_line.md index e72bc81766..7567a38aef 100644 --- a/guides/source/command_line.md +++ b/guides/source/command_line.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + The Rails Command Line ====================== @@ -24,7 +26,7 @@ There are a few commands that are absolutely critical to your everyday usage of * `rails dbconsole` * `rails new app_name` -All commands can run with ```-h or --help``` to list more information. +All commands can run with `-h` or `--help` to list more information. Let's create a simple Rails application to step through each of these commands in context. @@ -61,7 +63,7 @@ With no further work, `rails server` will run our new shiny Rails app: $ cd commandsapp $ bin/rails server => Booting WEBrick -=> Rails 4.2.0 application starting in development on http://localhost:3000 +=> Rails 5.0.0 application starting in development on http://localhost:3000 => Call with -d to detach => Ctrl-C to shutdown server [2013-08-07 02:00:01] INFO WEBrick 1.3.1 @@ -151,9 +153,9 @@ $ bin/rails generate controller Greetings hello create app/helpers/greetings_helper.rb invoke assets invoke coffee - create app/assets/javascripts/greetings.js.coffee + create app/assets/javascripts/greetings.coffee invoke scss - create app/assets/stylesheets/greetings.css.scss + create app/assets/stylesheets/greetings.scss ``` What all did this generate? It made sure a bunch of directories were in our application, and created a controller file, a view file, a functional test file, a helper for the view, a JavaScript file and a stylesheet file. @@ -239,11 +241,11 @@ $ bin/rails generate scaffold HighScore game:string score:integer create app/views/high_scores/show.json.jbuilder invoke assets invoke coffee - create app/assets/javascripts/high_scores.js.coffee + create app/assets/javascripts/high_scores.coffee invoke scss - create app/assets/stylesheets/high_scores.css.scss + create app/assets/stylesheets/high_scores.scss invoke scss - identical app/assets/stylesheets/scaffolds.css.scss + identical app/assets/stylesheets/scaffolds.scss ``` The generator checks that there exist the directories for models, controllers, helpers, layouts, functional and unit tests, stylesheets, creates the views, controller, model and database migration for HighScore (creating the `high_scores` table and fields), takes care of the route for the **resource**, and new tests for everything. @@ -284,7 +286,7 @@ If you wish to test out some code without changing any data, you can do that by ```bash $ bin/rails console --sandbox -Loading development environment in sandbox (Rails 4.2.0) +Loading development environment in sandbox (Rails 5.0.0) Any modifications you make will be rolled back on exit irb(main):001:0> ``` @@ -368,7 +370,7 @@ Rake is Ruby Make, a standalone Ruby utility that replaces the Unix utility 'mak You can get a list of Rake tasks available to you, which will often depend on your current directory, by typing `rake --tasks`. Each task has a description, and should help you find the thing you need. -To get the full backtrace for running rake task you can pass the option ```--trace``` to command line, for example ```rake db:create --trace```. +To get the full backtrace for running rake task you can pass the option `--trace` to command line, for example `rake db:create --trace`. ```bash $ bin/rake --tasks @@ -381,10 +383,10 @@ rake db:create # Create the database from config/database.yml for the c rake log:clear # Truncates all *.log files in log/ to zero bytes (specify which logs with LOGS=test,development) rake middleware # Prints out your Rack middleware stack ... -rake tmp:clear # Clear session, cache, and socket files from tmp/ (narrow w/ tmp:sessions:clear, tmp:cache:clear, tmp:sockets:clear) -rake tmp:create # Creates tmp directories for sessions, cache, sockets, and pids +rake tmp:clear # Clear cache and socket files from tmp/ (narrow w/ tmp:cache:clear, tmp:sockets:clear) +rake tmp:create # Creates tmp directories for cache, sockets, and pids ``` -INFO: You can also use ```rake -T``` to get the list of tasks. +INFO: You can also use `rake -T` to get the list of tasks. ### `about` @@ -393,10 +395,10 @@ INFO: You can also use ```rake -T``` to get the list of tasks. ```bash $ bin/rake about About your application's environment -Rails version 4.2.0 -Ruby version 1.9.3 (x86_64-linux) -RubyGems version 1.3.6 -Rack version 1.3 +Rails version 5.0.0 +Ruby version 2.2.0 (x86_64-linux) +RubyGems version 2.4.5 +Rack version 1.6 JavaScript Runtime Node.js (V8) Middleware Rack::Sendfile, ActionDispatch::Static, Rack::Lock, #<ActiveSupport::Cache::Strategy::LocalCache::Middleware:0x007ffd131a7c88>, Rack::Runtime, Rack::MethodOverride, ActionDispatch::RequestId, Rails::Rack::Logger, ActionDispatch::ShowExceptions, ActionDispatch::DebugExceptions, ActionDispatch::RemoteIp, ActionDispatch::Reloader, ActionDispatch::Callbacks, ActiveRecord::Migration::CheckPending, ActiveRecord::ConnectionAdapters::ConnectionManagement, ActiveRecord::QueryCache, ActionDispatch::Cookies, ActionDispatch::Session::CookieStore, ActionDispatch::Flash, ActionDispatch::ParamsParser, Rack::Head, Rack::ConditionalGet, Rack::ETag Application root /home/foobar/commandsapp @@ -494,15 +496,14 @@ Rails comes with a test suite called Minitest. Rails owes its stability to the u ### `tmp` -The `Rails.root/tmp` directory is, like the *nix /tmp directory, the holding place for temporary files like sessions (if you're using a file store for sessions), process id files, and cached actions. +The `Rails.root/tmp` directory is, like the *nix /tmp directory, the holding place for temporary files like process id files and cached actions. The `tmp:` namespaced tasks will help you clear and create the `Rails.root/tmp` directory: * `rake tmp:cache:clear` clears `tmp/cache`. -* `rake tmp:sessions:clear` clears `tmp/sessions`. * `rake tmp:sockets:clear` clears `tmp/sockets`. -* `rake tmp:clear` clears all the three: cache, sessions and sockets. -* `rake tmp:create` creates tmp directories for sessions, cache, sockets, and pids. +* `rake tmp:clear` clears all cache and sockets files. +* `rake tmp:create` creates tmp directories for cache, sockets and pids. ### Miscellaneous diff --git a/guides/source/configuring.md b/guides/source/configuring.md index 2957232186..5baab8a4b5 100644 --- a/guides/source/configuring.md +++ b/guides/source/configuring.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + Configuring Rails Applications ============================== @@ -120,7 +122,7 @@ numbers. New applications filter out passwords by adding the following `config.f * `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.serve_static_assets` configures Rails itself to serve static assets. Defaults to true, but in the production environment is turned off as the server software (e.g. NGINX or Apache) used to run the application should serve static assets instead. Unlike the default setting set this to true when running (absolutely not recommended!) or testing your app in production mode using WEBrick. Otherwise you won't be able use page caching and requests for files that exist regularly under the public directory will anyway hit your Rails app. +* `config.serve_static_files` configures Rails to serve static files. 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` 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: @@ -197,7 +199,7 @@ The full set of methods that can be used in this block are as follows: Every Rails application comes with a standard set of middleware which it uses in this order in the development environment: * `ActionDispatch::SSL` forces every request to be under HTTPS protocol. Will be available if `config.force_ssl` is set to `true`. Options passed to this can be configured by using `config.ssl_options`. -* `ActionDispatch::Static` is used to serve static assets. Disabled if `config.serve_static_assets` is `false`. +* `ActionDispatch::Static` is used to serve static assets. Disabled if `config.serve_static_files` is `false`. * `Rack::Lock` wraps the app in mutex so it can only be called by a single thread at a time. Only enabled when `config.cache_classes` is `false`. * `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. @@ -214,7 +216,7 @@ Every Rails application comes with a standard set of middleware which it uses in * `ActionDispatch::Flash` sets up the `flash` keys. Only available if `config.action_controller.session_store` is set to a value. * `ActionDispatch::ParamsParser` parses out parameters from the request into `params`. * `Rack::MethodOverride` allows the method to be overridden if `params[:_method]` is set. This is the middleware which supports the PATCH, PUT, and DELETE HTTP method types. -* `ActionDispatch::Head` converts HEAD requests to GET requests and serves them as so. +* `Rack::Head` converts HEAD requests to GET requests and serves them as so. Besides these usual middleware, you can add your own by using the `config.middleware.use` method: @@ -225,13 +227,13 @@ config.middleware.use Magical::Unicorns This will put the `Magical::Unicorns` middleware on the end of the stack. You can use `insert_before` if you wish to add a middleware before another. ```ruby -config.middleware.insert_before ActionDispatch::Head, Magical::Unicorns +config.middleware.insert_before Rack::Head, Magical::Unicorns ``` There's also `insert_after` which will insert a middleware after another: ```ruby -config.middleware.insert_after ActionDispatch::Head, Magical::Unicorns +config.middleware.insert_after Rack::Head, Magical::Unicorns ``` Middlewares can also be completely swapped out and replaced with others: @@ -318,6 +320,8 @@ The schema dumper adds one additional configuration option: * `config.action_controller.default_charset` specifies the default character set for all renders. The default is "utf-8". +* `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.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. * `config.action_controller.request_forgery_protection_token` sets the token parameter name for RequestForgery. Calling `protect_from_forgery` sets it to `:authenticity_token` by default. @@ -503,6 +507,8 @@ 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`. +* `config.active_support.halt_callback_chains_on_return_false` specifies whether ActiveRecord, ActiveModel and ActiveModel::Validations callback chains can be halted by returning `false` in a 'before' callback. Defaults to `true`. + * `ActiveSupport::Logger.silencer` is set to `false` to disable the ability to silence logging in a block. The default is `true`. * `ActiveSupport::Cache::Store.logger` specifies the logger to use within cache store operations. diff --git a/guides/source/contributing_to_ruby_on_rails.md b/guides/source/contributing_to_ruby_on_rails.md index 4eb360cc7a..db3f19f8ac 100644 --- a/guides/source/contributing_to_ruby_on_rails.md +++ b/guides/source/contributing_to_ruby_on_rails.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + Contributing to Ruby on Rails ============================= @@ -24,7 +26,7 @@ NOTE: Bugs in the most recent released version of Ruby on Rails are likely to ge ### Creating a Bug Report -If you've found a problem in Ruby on Rails which is not a security risk, do a search in GitHub under [Issues](https://github.com/rails/rails/issues) in case it has already been reported. If you do not find any issue addressing it you may proceed to [open a new one](https://github.com/rails/rails/issues/new). (See the next section for reporting security issues.) +If you've found a problem in Ruby on Rails which is not a security risk, do a search in GitHub under [Issues](https://github.com/rails/rails/issues) in case it has already been reported. If you are unable to find any open GitHub issues addressing the problem you found, your next step will be to [open a new one](https://github.com/rails/rails/issues/new). (See the next section for reporting security issues.) Your issue report should contain a title and a clear description of the issue at the bare minimum. You should include as much relevant information as possible and should at least post a code sample that demonstrates the issue. It would be even better if you could include a unit test that shows how the expected behavior is not occurring. Your goal should be to make it easy for yourself - and others - to replicate the bug and figure out a fix. @@ -205,7 +207,7 @@ Rails follows a simple set of coding style conventions: * Use Ruby >= 1.9 syntax for hashes. Prefer `{ a: :b }` over `{ :a => :b }`. * Prefer `&&`/`||` over `and`/`or`. * Prefer class << self over self.method for class methods. -* Use `MyClass.my_method(my_arg)` not `my_method( my_arg )` or `my_method my_arg`. +* Use `my_method(my_arg)` not `my_method( my_arg )` or `my_method my_arg`. * Use `a = b` and not `a=b`. * Use assert_not methods instead of refute. * Prefer `method { do_stuff }` instead of `method{do_stuff}` for single-line blocks. @@ -287,7 +289,12 @@ $ ruby -w -Itest test/mail_layout_test.rb -n test_explicit_class_layout The `-n` option allows you to run a single method instead of the whole file. -##### Testing Active Record +#### Testing Active Record + +First, create the databases you'll need. For MySQL and PostgreSQL, +running the SQL statements `create database activerecord_unittest` and +`create database activerecord_unittest2` is sufficient. This is not +necessary for SQLite3. This is how you run the Active Record test suite only for SQLite3: diff --git a/guides/source/debugging_rails_applications.md b/guides/source/debugging_rails_applications.md index 1a647f8375..cef9ac083b 100644 --- a/guides/source/debugging_rails_applications.md +++ b/guides/source/debugging_rails_applications.