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diff --git a/guides/source/i18n.md b/guides/source/i18n.md index 0eba3af6e8..4dc4c5a660 100644 --- a/guides/source/i18n.md +++ b/guides/source/i18n.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE ON GITHUB, GUIDES ARE PUBLISHED ON http://guides.rubyonrails.org.** + Rails Internationalization (I18n) API ===================================== @@ -28,7 +30,7 @@ After reading this guide, you will know: -------------------------------------------------------------------------------- -NOTE: The Ruby I18n framework provides you with all necessary means for internationalization/localization of your Rails application. You may, however, use any of various plugins and extensions available, which add additional functionality or features. See the Ruby [I18n Wiki](http://ruby-i18n.org/wiki) for more information. +NOTE: The Ruby I18n framework provides you with all necessary means for internationalization/localization of your Rails application. You may, also use various gems available to add additional functionality or features. See the [rails-i18n gem](https://github.com/svenfuchs/rails-i18n) for more information. How I18n in Ruby on Rails Works ------------------------------- @@ -101,13 +103,13 @@ This means, that in the `:en` locale, the key _hello_ will map to the _Hello wor The I18n library will use **English** as a **default locale**, i.e. if you don't set a different locale, `:en` will be used for looking up translations. -NOTE: The i18n library takes a **pragmatic approach** to locale keys (after [some discussion](http://groups.google.com/group/rails-i18n/browse_thread/thread/14dede2c7dbe9470/80eec34395f64f3c?hl=en)), including only the _locale_ ("language") part, like `:en`, `:pl`, not the _region_ part, like `:en-US` or `:en-GB`, which are traditionally used for separating "languages" and "regional setting" or "dialects". Many international applications use only the "language" element of a locale such as `:cs`, `:th` or `:es` (for Czech, Thai and Spanish). However, there are also regional differences within different language groups that may be important. For instance, in the `:en-US` locale you would have $ as a currency symbol, while in `:en-GB`, you would have £. Nothing stops you from separating regional and other settings in this way: you just have to provide full "English - United Kingdom" locale in a `:en-GB` dictionary. Various [Rails I18n plugins](http://rails-i18n.org/wiki) such as [Globalize3](https://github.com/globalize/globalize) may help you implement it. +NOTE: The i18n library takes a **pragmatic approach** to locale keys (after [some discussion](http://groups.google.com/group/rails-i18n/browse_thread/thread/14dede2c7dbe9470/80eec34395f64f3c?hl=en)), including only the _locale_ ("language") part, like `:en`, `:pl`, not the _region_ part, like `:en-US` or `:en-GB`, which are traditionally used for separating "languages" and "regional setting" or "dialects". Many international applications use only the "language" element of a locale such as `:cs`, `:th` or `:es` (for Czech, Thai and Spanish). However, there are also regional differences within different language groups that may be important. For instance, in the `:en-US` locale you would have $ as a currency symbol, while in `:en-GB`, you would have £. Nothing stops you from separating regional and other settings in this way: you just have to provide full "English - United Kingdom" locale in a `:en-GB` dictionary. Few gems such as [Globalize3](https://github.com/globalize/globalize) may help you implement it. The **translations load path** (`I18n.load_path`) is just a Ruby Array of paths to your translation files that will be loaded automatically and available in your application. You can pick whatever directory and translation file naming scheme makes sense for you. NOTE: The backend will lazy-load these translations when a translation is looked up for the first time. This makes it possible to just swap the backend with something else even after translations have already been announced. -The default `application.rb` files has instructions on how to add locales from another directory and how to set a different default locale. Just uncomment and edit the specific lines. +The default `application.rb` file has instructions on how to add locales from another directory and how to set a different default locale. Just uncomment and edit the specific lines. ```ruby # The default locale is :en and all translations from config/locales/*.rb,yml are auto loaded. @@ -137,7 +139,7 @@ If you want to translate your Rails application to a **single language other tha However, you would probably like to **provide support for more locales** in your application. In such case, you need to set and pass the locale between requests. -WARNING: You may be tempted to store the chosen locale in a _session_ or a <em>cookie</em>. However, **do not do this**. The locale should be transparent and a part of the URL. This way you won't break people's basic assumptions about the web itself: if you send a URL to a friend, they should see the same page and content as you. A fancy word for this would be that you're being [<em>RESTful</em>](http://en.wikipedia.org/wiki/Representational_State_Transfer). Read more about the RESTful approach in [Stefan Tilkov's articles](http://www.infoq.com/articles/rest-introduction). Sometimes there are exceptions to this rule and those are discussed below. +WARNING: You may be tempted to store the chosen locale in a _session_ or a *cookie*. However, **do not do this**. The locale should be transparent and a part of the URL. This way you won't break people's basic