Django | Extend User Model | Using a One-To-One Link | Profile

extend_user_model_using_OneToOneField.py

from django.db import models
from django.contrib.auth.models import User

class Profile(models.Model):
    user = models.OneToOneField(User, on_delete=models.CASCADE)
    bio = models.TextField(max_length=500, blank=True)
    location = models.CharField(max_length=30, blank=True)
    birth_date = models.DateField(null=True, blank=True)

    
"""
Hooking the create_user_profile and save_user_profile methods to the User model, whenever a save event occurs. 
This kind of signal is called post_save.
"""
@receiver(post_save, sender=User)
def create_user_profile(sender, instance, created, **kwargs):
    if created:
        Profile.objects.create(user=instance)

@receiver(post_save, sender=User)
def save_user_profile(sender, instance, **kwargs):
    instance.profile.save()    

@receiver(post_save, sender=User)
def save_user_profile(sender, instance, **kwargs):
    instance.profile.save()  

What does profile refers to ?
I guess the correct line would be
instance.Profile.save()

@receiver(post_save, sender=User)
def save_user_profile(sender, instance, **kwargs):
    instance.profile.save()  

What does profile refers to ?
I guess the correct line would be
instance.Profile.save()

I also was confused by this. But I don't think your suggestion is correct either.

instance would be an object of User type, so he is assuming that it has an attribute profile, which it doesn't.

@joshua-koehler , @Bhupesh-V apologies for the delayed response.

The statement instance.Profile.save() (where instance is an object of User) is valid. The only issue in the code is implicit declaration of the related_name param in user field user = models.OneToOneField(User, on_delete=models.CASCADE).

So, the explicit declaration of the related_name param in user field should be: user = models.OneToOneField(User, on_delete=models.CASCADE, related_name='profile').

Note: the addition of param related_name='profile'.

If you do not specify the related_name argument for the OneToOneField, Django will use the lowercase name of the current model as default value.

Ref: https://docs.djangoproject.com/en/4.0/ref/models/fields/#onetoonefield