The Dependency Injection Tags
Edit this pageWarning: You are browsing the documentation for Symfony 2.4, which is no longer maintained.
Read the updated version of this page for Symfony 6.3 (the current stable version).
The Dependency Injection Tags
Dependency Injection Tags are little strings that can be applied to a service
to "flag" it to be used in some special way. For example, if you have a service
that you would like to register as a listener to one of Symfony's core events,
you can flag it with the kernel.event_listener
tag.
You can learn a little bit more about "tags" by reading the "Service Container" section of the Service Container chapter.
Below is information about all of the tags available inside Symfony. There may also be tags in other bundles you use that aren't listed here.
Tag Name | Usage |
---|---|
assetic.asset | Register an asset to the current asset manager |
assetic.factory_worker | Add a factory worker |
assetic.filter | Register a filter |
assetic.formula_loader | Add a formula loader to the current asset manager |
assetic.formula_resource | Adds a resource to the current asset manager |
assetic.templating.php | Remove this service if PHP templating is disabled |
assetic.templating.twig | Remove this service if Twig templating is disabled |
console.command | Add a command |
data_collector | Create a class that collects custom data for the profiler |
doctrine.event_listener | Add a Doctrine event listener |
doctrine.event_subscriber | Add a Doctrine event subscriber |
form.type | Create a custom form field type |
form.type_extension | Create a custom "form extension" |
form.type_guesser | Add your own logic for "form type guessing" |
kernel.cache_clearer | Register your service to be called during the cache clearing process |
kernel.cache_warmer | Register your service to be called during the cache warming process |
kernel.event_listener | Listen to different events/hooks in Symfony |
kernel.event_subscriber | To subscribe to a set of different events/hooks in Symfony |
kernel.fragment_renderer | Add new HTTP content rendering strategies |
monolog.logger | Logging with a custom logging channel |
monolog.processor | Add a custom processor for logging |
routing.loader | Register a custom service that loads routes |
security.voter | Add a custom voter to Symfony's authorization logic |
security.remember_me_aware | To allow remember me authentication |
serializer.encoder | Register a new encoder in the serializer service |
serializer.normalizer | Register a new normalizer in the serializer service |
swiftmailer.default.plugin | Register a custom SwiftMailer Plugin |
templating.helper | Make your service available in PHP templates |
translation.loader | Register a custom service that loads translations |
translation.extractor | Register a custom service that extracts translation messages from a file |
translation.dumper | Register a custom service that dumps translation messages |
twig.extension | Register a custom Twig Extension |
twig.loader | Register a custom service that loads Twig templates |
validator.constraint_validator | Create your own custom validation constraint |
validator.initializer | Register a service that initializes objects before validation |
assetic.asset
Purpose: Register an asset with the current asset manager
assetic.factory_worker
Purpose: Add a factory worker
A Factory worker is a class implementing Assetic\Factory\Worker\WorkerInterface
.
Its process($asset)
method is called for each asset after asset creation.
You can modify an asset or even return a new one.
In order to add a new worker, first create a class:
1 2 3 4 5 6 7 8 9 10 11
use Assetic\Asset\AssetInterface;
use Assetic\Factory\Worker\WorkerInterface;
class MyWorker implements WorkerInterface
{
public function process(AssetInterface $asset)
{
// ... change $asset or return a new one
}
}
And then register it as a tagged service:
1 2 3 4 5
services:
acme.my_worker:
class: MyWorker
tags:
- { name: assetic.factory_worker }
1 2 3 4 5 6 7 8 9 10 11
<?xml version="1.0" encoding="UTF-8" ?>
<container xmlns="http://symfony.com/schema/dic/services"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://symfony.com/schema/dic/services http://symfony.com/schema/dic/services/services-1.0.xsd">
<services>
<service id="acme.my_worker" class="MyWorker>
<tag name="assetic.factory_worker" />
</service>
</services>
</container>
1 2 3 4
$container
->register('acme.my_worker', 'MyWorker')
->addTag('assetic.factory_worker')
;
assetic.filter
Purpose: Register a filter
AsseticBundle uses this tag to register common filters. You can also use this tag to register your own filters.
