Use of Django Internal Property

[kahnvex]

Python Social Auth's Django App directly references a property that is marked for internal use only.

field = UserSocialAuth.user_model()._meta.get_field(username_field)

The use of _meta here is problematic for applications that are service oriented by nature. If your user store is a service consumed by a client that houses python social auth (like a legacy user store) you should not have to implement all the "internal" stuff (like _meta) that a Django model has. By adding a simple check this could probably be avoided.

[kahnvex]

Suggest:

@classmethod
def username_max_length(cls):
    username_field = cls.username_field()
    user_model = UserSocialAuth.user_model()
    field = getattr(user_model, username_field)
    if hasattr(field, 'max_length'):
        return field.max_length

    return settings.USERNAME_FIELD_MAX_LENGTH

[omab]

Could you show me an example where _meta doesn't work? _meta is populated by Django ORM when the model class is defined, you can't do getattr(User, 'username'), that will drop an attribute error since the model class doesn't have that attribute.

[omab]

Closing, reopen if needed.