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + Debugging Rails Applications ============================ @@ -309,7 +311,7 @@ For example: ```bash => Booting WEBrick -=> Rails 4.2.0 application starting in development on http://0.0.0.0:3000 +=> Rails 5.0.0 application starting in development on http://0.0.0.0:3000 => Run `rails server -h` for more startup options => Notice: server is listening on all interfaces (0.0.0.0). Consider using 127.0.0.1 (--binding option) => Ctrl-C to shutdown server @@ -422,11 +424,11 @@ then `backtrace` will supply the answer. --> #0 ArticlesController.index at /PathTo/project/test_app/app/controllers/articles_controller.rb:8 #1 ActionController::ImplicitRender.send_action(method#String, *args#Array) - at /PathToGems/actionpack-4.2.0/lib/action_controller/metal/implicit_render.rb:4 + at /PathToGems/actionpack-5.0.0/lib/action_controller/metal/implicit_render.rb:4 #2 AbstractController::Base.process_action(action#NilClass, *args#Array) - at /PathToGems/actionpack-4.2.0/lib/abstract_controller/base.rb:189 + at /PathToGems/actionpack-5.0.0/lib/abstract_controller/base.rb:189 #3 ActionController::Rendering.process_action(action#NilClass, *args#NilClass) - at /PathToGems/actionpack-4.2.0/lib/action_controller/metal/rendering.rb:10 + at /PathToGems/actionpack-5.0.0/lib/action_controller/metal/rendering.rb:10 ... ``` @@ -438,7 +440,7 @@ context. ``` (byebug) frame 2 -[184, 193] in /PathToGems/actionpack-4.2.0/lib/abstract_controller/base.rb +[184, 193] in /PathToGems/actionpack-5.0.0/lib/abstract_controller/base.rb 184: # is the intended way to override action dispatching. 185: # 186: # Notice that the first argument is the method to be dispatched @@ -655,7 +657,7 @@ instruction to be executed. In this case, the activesupport's `week` method. ``` (byebug) step -[50, 59] in /PathToGems/activesupport-4.2.0/lib/active_support/core_ext/numeric/time.rb +[50, 59] in /PathToGems/activesupport-5.0.0/lib/active_support/core_ext/numeric/time.rb 50: ActiveSupport::Duration.new(self * 24.hours, [[:days, self]]) 51: end 52: alias :day :days diff --git a/guides/source/development_dependencies_install.md b/guides/source/development_dependencies_install.md index 3d9ec578ae..9eacc3a2fe 100644 --- a/guides/source/development_dependencies_install.md +++ b/guides/source/development_dependencies_install.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + Development Dependencies Install ================================ diff --git a/guides/source/documents.yaml b/guides/source/documents.yaml index 4c98d3e1d5..67032a31f5 100644 --- a/guides/source/documents.yaml +++ b/guides/source/documents.yaml @@ -85,9 +85,9 @@ description: This guide provides you with all you need to get started in creating, enqueueing and executing background jobs. - name: Testing Rails Applications - url: testing.html work_in_progress: true - description: This is a rather comprehensive guide to doing both unit and functional tests in Rails. It covers everything from 'What is a test?' to the testing APIs. Enjoy. + url: testing.html + description: This is a rather comprehensive guide to the various testing facilities in Rails. It covers everything from 'What is a test?' to the testing APIs. Enjoy. - name: Securing Rails Applications url: security.html @@ -113,15 +113,25 @@ url: working_with_javascript_in_rails.html description: This guide covers the built-in Ajax/JavaScript functionality of Rails. - - name: Getting Started with Engines - url: engines.html - description: This guide explains how to write a mountable engine. - work_in_progress: true - - name: The Rails Initialization Process work_in_progress: true url: initialization.html description: This guide explains the internals of the Rails initialization process as of Rails 4 + - + name: Autoloading and Reloading Constants + url: autoloading_and_reloading_constants.html + description: This guide documents how autoloading and reloading constants work. + - + name: Active Support Instrumentation + work_in_progress: true + url: active_support_instrumentation.html + description: This guide explains how to use the instrumentation API inside of Active Support to measure events inside of Rails and other Ruby code. + - + name: Profiling Rails Applications + work_in_progress: true + url: profiling.html + description: This guide explains how to profile your Rails applications to improve performance. + - name: Extending Rails documents: @@ -138,6 +148,11 @@ name: Creating and Customizing Rails Generators url: generators.html description: This guide covers the process of adding a brand new generator to your extension or providing an alternative to an element of a built-in Rails generator (such as providing alternative test stubs for the scaffold generator). + - + name: Getting Started with Engines + url: engines.html + description: This guide explains how to write a mountable engine. + work_in_progress: true - name: Contributing to Ruby on Rails documents: @@ -171,7 +186,6 @@ name: Ruby on Rails 4.2 Release Notes url: 4_2_release_notes.html description: Release notes for Rails 4.2. - work_in_progress: true - name: Ruby on Rails 4.1 Release Notes url: 4_1_release_notes.html diff --git a/guides/source/engines.md b/guides/source/engines.md index 21ac941ac0..731178787f 100644 --- a/guides/source/engines.md +++ b/guides/source/engines.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + Getting Started with Engines ============================ @@ -32,7 +34,7 @@ directory structure, and are both generated using the `rails plugin new` generator. The difference is that an engine is considered a "full plugin" by Rails (as indicated by the `--full` option that's passed to the generator command). We'll actually be using the `--mountable` option here, which includes -all the features of `--full`, and then some. This guide will refer to these +all the features of `--full`, and then some. This guide will refer to these "full plugins" simply as "engines" throughout. An engine **can** be a plugin, and a plugin **can** be an engine. @@ -1036,31 +1038,42 @@ functionality, especially controllers. This means that if you were to make a typical `GET` to a controller in a controller's functional test like this: ```ruby -get :index +module Blorgh + class FooControllerTest < ActionController::TestCase + def test_index + get :index + ... + end + end +end ``` It may not function correctly. This is because the application doesn't know how to route these requests to the engine unless you explicitly tell it **how**. To -do this, you must also pass the `:use_route` option as a parameter on these -requests: +do this, you must set the `@routes` instance variable to the engine's route set +in your setup code: ```ruby -get :index, use_route: :blorgh +module Blorgh + class FooControllerTest < ActionController::TestCase + setup do + @routes = Engine.routes + end + + def test_index + get :index + ... + end + end +end ``` This tells the application that you still want to perform a `GET` request to the `index` action of this controller, but you want to use the engine's route to get there, rather than the application's one. -Another way to do this is to assign the `@routes` instance variable to `Engine.routes` in your test setup: - -```ruby -setup do - @routes = Engine.routes -end -``` - -This will also ensure url helpers for the engine will work as expected in your tests. +This also ensures that the engine's URL helpers will work as expected in your +tests. Improving engine functionality ------------------------------ @@ -1155,7 +1168,7 @@ end Using `Class#class_eval` is great for simple adjustments, but for more complex class modifications, you might want to consider using [`ActiveSupport::Concern`] -(http://edgeapi.rubyonrails.org/classes/ActiveSupport/Concern.html). +(http://api.rubyonrails.org/classes/ActiveSupport/Concern.html). ActiveSupport::Concern manages load order of interlinked dependent modules and classes at run time allowing you to significantly modularize your code. diff --git a/guides/source/form_helpers.md b/guides/source/form_helpers.md index cb45e38614..a8dcd3ee4f 100644 --- a/guides/source/form_helpers.md +++ b/guides/source/form_helpers.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + Form Helpers ============ @@ -96,7 +98,15 @@ form_tag({controller: "people", action: "search"}, method: "get", class: "nifty_ ### Helpers for Generating Form Elements -Rails provides a series of helpers for generating form elements such as checkboxes, text fields, and radio buttons. These basic helpers, with names ending in "_tag" (such as `text_field_tag` and `check_box_tag`), generate just a single `<input>` element. The first parameter to these is always the name of the input. When the form is submitted, the name will be passed along with the form data, and will make its way to the `params` hash in the controller with the value entered by the user for that field. For example, if the form contains `<%= text_field_tag(:query) %>`, then you would be able to get the value of this field in the controller with `params[:query]`. +Rails provides a series of helpers for generating form elements such as +checkboxes, text fields, and radio buttons. These basic helpers, with names +ending in `_tag` (such as `text_field_tag` and `check_box_tag`), generate just a +single `<input>` element. The first parameter to these is always the name of the +input. When the form is submitted, the name will be passed along with the form +data, and will make its way to the `params` hash in the controller with the +value entered by the user for that field. For example, if the form contains `<%= +text_field_tag(:query) %>`, then you would be able to get the value of this +field in the controller with `params[:query]`. When naming inputs, Rails uses certain conventions that make it possible to submit parameters with non-scalar values such as arrays or hashes, which will also be accessible in `params`. You can read more about them in [chapter 7 of this guide](#understanding-parameter-naming-conventions). For details on the precise usage of these helpers, please refer to the [API documentation](http://api.rubyonrails.org/classes/ActionView/Helpers/FormTagHelper.html). diff --git a/guides/source/generators.md b/guides/source/generators.md index f5d2c67cb4..05bf07b4c8 100644 --- a/guides/source/generators.md +++ b/guides/source/generators.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + Creating and Customizing Rails Generators & Templates ===================================================== @@ -197,11 +199,11 @@ $ bin/rails generate scaffold User name:string create app/views/users/show.json.jbuilder invoke assets invoke coffee - create app/assets/javascripts/users.js.coffee + create app/assets/javascripts/users.coffee invoke scss - create app/assets/stylesheets/users.css.scss + create app/assets/stylesheets/users.scss invoke scss - create app/assets/stylesheets/scaffolds.css.scss + create app/assets/stylesheets/scaffolds.scss ``` Looking at this output, it's easy to understand how generators work in Rails 3.0 and above. The scaffold generator doesn't actually generate anything, it just invokes others to do the work. This allows us to add/replace/remove any of those invocations. For instance, the scaffold generator invokes the scaffold_controller generator, which invokes erb, test_unit and helper generators. Since each generator has a single responsibility, they are easy to reuse, avoiding code duplication. @@ -407,7 +409,7 @@ $ bin/rails generate scaffold Comment body:text create app/views/comments/show.json.jbuilder invoke assets invoke coffee - create app/assets/javascripts/comments.js.coffee + create app/assets/javascripts/comments.coffee invoke scss ``` diff --git a/guides/source/getting_started.md b/guides/source/getting_started.md index 1996158e27..d80622ef00 100644 --- a/guides/source/getting_started.md +++ b/guides/source/getting_started.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + Getting Started with Rails ========================== @@ -90,18 +92,18 @@ current version of Ruby installed: TIP: A number of tools exist to help you quickly install Ruby and Ruby on Rails on your system. Windows users can use [Rails Installer](http://railsinstaller.org), while Mac OS X users can use [Tokaido](https://github.com/tokaido/tokaidoapp). +For more installation methods for most Operating Systems take a look at +[ruby-lang.org](https://www.ruby-lang.org/en/documentation/installation/). ```bash $ ruby -v ruby 2.0.0p353 ``` -If you don't have Ruby installed have a look at -[ruby-lang.org](https://www.ruby-lang.org/en/installation/) for possible ways to -install Ruby on your platform. - -Many popular UNIX-like OSes ship with an acceptable version of SQLite3. Windows -users and others can find installation instructions at [the SQLite3 website](https://www.sqlite.org). +Many popular UNIX-like OSes ship with an acceptable version of SQLite3. +On Windows, if you installed Rails through Rails Installer, you +already have SQLite installed. Others can find installation instructions +at the [SQLite3 website](https://www.sqlite.org). Verify that it is correctly installed and in your PATH: ```bash @@ -123,7 +125,7 @@ run the following: $ rails --version ``` -If it says something like "Rails 4.2.0", you are ready to continue. +If it says something like "Rails 5.0.0", you are ready to continue. ### Creating the Blog Application @@ -165,14 +167,14 @@ of the files and folders that Rails created by default: |config/|Configure your application's routes, database, and more. This is covered in more detail in [Configuring Rails Applications](configuring.html).| |config.ru|Rack configuration for Rack based servers used to start the application.| |db/|Contains your current database schema, as well as the database migrations.| -|Gemfile<br>Gemfile.lock|These files allow you to specify what gem dependencies are needed for your Rails application. These files are used by the Bundler gem. For more information about Bundler, see [the Bundler website](http://bundler.io).| +|Gemfile<br>Gemfile.lock|These files allow you to specify what gem dependencies are needed for your Rails application. These files are used by the Bundler gem. For more information about Bundler, see the [Bundler website](http://bundler.io).| |lib/|Extended modules for your application.| |log/|Application log files.| |public/|The only folder seen by the world as-is. Contains static files and compiled assets.| |Rakefile|This file locates and loads tasks that can be run from the command line. The task definitions are defined throughout the components of Rails. Rather than changing Rakefile, you should add your own tasks by adding files to the lib/tasks directory of your application.