First, you need to create a filter:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
use Assetic\Asset\AssetInterface;
use Assetic\Filter\FilterInterface;
class MyFilter implements FilterInterface
{
public function filterLoad(AssetInterface $asset)
{
$asset->setContent('alert("yo");' . $asset->getContent());
}
public function filterDump(AssetInterface $asset)
{
// ...
}
}
Second, define a service:
1 2 3 4 5
services:
acme.my_filter:
class: MyFilter
tags:
- { name: assetic.filter, alias: my_filter }
1 2 3 4 5 6 7 8 9 10 11
<?xml version="1.0" encoding="UTF-8" ?>
<container xmlns="http://symfony.com/schema/dic/services"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://symfony.com/schema/dic/services http://symfony.com/schema/dic/services/services-1.0.xsd">
<services>
<service id="acme.my_filter" class="MyFilter">
<tag name="assetic.filter" alias="my_filter" />
</service>
</services>
</container>
1 2 3 4
$container
->register('acme.my_filter', 'MyFilter')
->addTag('assetic.filter', array('alias' => 'my_filter'))
;
Finally, apply the filter:
1 2 3 4 5 6
{% javascripts
'@AcmeBaseBundle/Resources/public/js/global.js'
filter='my_filter'
%}
<script src="{{ asset_url }}"></script>
{% endjavascripts %}
You can also apply your filter via the assetic.filters.my_filter.apply_to
config option as it's described here: How to Apply an Assetic Filter to a specific File Extension.
In order to do that, you must define your filter service in a separate xml
config file and point to this file's path via the assetic.filters.my_filter.resource
configuration key.
assetic.formula_loader
Purpose: Add a formula loader to the current asset manager
A Formula loader is a class implementing
Assetic
interface. This class
is responsible for loading assets from a particular kind of resources (for
instance, twig template). Assetic ships loaders for PHP and Twig templates.
An alias
attribute defines the name of the loader.
assetic.formula_resource
Purpose: Adds a resource to the current asset manager
A resource is something formulae can be loaded from. For instance, Twig templates are resources.
assetic.templating.php
Purpose: Remove this service if PHP templating is disabled
The tagged service will be removed from the container if the
framework.templating.engines
config section does not contain php.
assetic.templating.twig
Purpose: Remove this service if Twig templating is disabled
The tagged service will be removed from the container if
framework.templating.engines
config section does not contain twig
.
console.command
2.4
Support for registering commands in the service container was introduced in Symfony 2.4.
Purpose: Add a command to the application
For details on registering your own commands in the service container, read the cookbook article.
data_collector
Purpose: Create a class that collects custom data for the profiler
For details on creating your own custom data collection, read the cookbook article: How to Create a custom Data Collector.
doctrine.event_listener
Purpose: Add a Doctrine event listener
For details on creating Doctrine event listeners, read the cookbook article: How to Register Event Listeners and Subscribers.
doctrine.event_subscriber
Purpose: Add a Doctrine event subscriber
For details on creating Doctrine event subscribers, read the cookbook article: How to Register Event Listeners and Subscribers.
form.type
Purpose: Create a custom form field type
For details on creating your own custom form type, read the cookbook article: How to Create a Custom Form Field Type.
form.type_extension
Purpose: Create a custom "form extension"
Form type extensions are a way for you took "hook into" the creation of any field in your form. For example, the addition of the CSRF token is done via a form type extension (FormTypeCsrfExtension).
A form type extension can modify any part of any field in your form. To create a form type extension, first create a class that implements the FormTypeExtensionInterface interface. For simplicity, you'll often extend an AbstractTypeExtension class instead of the interface directly:
1 2 3 4 5 6 7 8 9 10
// src/Acme/MainBundle/Form/Type/MyFormTypeExtension.php
namespace Acme\MainBundle\Form\Type;
use Symfony\Component\Form\AbstractTypeExtension;
class MyFormTypeExtension extends AbstractTypeExtension
{
// ... fill in whatever methods you want to override
// like buildForm(), buildView(), finishView(), setDefaultOptions()
}
In order for Symfony to know about your form extension and use it, give it
the form.type_extension
tag:
1 2 3 4 5
services:
main.form.type.my_form_type_extension:
class: Acme\MainBundle\Form\Type\MyFormTypeExtension
tags:
- { name: form.type_extension, alias: field }
1 2 3 4 5 6 7 8 9 10 11 12 13 14
<?xml version="1.0" encoding="UTF-8" ?>
<container xmlns="http://symfony.com/schema/dic/services"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://symfony.com/schema/dic/services http://symfony.com/schema/dic/services/services-1.0.xsd">
<services>
<service
id="main.form.type.my_form_type_extension"
class="Acme\MainBundle\Form\Type\MyFormTypeExtension">
<tag name="form.type_extension" alias="field" />
</service>
</services>
</container>
1 2 3 4
$container
->register('main.form.type.my_form_type_extension', 'Acme\MainBundle\Form\Type\MyFormTypeExtension')
->addTag('form.type_extension', array('alias' => 'field'))
;
The alias
key of the tag is the type of field that this extension should
be applied to. For example, to apply the extension to any form/field, use the
"form" value.
