How to fix "Cannot autowire service: Argument references class but no such service exists" in Sylius?

Question

In Sylius 1.11, after creating a new Campaign entity using the maker bundle, I get this error when trying to fetch a campaign using its repository:

Cannot autowire service "App\Repository\CampaignRepository": argument "$class" of method "Doctrine\ORM\EntityRepository::__construct()" references class "Doctrine\ORM\Mapping\ClassMetadata" but no such service exists.

This seems to be the code that trigger the error:

<?php

namespace App\Controller;

use App\Repository\CampaignRepository;

class CampaignController extends AbstractController {
    protected CampaignRepository $repository;

    public function __construct(CampaignRepository $repository) {
        $this->repository = $repository;
    }

    public function details(string $id)
    {
        $campaign = $this->repository->find($id);

        dd($campaign);
    }
}

The App\Repository\CampaignRepository exists and is defined as follow, which is what the Sylius documentation recommends:

<?php

namespace App\Repository;

use App\Entity\Campaign;
use Doctrine\Bundle\DoctrineBundle\Repository\ServiceEntityRepository;
use Sylius\Bundle\ResourceBundle\Doctrine\ORM\EntityRepository;

/**
 * @extends ServiceEntityRepository<Campaign>
 *
 * @method Campaign|null find($id, $lockMode = null, $lockVersion = null)
 * @method Campaign|null findOneBy(array $criteria, array $orderBy = null)
 * @method Campaign[]    findAll()
 * @method Campaign[]    findBy(array $criteria, array $orderBy = null, $limit = null, $offset = null)
 */
class CampaignRepository extends EntityRepository
{
}

How to fix this error?

Answer 1

TL;DR

It turns out Sylius is quite picky on both the type hinting and the variable name. This is due to how Symfony's dependency injection works and how Sylius chose to use it.

Change the constructor to:

public function __construct(
   \Sylius\Component\Resource\Repository\RepositoryInterface $campaignRepository
) {
    $this->repository = $campaignRepository;
}

How are you supposed to guess that?

You need to use the bin/console debug:container command. But if you try, you'll run into the same error message as when running you controller action.

What you need to do is:

1. comment any method that use the symfony's dependency injection feature to access an instance of your repository (in our case the App\Controller\CampaignController::__construct() method)
2. run the bin/console debug:container CampaignRepository
   This will return you a list of services:

bin/console debug:container CampaignRepository

Select one of the following services to display its information:
[0] App\Repository\CampaignRepository
[1] Doctrine\Persistence\ObjectRepository $campaignRepository
[2] Doctrine\Common\Collections\Selectable $campaignRepository
[3] Sylius\Component\Resource\Repository\RepositoryInterface $campaignRepository
[4] Sylius\Bundle\ResourceBundle\Doctrine\ORM\EntityRepository $campaignRepository
[5] Doctrine\ORM\EntityRepository $campaignRepository

3. chose a combination of class name & parameter to use as your constructor parameter (I went with Sylius\Component\Resource\Repository\RepositoryInterface $campaignRepository but any of the suggestions with a parameter name should work)
4. uncomment the method you commented on step 1 & update its signature
5. voilà

If you're curious how this works, have a look here: https://symfony.com/doc/current/service_container/autowiring.html#dealing-with-multiple-implementations-of-the-same-type