| |README.rdoc|This is a brief instruction manual for your application. You should edit this file to tell others what your application does, how to set it up, and so on.| |test/|Unit tests, fixtures, and other test apparatus. These are covered in [Testing Rails Applications](testing.html).| -|tmp/|Temporary files (like cache, pid, and session files).| +|tmp/|Temporary files (like cache and pid files).| |vendor/|A place for all third-party code. In a typical Rails application this includes vendored gems.| Hello, Rails! @@ -259,9 +261,9 @@ invoke helper create app/helpers/welcome_helper.rb invoke assets invoke coffee -create app/assets/javascripts/welcome.js.coffee +create app/assets/javascripts/welcome.coffee invoke scss -create app/assets/stylesheets/welcome.css.scss +create app/assets/stylesheets/welcome.scss ``` Most important of these are of course the controller, located at @@ -300,8 +302,9 @@ Rails.application.routes.draw do # ... ``` -This is your application's _routing file_ which holds entries in a special DSL -(domain-specific language) that tells Rails how to connect incoming requests to +This is your application's _routing file_ which holds entries in a special +[DSL (domain-specific language)](http://en.wikipedia.org/wiki/Domain-specific_language) +that tells Rails how to connect incoming requests to controllers and actions. This file contains many sample routes on commented lines, and one of them actually shows you how to connect the root of your site to a specific controller and action. Find the line beginning with `root` and @@ -422,12 +425,12 @@ If you refresh <http://localhost:3000/articles/new> now, you'll get a new error: This error indicates that Rails cannot find the `new` action inside the `ArticlesController` that you just generated. This is because when controllers are generated in Rails they are empty by default, unless you tell it -your wanted actions during the generation process. +your desired actions during the generation process. To manually define an action inside a controller, all you need to do is to define a new method inside the controller. Open `app/controllers/articles_controller.rb` and inside the `ArticlesController` -class, define a `new` method so that the controller now looks like this: +class, define the `new` method so that your controller now looks like this: ```ruby class ArticlesController < ApplicationController @@ -444,23 +447,23 @@ With the `new` method defined in `ArticlesController`, if you refresh You're getting this error now because Rails expects plain actions like this one to have views associated with them to display their information. With no view -available, Rails errors out. +available, Rails will raise an exception. In the above image, the bottom line has been truncated. Let's see what the full -thing looks like: +error message looks like: >Missing template articles/new, application/new with {locale:[:en], formats:[:html], handlers:[:erb, :builder, :coffee]}. Searched in: * "/path/to/blog/app/views" That's quite a lot of text! Let's quickly go through and understand what each -part of it does. +part of it means. -The first part identifies what template is missing. In this case, it's the +The first part identifies which template is missing. In this case, it's the `articles/new` template. Rails will first look for this template. If not found, then it will attempt to load a template called `application/new`. It looks for one here because the `ArticlesController` inherits from `ApplicationController`. The next part of the message contains a hash. The `:locale` key in this hash -simply indicates what spoken language template should be retrieved. By default, +simply indicates which spoken language template should be retrieved. By default, this is the English - or "en" - template. The next key, `:formats` specifies the format of template to be served in response. The default format is `:html`, and so Rails is looking for an HTML template. The final key, `:handlers`, is telling @@ -473,14 +476,16 @@ Templates within a basic Rails application like this are kept in a single location, but in more complex applications it could be many different paths. The simplest template that would work in this case would be one located at -`app/views/articles/new.html.erb`. The extension of this file name is key: the -first extension is the _format_ of the template, and the second extension is the -_handler_ that will be used. Rails is attempting to find a template called -`articles/new` within `app/views` for the application. The format for this -template can only be `html` and the handler must be one of `erb`, `builder` or -`coffee`. Because you want to create a new HTML form, you will be using the `ERB` -language. Therefore the file should be called `articles/new.html.erb` and needs -to be located inside the `app/views` directory of the application. +`app/views/articles/new.html.erb`. The extension of this file name is important: +the first extension is the _format_ of the template, and the second extension +is the _handler_ that will be used. Rails is attempting to find a template +called `articles/new` within `app/views` for the application. The format for +this template can only be `html` and the handler must be one of `erb`, +`builder` or `coffee`. Because you want to create a new HTML form, you will be +using the `ERB` language which is designed to embed Ruby in HTML. + +Therefore the file should be called `articles/new.html.erb` and needs to be +located inside the `app/views` directory of the application. Go ahead now and create a new file at `app/views/articles/new.html.erb` and write this content in it: @@ -665,8 +670,8 @@ rake commands to run migrations, and it's possible to undo a migration after it's been applied to your database. Migration filenames include a timestamp to ensure that they're processed in the order that they were created. -If you look in the `db/migrate/20140120191729_create_articles.rb` file (remember, -yours will have a slightly different name), here's what you'll find: +If you look in the `db/migrate/YYYYMMDDHHMMSS_create_articles.rb` file +(remember, yours will have a slightly different name), here's what you'll find: ```ruby class CreateArticles < ActiveRecord::Migration @@ -675,7 +680,7 @@ class CreateArticles < ActiveRecord::Migration t.string :title t.text :text - t.timestamps + t.timestamps null: false end end end @@ -736,7 +741,7 @@ database columns. In the first line we do just that (remember that `@article.save` is responsible for saving the model in the database. Finally, we redirect the user to the `show` action, which we'll define later. -TIP: You might be wondering why the `A` in `Article.new` is capitalized above, whereas most other references to articles in this guide have used lowercase. In this context, we are referring to the class named `Article` that is defined in `\models\article.rb`. Class names in Ruby must begin with a capital letter. +TIP: You might be wondering why the `A` in `Article.new` is capitalized above, whereas most other references to articles in this guide have used lowercase. In this context, we are referring to the class named `Article` that is defined in `app/models/article.rb`. Class names in Ruby must begin with a capital letter. TIP: As we'll see later, `@article.save` returns a boolean indicating whether the article was saved or not. @@ -833,7 +838,7 @@ class ArticlesController < ApplicationController A couple of things to note. We use `Article.find` to find the article we're interested in, passing in `params[:id]` to get the `:id` parameter from the -request. We also use an instance variable (prefixed by `@`) to hold a +request. We also use an instance variable (prefixed with `@`) to hold a reference to the article object. We do this because Rails will pass all instance variables to the view. @@ -1279,7 +1284,7 @@ And here's how our app looks so far: Our `edit` page looks very similar to the `new` page; in fact, they both share the same code for displaying the form. Let's remove this duplication by using a view partial. By convention, partial files are -prefixed by an underscore. +prefixed with an underscore. TIP: You can read more about partials in the [Layouts and Rendering in Rails](layouts_and_rendering.html) guide. @@ -1537,8 +1542,9 @@ class CreateComments < ActiveRecord::Migration # this line adds an integer column called `article_id`. t.references :article, index: true - t.timestamps + t.timestamps null: false end + add_foreign_key :comments, :articles end end ``` @@ -1558,6 +1564,8 @@ run against the current database, so in this case you will just see: == CreateComments: migrating ================================================= -- create_table(:comments) -> 0.0115s +-- add_foreign_key(:comments, :articles) + -> 0.0000s == CreateComments: migrated (0.0119s) ======================================== ``` @@ -1635,8 +1643,8 @@ This creates five files and one empty directory: | app/views/comments/ | Views of the controller are stored here | | test/controllers/comments_controller_test.rb | The test for the controller | | app/helpers/comments_helper.rb | A view helper file | -| app/assets/javascripts/comment.js.coffee | CoffeeScript for the controller | -| app/assets/stylesheets/comment.css.scss | Cascading style sheet for the controller | +| app/assets/javascripts/comment.coffee | CoffeeScript for the controller | +| app/assets/stylesheets/comment.scss | Cascading style sheet for the controller | Like with any blog, our readers will create their comments directly after reading the article, and once they have added their comment, will be sent back @@ -2029,9 +2037,11 @@ What's Next? ------------ Now that you've seen your first Rails application, you should feel free to -update it and experiment on your own. But you don't have to do everything -without help. As you need assistance getting up and running with Rails, feel -free to consult these support resources: +update it and experiment on your own. + +Remember you don't have to do everything without help. As you need assistance +getting up and running with Rails, feel free to consult these support +resources: * The [Ruby on Rails Guides](index.html) * The [Ruby on Rails Tutorial](http://railstutorial.org/book) @@ -2049,7 +2059,7 @@ command-line utility: in your web browser to explore the API documentation. TIP: To be able to generate the Rails Guides locally with the `doc:guides` rake -task you need to install the RedCloth and Nokogiri gems. Add it to your `Gemfile` and run +task you need to install the Redcarpet and Nokogiri gems. Add it to your `Gemfile` and run `bundle install` and you're ready to go. Configuration Gotchas diff --git a/guides/source/i18n.md b/guides/source/i18n.md index f6cbc1823a..bd6babff41 100644 --- a/guides/source/i18n.md +++ b/guides/source/i18n.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + Rails Internationalization (I18n) API ===================================== @@ -626,7 +628,7 @@ entry[count == 1 ? 0 : 1] I.e. the translation denoted as `:one` is regarded as singular, the other is used as plural (including the count being zero). -If the lookup for the key does not return a Hash suitable for pluralization, an `18n::InvalidPluralizationData` exception is raised. +If the lookup for the key does not return a Hash suitable for pluralization, an `I18n::InvalidPluralizationData` exception is raised. ### Setting and Passing a Locale diff --git a/guides/source/initialization.md b/guides/source/initialization.md index 53bf3039fa..a93ceb7fb5 100644 --- a/guides/source/initialization.md +++ b/guides/source/initialization.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + The Rails Initialization Process ================================ @@ -357,7 +359,7 @@ private end def create_tmp_directories - %w(cache pids sessions sockets).each do |dir_to_make| + %w(cache pids sockets).each do |dir_to_make| FileUtils.mkdir_p(File.join(Rails.root, 'tmp', dir_to_make)) end end @@ -373,13 +375,12 @@ private end ``` -This is where the first output of the Rails initialization happens. This -method creates a trap for `INT` signals, so if you `CTRL-C` the server, -it will exit the process. As we can see from the code here, it will -create the `tmp/cache`, `tmp/pids`, `tmp/sessions` and `tmp/sockets` -directories. It then calls `wrapped_app` which is responsible for -creating the Rack app, before creating and assigning an -instance of `ActiveSupport::Logger`. +This is where the first output of the Rails initialization happens. This method +creates a trap for `INT` signals, so if you `CTRL-C` the server, it will exit the +process. As we can see from the code here, it will create the `tmp/cache`, +`tmp/pids`, and `tmp/sockets` directories. It then calls `wrapped_app` which is +responsible for creating the Rack app, before creating and assigning an instance +of `ActiveSupport::Logger`. The `super` method will call `Rack::Server.start` which begins its definition like this: diff --git a/guides/source/layouts_and_rendering.md b/guides/source/layouts_and_rendering.md index ae16ad86cd..c3cde49630 100644 --- a/guides/source/layouts_and_rendering.md +++ b/guides/source/layouts_and_rendering.