form.type_guesser
Purpose: Add your own logic for "form type guessing"
This tag allows you to add your own logic to the Form Guessing process. By default, form guessing is done by "guessers" based on the validation metadata and Doctrine metadata (if you're using Doctrine) or Propel metadata (if you're using Propel).
See also
For information on how to create your own type guesser, see Creating a custom Type Guesser.
kernel.cache_clearer
Purpose: Register your service to be called during the cache clearing process
Cache clearing occurs whenever you call cache:clear
command. If your
bundle caches files, you should add custom cache clearer for clearing those
files during the cache clearing process.
In order to register your custom cache clearer, first you must create a service class:
1 2 3 4 5 6 7 8 9 10 11 12 13
// src/Acme/MainBundle/Cache/MyClearer.php
namespace Acme\MainBundle\Cache;
use Symfony\Component\HttpKernel\CacheClearer\CacheClearerInterface;
class MyClearer implements CacheClearerInterface
{
public function clear($cacheDir)
{
// clear your cache
}
}
Then register this class and tag it with kernel.cache_clearer
:
1 2 3 4 5
services:
my_cache_clearer:
class: Acme\MainBundle\Cache\MyClearer
tags:
- { name: kernel.cache_clearer }
1 2 3 4 5 6 7 8 9 10 11
<?xml version="1.0" encoding="UTF-8" ?>
<container xmlns="http://symfony.com/schema/dic/services"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://symfony.com/schema/dic/services http://symfony.com/schema/dic/services/services-1.0.xsd">
<services>
<service id="my_cache_clearer" class="Acme\MainBundle\Cache\MyClearer">
<tag name="kernel.cache_clearer" />
</service>
</services>
</container>
1 2 3 4
$container
->register('my_cache_clearer', 'Acme\MainBundle\Cache\MyClearer')
->addTag('kernel.cache_clearer')
;
kernel.cache_warmer
Purpose: Register your service to be called during the cache warming process
Cache warming occurs whenever you run the cache:warmup
or cache:clear
task (unless you pass --no-warmup
to cache:clear
). It is also run when
handling the request, if it wasn't done by one of the commands yet. The purpose is
to initialize any cache that will be needed by the application and prevent
the first user from any significant "cache hit" where the cache is generated
dynamically.
To register your own cache warmer, first create a service that implements the CacheWarmerInterface interface:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17
// src/Acme/MainBundle/Cache/MyCustomWarmer.php
namespace Acme\MainBundle\Cache;
use Symfony\Component\HttpKernel\CacheWarmer\CacheWarmerInterface;
class MyCustomWarmer implements CacheWarmerInterface
{
public function warmUp($cacheDir)
{
// ... do some sort of operations to "warm" your cache
}
public function isOptional()
{
return true;
}
}
The isOptional
method should return true if it's possible to use the
application without calling this cache warmer. In Symfony, optional warmers
are always executed by default (you can change this by using the
--no-optional-warmers
option when executing the command).
