Does eox-core support custom registration models? #347

Description

I'm trying to use eox-core to register users on an instance with a custom registration model that adds a birthdate field. Registration did not work with the custom model enabled, but it worked when I temporarily disabled it.

My impression is that the custom fields may not be picked up when processing the registration request, but I'm not sure whether this is a bug, an unsupported use case, or something missing in our configuration or request. I'm opening this issue to get some help confirming the expected behavior.

To Reproduce

These are the steps I tried:

1. Configure a custom registration model that adds a birthdate field.
2. With public registration disabled, send a user registration request through eox-core.
3. Temporarily disable the custom registration model and retry registration through eox-core.

In my tests, registration failed with the custom model enabled and succeeded after disabling it.

Expected behavior

I would expect eox-core to handle the additional fields defined by the custom registration model, but I'd like to confirm whether this is supported and whether it requires any additional configuration or a specific request format.

Screenshots

With this payload:

curl -X 'POST' \
  'https://lms.example.com/eox-core/api/v1/user/' \
  -H 'accept: application/json' \
  -H 'Content-Type: application/json' \
  -H 'X-CSRFTOKEN: XXX' \
  -d '{
  "email": "maria.XXXX",
  "username": "majo-edu",
  "password": "XXX",
  "fullname": "Maria Grimaldi",
  "activate_user": true,
  "skip_password": false,
  "terms_of_service": true,
  "birthdate": "16/06/1997"
}'

We get:

Additional context

Public registration is disabled on the client's instance. We are evaluating eox-core as an alternative to creating users through Django admin, which the client has already tried but would prefer not to keep using. I recall the custom model working correctly through the standard registration page, but I have not been able to verify this again because public registration is disabled.

Has anyone used eox-core with a similar setup?