Multitenancy: @TenantId support in schema mode

[Nahuel92]

Hi there!

I would like to know if it's possible to use Micronaut Data JDBC in conjunction with:

• Schema-mode multitenancy
• The @TenantId annotation

This is because my particular workflow doesn't trigger from an HTTP request (or anything supported by any of the built-in tenant resolvers bundled with Micronaut). Instead, tenants come from data fetched by my app from external systems at runtime.

My current code looks like this:

Application.yml

micronaut:
  data:
    multi-tenancy:
      mode: SCHEMA

# One datasource, which contains multiple schemas with identical tables I want to map to one entity
datasources:
  default:
    url: jdbc:postgresql://localhost:5444/postgres
    dialect: postgres
    driver-class-name: org.postgresql.Driver
    username: changeme
    password: changeme

Repository

@JdbcRepository(dialect = Dialect.POSTGRES)
public interface MyEntityRepository extends CrudRepository<MyEntity, Integer> {
}

Entity

@MappedEntity(value = "my_entity")
public record Site(
        @TenantId String tenant,
        @MappedProperty("id") @Id @GeneratedValue @Nullable Integer id,
        @MappedProperty("column_a") String columnA) {
}

Client code

@Singleton
class MyService {
    private final MyRepository myRepository;

    MyService(final MyRepository myRepository) {
        this.myRepository = myRepository;
    }

    @io.micronaut.scheduling.annotation.Scheduled(fixedRate = "5m")
    public void doStuff() {
        // Tenants are dynamically fetched from external systems (HTTP calls or DB calls), I'm manually setting the values here to keep the example simple

        // Saving to schema A
        final var myEntity = new MyEntity("schema_a", null, "any value");
        myRepository.save(myEntity);

        // Updating to schema A (assuming "1" is the id of the previous entity)
        final var updatedEntity = new MyEntity("schema_a", 1, "updated value");
        myRepository.update(myEntity);

        // Saving to schema B
        final var myEntity2 = new MyEntity("schema_b", null, "any value");
        myRepository.save(myEntity2);

        // Updating to schema B (assuming "1" is the id of the previous entity)
        final var updatedEntity2 = new MyEntity("schema_b", 1, "updated value");
        myRepository.update(myEntity2);
    }
}

But that leads to the exception ERROR: column \"column_a\" of relation \"my_entity\" does not exist because the tenant seems to not be resolved.

My question is if this scenario is supported by Micronaut Data JDBC and, if not, if I should rely to some other mechanism instead.

Thanks in advance!