To register your warmer with Symfony, give it the kernel.cache_warmer
tag:
1 2 3 4 5
services:
main.warmer.my_custom_warmer:
class: Acme\MainBundle\Cache\MyCustomWarmer
tags:
- { name: kernel.cache_warmer, priority: 0 }
1 2 3 4 5 6 7 8 9 10 11
<?xml version="1.0" encoding="UTF-8" ?>
<container xmlns="http://symfony.com/schema/dic/services"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://symfony.com/schema/dic/services http://symfony.com/schema/dic/services/services-1.0.xsd">
<services>
<service id="main.warmer.my_custom_warmer" class="Acme\MainBundle\Cache\MyCustomWarmer">
<tag name="kernel.cache_warmer" priority="0" />
</service>
</services>
</container>
1 2 3 4
$container
->register('main.warmer.my_custom_warmer', 'Acme\MainBundle\Cache\MyCustomWarmer')
->addTag('kernel.cache_warmer', array('priority' => 0))
;
Note
The priority
value is optional, and defaults to 0.
The higher the priority, the sooner it gets executed.
Core Cache Warmers
Cache Warmer Class Name | Priority |
---|---|
TemplatePathsCacheWarmer | 20 |
RouterCacheWarmer | 0 |
TemplateCacheCacheWarmer | 0 |
kernel.event_listener
Purpose: To listen to different events/hooks in Symfony
This tag allows you to hook your own classes into Symfony's process at different points.
For a full example of this listener, read the How to Create an Event Listener cookbook entry.
For another practical example of a kernel listener, see the cookbook article: How to Register a new Request Format and Mime Type.
Core Event Listener Reference
When adding your own listeners, it might be useful to know about the other core Symfony listeners and their priorities.
Note
All listeners listed here may not be listening depending on your environment, settings and bundles. Additionally, third-party bundles will bring in additional listeners not listed here.
kernel.request
Listener Class Name | Priority |
---|---|
ProfilerListener | 1024 |
TestSessionListener | 192 |
SessionListener | 128 |
RouterListener | 32 |
LocaleListener | 16 |
Firewall | 8 |
kernel.controller
Listener Class Name | Priority |
---|---|
RequestDataCollector | 0 |
kernel.response
Listener Class Name | Priority |
---|---|
EsiListener | 0 |
ResponseListener | 0 |
ResponseListener | 0 |
ProfilerListener | -100 |
TestSessionListener | -128 |
WebDebugToolbarListener | -128 |
StreamedResponseListener | -1024 |
kernel.exception
Listener Class Name | Priority |
---|---|
ProfilerListener | 0 |
ExceptionListener | -128 |
kernel.terminate
Listener Class Name | Priority |
---|---|
EmailSenderListener | 0 |
kernel.event_subscriber
Purpose: To subscribe to a set of different events/hooks in Symfony
To enable a custom subscriber, add it as a regular service in one of your
configuration, and tag it with kernel.event_subscriber
:
1 2 3 4 5
services:
kernel.subscriber.your_subscriber_name:
class: Fully\Qualified\Subscriber\Class\Name
tags:
- { name: kernel.event_subscriber }
1 2 3 4 5 6 7 8 9 10 11 12 13 14
<?xml version="1.0" encoding="UTF-8" ?>
<container xmlns="http://symfony.com/schema/dic/services"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://symfony.com/schema/dic/services http://symfony.com/schema/dic/services/services-1.0.xsd">
<services>
<service
id="kernel.subscriber.your_subscriber_name"
class="Fully\Qualified\Subscriber\Class\Name">
<tag name="kernel.event_subscriber" />
</service>
</services>
</container>
1 2 3 4
$container
->register('kernel.subscriber.your_subscriber_name', 'Fully\Qualified\Subscriber\Class\Name')
->addTag('kernel.event_subscriber')
;
Note
Your service must implement the EventSubscriberInterface interface.
Note
If your service is created by a factory, you MUST correctly set the class
parameter for this tag to work correctly.
kernel.fragment_renderer
Purpose: Add a new HTTP content rendering strategy
To add a new rendering strategy - in addition to the core strategies like
EsiFragmentRenderer
- create a class that implements
FragmentRendererInterface,
register it as a service, then tag it with kernel.fragment_renderer
.
monolog.logger
Purpose: To use a custom logging channel with Monolog
Monolog allows you to share its handlers between several logging channels.
The logger service uses the channel app
but you can change the
channel when injecting the logger in a service.