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + Layouts and Rendering in Rails ============================== @@ -425,6 +427,9 @@ Rails understands both numeric status codes and the corresponding symbols shown | | 510 | :not_extended | | | 511 | :network_authentication_required | +NOTE: If you try to render content along with a non-content status code +(100-199, 204, 205 or 304), it will be dropped from the response. + #### Finding Layouts To find the current layout, Rails first looks for a file in `app/views/layouts` with the same base name as the controller. For example, rendering actions from the `PhotosController` class will use `app/views/layouts/photos.html.erb` (or `app/views/layouts/photos.builder`). If there is no such controller-specific layout, Rails will use `app/views/layouts/application.html.erb` or `app/views/layouts/application.builder`. If there is no `.erb` layout, Rails will use a `.builder` layout if one exists. Rails also provides several ways to more precisely assign specific layouts to individual controllers and actions. @@ -904,7 +909,10 @@ You can also specify multiple videos to play by passing an array of videos to th This will produce: ```erb -<video><source src="/videos/trailer.ogg" /><source src="/videos/trailer.flv" /></video> +<video> + <source src="/videos/trailer.ogg"> + <source src="/videos/movie.ogg"> +</video> ``` #### Linking to Audio Files with the `audio_tag` @@ -1022,6 +1030,42 @@ One way to use partials is to treat them as the equivalent of subroutines: as a Here, the `_ad_banner.html.erb` and `_footer.html.erb` partials could contain content that is shared among many pages in your application. You don't need to see the details of these sections when you're concentrating on a particular page. +As you already could see from the previous sections of this guide, `yield` is a very powerful tool for cleaning up your layouts. Keep in mind that it's pure ruby, so you can use it almost everywhere. For example, we can use it to DRY form layout definition for several similar resources: + +* `users/index.html.erb` + + ```html+erb + <%= render "shared/search_filters", search: @q do |f| %> + <p> + Name contains: <%= f.text_field :name_contains %> + </p> + <%= end %> + ``` + +* `roles/index.html.erb` + + ```html+erb + <%= render "shared/search_filters", search: @q do |f| %> + <p> + Title contains: <%= f.text_field :title_contains %> + </p> + <%= end %> + ``` + +* `shared/_search_filters.html.erb` + + ```html+erb + <%= form_for(@q) do |f| %> + <h1>Search form:</h1> + <fieldset> + <%= yield f %> + </fieldset> + <p> + <%= f.submit "Search" %> + </p> + <% end %> + ``` + TIP: For content that is shared among all pages in your application, you can use partials directly from layouts. #### Partial Layouts diff --git a/guides/source/maintenance_policy.md b/guides/source/maintenance_policy.md index 050a64ddf3..45cdc549f7 100644 --- a/guides/source/maintenance_policy.md +++ b/guides/source/maintenance_policy.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + Maintenance Policy for Ruby on Rails ==================================== diff --git a/guides/source/nested_model_forms.md b/guides/source/nested_model_forms.md index f0ee34cfb1..44236ad239 100644 --- a/guides/source/nested_model_forms.md +++ b/guides/source/nested_model_forms.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + Rails Nested Model Forms ======================== diff --git a/guides/source/plugins.md b/guides/source/plugins.md index 7b7eb80081..bd884441ac 100644 --- a/guides/source/plugins.md +++ b/guides/source/plugins.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + The Basics of Creating Rails Plugins ==================================== @@ -433,7 +435,7 @@ Once your README is solid, go through and add rdoc comments to all of the method Once your comments are good to go, navigate to your plugin directory and run: ```bash -$ bin/rake rdoc +$ bundle exec rake rdoc ``` ### References diff --git a/guides/source/profiling.md b/guides/source/profiling.md new file mode 100644 index 0000000000..695b09647f --- /dev/null +++ b/guides/source/profiling.md @@ -0,0 +1,16 @@ +*DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + +A Guide to Profiling Rails Applications +======================================= + +This guide covers built-in mechanisms in Rails for profiling your application. + +After reading this guide, you will know: + +* Rails profiling terminology. +* How to write benchmark tests for your application. +* Other benchmarking approaches and plugins. + +-------------------------------------------------------------------------------- + + diff --git a/guides/source/rails_application_templates.md b/guides/source/rails_application_templates.md index 6512b14e60..0db777b9bb 100644 --- a/guides/source/rails_application_templates.md +++ b/guides/source/rails_application_templates.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + Rails Application Templates =========================== diff --git a/guides/source/rails_on_rack.md b/guides/source/rails_on_rack.md index 8bc2678d8f..561a3d9392 100644 --- a/guides/source/rails_on_rack.md +++ b/guides/source/rails_on_rack.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + Rails on Rack ============= @@ -61,7 +63,6 @@ Here's how it loads the middlewares: ```ruby def middleware middlewares = [] - middlewares << [Rails::Rack::Debugger] if options[:debugger] middlewares << [::Rack::ContentLength] Hash.new(middlewares) end @@ -233,7 +234,7 @@ Much of Action Controller's functionality is implemented as Middlewares. The fol **`ActionDispatch::Static`** -* Used to serve static assets. Disabled if `config.serve_static_assets` is `false`. +* Used to serve static files. Disabled if `config.serve_static_files` is `false`. **`Rack::Lock`** @@ -277,7 +278,7 @@ Much of Action Controller's functionality is implemented as Middlewares. The fol **`ActionDispatch::Callbacks`** -* Runs the prepare callbacks before serving the request. +* Provides callbacks to be executed before and after dispatching the request. **`ActiveRecord::Migration::CheckPending`** @@ -307,7 +308,7 @@ Much of Action Controller's functionality is implemented as Middlewares. The fol * Parses out parameters from the request into `params`. -**`ActionDispatch::Head`** +**`Rack::Head`** * Converts HEAD requests to `GET` requests and serves them as so. diff --git a/guides/source/routing.md b/guides/source/routing.md index b1a287f53a..893cedeefc 100644 --- a/guides/source/routing.md +++ b/guides/source/routing.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + Rails Routing from the Outside In ================================= diff --git a/guides/source/ruby_on_rails_guides_guidelines.md b/guides/source/ruby_on_rails_guides_guidelines.md index c0438f6341..0ecf8a80df 100644 --- a/guides/source/ruby_on_rails_guides_guidelines.md +++ b/guides/source/ruby_on_rails_guides_guidelines.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + Ruby on Rails Guides Guidelines =============================== diff --git a/guides/source/security.md b/guides/source/security.md index 125dd82666..e4cc79df55 100644 --- a/guides/source/security.md +++ b/guides/source/security.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + Ruby on Rails Security Guide ============================ @@ -237,7 +239,7 @@ Or the attacker places the code into the onmouseover event handler of an image: <img src="http://www.harmless.com/img" width="400" height="400" onmouseover="..." /> ``` -There are many other possibilities, like using a `<script>` tag to make a cross-site request to a URL with a JSONP or JavaScript response. The response is executable code that the attacker can find a way to run, possibly extracting sensitive data. To protect against this data leakage, we disallow cross-site `<script>` tags. Only Ajax requests may have JavaScript responses since XmlHttpRequest is subject to the browser Same-Origin policy - meaning only your site can initiate the request. +There are many other possibilities, like using a `<script>` tag to make a cross-site request to a URL with a JSONP or JavaScript response. The response is executable code that the attacker can find a way to run, possibly extracting sensitive data. To protect against this data leakage, we disallow cross-site `<script>` tags. Only Ajax requests may have JavaScript responses since `XMLHttpRequest` is subject to the browser Same-Origin policy - meaning only your site can initiate the request. To protect against all other forged requests, we introduce a _required security token_ that our site knows but other sites don't know. We include the security token in requests and verify it on the server. This is a one-liner in your application controller, and is the default for newly created rails applications: @@ -247,6 +249,15 @@ protect_from_forgery with: :exception This will automatically include a security token in all forms and Ajax requests generated by Rails. If the security token doesn't match what was expected, an exception will be thrown. +NOTE: By default, Rails includes jQuery and an [unobtrusive scripting adapter for +jQuery](https://github.com/rails/jquery-ujs), which adds a header called +`X-CSRF-Token` on every non-GET Ajax call made by jQuery with the security token. +Without this header, non-GET Ajax requests won't be accepted by Rails. When using +another library to make Ajax calls, it is necessary to add the security token as +a default header for Ajax calls in your library. To get the token, have a look at +`<meta name='csrf-token' content='THE-TOKEN'>` tag printed by +`<%= csrf_meta_tags %>` in your application view. + It is common to use persistent cookies to store user information, with `cookies.permanent` for example. In this case, the cookies will not be cleared and the out of the box CSRF protection will not be effective. If you are using a different cookie store than the session for this information, you must handle what to do with it yourself: ```ruby @@ -362,7 +373,7 @@ Refer to the Injection section for countermeasures against XSS. It is _recommend **CSRF** Cross-Site Request Forgery (CSRF), also known as Cross-Site Reference Forgery (XSRF), is a gigantic attack method, it allows the attacker to do everything the administrator or Intranet user may do. As you have already seen above how CSRF works, here are a few examples of what attackers can do in the Intranet or admin interface. -A real-world example is a [router reconfiguration by CSRF](http://www.h-online.com/security/Symantec-reports-first-active-attack-on-a-DSL-router--/news/102352). The attackers sent a malicious e-mail, with CSRF in it, to Mexican users. The e-mail claimed there was an e-card waiting for them, but it also contained an image tag that resulted in a HTTP-GET request to reconfigure the user's router (which is a popular model in Mexico). The request changed the DNS-settings so that requests to a Mexico-based banking site would be mapped to the attacker's site. Everyone who accessed the banking site through that router saw the attacker's fake web site and had their credentials stolen. +A real-world example is a [router reconfiguration by CSRF](http://www.h-online.com/security/news/item/Symantec-reports-first-active-attack-on-a-DSL-router-735883.html). The attackers sent a malicious e-mail, with CSRF in it, to Mexican users. The e-mail claimed there was an e-card waiting for them, but it also contained an image tag that resulted in a HTTP-GET request to reconfigure the user's router (which is a popular model in Mexico). The request changed the DNS-settings so that requests to a Mexico-based banking site would be mapped to the attacker's site. Everyone who accessed the banking site through that router saw the attacker's fake web site and had their credentials stolen. Another example changed Google Adsense's e-mail address and password by. If the victim was logged into Google Adsense, the administration interface for Google advertisements campaigns, an attacker could change their credentials.
 @@ -942,7 +953,7 @@ unless params[:token].nil? end ``` -When `params[:token]` is one of: `[]`, `[nil]`, `[nil, nil, ...]` or +When `params[:token]` is one of: `[nil]`, `[nil, nil, ...]` or `['foo', nil]` it will bypass the test for `nil`, but `IS NULL` or `IN ('foo', NULL)` where clauses still will be added to the SQL query. @@ -953,9 +964,9 @@ request: | JSON | Parameters | |-----------------------------------|--------------------------| | `{ "person": null }` | `{ :person => nil }` | -| `{ "person": [] }` | `{ :person => nil }` | -| `{ "person": [null] }` | `{ :person => nil }` | -| `{ "person": [null, null, ...] }` | `{ :person => nil }` | +| `{ "person": [] }` | `{ :person => [] }` | +| `{ "person": [null] }` | `{ :person => [] }` | +| `{ "person": [null, null, ...] }` | `{ :person => [] }` | | `{ "person": ["foo", null] }` | `{ :person => ["foo"] }` | It is possible to return to old behaviour and disable `deep_munge` configuring diff --git a/guides/source/testing.md b/guides/source/testing.md index b4c70dfa1d..21b0b37efa 100644 --- a/guides/source/testing.md +++ b/guides/source/testing.