.. index:: single: Translations
The term "internationalization" (often abbreviated i18n) refers to the process of abstracting strings and other locale-specific pieces out of your application into a layer where they can be translated and converted based on the user's locale (i.e. language and country). For text, this means wrapping each with a function capable of translating the text (or "message") into the language of the user:
// text will *always* print out in English
echo 'Hello World';
// text can be translated into the end-user's language or
// default to English
echo $translator->trans('Hello World');
Note
The term locale refers roughly to the user's language and country. It
can be any string that your application uses to manage translations and
other format differences (e.g. currency format). The ISO 639-1
language code, an underscore (_), then the ISO 3166-1 alpha-2
country code (e.g. fr_FR for French/France) is recommended.
In this chapter, you'll learn how to use the Translation component in the Symfony framework. You can read the :doc:`Translation component documentation </components/translation/usage>` to learn even more. Overall, the process has several steps:
- :ref:`Enable and configure <book-translation-configuration>` Symfony's translation service;
- Abstract strings (i.e. "messages") by wrapping them in calls to the
Translator(":ref:`book-translation-basic`"); - :ref:`Create translation resources/files <book-translation-resources>` for each supported locale that translate each message in the application;
- Determine, :ref:`set and manage the user's locale <book-translation-user-locale>` for the request and optionally :doc:`on the user's entire session </cookbook/session/locale_sticky_session>`.
Translations are handled by a translator :term:`service` that uses the
user's locale to lookup and return translated messages. Before using it,
enable the translator in your configuration:
.. configuration-block::
.. code-block:: yaml
# app/config/config.yml
framework:
translator: { fallback: en }
.. code-block:: xml
<!-- app/config/config.xml -->
<?xml version="1.0" encoding="UTF-8" ?>
<container xmlns="http://symfony.com/schema/dic/services"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:framework="http://symfony.com/schema/dic/symfony"
xsi:schemaLocation="http://symfony.com/schema/dic/services
http://symfony.com/schema/dic/services/services-1.0.xsd
http://symfony.com/schema/dic/symfony
http://symfony.com/schema/dic/symfony/symfony-1.0.xsd">
<framework:config>
<framework:translator fallback="en" />
</framework:config>
</container>
.. code-block:: php
// app/config/config.php
$container->loadFromExtension('framework', array(
'translator' => array('fallback' => 'en'),
));
See :ref:`book-translation-fallback` for details on the fallback key
and what Symfony does when it doesn't find a translation.
The locale used in translations is the one stored on the request. This is
typically set via a _locale attribute on your routes (see :ref:`book-translation-locale-url`).
Translation of text is done through the translator service
(:class:`Symfony\\Component\\Translation\\Translator`). To translate a block
of text (called a message), use the
:method:`Symfony\\Component\\Translation\\Translator::trans` method. Suppose,
for example, that you're translating a simple message from inside a controller:
// ...
use Symfony\Component\HttpFoundation\Response;
public function indexAction()
{
$translated = $this->get('translator')->trans('Symfony is great');
return new Response($translated);
}
When this code is executed, Symfony will attempt to translate the message
"Symfony is great" based on the locale of the user. For this to work,
you need to tell Symfony how to translate the message via a "translation
resource", which is usually a file that contains a collection of translations
for a given locale. This "dictionary" of translations can be created in several
different formats, XLIFF being the recommended format:
.. configuration-block::
.. code-block:: xml
<!-- messages.fr.xliff -->
<?xml version="1.0"?>
<xliff version="1.2" xmlns="urn:oasis:names:tc:xliff:document:1.2">
<file source-language="en" datatype="plaintext" original="file.ext">
<body>
<trans-unit id="1">
<source>Symfony is great</source>
<target>J'aime Symfony</target>
</trans-unit>
</body>
</file>
</xliff>
.. code-block:: yaml
# messages.fr.yml
Symfony is great: J'aime Symfony
.. code-block:: php
// messages.fr.php
return array(
'Symfony is great' => 'J\'aime Symfony',
);
For information on where these files should be located, see :ref:`book-translation-resource-locations`.
Now, if the language of the user's locale is French (e.g. fr_FR or fr_BE),
the message will be translated into J'aime Symfony. You can also translate
the message inside your :ref:`templates <book-translation-tags>`.