1 2 3 4 5 6
services:
my_service:
class: Fully\Qualified\Loader\Class\Name
arguments: ["@logger"]
tags:
- { name: monolog.logger, channel: acme }
1 2 3 4 5 6 7 8 9 10 11 12
<?xml version="1.0" encoding="UTF-8" ?>
<container xmlns="http://symfony.com/schema/dic/services"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://symfony.com/schema/dic/services http://symfony.com/schema/dic/services/services-1.0.xsd">
<services>
<service id="my_service" class="Fully\Qualified\Loader\Class\Name">
<argument type="service" id="logger" />
<tag name="monolog.logger" channel="acme" />
</service>
</services>
</container>
1 2 3
$definition = new Definition('Fully\Qualified\Loader\Class\Name', array(new Reference('logger'));
$definition->addTag('monolog.logger', array('channel' => 'acme'));
$container->setDefinition('my_service', $definition);
Tip
If you use MonologBundle 2.4 or higher, you can configure custom channels in the configuration and retrieve the corresponding logger service from the service container directly (see How to Log Messages to different Files).
monolog.processor
Purpose: Add a custom processor for logging
Monolog allows you to add processors in the logger or in the handlers to add
extra data in the records. A processor receives the record as an argument and
must return it after adding some extra data in the extra
attribute of
the record.
The built-in IntrospectionProcessor
can be used to add the file, the line,
the class and the method where the logger was triggered.
You can add a processor globally:
1 2 3 4 5
services:
my_service:
class: Monolog\Processor\IntrospectionProcessor
tags:
- { name: monolog.processor }
1 2 3 4 5 6 7 8 9 10 11
<?xml version="1.0" encoding="UTF-8" ?>
<container xmlns="http://symfony.com/schema/dic/services"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://symfony.com/schema/dic/services http://symfony.com/schema/dic/services/services-1.0.xsd">
<services>
<service id="my_service" class="Monolog\Processor\IntrospectionProcessor">
<tag name="monolog.processor" />
</service>
</services>
</container>
1 2 3 4
$container
->register('my_service', 'Monolog\Processor\IntrospectionProcessor')
->addTag('monolog.processor')
;
Tip
If your service is not a callable (using __invoke
) you can add the
method
attribute in the tag to use a specific method.
You can add also a processor for a specific handler by using the handler
attribute:
1 2 3 4 5
services:
my_service:
class: Monolog\Processor\IntrospectionProcessor
tags:
- { name: monolog.processor, handler: firephp }
1 2 3 4 5 6 7 8 9 10 11
<?xml version="1.0" encoding="UTF-8" ?>
<container xmlns="http://symfony.com/schema/dic/services"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://symfony.com/schema/dic/services http://symfony.com/schema/dic/services/services-1.0.xsd">
<services>
<service id="my_service" class="Monolog\Processor\IntrospectionProcessor">
<tag name="monolog.processor" handler="firephp" />
</service>
</services>
</container>
1 2 3 4
$container
->register('my_service', 'Monolog\Processor\IntrospectionProcessor')
->addTag('monolog.processor', array('handler' => 'firephp'))
;
You can also add a processor for a specific logging channel by using the channel
attribute. This will register the processor only for the security
logging
channel used in the Security component:
1 2 3 4 5
services:
my_service:
class: Monolog\Processor\IntrospectionProcessor
tags:
- { name: monolog.processor, channel: security }
1 2 3 4 5 6 7 8 9 10 11
<?xml version="1.0" encoding="UTF-8" ?>
<container xmlns="http://symfony.com/schema/dic/services"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://symfony.com/schema/dic/services http://symfony.com/schema/dic/services/services-1.0.xsd">
<services>
<service id="my_service" class="Monolog\Processor\IntrospectionProcessor">
<tag name="monolog.processor" channel="security" />
</service>
</services>
</container>
1 2 3 4
$container
->register('my_service', 'Monolog\Processor\IntrospectionProcessor')
->addTag('monolog.processor', array('channel' => 'security'))
;
Note
You cannot use both the handler
and channel
attributes for the
same tag as handlers are shared between all channels.