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + A Guide to Testing Rails Applications ===================================== @@ -29,11 +31,13 @@ Testing support was woven into the Rails fabric from the beginning. It wasn't an By default, every Rails application has three environments: development, test, and production. The database for each one of them is configured in `config/database.yml`. -A dedicated test database allows you to set up and interact with test data in isolation. Tests can mangle test data with confidence, that won't touch the data in the development or production databases. +A dedicated test database allows you to set up and interact with test data in isolation. This way your tests can mangle test data with confidence, without worrying about the data in the development or production databases. + +Also, each environment's configuration can be modified similarly. In this case, we can modify our test environment by changing the options found in `config/environments/test.rb`. ### Rails Sets up for Testing from the Word Go -Rails creates a `test` folder for you as soon as you create a Rails project using `rails new` _application_name_. If you list the contents of this folder then you shall see: +Rails creates a `test` directory for you as soon as you create a Rails project using `rails new` _application_name_. If you list the contents of this directory then you shall see: ```bash $ ls -F test @@ -41,9 +45,9 @@ controllers/ helpers/ mailers/ test_helper.rb fixtures/ integration/ models/ ``` -The `models` directory is meant to hold tests for your models, the `controllers` directory is meant to hold tests for your controllers and the `integration` directory is meant to hold tests that involve any number of controllers interacting. +The `models` directory is meant to hold tests for your models, the `controllers` directory is meant to hold tests for your controllers and the `integration` directory is meant to hold tests that involve any number of controllers interacting. There is also a directory for testing your mailers and one for testing view helpers. -Fixtures are a way of organizing test data; they reside in the `fixtures` folder. +Fixtures are a way of organizing test data; they reside in the `fixtures` directory. The `test_helper.rb` file holds the default configuration for your tests. @@ -51,7 +55,7 @@ The `test_helper.rb` file holds the default configuration for your tests. For good tests, you'll need to give some thought to setting up test data. In Rails, you can handle this by defining and customizing fixtures. -You can find comprehensive documentation in the [fixture api documentation](http://api.rubyonrails.org/classes/ActiveRecord/FixtureSet.html). +You can find comprehensive documentation in the [Fixtures API documentation](http://api.rubyonrails.org/classes/ActiveRecord/FixtureSet.html). #### What Are Fixtures? @@ -61,7 +65,7 @@ You'll find fixtures under your `test/fixtures` directory. When you run `rails g #### YAML -YAML-formatted fixtures are a very human-friendly way to describe your sample data. These types of fixtures have the **.yml** file extension (as in `users.yml`). +YAML-formatted fixtures are a human-friendly way to describe your sample data. These types of fixtures have the **.yml** file extension (as in `users.yml`). Here's a sample YAML fixture file: @@ -78,7 +82,7 @@ steve: profession: guy with keyboard ``` -Each fixture is given a name followed by an indented list of colon-separated key/value pairs. Records are typically separated by a blank space. You can place comments in a fixture file by using the # character in the first column. Keys which resemble YAML keywords such as 'yes' and 'no' are quoted so that the YAML Parser correctly interprets them. +Each fixture is given a name followed by an indented list of colon-separated key/value pairs. Records are typically separated by a blank space. You can place comments in a fixture file by using the # character in the first column. If you are working with [associations](/association_basics.html), you can simply define a reference node between two different fixtures. Here's an example with @@ -96,11 +100,9 @@ one: category: about ``` -Note: For associations to reference one another by name, you cannot specify the `id:` - attribute on the fixtures. Rails will auto assign a primary key to be consistent between - runs. If you manually specify an `id:` attribute, this behavior will not work. For more - information on this association behavior please read the - [fixture api documentation](http://api.rubyonrails.org/classes/ActiveRecord/FixtureSet.html). +Notice the `category` key of the `one` article found in `fixtures/articles.yml` has a value of `about`. This tells Rails to load the category `about` found in `fixtures/categories.yml`. + +NOTE: For associations to reference one another by name, you cannot specify the `id:` attribute on the associated fixtures. Rails will auto assign a primary key to be consistent between runs. For more information on this association behavior please read the [Fixtures API documentation](http://api.rubyonrails.org/classes/ActiveRecord/FixtureSet.html). #### ERB'in It Up @@ -116,15 +118,17 @@ user_<%= n %>: #### Fixtures in Action -Rails by default automatically loads all fixtures from the `test/fixtures` folder for your models and controllers test. Loading involves three steps: +Rails by default automatically loads all fixtures from the `test/fixtures` directory for your models and controllers test. Loading involves three steps: * Remove any existing data from the table corresponding to the fixture * Load the fixture data into the table -* Dump the fixture data into a variable in case you want to access it directly +* Dump the fixture data into a method in case you want to access it directly + +TIP: In order to remove existing data from the database, Rails tries to disable referential integrity triggers (like foreign keys and check constraints). If you are getting annoying permission errors on running tests, make sure the database user has privilege to disable these triggers in testing environment. (In PostgreSQL, only superusers can disable all triggers. Read more about PostgreSQL permissions [here](http://blog.endpoint.com/2012/10/postgres-system-triggers-error.html)) #### Fixtures are Active Record objects -Fixtures are instances of Active Record. As mentioned in point #3 above, you can access the object directly because it is automatically setup as a local variable of the test case. For example: +Fixtures are instances of Active Record. As mentioned in point #3 above, you can access the object directly because it is automatically available as a method whose scope is local of the test case. For example: ```ruby # this will return the User object for the fixture named david @@ -137,16 +141,35 @@ users(:david).id email(david.girlfriend.email, david.location_tonight) ``` +### Rake Tasks for Running your Tests + +Rails comes with a number of built-in rake tasks to help with testing. The +table below lists the commands included in the default Rakefile when a Rails +project is created. + +| Tasks | Description | +| ----------------------- | ----------- | +| `rake test` | Runs all tests in the `test` directory. You can also run `rake` and Rails will run all tests by default | +| `rake test:controllers` | Runs all the controller tests from `test/controllers` | +| `rake test:functionals` | Runs all the functional tests from `test/controllers`, `test/mailers`, and `test/functional` | +| `rake test:helpers` | Runs all the helper tests from `test/helpers` | +| `rake test:integration` | Runs all the integration tests from `test/integration` | +| `rake test:jobs` | Runs all the job tests from `test/jobs` | +| `rake test:mailers` | Runs all the mailer tests from `test/mailers` | +| `rake test:models` | Runs all the model tests from `test/models` | +| `rake test:units` | Runs all the unit tests from `test/models`, `test/helpers`, and `test/unit` | +| `rake test:db` | Runs all tests in the `test` directory and resets the db | + +We will cover each of types Rails tests listed above in this guide. + Unit Testing your Models ------------------------ -In Rails, models tests are what you write to test your models. - -For this guide we will be using Rails _scaffolding_. It will create the model, a migration, controller and views for the new resource in a single operation. It will also create a full test suite following Rails best practices. We will be using examples from this generated code and will be supplementing it with additional examples where necessary. +In Rails, unit tests are what you write to test your models. -NOTE: For more information on Rails _scaffolding_, refer to [Getting Started with Rails](getting_started.html) +For this guide we will be using the application we built in the [Getting Started with Rails](getting_started.html) guide. -When you use `rails generate scaffold`, for a resource among other things it creates a test stub in the `test/models` folder: +If you remember when you used the `rails generate scaffold` command from earlier. We created our first resource among other things it created a test stub in the `test/models` directory: ```bash $ bin/rails generate scaffold article title:string body:text @@ -175,18 +198,18 @@ A line by line examination of this file will help get you oriented to Rails test require 'test_helper' ``` -As you know by now, `test_helper.rb` specifies the default configuration to run our tests. This is included with all the tests, so any methods added to this file are available to all your tests. +By requiring this file, `test_helper.rb` the default configuration to run our tests is loaded. We will include this with all the tests we write, so any methods added to this file are available to all your tests. ```ruby class ArticleTest < ActiveSupport::TestCase ``` -The `ArticleTest` class defines a _test case_ because it inherits from `ActiveSupport::TestCase`. `ArticleTest` thus has all the methods available from `ActiveSupport::TestCase`. You'll see those methods a little later in this guide. +The `ArticleTest` class defines a _test case_ because it inherits from `ActiveSupport::TestCase`. `ArticleTest` thus has all the methods available from `ActiveSupport::TestCase`. Later in this guide, you'll see some of the methods it gives you. Any method defined within a class inherited from `Minitest::Test` -(which is the superclass of `ActiveSupport::TestCase`) that begins with `test_` (case sensitive) is simply called a test. So, `test_password` and `test_valid_password` are legal test names and are run automatically when the test case is run. +(which is the superclass of `ActiveSupport::TestCase`) that begins with `test_` (case sensitive) is simply called a test. So, methods defined as `test_password` and `test_valid_password` are legal test names and are run automatically when the test case is run. -Rails adds a `test` method that takes a test name and a block. It generates a normal `Minitest::Unit` test with method names prefixed with `test_`. So, +Rails also adds a `test` method that takes a test name and a block. It generates a normal `Minitest::Unit` test with method names prefixed with `test_`. So you don't have to worry about naming the methods, and you can write something like: ```ruby test "the truth" do @@ -194,7 +217,7 @@ test "the truth" do end ``` -acts as if you had written +Which is approximately the same as writing this: ```ruby def test_the_truth @@ -202,26 +225,37 @@ def test_the_truth end ``` -only the `test` macro allows a more readable test name. You can still use regular method definitions though. +However only the `test` macro allows a more readable test name. You can still use regular method definitions though. -NOTE: The method name is generated by replacing spaces with underscores. The result does not need to be a valid Ruby identifier though, the name may contain punctuation characters etc. That's because in Ruby technically any string may be a method name. Odd ones need `define_method` and `send` calls, but formally there's no restriction. +NOTE: The method name is generated by replacing spaces with underscores. The result does not need to be a valid Ruby identifier though, the name may contain punctuation characters etc. That's because in Ruby technically any string may be a method name. This may require use of `define_method` and `send` calls to function properly, but formally there's little restriction on the name. + +Next, let's look at our first assertion: ```ruby assert true ``` -This line of code is called an _assertion_. An assertion is a line of code that evaluates an object (or expression) for expected results. For example, an assertion can check: +An assertion is a line of code that evaluates an object (or expression) for expected results. For example, an assertion can check: * does this value = that value? * is this object nil? * does this line of code throw an exception? * is the user's password greater than 5 characters? -Every test contains one or more assertions. Only when all the assertions are successful will the test pass. +Every test must contain at least one assertion, with no restriction as to how many assertions are allowed. Only when all the assertions are successful will the test pass. ### Maintaining the test database schema -In order to run your tests, your test database will need to have the current structure. The test helper checks whether your test database has any pending migrations. If so, it will try to load your `db/schema.rb` or `db/structure.sql` into the test database. If migrations are still pending, an error will be raised. +In order to run your tests, your test database will need to have the current +structure. The test helper checks whether your test database has any pending +migrations. If so, it will try to load your `db/schema.rb` or `db/structure.sql` +into the test database. If migrations are still pending, an error will be +raised. Usually this indicates that your schema is not fully migrated. Running +the migrations against the development database (`bin/rake db:migrate`) will +bring the schema up to date. + +NOTE: If existing migrations required modifications, the test database needs to +be rebuilt. This can be done by executing `bin/rake db:test:prepare`. ### Running Tests @@ -247,10 +281,12 @@ Finished tests in 0.009064s, 110.3266 tests/s, 110.3266 assertions/s. 1 tests, 1 assertions, 0 failures, 0 errors, 0 skips ``` -This will run all test methods from the test case. Note that `test_helper.rb` is in the `test` directory, hence this directory needs to be added to the load path using the `-I` switch. +This will run all test methods from the test case. The `.` (dot) above indicates a passing test. When a test fails you see an `F`; when a test throws an error you see an `E` in its place. The last line of the output is the summary. +#### Your first failing test + To see how a test failure is reported, you can add a failing test to the `article_test.rb` test case. ```ruby @@ -313,7 +349,7 @@ Finished tests in 0.047721s, 20.9551 tests/s, 20.9551 assertions/s. Now, if you noticed, we first wrote a test which fails for a desired functionality, then we wrote some code which adds the functionality and finally we ensured that our test passes. This approach to software development is referred to as _Test-Driven Development_ (TDD). -TIP: Many Rails developers practice _Test-Driven Development_ (TDD). This is an excellent way to build up a test suite that exercises every part of your application. TDD is beyond the scope of this guide, but one place to start is with [15 TDD steps to create a Rails application](http://andrzejonsoftware.blogspot.com/2007/05/15-tdd-steps-to-create-rails.html). +#### What an error looks like To see how an error gets reported, here's a test containing an error: @@ -356,52 +392,26 @@ behavior: $ BACKTRACE=1 bin/rake test test/models/article_test.rb ``` -### What to Include in Your Unit Tests +If we want this test to pass we can modify it to use `assert_raises` like so: -Ideally, you would like to include a test for everything which could possibly break. It's a good practice to have at least one test for each of your validations and at least one test for every method in your model. +```ruby +test "should report error" do + # some_undefined_variable is not defined elsewhere in the test case + assert_raises(NameError) do + some_undefined_variable + end +end +``` + +This test should now pass. ### Available Assertions By now you've caught a glimpse of some of the assertions that are available. Assertions are the worker bees of testing. They are the ones that actually perform the checks to ensure that things are going as planned. -There are a bunch of different types of assertions you can use. -Here's an extract of the assertions you can use with [`Minitest`](https://github.com/seattlerb/minitest), the default testing library used by Rails. The `[msg]` parameter is an optional string message you can specify to make your test failure messages clearer. It's not required. - -| Assertion | Purpose | -| ---------------------------------------------------------------- | ------- | -| `assert( test, [msg] )` | Ensures that `test` is true.