To actually translate the message, Symfony uses a simple process:
- The
localeof the current user, which is stored on the request is determined; - A catalog (e.g. big collection) of translated messages is loaded from translation
resources defined for the
locale(e.g.fr_FR). Messages from the :ref:`fallback locale <book-translation-fallback>` are also loaded and added to the catalog if they don't already exist. The end result is a large "dictionary" of translations. - If the message is located in the catalog, the translation is returned. If not, the translator returns the original message.
When using the trans() method, Symfony looks for the exact string inside
the appropriate message catalog and returns it (if it exists).
Sometimes, a message containing a variable needs to be translated:
use Symfony\Component\HttpFoundation\Response;
public function indexAction($name)
{
$translated = $this->get('translator')->trans('Hello '.$name);
return new Response($translated);
}
However, creating a translation for this string is impossible since the translator will try to look up the exact message, including the variable portions (e.g. "Hello Ryan" or "Hello Fabien").
For details on how to handle this situation, see :ref:`component-translation-placeholders` in the components documentation. For how to do this in templates, see :ref:`book-translation-tags`.
Another complication is when you have translations that may or may not be plural, based on some variable:
There is one apple.
There are 5 apples.
To handle this, use the :method:`Symfony\\Component\\Translation\\Translator::transChoice`
method or the transchoice tag/filter in your :ref:`template <book-translation-tags>`.
For much more information, see :ref:`component-translation-pluralization` in the Translation component documentation.
Most of the time, translation occurs in templates. Symfony provides native support for both Twig and PHP templates.
Symfony provides specialized Twig tags (trans and transchoice) to
help with message translation of static blocks of text:
{% trans %}Hello %name%{% endtrans %}
{% transchoice count %}
{0} There are no apples|{1} There is one apple|]1,Inf] There are %count% apples
{% endtranschoice %}The transchoice tag automatically gets the %count% variable from
the current context and passes it to the translator. This mechanism only
works when you use a placeholder following the %var% pattern.
Caution!
The %var% notation of placeholders is required when translating in
Twig templates using the tag.
Tip
If you need to use the percent character (%) in a string, escape it by
doubling it: {% trans %}Percent: %percent%%%{% endtrans %}
You can also specify the message domain and pass some additional variables:
{% trans with {'%name%': 'Fabien'} from "app" %}Hello %name%{% endtrans %}
{% trans with {'%name%': 'Fabien'} from "app" into "fr" %}Hello %name%{% endtrans %}
{% transchoice count with {'%name%': 'Fabien'} from "app" %}
{0} %name%, there are no apples|{1} %name%, there is one apple|]1,Inf] %name%, there are %count% apples
{% endtranschoice %}The trans and transchoice filters can be used to translate variable
texts and complex expressions:
{{ message|trans }}
{{ message|transchoice(5) }}
{{ message|trans({'%name%': 'Fabien'}, "app") }}
{{ message|transchoice(5, {'%name%': 'Fabien'}, 'app') }}Tip
Using the translation tags or filters have the same effect, but with
one subtle difference: automatic output escaping is only applied to
translations using a filter. In other words, if you need to be sure
that your translated message is not output escaped, you must apply
the raw filter after the translation filter:
{# text translated between tags is never escaped #}
{% trans %}
<h3>foo</h3>
{% endtrans %}
{% set message = '<h3>foo</h3>' %}
{# strings and variables translated via a filter are escaped by default #}
{{ message|trans|raw }}
{{ '<h3>bar</h3>'|trans|raw }}Tip
You can set the translation domain for an entire Twig template with a single tag:
{% trans_default_domain "app" %}Note that this only influences the current template, not any "included" template (in order to avoid side effects).
The translator service is accessible in PHP templates through the
translator helper:
<?php echo $view['translator']->trans('Symfony is great') ?>
<?php echo $view['translator']->transChoice(
'{0} There are no apples|{1} There is one apple|]1,Inf[ There are %count% apples',
10,
array('%count%' => 10)
) ?>Symfony looks for message files (i.e. translations) in the following locations:
- the
app/Resources/translationsdirectory; - the
app/Resources/<bundle name>/translationsdirectory; - the
Resources/translations/directory inside of any bundle.
The locations are listed here with the highest priority first. That is, you can override the translation messages of a bundle in any of the top 2 directories.
The override mechanism works at a key level: only the overridden keys need to be listed in a higher priority message file. When a key is not found in a message file, the translator will automatically fall back to the lower priority message files.
