Summary

In typical hexagonal architecture you are very likely to want to use the DTOs in the application layer while the litestar would only live in the infrastructure layer.

Basic Example

from litestar.dto import DTOData

class ProductService:
    def create_product(self, product_dto: DTOData[ProductModel]) -> ProductModel:
        product_model= product_dto.create_instance(
            id=ProductId(uuid4()),
            creation_ts=self.time_service.now(),
        )

        return self.product_repo.store_product(product_model)

Drawbacks and Impact

• The litestar.dto in import section pretty much ties us to use the litestar as a whole. We have to pretty much install whole litestar so using other APIs with litestar.dto is not plausible because whole litestar has to be installed anyway.
• It's inplausible to use litestar.dto in context where we don't use the API at all (like the CLI interface or message queues)

Unresolved questions

• The module name would probably have to be changed from dto to something less generic.
• The dto module would probably still have to be included as a part of the litestar project.