Doctrine: nullable embeddable

This listener enables you to have truly null values for your Doctrine embeddables. The listener hooks into the postLoad lifecycle callback and replaces embeddable values that are null.

It implements a workaround for this open issue:

• doctrine/orm#4568
• doctrine/orm#1275

Configuration

There are two things you have to do, in order to have this listener working correctly.

1. An entry to the property map has to be made. This is done by calling the \Tarifhaus\Doctrine\ORM\NullableEmbeddableListener::addMapping. It receives the FQCN (fully qualified class name) of the entity and the name of the property path the embeddable resides in.

   For example:

   <?php
   
   use Symfony\Component\PropertyAccess\PropertyAccessor;
   use Tarifhaus\Doctrine\ORM\NullableEmbeddableListener;
   
   $listener = new NullableEmbeddableListener(new PropertyAccessor());
   $listener->addMapping('Thengine\Domain\User\Model\UserProfile', 'address');

2. Now the listener needs to be registered with the Doctrine EventManager.

   <?php
   
   use Doctrine\Common\EventManager;
   use Doctrine\ORM\Events;
   use Symfony\Component\PropertyAccess\PropertyAccessor;
   use Tarifhaus\Doctrine\ORM\NullableEmbeddableListener;
   
   $listener = new NullableEmbeddableListener(new PropertyAccessor());
   
   $evm = new EventManager();
   $evm->addEventListener([Events::postLoad], $listener);

Tip: It's highly recommended to use Doctrine entity listener when configuring the listener, so it is only executed for the entities it actually applies to.

Symfony

In case you are using Symfony with Doctrine, you can register the listener as a service and configure it this way.

services:
    tarifhaus.doctrine.nullable_embeddable_listener:
        public: false
        class: Tarifhaus\Doctrine\ORM\NullableEmbeddableListener
        arguments:
            - '@property_accessor'
        calls:
            - ['addMapping', ['Thengine\Domain\User\Model\UserProfile', 'address']]
        tags:
            - { name: 'doctrine.orm.entity_listener', entity: '\Thengine\Domain\User\Model\UserProfile', event: 'postLoad' }

Usage

The embeddable class needs to implement the Tarifhaus\Doctrine\ORM\NullableEmbeddableInterface. It contains a method isNull(): bool which tells the listener, whether the loaded embeddable should be treated as and therefore replaced with null.