Read replica database connection never used, goes back to default

Question

I'm following the documentation here https://symfony.com/doc/current/reference/configuration/doctrine.html about setting up alternative database connections for the purpose of read replication. For reference I'm using AWS Aurora PostgreSQL with end points for primary and read only.

I've set the this for my doctrine.yaml

doctrine:
    dbal:
        default_connection: default
        connections:
            default:
                url: '%env(resolve:DATABASE_URL)%'
            read:
                url: '%env(resolve:READ_URL)%'
    orm:
        default_entity_manager: default
        entity_managers:
            default:
                connection: default
                naming_strategy: doctrine.orm.naming_strategy.underscore_number_aware
                auto_mapping: true
                dql:
                    datetime_functions:
                        date_trunc: App\DoctrineExtensions\DateTrunc
                mappings:
                    App:
                        is_bundle: false
                        type: annotation
                        dir: '%kernel.project_dir%/src/Entity'
                        prefix: 'App\Entity'
                        alias: App
            read:
                connection: read
                naming_strategy: doctrine.orm.naming_strategy.underscore_number_aware
                auto_mapping: false
                dql:
                    datetime_functions:
                        date_trunc: App\DoctrineExtensions\DateTrunc
                mappings:
                    App:
                        is_bundle: false
                        type: annotation
                        dir: '%kernel.project_dir%/src/Entity'
                        prefix: 'App\Entity'
                        alias: App
        auto_generate_proxy_classes: true

And calling the read only orm as:

$user = $this->getDoctrine()->getRepository(User::class, 'read')->findOneBy(['email' => $payload['email']]);

as an example.

If I call this it still goes to the default database. If I misname it Symfony throws an exception as expected so I can confirm the config is being picked up and loading correctly.

How is my config or call incorrect that it's still requesting from the default database connection or is there any better way to define read replicas for the data connection? I haven't found any current documentation for it.

Answer 1

According to this:

One entity can be managed by more than one entity manager. This however results in unexpected behavior when extending from ServiceEntityRepository in your custom repository. The ServiceEntityRepository always uses the configured entity manager for that entity. In order to fix this situation, extend EntityRepository instead and no longer rely on autowiring:

So you should make sure your repository extends EntityRepository instead of ServiceEntityRepository.

Then you should now always fetch this repository using ManagerRegistry::getRepository().

So basically this would work since $this->getDoctrine() return an instance of ManagerRegistry.

$user = $this->getDoctrine()->getRepository(User::class, 'read')->findOneBy(['email' => $payload['email']]);

The downside is you will not be able to use autowiring for the repository itself.

So this would not work unless you pass that repository manually.

public function __construct(UserRepository $userRepository)
{
    $this->userRepository = $userRepository;
}