Adding One-To-One field to the default Django user model - django

Question

I'm trying to add one-to-one field to the default Django user model but
for some reason I keep getting error from the database:
django.db.utils.IntegrityError: NOT NULL constraint failed: frontend_usermodel.test_suites_id
this is models file:
from django.contrib.auth.models import User
from django.db.models.signals import post_save
from django.dispatch import receiver
from django.db import models
class TestSuite(models.Model):
id = models.IntegerField(primary_key=True)
...
...
def __str__(self):
return self.name
class Meta:
ordering = ('name',)
class UserModel(models.Model):
user = models.OneToOneField(User, on_delete=models.CASCADE)
test_suites = models.OneToOneField(TestSuite, on_delete=models.CASCADE)
def __str__(self):
return self.email
#receiver(post_save, sender=User)
def create_user_profile(sender, instance, created, **kwargs):
if created:
UserModel.objects.create(user=instance)
#receiver(post_save, sender=User)
def save_user_profile(sender, instance, **kwargs):
instance.profile.save()
What can I do to solve this ?
UPDATE:
class TestSuite(models.Model):
id = models.IntegerField(primary_key=True)
user = models.ForeignKey(User, on_delete=models.CASCADE)
...
...

Answer 1

Your UserModel requires both fields user and test_suites, so this line:
UserModel.objects.create(user=instance)
will fail because test_suites is None and therefore the NULL constraint is violated. You have to pass also a TestSuite instance to create your UserModel instance.
Although I don't know the exact business requirements of your application, it would seem more logical to me to set the OneToOneField on the TestSuite. I can imagine a user without test suite, and I would expect only when you create a test suite, you would assign the user. By doing that, you won't need a TestSuite instance when creating a User.