Symfony 3: Inject entity repository into service controller

In this post I’m going to explain how to inject a specific entity repository into a controller defined as a service. We assume that you already created a Doctrine entity and a repository (we are calling it MyEntity here).

The Controller

We define a simple controller that offers a JSON REST-API endpoint with all the entities we saved in our database. Because we wish to use the dependency injection, we have to define the controller as a service.

    <?php # src/AppBunlde/Controller/MyServiceName.php

    namespace AppBundle\Controller;

    use Sensio\Bundle\FrameworkExtraBundle\Configuration\Route;
    use Symfony\Component\HttpFoundation\JsonResponse;

    /**
     * Very important is the Route annotation with service parameter!
     * @Route("/api/myentity", service="my_service_name")
     */
    class MyServiceName {

        private $repository;

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

        /**
         * @Route("/")
         */
        public function someAction() {
            $entities = $this->repository->findAll();

            $response = new JsonResponse();
            $response->setContent(json_encode($entities));
            return $response;
        }
    }

    ?>

Watch out for the Route annotation on the class! Otherwise you’ll later get an exception like this:

Catchable Fatal Error: Argument 1 passed to AppBundle\Controller\MyServiceName::__construct() must be an instance of AppBundle\Repository\MyEntityRepository, none given, called in /.../var/cache/dev/classes.php on line 2081 and defined

This happens because Symfony does not instantiate the controller as a service via dependency injection, but rather as it would a normal class by plainly calling the constructor.

Register the service

Now we register the service and configure what to inject.

    # app/config/services.yml

    services:
        my_service_name:
            class: AppBundle\Controller\MyServiceName
            arguments: ["@=service('doctrine.orm.entity_manager').getRepository('AppBundle:MyEntity')"]

So we just declare our controller as a service and use Symfony´s expression syntax to boil down the dependency to our MyEntityRepository.

The Controller

Register the service

Further reading