routing.loader
Purpose: Register a custom service that loads routes
To enable a custom routing loader, add it as a regular service in one
of your configuration, and tag it with routing.loader
:
1 2 3 4 5
services:
routing.loader.your_loader_name:
class: Fully\Qualified\Loader\Class\Name
tags:
- { name: routing.loader }
1 2 3 4 5 6 7 8 9 10 11 12 13 14
<?xml version="1.0" encoding="UTF-8" ?>
<container xmlns="http://symfony.com/schema/dic/services"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://symfony.com/schema/dic/services http://symfony.com/schema/dic/services/services-1.0.xsd">
<services>
<service
id="routing.loader.your_loader_name"
class="Fully\Qualified\Loader\Class\Name">
<tag name="routing.loader" />
</service>
</services>
</container>
1 2 3 4
$container
->register('routing.loader.your_loader_name', 'Fully\Qualified\Loader\Class\Name')
->addTag('routing.loader')
;
For more information, see How to Create a custom Route Loader.
security.remember_me_aware
Purpose: To allow remember me authentication
This tag is used internally to allow remember-me authentication to work. If you have a custom authentication method where a user can be remember-me authenticated, then you may need to use this tag.
If your custom authentication factory extends AbstractFactory and your custom authentication listener extends AbstractAuthenticationListener, then your custom authentication listener will automatically have this tagged applied and it will function automatically.
security.voter
Purpose: To add a custom voter to Symfony's authorization logic
When you call isGranted
on Symfony's security context, a system of "voters"
is used behind the scenes to determine if the user should have access. The
security.voter
tag allows you to add your own custom voter to that system.
For more information, read the cookbook article: How to Implement your own Voter to Blacklist IP Addresses.
serializer.encoder
Purpose: Register a new encoder in the serializer
service
The class that's tagged should implement the EncoderInterface and DecoderInterface.
For more details, see How to Use the Serializer.
serializer.normalizer
Purpose: Register a new normalizer in the Serializer service
The class that's tagged should implement the NormalizerInterface and DenormalizerInterface.
For more details, see How to Use the Serializer.
swiftmailer.default.plugin
Purpose: Register a custom SwiftMailer Plugin
If you're using a custom SwiftMailer plugin (or want to create one), you can
register it with SwiftMailer by creating a service for your plugin and tagging
it with swiftmailer.default.plugin
(it has no options).
Note
default
in this tag is the name of the mailer. If you have multiple
mailers configured or have changed the default mailer name for some reason,
you should change it to the name of your mailer in order to use this tag.
A SwiftMailer plugin must implement the Swift_Events_EventListener
interface.
For more information on plugins, see SwiftMailer's Plugin Documentation.
Several SwiftMailer plugins are core to Symfony and can be activated via different configuration. For details, see SwiftmailerBundle Configuration ("swiftmailer").
templating.helper
Purpose: Make your service available in PHP templates
To enable a custom template helper, add it as a regular service in one
of your configuration, tag it with templating.helper
and define an
alias
attribute (the helper will be accessible via this alias in the
templates):
1 2 3 4 5
services:
templating.helper.your_helper_name:
class: Fully\Qualified\Helper\Class\Name
tags:
- { name: templating.helper, alias: alias_name }
1 2 3 4 5 6 7 8 9 10 11 12 13 14
<?xml version="1.0" encoding="UTF-8" ?>
<container xmlns="http://symfony.com/schema/dic/services"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://symfony.com/schema/dic/services http://symfony.com/schema/dic/services/services-1.0.xsd">
<services>
<service
id="templating.helper.your_helper_name"
class="Fully\Qualified\Helper\Class\Name">
<tag name="templating.helper" alias="alias_name" />
</service>
</services>
</container>
1 2 3 4
$container
->register('templating.helper.your_helper_name', 'Fully\Qualified\Helper\Class\Name')
->addTag('templating.helper', array('alias' => 'alias_name'))
;
translation.loader
Purpose: To register a custom service that loads translations
By default, translations are loaded from the filesystem in a variety of different formats (YAML, XLIFF, PHP, etc).
See also
Learn how to load custom formats in the components section.
