null is not allowed in Flask restx's expect

[samue1c]

Note: I am using restx's Namespace for the following:

For request payload validation, I have something like this:

@ns.route('/event')
class EventResource(Resource):
    @ns.expect(event_model, validate=True)
    def post(self):
        validated_data = ns.payload  # Use the payload directly from the request
        logger.info(f"Validated event data: {validated_data}")
        ...

For the model, I have a nested model like this:

event_department_model = ns.model('EventDepartment', {
    'identifier': fields.String(required=True, description='Department identifier'),
    'name': fields.String(required=True, description='Department name')
})

event_model = ns.model('Event', {
    ...
    'department': fields.Nested(event_department_model, required=False, allow_null=True, skip_none=True, nullable=True, description='Department information'),
    ...
}

I want department in the input JSON payload to accept a department object(dictionary) or null. In event_model, I have already tried required=False, allow_null=True, nullable=True, skip_none=True and different combinations of these options, but nothing seems to be letting department accepting null.

However, no matter what combinations I have tried, I am getting the same error:

{
    "errors": {
        "department": "None is not of type 'object'"
    },
    "message": "Input payload validation failed"
}

Expected Behavior

It should accept the department property as being null

Actual Behavior

Getting error message of "None is not of type 'object'"

Error Messages/Stack Trace

{
    "errors": {
        "department": "None is not of type 'object'"
    },
    "message": "Input payload validation failed"
}

Environment

• Python version 3.12.2
• Flask version 3.1
• Flask-RESTX version 1.3
• Other installed Flask extensions
  • Flask-SQLAlchemy
  • Flask-Mail
  • Flask-Limiter
  • Flask-Session
  • python-dotenv
  • mysql-connector-python

Additional Context

I have already tried required=False, allow_null=True, nullable=True, skip_none=True and different combinations of these options but it did not work for me.

[peter-doggart]

The current schema setup doesn't allow fields.Nested to be null from what I can see. It looks like some people were able to quickly work around this on flask-restplus (the old rextx project) by creating a subclass of Nested with a schema that allows null. Might be worth a try?

noirbizarre/flask-restplus#285 (comment)