| -| `assert_not( test, [msg] )` | Ensures that `test` is false.| -| `assert_equal( expected, actual, [msg] )` | Ensures that `expected == actual` is true.| -| `assert_not_equal( expected, actual, [msg] )` | Ensures that `expected != actual` is true.| -| `assert_same( expected, actual, [msg] )` | Ensures that `expected.equal?(actual)` is true.| -| `assert_not_same( expected, actual, [msg] )` | Ensures that `expected.equal?(actual)` is false.| -| `assert_nil( obj, [msg] )` | Ensures that `obj.nil?` is true.| -| `assert_not_nil( obj, [msg] )` | Ensures that `obj.nil?` is false.| -| `assert_empty( obj, [msg] )` | Ensures that `obj` is `empty?`.| -| `assert_not_empty( obj, [msg] )` | Ensures that `obj` is not `empty?`.| -| `assert_match( regexp, string, [msg] )` | Ensures that a string matches the regular expression.| -| `assert_no_match( regexp, string, [msg] )` | Ensures that a string doesn't match the regular expression.| -| `assert_includes( collection, obj, [msg] )` | Ensures that `obj` is in `collection`.| -| `assert_not_includes( collection, obj, [msg] )` | Ensures that `obj` is not in `collection`.| -| `assert_in_delta( expecting, actual, [delta], [msg] )` | Ensures that the numbers `expected` and `actual` are within `delta` of each other.| -| `assert_not_in_delta( expecting, actual, [delta], [msg] )` | Ensures that the numbers `expected` and `actual` are not within `delta` of each other.| -| `assert_throws( symbol, [msg] ) { block }` | Ensures that the given block throws the symbol.| -| `assert_raises( exception1, exception2, ... ) { block }` | Ensures that the given block raises one of the given exceptions.| -| `assert_nothing_raised( exception1, exception2, ... ) { block }` | Ensures that the given block doesn't raise one of the given exceptions.| -| `assert_instance_of( class, obj, [msg] )` | Ensures that `obj` is an instance of `class`.| -| `assert_not_instance_of( class, obj, [msg] )` | Ensures that `obj` is not an instance of `class`.| -| `assert_kind_of( class, obj, [msg] )` | Ensures that `obj` is or descends from `class`.| -| `assert_not_kind_of( class, obj, [msg] )` | Ensures that `obj` is not an instance of `class` and is not descending from it.| -| `assert_respond_to( obj, symbol, [msg] )` | Ensures that `obj` responds to `symbol`.| -| `assert_not_respond_to( obj, symbol, [msg] )` | Ensures that `obj` does not respond to `symbol`.| -| `assert_operator( obj1, operator, [obj2], [msg] )` | Ensures that `obj1.operator(obj2)` is true.| -| `assert_not_operator( obj1, operator, [obj2], [msg] )` | Ensures that `obj1.operator(obj2)` is false.| -| `assert_predicate ( obj, predicate, [msg] )` | Ensures that `obj.predicate` is true, e.g. `assert_predicate str, :empty?`| -| `assert_not_predicate ( obj, predicate, [msg] )` | Ensures that `obj.predicate` is false, e.g. `assert_not_predicate str, :empty?`| -| `assert_send( array, [msg] )` | Ensures that executing the method listed in `array[1]` on the object in `array[0]` with the parameters of `array[2 and up]` is true. This one is weird eh?| -| `flunk( [msg] )` | Ensures failure. This is useful to explicitly mark a test that isn't finished yet.| - -The above are subset of assertions that minitest supports. For an exhaustive & more up-to-date list, please check [Minitest API documentation](http://docs.seattlerb.org/minitest/), specifically [`Minitest::Assertions`](http://docs.seattlerb.org/minitest/Minitest/Assertions.html) +There are a bunch of different types of assertions you can use that come with [`Minitest`](https://github.com/seattlerb/minitest), the default testing library used by Rails. + +For a list of all available assertions please check the [Minitest API documentation](http://docs.seattlerb.org/minitest/), specifically [`Minitest::Assertions`](http://docs.seattlerb.org/minitest/Minitest/Assertions.html) Because of the modular nature of the testing framework, it is possible to create your own assertions. In fact, that's exactly what Rails does. It includes some specialized assertions to make your life easier. @@ -423,10 +433,24 @@ Rails adds some custom assertions of its own to the `minitest` framework: You'll see the usage of some of these assertions in the next chapter. +### A Brief Note About Minitest + +All the basic assertions such as `assert_equal` defined in `Minitest::Assertions` are also available in the classes we use in our own test cases. In fact, Rails provides the following classes for you to inherit from: + +* `ActiveSupport::TestCase` +* `ActionController::TestCase` +* `ActionMailer::TestCase` +* `ActionView::TestCase` +* `ActionDispatch::IntegrationTest` + +Each of these classes include `Minitest::Assertions`, allowing us to use all of the basic assertions in our tests. + +NOTE: For more information on `Minitest`, refer to [Minitest](http://ruby-doc.org/stdlib-2.1.0/libdoc/minitest/rdoc/MiniTest.html) + Functional Tests for Your Controllers ------------------------------------- -In Rails, testing the various actions of a single controller is called writing functional tests for that controller. Controllers handle the incoming web requests to your application and eventually respond with a rendered view. +In Rails, testing the various actions of a controller is a form of writing functional tests. Remember your controllers handle the incoming web requests to your application and eventually respond with a rendered view. When writing functional tests, you're testing how your actions handle the requests and the expected result, or response in some cases an HTML view. ### What to Include in your Functional Tests @@ -500,13 +524,13 @@ If you're familiar with the HTTP protocol, you'll know that `get` is a type of r * `head` * `delete` -All of request types are methods that you can use, however, you'll probably end up using the first two more often than the others. +All of request types have equivalent methods that you can use. In a typical C.R.U.D. application you'll be using `get`, `post`, `put` and `delete` more often. -NOTE: Functional tests do not verify whether the specified request type should be accepted by the action. Request types in this context exist to make your tests more descriptive. +NOTE: Functional tests do not verify whether the specified request type is accepted by the action, we're more concerned with the result. Request tests exist for this use case to make your tests more purposeful. ### The Four Hashes of the Apocalypse -After a request has been made using one of the 6 methods (`get`, `post`, etc.) and processed, you will have 4 Hash objects ready for use: +After a request has been made and processed, you will have 4 Hash objects ready for use: * `assigns` - Any objects that are stored as instance variables in actions for use in views. * `cookies` - Any cookies that are set. @@ -529,8 +553,8 @@ assigns["something"] assigns(:something) You also have access to three instance variables in your functional tests: * `@controller` - The controller processing the request -* `@request` - The request -* `@response` - The response +* `@request` - The request object +* `@response` - The response object ### Setting Headers and CGI variables @@ -551,6 +575,10 @@ post :create # simulate the request with custom env variable ### Testing Templates and Layouts +Eventually, you may want to test whether a specific layout is rendered in the view of a response. + +#### Asserting Templates + If you want to make sure that the response rendered the correct template and layout, you can use the `assert_template` method: @@ -559,24 +587,22 @@ test "index should render correct template and layout" do get :index assert_template :index assert_template layout: "layouts/application" + + # You can also pass a regular expression. + assert_template layout: /layouts\/application/ end ``` -Note that you cannot test for template and layout at the same time, with one call to `assert_template` method. -Also, for the `layout` test, you can give a regular expression instead of a string, but using the string, makes -things clearer. On the other hand, you have to include the "layouts" directory name even if you save your layout -file in this standard layout directory. Hence, +NOTE: You cannot test for template and layout at the same time, with a single call to `assert_template`. -```ruby -assert_template layout: "application" -``` +WARNING: You must include the "layouts" directory name even if you save your layout file in this standard layout directory. Hence, `assert_template layout: "application"` will not work. -will not work. +#### Asserting Partials -If your view renders any partial, when asserting for the layout, you have to assert for the partial at the same time. +If your view renders any partial, when asserting for the layout, you can to assert for the partial at the same time. Otherwise, assertion will fail. -Hence: +Remember, we added the "_form" partial to our creating Articles view? Let's write an assertion for that in the `:new` action now: ```ruby test "new should render correct layout" do @@ -585,27 +611,201 @@ test "new should render correct layout" do end ``` -is the correct way to assert for the layout when the view renders a partial with name `_form`. Omitting the `:partial` key in your `assert_template` call will complain. +This is the correct way to assert for when the view renders a partial with a given name. As identified by the `:partial` key passed to the `assert_template` call. + +### Testing `flash` notices + +If you remember from earlier one of the Four Hashes of the Apocalypse was `flash`. -### A Fuller Functional Test Example +We want to add a `flash` message to our blog application whenever someone +successfully creates a new Article. -Here's another example that uses `flash`, `assert_redirected_to`, and `assert_difference`: +Let's start by adding this assertion to our `test_should_create_article` test: ```ruby test "should create article" do assert_difference('Article.count') do - post :create, article: {title: 'Hi', body: 'This is my first article.'} + post :create, article: {title: 'Some title'} end + assert_redirected_to article_path(assigns(:article)) assert_equal 'Article was successfully created.', flash[:notice] end ``` -### Testing Views +If we run our test now, we should see a failure: + +```bash +$ bin/rake test test/controllers/articles_controller_test.rb test_should_create_article +Run options: -n test_should_create_article --seed 32266 + +# Running: + +F + +Finished in 0.114870s, 8.7055 runs/s, 34.8220 assertions/s. + + 1) Failure: +ArticlesControllerTest#test_should_create_article [/Users/zzak/code/bench/sharedapp/test/controllers/articles_controller_test.rb:16]: +--- expected ++++ actual +@@ -1 +1 @@ +-"Article was successfully created." ++nil + +1 runs, 4 assertions, 1 failures, 0 errors, 0 skips +``` + +Let's implement the flash message now in our controller. Our `:create` action should now look like this: + +```ruby +def create + @article = Article.new(article_params) + + if @article.save + flash[:notice] = 'Article was successfully created.' + redirect_to @article + else + render 'new' + end +end +``` + +Now if we run our tests, we should see it pass: -Testing the response to your request by asserting the presence of key HTML elements and their content is a useful way to test the views of your application. The `assert_select` assertion allows you to do this by using a simple yet powerful syntax. +```bash +$ bin/rake test test/controllers/articles_controller_test.rb test_should_create_article +Run options: -n test_should_create_article --seed 18981 + +# Running: + +. + +Finished in 0.081972s, 12.1993 runs/s, 48.7972 assertions/s. -NOTE: You may find references to `assert_tag` in other documentation. This has been removed in 4.2. Use `assert_select` instead. +1 runs, 4 assertions, 0 failures, 0 errors, 0 skips +``` + +### Putting it together + +At this point our Articles controller tests the `:index` as well as `:new` and `:create` actions. What about dealing with existing data? + +Let's write a test for the `:show` action: + +```ruby +test "should show article" do + article = articles(:one) + get :show, id: article.id + assert_response :success +end +``` + +Remember from our discussion earlier on fixtures the `articles()` method will give us access to our Articles fixtures. + +How about deleting an existing Article? + +```ruby +test "should destroy article" do + article = articles(:one) + assert_difference('Article.count', -1) do + delete :destroy, id: article.id + end + + assert_redirected_to articles_path +end +``` + +We can also add a test for updating an existing Article. + +```ruby +test "should update article" do + article = articles(:one) + patch :update, id: article.id, article: {title: "updated"} + assert_redirected_to article_path(assigns(:article)) +end +``` + +Notice we're starting to see some duplication in these three tests, they both access the same Article fixture data. We can D.R.Y. this up by using the `setup` and `teardown` methods provided by `ActiveSupport::Callbacks`. + +Our test should now look something like this, disregard the other tests we're leaving them out for brevity. + +```ruby +require 'test_helper' + +class ArticlesControllerTest < ActionController::TestCase + # called before every single test + def setup + @article = articles(:one) + end + + # called after every single test + def teardown + # as we are re-initializing @article before every test + # setting it to nil here is not essential but I hope + # you understand how you can use the teardown method + @article = nil + end + + test "should show article" do + # Reuse the @article instance variable from setup + get :show, id: @article.id + assert_response :success + end + + test "should destroy article" do + assert_difference('Article.count', -1) do + delete :destroy, id: @article.id + end + + assert_redirected_to articles_path + end + + test "should update article" do + patch :update, id: @article.id, article: {title: "updated"} + assert_redirected_to article_path(assigns(:article)) + end +end +``` + +Similar to other callbacks in Rails, the `setup` and `teardown` methods can also be used by passing a block, lambda, or method name as a symbol to call. + +Testing Routes +-------------- + +Like everything else in your Rails application, it is recommended that you test your routes. Below are example tests for the routes of default `show` and `create` action of `Articles` controller above and it should look like: + +```ruby +class ArticleRoutesTest < ActionController::TestCase + test "should route to article" do + assert_routing '/articles/1', { controller: "articles", action: "show", id: "1" } + end + + test "should route to create article" do + assert_routing({ method: 'post', path: '/articles' }, { controller: "articles", action: "create" }) + end +end +``` + +I've added this file here `test/controllers/articles_routes_test.rb` and if we run the test we should see: + +```bash +$ bin/rake test test/controllers/articles_routes_test.rb + +# Running: + +.. + +Finished in 0.069381s, 28.8263 runs/s, 86.4790 assertions/s. + +2 runs, 6 assertions, 0 failures, 0 errors, 0 skips +``` + +For more information on routing assertions available in Rails, see the API documentation for [`ActionDispatch::Assertions::RoutingAssertions`](http://api.rubyonrails.org/classes/ActionDispatch/Assertions/RoutingAssertions.html). + +Testing Views +------------- + +Testing the response to your request by asserting the presence of key HTML elements and their content is a common way to test the views of your application. The `assert_select` method allows you to query HTML elements of the response by using a simple yet powerful syntax. There are two forms of `assert_select`: @@ -619,7 +819,10 @@ For example, you could verify the contents on the title element in your response assert_select 'title', "Welcome to Rails Testing Guide" ``` -You can also use nested `assert_select` blocks. In this case the inner `assert_select` runs the assertion on the complete collection of elements selected by the outer `assert_select` block: +You can also use nested `assert_select` blocks for deeper investigation. + +In the following example, the inner `assert_select` for `li.menu_item` runs +within the collection of elements selected by the outer block: ```ruby assert_select 'ul.navigation' do @@ -627,7 +830,9 @@ assert_select 'ul.navigation' do end ``` -Alternatively the collection of elements selected by the outer `assert_select` may be iterated through so that `assert_select` may be called separately for each element. Suppose for example that the response contains two ordered lists, each with four list elements then the following tests will both pass. +A collection of selected elements may be iterated through so that `assert_select` may be called separately for each element. + +For example if the response contains two ordered lists, each with four nested list elements then the following tests will both pass. ```ruby assert_select "ol" do |elements| @@ -641,7 +846,7 @@ assert_select "ol" do end ``` -The `assert_select` assertion is quite powerful. For more advanced usage, refer to its [documentation](https://github.com/rails/rails-dom-testing/blob/master/lib/rails/dom/testing/assertions/selector_assertions.rb). +This assertion is quite powerful. For more advanced usage, refer to its [documentation](http://www.rubydoc.info/github/rails/rails-dom-testing). #### Additional View-Based Assertions @@ -661,12 +866,45 @@ assert_select_email do end ``` +Testing helpers +--------------- + +In order to test helpers, all you need to do is check that the output of the +helper method matches what you'd expect. Tests related to the helpers are +located under the `test/helpers` directory. + +A helper test looks like so: + +```ruby +require 'test_helper' + +class UserHelperTest < ActionView::TestCase +end +``` + +A helper is just a simple module where you can define methods which are +available into your views. To test the output of the helper's methods, you just +have to use a mixin like this: + +```ruby +class UserHelperTest < ActionView::TestCase + include UserHelper + + test "should return the user name" do + # ... + end +end +``` + +Moreover, since the test class extends from `ActionView::TestCase`, you have +access to Rails' helper methods such as `link_to` or `pluralize`. + Integration Testing ------------------- -Integration tests are used to test the interaction among any number of controllers. They are generally used to test important work flows within your application. +Integration tests are used to test how various parts of your application interact. They are generally used to test important work flows within your application. -Unlike Unit and Functional tests, integration tests have to be explicitly created under the 'test/integration' folder within your application. Rails provides a generator to create an integration test skeleton for you. +For creating Rails integration tests, we use the 'test/integration' directory for your application. Rails provides a generator to create an integration test skeleton for you. ```bash $ bin/rails generate integration_test user_flows @@ -686,233 +924,92 @@ class UserFlowsTest < ActionDispatch::IntegrationTest end ``` -Integration tests inherit from `ActionDispatch::IntegrationTest`. This makes available some additional helpers to use in your integration tests. Also you need to explicitly include the fixtures to be made available to the test. +Inheriting from `ActionDispatch::IntegrationTest` comes with some advantages. This makes available some additional helpers to use in your integration tests. ### Helpers Available for Integration Tests -In addition to the standard testing helpers, there are some additional helpers available to integration tests: +In addition to the standard testing helpers, inheriting `ActionDispatch::IntegrationTest` comes with some additional helpers available when writing integration tests. Let's briefly introduce you to the three categories of helpers you get to choose from. -| Helper | Purpose | -| ------------------------------------------------------------------ | ------- | -| `https?` | Returns `true` if the session is mimicking a secure HTTPS request.| -| `https!` | Allows you to mimic a secure HTTPS request.| -| `host!` | Allows you to set the host name to use in the next request.| -| `redirect?` | Returns `true` if the last request was a redirect.| -| `follow_redirect!` | Follows a single redirect response.| -| `request_via_redirect(http_method, path, [parameters], [headers])` | Allows you to make an HTTP request and follow any subsequent redirects.| -| `post_via_redirect(path, [parameters], [headers])` | Allows you to make an HTTP POST request and follow any subsequent redirects.| -| `get_via_redirect(path, [parameters], [headers])` | Allows you to make an HTTP GET request and follow any subsequent redirects.| -| `patch_via_redirect(path, [parameters], [headers])` | Allows you to make an HTTP PATCH request and follow any subsequent redirects.| -| `put_via_redirect(path, [parameters], [headers])` | Allows you to make an HTTP PUT request and follow any subsequent redirects.| -| `delete_via_redirect(path, [parameters], [headers])` | Allows you to make an HTTP DELETE request and follow any subsequent redirects.| -| `open_session` | Opens a new session instance.| +For dealing with the integration test runner, see [`ActionDispatch::Integration::Runner`](http://api.rubyonrails.org/classes/ActionDispatch/Integration/Runner.html). -### Integration Testing Examples +When performing requests, you will have [`ActionDispatch::Integration::RequestHelpers`](http://api.rubyonrails.org/classes/ActionDispatch/Integration/RequestHelpers.html) available for your use. -A simple integration test that exercises multiple controllers: +If you'd like to modify the session, or state of your integration test you should look for [`ActionDispatch::Integration::Session`](http://api.rubyonrails.org/classes/ActionDispatch/Integration/Session.html) to help. -```ruby -require 'test_helper' +### Implementing an integration test -class UserFlowsTest < ActionDispatch::IntegrationTest - test "login and browse site" do - # login via https - https! - get "/login" - assert_response :success +Let's add an integration test to our blog application. We'll start with a basic workflow of creating a new blog article, to verify that everything is working properly. - post_via_redirect "/login", username: users(:david).username, password: users(:david).password - assert_equal '/welcome', path - assert_equal 'Welcome david!', flash[:notice] +We'll start by generating our integration test skeleton: - https!(false) - get "/articles/all" - assert_response :success - assert assigns(:articles) - end -end +```bash +$ bin/rails generate integration_test blog_flow ``` -As you can see the integration test involves multiple controllers and exercises the entire stack from database to dispatcher. In addition you can have multiple session instances open simultaneously in a test and extend those instances with assertion methods to create a very powerful testing DSL (domain-specific language) just for your application. +It should have created a test file placeholder for us, with the output of the previous command you should see: -Here's an example of multiple sessions and custom DSL in an integration test +```bash + invoke test_unit + create test/integration/blog_flow_test.rb +``` + +Now let's open that file and write our first assertion: ```ruby require 'test_helper' -class UserFlowsTest < ActionDispatch::IntegrationTest - test "login and browse site" do - # User david logs in - david = login(:david) - # User guest logs in - guest = login(:guest) - - # Both are now available in different sessions - assert_equal 'Welcome david!', david.flash[:notice] - assert_equal 'Welcome guest!', guest.flash[:notice] - - # User david can browse site - david.browses_site - # User guest can browse site as well - guest.browses_site - - # Continue with other assertions +class BlogFlowTest < ActionDispatch::IntegrationTest + test "can see the welcome page" do + get "/" + assert_select "h1", "Welcome#index" end - - private - - module CustomDsl - def browses_site - get "/products/all" - assert_response :success - assert assigns(:products) - end - end - - def login(user) - open_session do |sess| - sess.extend(CustomDsl) - u = users(user) - sess.https! - sess.post "/login", username: u.username, password: u.password - assert_equal '/welcome', sess.path - sess.https!(false) - end - end end ``` -Rake Tasks for Running your Tests ---------------------------------- - -Rails comes with a number of built-in rake tasks to help with testing. The -table below lists the commands included in the default Rakefile when a Rails -project is created. +If you remember from earlier in the "Testing Views" section we covered `assert_select` to query the resulting HTML of a request. -| Tasks | Description | -| ----------------------- | ----------- | -| `rake test` | Runs all tests in the `test` folder. You can also simply run `rake` as Rails will run all the tests by default | -| `rake test:controllers` | Runs all the controller tests from `test/controllers` | -| `rake test:functionals` | Runs all the functional tests from `test/controllers`, `test/mailers`, and `test/functional` | -| `rake test:helpers` | Runs all the helper tests from `test/helpers` | -| `rake test:integration` | Runs all the integration tests from `test/integration` | -| `rake test:jobs` | Runs all the job tests from `test/jobs` | -| `rake test:mailers` | Runs all the mailer tests from `test/mailers` | -| `rake test:models` | Runs all the model tests from `test/models` | -| `rake test:units` | Runs all the unit tests from `test/models`, `test/helpers`, and `test/unit` | -| `rake test:db` | Runs all tests in the `test` folder and resets the db | - - -A Brief Note About Minitest ------------------------------ - -Ruby ships with a vast Standard Library for all common use-cases including testing. Since version 1.9, Ruby provides `Minitest`, a framework for testing. All the basic assertions such as `assert_equal` discussed above are actually defined in `Minitest::Assertions`. The classes `ActiveSupport::TestCase`, `ActionController::TestCase`, `ActionMailer::TestCase`, `ActionView::TestCase` and `ActionDispatch::IntegrationTest` - which we have been inheriting in our test classes - include `Minitest::Assertions`, allowing us to use all of the basic assertions in our tests. +When visit our root path, we should see `welcome/index.html.erb` rendered for the view. So this assertion should pass. -NOTE: For more information on `Minitest`, refer to [Minitest](http://ruby-doc.org/stdlib-2.1.0/libdoc/minitest/rdoc/MiniTest.html) - -Setup and Teardown ------------------- +#### Creating articles integration -If you would like to run a block of code before the start of each test and another block of code after the end of each test you have two special callbacks for your rescue. Let's take note of this by looking at an example for our functional test in `Articles` controller: +How about testing our ability to create a new article in our blog and see the resulting article. ```ruby -require 'test_helper' - -class ArticlesControllerTest < ActionController::TestCase - - # called before every single test - def setup - @article = articles(:one) - end - - # called after every single test - def teardown - # as we are re-initializing @article before every test - # setting it to nil here is not essential but I hope - # you understand how you can use the teardown method - @article = nil - end - - test "should show article" do - get :show, id: @article.id - assert_response :success - end - - test "should destroy article" do - assert_difference('Article.count', -1) do - delete :destroy, id: @article.id - end - - assert_redirected_to articles_path - end - +test "can create an article" do + get "/articles/new" + assert_response :success + assert_template "articles/new", partial: "articles/_form" + + post "/articles", article: {title: "can create", body: "article successfully."