The filename of the translation files is also important: each message file
must be named according to the following path: domain.locale.loader:
- domain: An optional way to organize messages into groups (e.g.
admin,navigationor the defaultmessages) - see :ref:`using-message-domains`; - locale: The locale that the translations are for (e.g.
en_GB,en, etc); - loader: How Symfony should load and parse the file (e.g.
xliff,php,yml, etc).
The loader can be the name of any registered loader. By default, Symfony provides many loaders, including:
xliff: XLIFF file;php: PHP file;yml: YAML file.
The choice of which loader to use is entirely up to you and is a matter of
taste. The recommended option is to use xliff for translations.
For more options, see :ref:`component-translator-message-catalogs`.
Note
You can also store translations in a database, or any other storage by providing a custom class implementing the :class:`Symfony\\Component\\Translation\\Loader\\LoaderInterface` interface. See the :ref:`dic-tags-translation-loader` tag for more information.
Caution!
Each time you create a new translation resource (or install a bundle that includes a translation resource), be sure to clear your cache so that Symfony can discover the new translation resources:
$ php app/console cache:clearImagine that the user's locale is fr_FR and that you're translating the
key Symfony is great. To find the French translation, Symfony actually
checks translation resources for several locales:
- First, Symfony looks for the translation in a
fr_FRtranslation resource (e.g.messages.fr_FR.xliff); - If it wasn't found, Symfony looks for the translation in a
frtranslation resource (e.g.messages.fr.xliff); - If the translation still isn't found, Symfony uses the
fallbackconfiguration parameter, which defaults toen(see Configuration).
.. versionadded:: 2.6
The ability to log missing translations was introduced in Symfony 2.6.
Note
When Symfony doesn't find a translation in the given locale, it will add the missing translation to the log file. For details, see :ref:`reference-framework-translator-logging`.
The locale of the current user is stored in the request and is accessible
via the request object:
use Symfony\Component\HttpFoundation\Request;
public function indexAction(Request $request)
{
$locale = $request->getLocale();
$request->setLocale('en_US');
}
Tip
Read :doc:`/cookbook/session/locale_sticky_session` to learn how to store the user's locale in the session.
.. index:: single: Translations; Fallback and default locale
See the :ref:`book-translation-locale-url` section below about setting the locale via routing.
Since you can store the locale of the user in the session, it may be tempting
to use the same URL to display a resource in different languages based
on the user's locale. For example, http://www.example.com/contact could
show content in English for one user and French for another user. Unfortunately,
this violates a fundamental rule of the Web: that a particular URL returns
the same resource regardless of the user. To further muddy the problem, which
version of the content would be indexed by search engines?
A better policy is to include the locale in the URL. This is fully-supported
by the routing system using the special _locale parameter:
.. configuration-block::
.. code-block:: yaml
# app/config/routing.yml
contact:
path: /{_locale}/contact
defaults: { _controller: AppBundle:Contact:index }
requirements:
_locale: en|fr|de
.. code-block:: xml
<!-- app/config/routing.xml -->
<?xml version="1.0" encoding="UTF-8" ?>
<routes xmlns="http://symfony.com/schema/routing"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://symfony.com/schema/routing
http://symfony.com/schema/routing/routing-1.0.xsd">
<route id="contact" path="/{_locale}/contact">
<default key="_controller">AppBundle:Contact:index</default>
<requirement key="_locale">en|fr|de</requirement>
</route>
</routes>
.. code-block:: php
// app/config/routing.php
use Symfony\Component\Routing\RouteCollection;
use Symfony\Component\Routing\Route;
$collection = new RouteCollection();
$collection->add('contact', new Route(
'/{_locale}/contact',
array(
'_controller' => 'AppBundle:Contact:index',
),
array(
'_locale' => 'en|fr|de',
)
));
return $collection;
When using the special _locale parameter in a route, the matched locale
will automatically be set on the Request and can be retrieved via the
:method:`Symfony\\Component\\HttpFoundation\\Request::getLocale` method.
In other words, if a user
visits the URI /fr/contact, the locale fr will automatically be set
as the locale for the current request.
You can now use the locale to create routes to other translated pages in your application.
Tip
Read :doc:`/cookbook/routing/service_container_parameters` to learn how to
avoid hardcoding the _locale requirement in all your routes.