assumptions about the web itself: if you send a URL to a friend, they should see the same page and content as you. A fancy word for this would be that you're being [*RESTful*](http://en.wikipedia.org/wiki/Representational_State_Transfer). Read more about the RESTful approach in [Stefan Tilkov's articles](http://www.infoq.com/articles/rest-introduction). Sometimes there are exceptions to this rule and those are discussed below. The _setting part_ is easy. You can set the locale in a `before_action` in the `ApplicationController` like this: @@ -262,7 +264,7 @@ get '/:locale' => 'dashboard#index' Do take special care about the **order of your routes**, so this route declaration does not "eat" other ones. (You may want to add it directly before the `root :to` declaration.) -NOTE: Have a look at two plugins which simplify work with routes in this way: Sven Fuchs's [routing_filter](https://github.com/svenfuchs/routing-filter/tree/master) and Raul Murciano's [translate_routes](https://github.com/raul/translate_routes/tree/master). +NOTE: Have a look at various gems which simplify working with routes: [routing_filter](https://github.com/svenfuchs/routing-filter/tree/master), [rails-translate-routes](https://github.com/francesc/rails-translate-routes), [route_translator](https://github.com/enriclluelles/route_translator). ### Setting the Locale from the Client Supplied Information @@ -288,7 +290,7 @@ private end ``` -Of course, in a production environment you would need much more robust code, and could use a plugin such as Iain Hecker's [http_accept_language](https://github.com/iain/http_accept_language/tree/master) or even Rack middleware such as Ryan Tomayko's [locale](https://github.com/rack/rack-contrib/blob/master/lib/rack/contrib/locale.rb). +Of course, in a production environment you would need much more robust code, and could use a gem such as Iain Hecker's [http_accept_language](https://github.com/iain/http_accept_language/tree/master) or even Rack middleware such as Ryan Tomayko's [locale](https://github.com/rack/rack-contrib/blob/master/lib/rack/contrib/locale.rb). #### Using GeoIP (or Similar) Database @@ -437,11 +439,11 @@ TIP: Right now you might need to add some more date/time formats in order to mak ### Inflection Rules For Other Locales -Rails 4.0 allows you to define inflection rules (such as rules for singularization and pluralization) for locales other than English. In `config/initializers/inflections.rb`, you can define these rules for multiple locales. The initializer contains a default example for specifying additional rules for English; follow that format for other locales as you see fit. +Rails allows you to define inflection rules (such as rules for singularization and pluralization) for locales other than English. In `config/initializers/inflections.rb`, you can define these rules for multiple locales. The initializer contains a default example for specifying additional rules for English; follow that format for other locales as you see fit. ### Localized Views -Rails 2.3 introduces another convenient localization feature: localized views (templates). Let's say you have a _BooksController_ in your application. Your _index_ action renders content in `app/views/books/index.html.erb` template. When you put a _localized variant_ of this template: `index.es.html.erb` in the same directory, Rails will render content in this template, when the locale is set to `:es`. When the locale is set to the default locale, the generic `index.html.erb` view will be used. (Future Rails versions may well bring this _automagic_ localization to assets in `public`, etc.) +Let's say you have a _BooksController_ in your application. Your _index_ action renders content in `app/views/books/index.html.erb` template. When you put a _localized variant_ of this template: `index.es.html.erb` in the same directory, Rails will render content in this template, when the locale is set to `:es`. When the locale is set to the default locale, the generic `index.html.erb` view will be used. (Future Rails versions may well bring this _automagic_ localization to assets in `public`, etc.) You can make use of this feature, e.g. when working with a large amount of static content, which would be clumsy to put inside YAML or Ruby dictionaries. Bear in mind, though, that any change you would like to do later to the template must be propagated to all of them. @@ -484,8 +486,6 @@ NOTE: The default locale loading mechanism in Rails does not load locale files i ``` -Do check the [Rails i18n Wiki](http://rails-i18n.org/wiki) for list of tools available for managing translations. - Overview of the I18n API Features --------------------------------- @@ -530,7 +530,7 @@ Thus the following calls are equivalent: ```ruby I18n.t 'activerecord.errors.messages.record_invalid' -I18n.t 'errors.messages.record_invalid', scope: :active_record +I18n.t 'errors.messages.record_invalid', scope: :activerecord I18n.t :record_invalid, scope: 'activerecord.errors.messages' I18n.t :record_invalid, scope: [:activerecord, :errors, :messages] ``` @@ -588,6 +588,26 @@ you can look up the `books.index.title` value **inside** `app/views/books/index. NOTE: Automatic translation scoping by partial is only available from the `translate` view helper method. +"Lazy" lookup can also be used in controllers: + +```yaml +en: + books: + create: + success: Book created! +``` + +This is useful for setting flash messages for instance: + +```ruby +class BooksController < ApplicationController + def create + # ... + redirect_to books_url, notice: t('.success') + end +end +``` + ### Interpolation In many cases you want to abstract your translations so that **variables can be interpolated into the translation**. For this reason the I18n API provides an interpolation feature. @@ -628,7 +648,7 @@ 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 @@ -676,6 +696,22 @@ en: <div><%= t('title.html') %></div> ``` +Interpolation escapes as needed though. For example, given: + +```yaml +en: + welcome_html: "<b>Welcome %{username}!