Symfony 3 - PATCH Method doesn't remove/replace elements in a collection - php

Question

In my entity file Collection.php I have self referencing many to many relationship:
/**
* #ORM\ManyToMany(targetEntity="AppBundle\Collection")
* #ORM\JoinTable(name="collection_related_collections",
* joinColumns={#ORM\JoinColumn(name="collection_source", referencedColumnName="id")},
* inverseJoinColumns={#ORM\JoinColumn(name="collection_target", referencedColumnName="id")}
* )
* #JMS\Groups({"collection_related_collections"})
* #JMS\Expose()
* #Assert\Count(
* max = 3,
* maxMessage = "You cannot specify more than {{ limit }} related collections"
* )
* #var Collection[]|ArrayCollection $relatedCollections
*/
protected $relatedCollections;
This is processed in a controller by a form handler:
$this->get('app_bundle.form.handler.api_form_handler')
->process($form);
Finnally my CollectionFormType.php has RelatedCollection field:
->add('relatedCollections', EntityType::class, [
'required' => false,
'choice_value' => 'hashId',
'choice_label' => function (Collection $collection) {
return $collection->getName();
},
'multiple' => true,
'expanded' => true,
'class' => Collection::class,
'query_builder' => function (CollectionRepository $collectionRepository) {
return $collectionRepository->getQueryBuilder();
}
])
Everything works fine when I am trying to PATCH an empty relatedCollection field:
[PATCH] http://symfony.dev/api/collections/{collectionHashId}
{
"collection": {
"relatedCollections": ["7D68076025", "196208D03D"]
}
}
But I cannot remove/replace elements trying
[PATCH] http://symfony.dev/api/collections/{collectionHashId}
{
"collection": {
"relatedCollections": ["7D68076025"]
}
}
This action has no effect. As a result value of relatedCollection field remains the same as I set it in the previous request:
"relatedCollections": ["7D68076025", "196208D03D"]
Also, I cannot remove relatedCollections values by sending an empty array [], because it makes no changes at all.
Is there a way to replace/remove ArrayCollection values using PATCH Method?

Answer 1

Have you tried this with PUT as well with a similar result? I suspect this is caused by the "owner" of the relationship being the child; in this case RelatedCollection as I understand it.
You'll need to update the owning side of the relationship if that is the case. Check this out for more information: http://docs.doctrine-project.org/projects/doctrine-orm/en/latest/reference/unitofwork-associations.html