.. index:: single: Serializer
Symfony provides a serializer to serialize/deserialize to and from objects and different formats (e.g. JSON or XML). Before using it, read the :doc:`Serializer component docs </components/serializer>` to get familiar with its philosophy and the normalizers and encoders terminology.
In applications using :doc:`Symfony Flex </setup/flex>`, run this command to install the serializer before using it:
$ composer require serializer
Once enabled, the serializer service can be injected in any service where you need it or it can be used in a controller:
// src/Controller/DefaultController.php namespace App\Controller; use Symfony\Bundle\FrameworkBundle\Controller\Controller; use Symfony\Component\Serializer\SerializerInterface; class DefaultController extends Controller { public function indexAction(SerializerInterface $serializer) { // keep reading for usage examples } }
Once enabled, the serializer
service will be available in the container.
It comes with a set of useful :ref:`encoders <component-serializer-encoders>`
and :ref:`normalizers <component-serializer-normalizers>`.
Encoders supporting the following formats are enabled:
- JSON: :class:`Symfony\\Component\\Serializer\\Encoder\\JsonEncoder`
- XML: :class:`Symfony\\Component\\Serializer\\Encoder\\XmlEncoder`
As well as the following normalizers:
- :class:`Symfony\\Component\\Serializer\\Normalizer\\ObjectNormalizer` to handle typical data objects
- :class:`Symfony\\Component\\Serializer\\Normalizer\\DateTimeNormalizer` for objects implementing the :class:`DateTimeInterface` interface
- :class:`Symfony\\Component\\Serializer\\Normalizer\\DataUriNormalizer` to transform :class:`SplFileInfo` objects in Data URIs
- :class:`Symfony\\Component\\Serializer\\Normalizer\\JsonSerializableNormalizer` to deal with objects implementing the :class:`JsonSerializable` interface
- :class:`Symfony\\Component\\Serializer\\Normalizer\\ArrayDenormalizer` to denormalize arrays of objects using a format like MyObject[] (note the [] suffix)
Custom normalizers and/or encoders can also be loaded by tagging them as :ref:`serializer.normalizer <reference-dic-tags-serializer-normalizer>` and :ref:`serializer.encoder <reference-dic-tags-serializer-encoder>`. It's also possible to set the priority of the tag in order to decide the matching order.
Here is an example on how to load the :class:`Symfony\\Component\\Serializer\\Normalizer\\GetSetMethodNormalizer`, a faster alternative to the ObjectNormalizer when data objects always use getters and setters:
.. configuration-block:: .. code-block:: yaml # config/services.yaml services: get_set_method_normalizer: class: Symfony\Component\Serializer\Normalizer\GetSetMethodNormalizer public: false tags: [serializer.normalizer] .. code-block:: xml <!-- config/services.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" xsi:schemaLocation="http://symfony.com/schema/dic/services http://symfony.com/schema/dic/services/services-1.0.xsd"> <services> <service id="get_set_method_normalizer" class="Symfony\Component\Serializer\Normalizer\GetSetMethodNormalizer" public="false"> <tag name="serializer.normalizer" /> </service> </services> </container> .. code-block:: php // config/services.php use Symfony\Component\Serializer\Normalizer\GetSetMethodNormalizer; $container->register('get_set_method_normalizer', GetSetMethodNormalizer::class) ->setPublic(false) ->addTag('serializer.normalizer') ;
To use annotations, first install the annotations package:
$ composer require annotations
Next, add the :ref:`@Groups annotations <component-serializer-attributes-groups-annotations>` to your class and choose which groups to use when serializing:
$json = $serializer->serialize( $someObject, 'json', array('groups' => array('group1')) );
In addition to the @Groups
annotation, the Serializer component also
supports YAML or XML files. These files are automatically loaded when being
stored in one of the following locations:
- The
serialization.yaml
orserialization.xml
file in theResources/config/
directory of a bundle; - All
*.yaml
and*.xml
files in theResources/config/serialization/
directory of a bundle.
The metadata for the serializer is automatically cached. To configure the cache,
configure the framework.cache.pools
key in config/packages/framework.yaml
.
The use of a :ref:`name converter <component-serializer-converting-property-names-when-serializing-and-deserializing>` service can be defined in the configuration using the :ref:`name_converter <reference-serializer-name_converter>` option.
The built-in :ref:`CamelCase to snake_case name converter <using-camelized-method-names-for-underscored-attributes>`
can be enabled by using the serializer.name_converter.camel_case_to_snake_case
value:
.. configuration-block:: .. code-block:: yaml # config/packages/framework.yaml framework: # ... serializer: name_converter: 'serializer.name_converter.camel_case_to_snake_case' .. code-block:: xml <!-- config/packages/framework.xml --> <framework:config> <!-- ... --> <framework:serializer name-converter="serializer.name_converter.camel_case_to_snake_case" /> </framework:config> .. code-block:: php // config/packages/framework.php $container->loadFromExtension('framework', array( // ... 'serializer' => array( 'name_converter' => 'serializer.name_converter.camel_case_to_snake_case', ), ));
ApiPlatform provides an API system supporting JSON-LD and Hydra Core Vocabulary hypermedia formats. It is built on top of the Symfony Framework and its Serializer component. It provides custom normalizers and a custom encoder, custom metadata and a caching system.
If you want to leverage the full power of the Symfony Serializer component, take a look at how this bundle works.
.. toctree:: :maxdepth: 1 serializer/encoders serializer/custom_encoders