Now, register your loader as a service and tag it with translation.loader
:
1 2 3 4 5
services:
main.translation.my_custom_loader:
class: Acme\MainBundle\Translation\MyCustomLoader
tags:
- { name: translation.loader, alias: bin }
1 2 3 4 5 6 7 8 9 10 11 12 13 14
<?xml version="1.0" encoding="UTF-8" ?>
<container xmlns="http://symfony.com/schema/dic/services"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://symfony.com/schema/dic/services http://symfony.com/schema/dic/services/services-1.0.xsd">
<services>
<service
id="main.translation.my_custom_loader"
class="Acme\MainBundle\Translation\MyCustomLoader">
<tag name="translation.loader" alias="bin" />
</service>
</services>
</container>
1 2 3 4
$container
->register('main.translation.my_custom_loader', 'Acme\MainBundle\Translation\MyCustomLoader')
->addTag('translation.loader', array('alias' => 'bin'))
;
The alias
option is required and very important: it defines the file
"suffix" that will be used for the resource files that use this loader. For
example, suppose you have some custom bin
format that you need to load.
If you have a bin
file that contains French translations for the messages
domain, then you might have a file app/Resources/translations/messages.fr.bin
.
When Symfony tries to load the bin
file, it passes the path to your custom
loader as the $resource
argument. You can then perform any logic you need
on that file in order to load your translations.
If you're loading translations from a database, you'll still need a resource
file, but it might either be blank or contain a little bit of information
about loading those resources from the database. The file is key to trigger
the load
method on your custom loader.
translation.extractor
Purpose: To register a custom service that extracts messages from a file
When executing the translation:update
command, it uses extractors to
extract translation messages from a file. By default, the Symfony framework
has a TwigExtractor and a
PhpExtractor, which
help to find and extract translation keys from Twig templates and PHP files.
You can create your own extractor by creating a class that implements
ExtractorInterface and
tagging the service with translation.extractor
. The tag has one required
option: alias
, which defines the name of the extractor:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26
// src/Acme/DemoBundle/Translation/FooExtractor.php
namespace Acme\DemoBundle\Translation;
use Symfony\Component\Translation\Extractor\ExtractorInterface;
use Symfony\Component\Translation\MessageCatalogue;
class FooExtractor implements ExtractorInterface
{
protected $prefix;
/**
* Extracts translation messages from a template directory to the catalogue.
*/
public function extract($directory, MessageCatalogue $catalogue)
{
// ...
}
/**
* Sets the prefix that should be used for new found messages.
*/
public function setPrefix($prefix)
{
$this->prefix = $prefix;
}
}
1 2 3 4 5
services:
acme_demo.translation.extractor.foo:
class: Acme\DemoBundle\Translation\FooExtractor
tags:
- { name: translation.extractor, alias: foo }
1 2 3 4 5 6 7 8 9 10 11 12 13 14
<?xml version="1.0" encoding="UTF-8" ?>
<container xmlns="http://symfony.com/schema/dic/services"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://symfony.com/schema/dic/services http://symfony.com/schema/dic/services/services-1.0.xsd">
<services>
<service
id="acme_demo.translation.extractor.foo"
class="Acme\DemoBundle\Translation\FooExtractor">
<tag name="translation.extractor" alias="foo" />
</service>
</services>
</container>
1 2 3 4 5
$container->register(
'acme_demo.translation.extractor.foo',
'Acme\DemoBundle\Translation\FooExtractor'
)
->addTag('translation.extractor', array('alias' => 'foo'));
translation.dumper
Purpose: To register a custom service that dumps messages to a file
After an Extractor has extracted all messages from the templates, the dumpers are executed to dump the messages to a translation file in a specific format.
Symfony already comes with many dumpers:
- CsvFileDumper
- IcuResFileDumper
- IniFileDumper
- MoFileDumper
- PoFileDumper
- QtFileDumper
- XliffFileDumper
- YamlFileDumper
You can create your own dumper by extending
FileDumper or implementing
DumperInterface and tagging
the service with translation.dumper
. The tag has one option: alias
This is the name that's used to determine which dumper should be used.