</b>" +``` + +you can safely pass the username as set by the user: + +```erb +<%# This is safe, it is going to be escaped if needed. %> +<%= t('welcome_html', username: @current_user.username %> +``` + +Safe strings on the other hand are interpolated verbatim. + NOTE: Automatic conversion to HTML safe translate text is only available from the `translate` view helper method.  @@ -793,7 +829,7 @@ So, for example, instead of the default error message `"cannot be blank"` you co | validation | with option | message | interpolation | | ------------ | ------------------------- | ------------------------- | ------------- | -| confirmation | - | :confirmation | - | +| confirmation | - | :confirmation | attribute | | acceptance | - | :accepted | - | | presence | - | :blank | - | | absence | - | :present | - | @@ -813,6 +849,7 @@ So, for example, instead of the default error message `"cannot be blank"` you co | numericality | :equal_to | :equal_to | count | | numericality | :less_than | :less_than | count | | numericality | :less_than_or_equal_to | :less_than_or_equal_to | count | +| numericality | :other_than | :other_than | count | | numericality | :only_integer | :not_an_integer | - | | numericality | :odd | :odd | - | | numericality | :even | :even | - | @@ -860,6 +897,24 @@ en: subject: "Welcome to Rails Guides!" ``` +To send parameters to interpolation use the `default_i18n_subject` method on the mailer. + +```ruby +# user_mailer.rb +class UserMailer < ActionMailer::Base + def welcome(user) + mail(to: user.email, subject: default_i18n_subject(user: user.name)) + end +end +``` + +```yaml +en: + user_mailer: + welcome: + subject: "%{user}, welcome to Rails Guides!" +``` + ### Overview of Other Built-In Methods that Provide I18n Support Rails uses fixed strings and other localizations, such as format strings and other format information in a couple of helpers. Here's a brief overview. @@ -975,7 +1030,7 @@ In other contexts you might want to change this behavior, though. E.g. the defau module I18n class JustRaiseExceptionHandler < ExceptionHandler def call(exception, locale, key, options) - if exception.is_a?(MissingTranslation) + if exception.is_a?(MissingTranslationData) raise exception.to_exception else super @@ -992,7 +1047,7 @@ This would re-raise only the `MissingTranslationData` exception, passing all oth However, if you are using `I18n::Backend::Pluralization` this handler will also raise `I18n::MissingTranslationData: translation missing: en.i18n.plural.rule` exception that should normally be ignored to fall back to the default pluralization rule for English locale. To avoid this you may use additional check for translation key: ```ruby -if exception.is_a?(MissingTranslation) && key.to_s != 'i18n.plural.rule' +if exception.is_a?(MissingTranslationData) && key.to_s != 'i18n.plural.rule' raise exception.to_exception else super @@ -1018,9 +1073,9 @@ If you find anything missing or wrong in this guide, please file a ticket on our Contributing to Rails I18n -------------------------- -I18n support in Ruby on Rails was introduced in the release 2.2 and is still evolving. The project follows the good Ruby on Rails development tradition of evolving solutions in plugins and real applications first, and only then cherry-picking the best-of-breed of most widely useful features for inclusion in the core. +I18n support in Ruby on Rails was introduced in the release 2.2 and is still evolving. The project follows the good Ruby on Rails development tradition of evolving solutions in gems and real applications first, and only then cherry-picking the best-of-breed of most widely useful features for inclusion in the core. -Thus we encourage everybody to experiment with new ideas and features in plugins or other libraries and make them available to the community. (Don't forget to announce your work on our [mailing list](http://groups.google.com/group/rails-i18n!)) +Thus we encourage everybody to experiment with new ideas and features in gems or other libraries and make them available to the community. (Don't forget to announce your work on our [mailing list](http://groups.google.com/group/rails-i18n!)) If you find your own locale (language) missing from our [example translations data](https://github.com/svenfuchs/rails-i18n/tree/master/rails/locale) repository for Ruby on Rails, please [_fork_](https://github.com/guides/fork-a-project-and-submit-your-modifications) the repository, add your data and send a [pull request](https://github.com/guides/pull-requests). @@ -1028,7 +1083,6 @@ If you find your own locale (language) missing from our [example translations da Resources --------- -* [rails-i18n.org](http://rails-i18n.org) - Homepage of the rails-i18n project. You can find lots of useful resources on the [wiki](http://rails-i18n.org/wiki). * [Google group: rails-i18n](http://groups.google.com/group/rails-i18n) - The project's mailing list. * [GitHub: rails-i18n](https://github.com/svenfuchs/rails-i18n/tree/master) - Code repository for the rails-i18n project. Most importantly you can find lots of [example translations](https://github.com/svenfuchs/rails-i18n/tree/master/rails/locale) for Rails that should work for your application in most cases. * [GitHub: i18n](https://github.com/svenfuchs/i18n/tree/master) - Code repository for the i18n gem. |