paginate decorator causes validation to fail

[johnbridstrup]

I have used the @paginate decorator successfully multiple times now, but for some reason it is causing validation to fail on a new endpoint (that works without pagination). I have a feeling this is because of the schema, which has a nested schema and a resolved value, because that is the only real difference between it and the working ones. Am I missing something from the documentation or is there a known reason this is happening?

Schema

class MyModelResponseSchema(ModelSchema):
    related_model: RelatedModelResponseSchema
    calculated_property: int
    creator: UserLimitedSchema

    @staticmethod
    def resolve_calculated_property(obj):
        return obj.calculated_property

    class Meta:
        model = MyModel
        fields = [
            "related_model",
            "max_amount",
            "max_increment",
            "creator",
        ]

Endpoint

@router.get(
    "myEndpoint",
    auth=JWTAuth(),
    response={200: List[MyModelResponseSchema], codes_4xx: DefaultError},
    url_name="service_my_endpoint",
)
@paginate  # <--- Works fine without this decorator
def my_view(request):
    return 200, MyModel.objects.all()

Output

pydantic_core._pydantic_core.ValidationError: 8 validation errors for NinjaResponseSchema
response.items.0.related_model
  Field required [type=missing, input_value=<ninja.schema.DjangoGette...bject at 0x7f8bbb8852c0>, input_type=DjangoGetter]
response.items.0.calculated_property
  Field required [type=missing, input_value=<ninja.schema.DjangoGette...bject at 0x7f8bbb8852c0>, input_type=DjangoGetter]
response.items.0.creator
  Field required [type=missing, input_value=<ninja.schema.DjangoGette...bject at 0x7f8bbb8852c0>, input_type=DjangoGetter]
response.items.0.max_amount
  Field required [type=missing, input_value=<ninja.schema.DjangoGette...bject at 0x7f8bbb8852c0>, input_type=DjangoGetter]
...

Any help would be nice, thanks!

[johnbridstrup]

Okay, I've removed the nested schemas and resolver and its still happening. I am now very confused why its specifically happening for this model/endpoint and not the others, which appear to be exactly the same (return .all() for a simple query)

[johnbridstrup]

I figured out why this is happening. It seems you cannot include an explicit response code when returning from the method. I think this should be probably allowed. I'll look into making a PR at some point

[johnbridstrup]

from the apply pagination method

{'items': <QuerySet [<Model1: 1>, <Model1: 2>]>, 'count': 2}
{'items': (200, <QuerySet [<Model2: 1>]>), 'count': 2}  # <--- It is trying to paginate the tuple

[Vernadskii]

Indeed, I have no idea how to return 4xx error in function with @paginate decorator. It doesn't make sense if you can't raise it. Suppose I have a query parameter, that didn't pass validation and I have to return message with that detail. How can I do it?

[Vernadskii]

Ok, found solution here #940 (comment)
It would be better to mention this case on page https://django-ninja.dev/guides/response/pagination/