history.txt

mkdir django_signals
cd django_signals
python -m venv ENV
source ENV/bin/activate
(source /home/j3/django_signals/ENV/bin/activate)
pip install django
python manage.py createproject signals
cd signal
python manage.py createapp base
cd base/model.py
Type these lines & hit save:
----------------------------------------
from django.db import models                   
from django.contrib.auth.models import User    
from django.db.models.signals import post_save 


class Profile(models.Model):    
               
     user = models.OneToOneField(User, on_delete=models.CASCADE, blank=True, null=True) 
     first_name = models.CharField(max_length=200, blank=True, null=True) 
     last_name = models.CharField(max_length=200, blank=True, null=True) 
     phone = models.CharField(max_length=200, blank=True, null=True) 
     
     def __str__(self):                                            
         return str(self.user) 
'''

    def create_profile(sender, instance, created, **kwargs):
        if created:
            Profile.objects.create(user=instance)
            print('****************')
            print('Profile created!')
            print('****************')

    post_save.connect(create_profile, sender=User)

    def update_profile(sender, instance, created, **kwargs):
        if created is False:
            instance.profile.save()
            print('****************')
            print('Profile Updated!')
            print('****************')

    post_save.connect(update_profile, sender=User)
    
'''
----------------------------------------
This model connect Django User + my Profile ;)  
Now Go to admin.py:
----------------------------------------
from django.contrib import admin
from base.models import Profile

admin.site.register(Profile)
----------------------------------------
Go to apps.py
----------------------------------------
from django.apps import AppConfig


class BaseConfig(AppConfig):
    # default_auto_field = 'django.db.models.BigAutoField'
    name = 'base'

    def ready(self):
        import base.signals

----------------------------------------
Create & Go to signals.py:
----------------------------------------
from django.contrib.auth.models import User
from base.models import Profile
from django.db.models.signals import post_save
from django.dispatch import receiver


@receiver(post_save, sender=User)
def create_profile(sender, instance, created, **kwargs):
    if created:
        Profile.objects.create(user=instance)
        print('****************')
        print('Profile created!')
        print('****************')


# post_save.connect(create_profile, sender=User)

@receiver(post_save, sender=User)
def update_profile(sender, instance, created, **kwargs):
    if created is False:
        instance.profile.save()
        print('****************')
        print('Profile Updated!')
        print('****************')

----------------------------------------
python manage.py makemigrations
python manage.py migrate
pip freeze > requirement.txt
code .
exit
Inside vscode:
Go to /admin
Create & Login as superuser
create/ update a user
SEE Profile...

Output:
--------------------------
[05/Apr/2023 02:25:04] "GET /admin/auth/user/add/ HTTP/1.1" 200 7383
[05/Apr/2023 02:25:04] "GET /admin/jsi18n/ HTTP/1.1" 200 3195
****************
Profile created!
****************
[05/Apr/2023 02:25:35] "POST /admin/auth/user/add/ HTTP/1.1" 302 0
[05/Apr/2023 02:25:35] "GET /admin/auth/user/23/change/ HTTP/1.1" 200 16008
[05/Apr/2023 02:25:35] "GET /admin/jsi18n/ HTTP/1.1" 200 3195
****************
Profile Updated!
****************
[05/Apr/2023 02:26:01] "POST /admin/auth/user/23/change/ HTTP/1.1" 302 0
[05/Apr/2023 02:26:01] "GET /admin/auth/user/ HTTP/1.1" 200 8968
[05/Apr/2023 02:26:01] "GET /admin/jsi18n/ HTTP/1.1" 200 3195
--------------------------
There you have!
Hope this will be helpful!
j3
March, 2023