What if the user's locale hasn't been determined? You can guarantee that a
locale is set on each user's request by defining a default_locale for
the framework:
.. configuration-block::
.. code-block:: yaml
# app/config/config.yml
framework:
default_locale: en
.. code-block:: xml
<!-- app/config/config.xml -->
<?xml version="1.0" encoding="UTF-8" ?>
<container xmlns="http://symfony.com/schema/dic/services"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:framework="http://symfony.com/schema/dic/symfony"
xsi:schemaLocation="http://symfony.com/schema/dic/services
http://symfony.com/schema/dic/services/services-1.0.xsd
http://symfony.com/schema/dic/symfony
http://symfony.com/schema/dic/symfony/symfony-1.0.xsd">
<framework:config default-locale="en" />
</container>
.. code-block:: php
// app/config/config.php
$container->loadFromExtension('framework', array(
'default_locale' => 'en',
));
If you're using validation constraints with the form framework, then translating
the error messages is easy: simply create a translation resource for the
validators :ref:`domain <using-message-domains>`.
To start, suppose you've created a plain-old-PHP object that you need to use somewhere in your application:
// src/AppBundle/Entity/Author.php
namespace AppBundle\Entity;
class Author
{
public $name;
}
Add constraints though any of the supported methods. Set the message option to the
translation source text. For example, to guarantee that the $name property is
not empty, add the following:
.. configuration-block::
.. code-block:: php-annotations
// src/AppBundle/Entity/Author.php
use Symfony\Component\Validator\Constraints as Assert;
class Author
{
/**
* @Assert\NotBlank(message = "author.name.not_blank")
*/
public $name;
}
.. code-block:: yaml
# src/AppBundle/Resources/config/validation.yml
AppBundle\Entity\Author:
properties:
name:
- NotBlank: { message: "author.name.not_blank" }
.. code-block:: xml
<!-- src/AppBundle/Resources/config/validation.xml -->
<?xml version="1.0" encoding="UTF-8" ?>
<constraint-mapping xmlns="http://symfony.com/schema/dic/constraint-mapping"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://symfony.com/schema/dic/constraint-mapping
http://symfony.com/schema/dic/constraint-mapping/constraint-mapping-1.0.xsd">
<class name="AppBundle\Entity\Author">
<property name="name">
<constraint name="NotBlank">
<option name="message">author.name.not_blank</option>
</constraint>
</property>
</class>
</constraint-mapping>
.. code-block:: php
// src/AppBundle/Entity/Author.php
// ...
use Symfony\Component\Validator\Mapping\ClassMetadata;
use Symfony\Component\Validator\Constraints\NotBlank;
class Author
{
public $name;
public static function loadValidatorMetadata(ClassMetadata $metadata)
{
$metadata->addPropertyConstraint('name', new NotBlank(array(
'message' => 'author.name.not_blank',
)));
}
}
Create a translation file under the validators catalog for the constraint
messages, typically in the Resources/translations/ directory of the
bundle.
.. configuration-block::
.. code-block:: xml
<!-- validators.en.xliff -->
<?xml version="1.0"?>
<xliff version="1.2" xmlns="urn:oasis:names:tc:xliff:document:1.2">
<file source-language="en" datatype="plaintext" original="file.ext">
<body>
<trans-unit id="1">
<source>author.name.not_blank</source>
<target>Please enter an author name.</target>
</trans-unit>
</body>
</file>
</xliff>
.. code-block:: yaml
# validators.en.yml
author.name.not_blank: Please enter an author name.
.. code-block:: php
// validators.en.php
return array(
'author.name.not_blank' => 'Please enter an author name.',
);
The translation of database content should be handled by Doctrine through the Translatable Extension or the Translatable Behavior. For more information, see the documentation for these libraries.
.. versionadded:: 2.6
Prior to Symfony 2.6, this command was called ``translation:debug``.
When maintaining a bundle, you may use or remove the usage of a translation
message without updating all message catalogues. The debug:translation
command helps you to find these missing or unused translation messages for a
given locale. It shows you a table with the result when translating the
message in the given locale and the result when the fallback would be used.
On top of that, it also shows you when the translation is the same as the
fallback translation (this could indicate that the message was not correctly
translated).
