How to configure dependency injection for repository class in symfony 3

Question

Symfony generator generated the following class of repository:

namespace AppBundle\\Repository;
use AppBundle\\Entity\\GroupEntity;

/**
 * GroupEntityReposi         


        

Answer 1

Since Symfony 3.4 you can avoid factory and use a TagRepository service that extends ServiceEntityRepository class instead of directly EntityRepository.

use AppBundle\Entity\GroupEntity;
use Doctrine\Bundle\DoctrineBundle\Repository\ServiceEntityRepository;
use Symfony\Bridge\Doctrine\RegistryInterface;

class GroupEntityRepository extends ServiceEntityRepository
{
    public function __construct(RegistryInterface $registry)
    {
        parent::__construct($registry, GroupEntity::class);
    }
}

With this method, your service would be automatically registered with autowiring feature.

You can also do better in all Symfony version by using composition over inheritance.

final class GroupEntityRepository
{
    /** @var EntityManagerInterface */
    private $entityManager;

    /** @var ObjectRepository */
    private $objectRepository;

    public function __construct(EntityManagerInterface $entityManager)
    {
        $this->entityManager = $entityManager;
        $this->objectRepository = $this->entityManager->getRepository(GroupEntity::class);
    }

This service can also be autowiring. You can go further by respecting the SOLID principle and create an interface. There is a good explanation in this article (Repository Pattern in Symfony)