Excluding None (optional fields) from json response bodies

[bunny-therapist]

Many of our pydantic models have optional fields (field: Optional[T] = None). Those fields are not listed as required in the equivalent json schema. When I use those models as response bodies with litestar, those fields get included with a null value in the serialized response. How can I exclude those fields completely from the body?

When doing this with pydantic natively, I can just pass exclude_none=True to model_dump. When building an app with FastAPI I can set responce_model_exclude_none=True for the endpoint. With litestar, I cannot figure out any way to do this other than to just convert the model to a dict myself and return that. However, that seems to go against the intention of the framework...

Is there any way to exclude optional fields from the serialized json response?

[bunny-therapist]

On a related note, I have a similar concern regarding excluding default values (exclude_defaults=True).

I simply cannot see how to customize the serialization of the pydantic models (other than develop some kind of plugin I suppose, but that seems very complicated).

[bunny-therapist]

Is type_encoders the recommended solution?

[provinzkraut]

That's the best way to do this for Pydantic, yes.