Thanks to the messages extractors, the command will detect the translation tag or filter usages in Twig templates:
{% trans %}Symfony2 is great{% endtrans %}
{{ 'Symfony2 is great'|trans }}
{{ 'Symfony2 is great'|transchoice(1) }}
{% transchoice 1 %}Symfony2 is great{% endtranschoice %}It will also detect the following translator usages in PHP templates:
$view['translator']->trans("Symfony2 is great");
$view['translator']->transChoice('Symfony2 is great', 1);Caution!
The extractors are not able to inspect the messages translated outside templates which means that translator usages in form labels or inside your controllers won't be detected. Dynamic translations involving variables or expressions are not detected in templates, which means this example won't be analyzed:
{% set message = 'Symfony2 is great' %}
{{ message|trans }}Suppose your application's default_locale is fr and you have configured en as the fallback locale
(see :ref:`book-translation-configuration` and :ref:`book-translation-fallback` for how to configure these).
And suppose you've already setup some translations for the fr locale inside an AcmeDemoBundle:
.. configuration-block::
.. code-block:: xml
<!-- src/Acme/AcmeDemoBundle/Resources/translations/messages.fr.xliff -->
<?xml version="1.0"?>
<xliff version="1.2" xmlns="urn:oasis:names:tc:xliff:document:1.2">
<file source-language="en" datatype="plaintext" original="file.ext">
<body>
<trans-unit id="1">
<source>Symfony2 is great</source>
<target>J'aime Symfony2</target>
</trans-unit>
</body>
</file>
</xliff>
.. code-block:: yaml
# src/Acme/AcmeDemoBundle/Resources/translations/messages.fr.yml
Symfony2 is great: J'aime Symfony2
.. code-block:: php
// src/Acme/AcmeDemoBundle/Resources/translations/messages.fr.php
return array(
'Symfony2 is great' => 'J\'aime Symfony2',
);
and for the en locale:
.. configuration-block::
.. code-block:: xml
<!-- src/Acme/AcmeDemoBundle/Resources/translations/messages.en.xliff -->
<?xml version="1.0"?>
<xliff version="1.2" xmlns="urn:oasis:names:tc:xliff:document:1.2">
<file source-language="en" datatype="plaintext" original="file.ext">
<body>
<trans-unit id="1">
<source>Symfony2 is great</source>
<target>Symfony2 is great</target>
</trans-unit>
</body>
</file>
</xliff>
.. code-block:: yaml
# src/Acme/AcmeDemoBundle/Resources/translations/messages.en.yml
Symfony2 is great: Symfony2 is great
.. code-block:: php
// src/Acme/AcmeDemoBundle/Resources/translations/messages.en.php
return array(
'Symfony2 is great' => 'Symfony2 is great',
);
To inspect all messages in the fr locale for the AcmeDemoBundle, run:
$ php app/console debug:translation fr AcmeDemoBundleYou will get this output:
It indicates that the message Symfony2 is great is unused because it is translated,
but you haven't used it anywhere yet.
Now, if you translate the message in one of your templates, you will get this output:
The state is empty which means the message is translated in the fr locale and used in one or more templates.
If you delete the message Symfony2 is great from your translation file for the fr locale
and run the command, you will get:
The state indicates the message is missing because it is not translated in the fr locale
but it is still used in the template.
Moreover, the message in the fr locale equals to the message in the en locale.
This is a special case because the untranslated message id equals its translation in the en locale.
If you copy the content of the translation file in the en locale, to the translation file
in the fr locale and run the command, you will get:
You can see that the translations of the message are identical in the fr and en locales
which means this message was probably copied from French to English and maybe you forgot to translate it.
By default all domains are inspected, but it is possible to specify a single domain:
$ php app/console debug:translation en AcmeDemoBundle --domain=messagesWhen bundles have a lot of messages, it is useful to display only the unused
or only the missing messages, by using the --only-unused or --only-missing switches:
$ php app/console debug:translation en AcmeDemoBundle --only-unused
$ php app/console debug:translation en AcmeDemoBundle --only-missingWith the Symfony Translation component, creating an internationalized application no longer needs to be a painful process and boils down to just a few basic steps:
- Abstract messages in your application by wrapping each in either the :method:`Symfony\\Component\\Translation\\Translator::trans` or :method:`Symfony\\Component\\Translation\\Translator::transChoice` methods (learn about this in :doc:`/components/translation/usage`);
- Translate each message into multiple locales by creating translation message files. Symfony discovers and processes each file because its name follows a specific convention;
- Manage the user's locale, which is stored on the request, but can also be set on the user's session.