} + assert_response :redirect + follow_redirect! + assert_response :success + assert_template "articles/show" + assert_select "p", "Title:\n can create" end ``` -Above, the `setup` method is called before each test and so `@article` is available for each of the tests. Rails implements `setup` and `teardown` as `ActiveSupport::Callbacks`. Which essentially means you need not only use `setup` and `teardown` as methods in your tests. You could specify them by using: +Let's break this test down so we can understand it. -* a block -* a method (like in the earlier example) -* a method name as a symbol -* a lambda +We start by calling the `:new` action on our Articles controller. This response should be successful, and we can verify the correct template is rendered including the form partial. -Let's see the earlier example by specifying `setup` callback by specifying a method name as a symbol: +After this we make a post request to the `:create` action of our Articles controller: ```ruby -require 'test_helper' - -class ArticlesControllerTest < ActionController::TestCase - - # called before every single test - setup :initialize_article - - # called after every single test - def teardown - @article = nil - end - - test "should show article" do - get :show, id: @article.id - assert_response :success - end - - test "should update article" do - patch :update, id: @article.id, article: {} - assert_redirected_to article_path(assigns(:article)) - end - - test "should destroy article" do - assert_difference('Article.count', -1) do - delete :destroy, id: @article.id - end - - assert_redirected_to articles_path - end - - private - - def initialize_article - @article = articles(:one) - end -end +post "/articles", article: {title: "can create", body: "article successfully."} +assert_response :redirect +follow_redirect! ``` -Testing Routes --------------- +The two lines following the request are to handle the redirect we setup when creating a new article. -Like everything else in your Rails application, it is recommended that you test your routes. Below are example tests for the routes of default `show` and `create` action of `Articles` controller above and it should look like: +NOTE: Don't forget to call `follow_redirect!` if you plan to make subsequent requests after a redirect is made. -```ruby -class ArticleRoutesTest < ActionController::TestCase - test "should route to article" do - assert_routing '/articles/1', { controller: "articles", action: "show", id: "1" } - end +Finally we can assert that our response was successful, template was rendered, and our new article is readable on the page. - test "should route to create article" do - assert_routing({ method: 'post', path: '/articles' }, { controller: "articles", action: "create" }) - end -end -``` +#### Taking it further + +We were able to successfully test a very small workflow for visiting our blog and creating a new article. If we wanted to take this further we could add tests for commenting, removing articles, or editting comments. Integration tests are a great place to experiment with all kinds of use-cases for our applications. Testing Your Mailers -------------------- @@ -1014,39 +1111,6 @@ class UserControllerTest < ActionController::TestCase end ``` -Testing helpers ---------------- - -In order to test helpers, all you need to do is check that the output of the -helper method matches what you'd expect. Tests related to the helpers are -located under the `test/helpers` directory. - -A helper test looks like so: - -```ruby -require 'test_helper' - -class UserHelperTest < ActionView::TestCase -end -``` - -A helper is just a simple module where you can define methods which are -available into your views. To test the output of the helper's methods, you just -have to use a mixin like this: - -```ruby -class UserHelperTest < ActionView::TestCase - include UserHelper - - test "should return the user name" do - # ... - end -end -``` - -Moreover, since the test class extends from `ActionView::TestCase`, you have -access to Rails' helper methods such as `link_to` or `pluralize`. - Testing Jobs ------------ @@ -1080,17 +1144,7 @@ no jobs have already been executed in the scope of each test. ### Custom Assertions And Testing Jobs Inside Other Components -Active Job ships with a bunch of custom assertions that can be used to lessen -the verbosity of tests: - -| Assertion | Purpose | -| -------------------------------------- | ------- | -| `assert_enqueued_jobs(number)` | Asserts that the number of enqueued jobs matches the given number. | -| `assert_performed_jobs(number)` | Asserts that the number of performed jobs matches the given number. | -| `assert_no_enqueued_jobs { ... }` | Asserts that no jobs have been enqueued. | -| `assert_no_performed_jobs { ... }` | Asserts that no jobs have been performed. | -| `assert_enqueued_with([args]) { ... }` | Asserts that the job passed in the block has been enqueued with the given arguments. | -| `assert_performed_with([args]) { ... }`| Asserts that the job passed in the block has been performed with the given arguments. | +Active Job ships with a bunch of custom assertions that can be used to lessen the verbosity of tests. For a full list of available assertions, see the API documentation for [`ActiveJob::TestHelper`](http://api.rubyonrails.org/classes/ActiveJob/TestHelper.html). It's a good practice to ensure that your jobs correctly get enqueued or performed wherever you invoke them (e.g. inside your controllers). This is precisely where diff --git a/guides/source/upgrading_ruby_on_rails.md b/guides/source/upgrading_ruby_on_rails.md index 6f5dea45b5..c0c94475e0 100644 --- a/guides/source/upgrading_ruby_on_rails.md +++ b/guides/source/upgrading_ruby_on_rails.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + A Guide for Upgrading Ruby on Rails =================================== @@ -18,9 +20,10 @@ The best way to be sure that your application still works after upgrading is to Rails generally stays close to the latest released Ruby version when it's released: -* Rails 3 and above require Ruby 1.8.7 or higher. Support for all of the previous Ruby versions has been dropped officially. You should upgrade as early as possible. -* Rails 3.2.x is the last branch to support Ruby 1.8.7. +* Rails 5 requires Ruby 2.2 or newer. * Rails 4 prefers Ruby 2.0 and requires 1.9.3 or newer. +* Rails 3.2.x is the last branch to support Ruby 1.8.7. +* Rails 3 and above require Ruby 1.8.7 or higher. Support for all of the previous Ruby versions has been dropped officially. You should upgrade as early as possible. TIP: Ruby 1.8.7 p248 and p249 have marshaling bugs that crash Rails. Ruby Enterprise Edition has these fixed since the release of 1.8.7-2010.02. On the 1.9 front, Ruby 1.9.1 is not usable because it outright segfaults, so if you want to use 1.9.x, jump straight to 1.9.3 for smooth sailing. @@ -47,24 +50,37 @@ Overwrite /myapp/config/application.rb? (enter "h" for help) [Ynaqdh] Don't forget to review the difference, to see if there were any unexpected changes. -Upgrading from Rails 4.1 to Rails 4.2 +Upgrading from Rails 4.2 to Rails 5.0 ------------------------------------- -NOTE: This section is a work in progress, please help to improve this by sending -a [pull request](https://github.com/rails/rails/edit/master/guides/source/upgrading_ruby_on_rails.md). +### Halting callback chains by returning `false` -### Web Console +In Rails 4.2, when a 'before' callback returns `false` in ActiveRecord, +ActiveModel and ActiveModel::Validations, then the entire callback chain +is halted. In other words, successive 'before' callbacks are not executed, +and neither is the action wrapped in callbacks. -First, add `gem 'web-console', '~> 2.0'` to the `:development` group in your Gemfile and run `bundle install` (it won't have been included when you upgraded Rails). Once it's been installed, you can simply drop a reference to the console helper (i.e., `<%= console %>`) into any view you want to enable it for. A console will also be provided on any error page you view in your development environment. +In Rails 5.0, returning `false` in a callback will not have this side effect +of halting the callback chain. Instead, callback chains must be explicitly +halted by calling `throw(:abort)`. -Additionally, you can tell Rails to automatically mount a VT100-compatible console on a predetermined path by setting the appropriate configuration flags in your development config: +When you upgrade from Rails 4.2 to Rails 5.0, returning `false` in a callback +will still halt the callback chain, but you will receive a deprecation warning +about this upcoming change. -```ruby -# config/environments/development.rb +When you are ready, you can opt into the new behavior and remove the deprecation +warning by adding the following configuration to your `config/application.rb`: -config.web_console.automount = true -config.web_console.default_mount_path = '/terminal' # Optional, defaults to /console -``` + config.active_support.halt_callback_chains_on_return_false = false + +See [#17227](https://github.com/rails/rails/pull/17227) for more details. + +Upgrading from Rails 4.1 to Rails 4.2 +------------------------------------- + +### Web Console + +First, add `gem 'web-console', '~> 2.0'` to the `:development` group in your Gemfile and run `bundle install` (it won't have been included when you upgraded Rails). Once it's been installed, you can simply drop a reference to the console helper (i.e., `<%= console %>`) into any view you want to enable it for. A console will also be provided on any error page you view in your development environment. ### Responders @@ -145,6 +161,18 @@ assigning `nil` to a serialized attribute will save it to the database as `NULL` instead of passing the `nil` value through the coder (e.g. `"null"` when using the `JSON` coder). +### Production log level + +In Rails 5, the default log level for the production environment will be changed +to `:debug` (from `:info`). To preserve the current default, add the following +line to your `production.rb`: + +```ruby +# Set to `:info` to match the current default, or set to `:debug` to opt-into +# the future default. +config.log_level = :info +``` + ### `after_bundle` in Rails templates If you have a Rails template that adds all the files in version control, it @@ -207,12 +235,47 @@ gem 'rails-deprecated_sanitizer' ``` ### Rails DOM Testing + The [`TagAssertions` module](http://api.rubyonrails.org/classes/ActionDispatch/Assertions/TagAssertions.html) (containing methods such as `assert_tag`), [has been deprecated](https://github.com/rails/rails/blob/6061472b8c310158a2a2e8e9a6b81a1aef6b60fe/actionpack/lib/action_dispatch/testing/assertions/dom.rb) in favor of the `assert_select` methods from the `SelectorAssertions` module, which has been extracted into the [rails-dom-testing gem](https://github.com/rails/rails-dom-testing). ### Masked Authenticity Tokens + In order to mitigate SSL attacks, `form_authenticity_token` is now masked so that it varies with each request. Thus, tokens are validated by unmasking and then decrypting. As a result, any strategies for verifying requests from non-rails forms that relied on a static session CSRF token have to take this into account. +### Action Mailer + +Previously, calling a mailer method on a mailer class will result in the +corresponding instance method being executed directly. With the introduction of +Active Job and `#deliver_later`, this is no longer true. In Rails 4.2, the +invocation of the instance methods are deferred until either `deliver_now` or +`deliver_later` is called. For example: + +```ruby +class Notifier < ActionMailer::Base + def notify(user, ...) + puts "Called" + mail(to: user.email, ...) + end +end + +mail = Notifier.notify(user, ...) # Notifier#notify is not yet called at this point +mail = mail.deliver_now # Prints "Called" +``` + +This should not result in any noticeable differences for most applications. +However, if you need some non-mailer methods to be executed synchronously, and +you were previously relying on the synchronous proxying behavior, you should +define them as class methods on the mailer class directly: + +```ruby +class Notifier < ActionMailer::Base + def self.broadcast_notifications(users, ...) + users.each { |user| Notifier.notify(user, ...) } + end +end +``` + Upgrading from Rails 4.0 to Rails 4.1 ------------------------------------- @@ -731,7 +794,7 @@ file (in `config/application.rb`): ```ruby # Require the gems listed in Gemfile, including any gems # you've limited to :test, :development, or :production. -Bundler.require(:default, Rails.env) +Bundler.require(*Rails.groups) ``` ### vendor/plugins @@ -950,7 +1013,7 @@ The following changes are meant for upgrading your application to the latest Make the following changes to your `Gemfile`. ```ruby -gem 'rails', '3.2.18' +gem 'rails', '3.2.21' group :assets do gem 'sass-rails', '~> 3.2.6' @@ -1075,7 +1138,7 @@ You can help test performance with these additions to your test environment: ```ruby # Configure static asset server for tests with Cache-Control for performance -config.serve_static_assets = true +config.serve_static_files = true config.static_cache_control = 'public, max-age=3600' ``` diff --git a/guides/source/working_with_javascript_in_rails.md b/guides/source/working_with_javascript_in_rails.md index 7c3fd9f69d..5131f809d7 100644 --- a/guides/source/working_with_javascript_in_rails.md +++ b/guides/source/working_with_javascript_in_rails.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + Working with JavaScript in Rails ================================ |