Mapping fields in Doctrine ORM using Symfony Serializer

This is a proof of concept for a mapping fields with Doctrine ORM so they can be serialized with the Symfony Serializer component, without the need to create a mapping type for each possible data type.

Sometimes you just need to store a complex data type (generally a Value Object) in a JSON field and not worry about database schemas, extra columns or tables, Doctrine embeddables, custom mappings.

Installation

This library requires PHP 8.0 or later.

composer require edudobay/doctrine-symfony-serializer

Usage

See the examples directory for a working code example.

Abridged example

Add this to your application setup:

use Edudobay\DoctrineSerializable\ReflectionClassMetadataFactory;
use Edudobay\DoctrineSerializable\SerializationHandler;
use Edudobay\DoctrineSerializable\PersistenceEventSubscriber;

$serializer = ...; // Symfony Serializer
$entityManager = ...; // Doctrine ORM EntityManager

$subscriber = new PersistenceEventSubscriber(new SerializationHandler(
    $serializer,
    // You might want to cache this. See Psr6CacheClassMetadataFactory
    new ReflectionClassMetadataFactory()
));

$entityManager->getEventManager()->addEventSubscriber($subscriber);

In your entities, have your domain object as you like, and introduce a private backing field that will make it persistent:

use Doctrine\ORM\Mapping as ORM;
use Edudobay\DoctrineSerializable\Attributes\Serializable;

#[ORM\Entity]
class User
{
    // Backing field
    #[ORM\Column('address', type: 'json')]
    private array $_address = [];
    // The actual domain object
    #[Serializable]
    public Address $address;

    // For arrays:
    #[ORM\Column('badges', type: 'json')]
    private array $_badges = [];

    #[Serializable]
    /** @var Badge[] */
    public array $badges;

    // OPTIONAL: use arrayItemType instead of docblock array types
    #[Serializable(arrayItemType: Badge::class)]
    public array $badges;
}