Extension

App\Util\Doctrine\OwnerExtension.php

<?php 

class OwnerExtension implements QueryCollectionExtensionInterface
{

    private $tokenStorage;

    public function __construct(TokenStorageInterface $tokenStorage)
    {
        $this->tokenStorage = $tokenStorage;
    }

    public function applyToCollection(
        QueryBuilder $queryBuilder,
        QueryNameGeneratorInterface $queryNameGenerator,
        string $resourceClass,
        string $operationName = null
    ) {
        $token = $this->tokenStorage->getToken();
        if ($token === null) {
            return;
        }
        $user = $token->getUser();
        if (!$user instanceof User) {
            return;
        }
        
        $rootAlias = $queryBuilder->getRootAliases()[0];
        switch ($resourceClass) {
            case Subject::class:
                $queryBuilder->andWhere(sprintf('%s.user = :current_user', $rootAlias));
                break;
            default:
                return;
        }

        $queryBuilder->setParameter('current_user', $user->getId());
    }