1 2 3 4 5
services:
acme_demo.translation.dumper.json:
class: Acme\DemoBundle\Translation\JsonFileDumper
tags:
- { name: translation.dumper, alias: json }
1 2 3 4 5 6 7 8 9 10 11 12 13 14
<?xml version="1.0" encoding="UTF-8" ?>
<container xmlns="http://symfony.com/schema/dic/services"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://symfony.com/schema/dic/services http://symfony.com/schema/dic/services/services-1.0.xsd">
<services>
<service
id="acme_demo.translation.dumper.json"
class="Acme\DemoBundle\Translation\JsonFileDumper">
<tag name="translation.dumper" alias="json" />
</service>
</services>
</container>
1 2 3 4 5
$container->register(
'acme_demo.translation.dumper.json',
'Acme\DemoBundle\Translation\JsonFileDumper'
)
->addTag('translation.dumper', array('alias' => 'json'));
See also
Learn how to dump to custom formats in the components section.
twig.extension
Purpose: To register a custom Twig Extension
To enable a Twig extension, add it as a regular service in one of your
configuration, and tag it with twig.extension
:
1 2 3 4 5
services:
twig.extension.your_extension_name:
class: Fully\Qualified\Extension\Class\Name
tags:
- { name: twig.extension }
1 2 3 4 5 6 7 8 9 10 11 12 13 14
<?xml version="1.0" encoding="UTF-8" ?>
<container xmlns="http://symfony.com/schema/dic/services"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://symfony.com/schema/dic/services http://symfony.com/schema/dic/services/services-1.0.xsd">
<services>
<service
id="twig.extension.your_extension_name"
class="Fully\Qualified\Extension\Class\Name">
<tag name="twig.extension" />
</service>
</services>
</container>
1 2 3 4
$container
->register('twig.extension.your_extension_name', 'Fully\Qualified\Extension\Class\Name')
->addTag('twig.extension')
;
For information on how to create the actual Twig Extension class, see Twig's documentation on the topic or read the cookbook article: How to Write a custom Twig Extension.
Before writing your own extensions, have a look at the
Twig official extension repository which already includes several
useful extensions. For example Intl
and its localizeddate
filter
that formats a date according to user's locale. These official Twig extensions
also have to be added as regular services:
1 2 3 4 5
services:
twig.extension.intl:
class: Twig_Extensions_Extension_Intl
tags:
- { name: twig.extension }
1 2 3 4 5 6 7 8 9 10 11
<?xml version="1.0" encoding="UTF-8" ?>
<container xmlns="http://symfony.com/schema/dic/services"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://symfony.com/schema/dic/services http://symfony.com/schema/dic/services/services-1.0.xsd">
<services>
<service id="twig.extension.intl" class="Twig_Extensions_Extension_Intl">
<tag name="twig.extension" />
</service>
</services>
</container>
1 2 3 4
$container
->register('twig.extension.intl', 'Twig_Extensions_Extension_Intl')
->addTag('twig.extension')
;
twig.loader
Purpose: Register a custom service that loads Twig templates
By default, Symfony uses only one Twig Loader -
FilesystemLoader. If you need
to load Twig templates from another resource, you can create a service for
the new loader and tag it with twig.loader
:
1 2 3 4 5
services:
acme.demo_bundle.loader.some_twig_loader:
class: Acme\DemoBundle\Loader\SomeTwigLoader
tags:
- { name: twig.loader }
1 2 3 4 5 6 7 8 9 10 11 12 13 14
<?xml version="1.0" encoding="UTF-8" ?>
<container xmlns="http://symfony.com/schema/dic/services"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://symfony.com/schema/dic/services http://symfony.com/schema/dic/services/services-1.0.xsd">
<services>
<service
id="acme.demo_bundle.loader.some_twig_loader"
class="Acme\DemoBundle\Loader\SomeTwigLoader">
<tag name="twig.loader" />
</service>
</services>
</container>
1 2 3 4
$container
->register('acme.demo_bundle.loader.some_twig_loader', 'Acme\DemoBundle\Loader\SomeTwigLoader')
->addTag('twig.loader')
;
validator.constraint_validator
Purpose: Create your own custom validation constraint
This tag allows you to create and register your own custom validation constraint. For more information, read the cookbook article: How to Create a custom Validation Constraint.
validator.initializer
Purpose: Register a service that initializes objects before validation
This tag provides a very uncommon piece of functionality that allows you to perform some sort of action on an object right before it's validated. For example, it's used by Doctrine to query for all of the lazily-loaded data on an object before it's validated. Without this, some data on a Doctrine entity would appear to be "missing" when validated, even though this is not really the case.
If you do need to use this tag, just make a new class that implements the
ObjectInitializerInterface interface.
Then, tag it with the validator.initializer
tag (it has no options).
For an example, see the EntityInitializer
class inside the Doctrine Bridge.