DoesNotExist: Getting "Group matching query does not exist." error while saving a UserCreationForm of Django

Question

I'm trying to save UserCreationForm of Django's built in auth application's form, using following in forms.py

from django.contrib.auth.forms import UserCreationForm
from django.contrib.auth.models import User
from django import forms
from .models import *
class CreateUserForm(UserCreationForm):
    class Meta:
        model = User
        fields = ['username', 'email', 'password1', 'password2']

My unauthenticated decorator is:

def unauthenticated_user(view_func):
    def wrapper_func(request, *args, **kwargs):
        if request.user.is_authenticated:
            return redirect('home')
        else:
            return view_func(request, *args, **kwargs)
    return wrapper_func

And views function looks like:

@unauthenticated_user
def registerPage(request):
    form = CreateUserForm() 
    if request.method == 'POST':
        form = CreateUserForm(request.POST)
        if form.is_valid():
            user = form.save()
            username = form.cleaned_data.get('username')
            messages.success(request, 'Account was created for ' + username)
            return redirect('login')
    context = {'form':form}
    return render(request, 'accounts/register.html', context)

Complete Traceback is:

Traceback (most recent call last):
  File "/Users/jatinsinghbhati/Documents/workspaces/djangoenv/lib/python3.9/site-packages/django/core/handlers/exception.py", line 47, in inner
    response = get_response(request)
  File "/Users/jatinsinghbhati/Documents/workspaces/djangoenv/lib/python3.9/site-packages/django/core/handlers/base.py", line 181, in _get_response
    response = wrapped_callback(request, *callback_args, **callback_kwargs)
  File "/Users/jatinsinghbhati/Documents/workspaces/pollsite/accounts/decorators.py", line 9, in wrapper_func
    return view_func(request, *args, **kwargs)
  File "/Users/jatinsinghbhati/Documents/workspaces/pollsite/accounts/views.py", line 26, in registerPage
    user = form.save()
  File "/Users/jatinsinghbhati/Documents/workspaces/djangoenv/lib/python3.9/site-packages/django/contrib/auth/forms.py", line 138, in save
    user.save()
  File "/Users/jatinsinghbhati/Documents/workspaces/djangoenv/lib/python3.9/site-packages/django/contrib/auth/base_user.py", line 67, in save
    super().save(*args, **kwargs)
  File "/Users/jatinsinghbhati/Documents/workspaces/djangoenv/lib/python3.9/site-packages/django/db/models/base.py", line 753, in save
    self.save_base(using=using, force_insert=force_insert,
  File "/Users/jatinsinghbhati/Documents/workspaces/djangoenv/lib/python3.9/site-packages/django/db/models/base.py", line 801, in save_base
    post_save.send(
  File "/Users/jatinsinghbhati/Documents/workspaces/djangoenv/lib/python3.9/site-packages/django/dispatch/dispatcher.py", line 177, in send
    return [
  File "/Users/jatinsinghbhati/Documents/workspaces/djangoenv/lib/python3.9/site-packages/django/dispatch/dispatcher.py", line 178, in <listcomp>
    (receiver, receiver(signal=self, sender=sender, **named))
  File "/Users/jatinsinghbhati/Documents/workspaces/pollsite/accounts/signals.py", line 10, in customer_profile
    group = Group.objects.get(name='customer')
  File "/Users/jatinsinghbhati/Documents/workspaces/djangoenv/lib/python3.9/site-packages/django/db/models/manager.py", line 85, in manager_method
    return getattr(self.get_queryset(), name)(*args, **kwargs)
  File "/Users/jatinsinghbhati/Documents/workspaces/djangoenv/lib/python3.9/site-packages/django/db/models/query.py", line 429, in get
    raise self.model.DoesNotExist(

Exception Type: DoesNotExist at /accounts/register/
Exception Value: Group matching query does not exist.

My model is:

class Customer(models.Model):
    user = models.OneToOneField(User, null=True, blank=True, on_delete=models.CASCADE)
    name = models.CharField(max_length=200, null=True)
    phone = models.CharField(max_length=200, null=True)
    email = models.CharField(max_length=200, null=True)
    profile_pic = models.ImageField(default="profile1.png", null=True, blank=True)
    date_created = models.DateTimeField(auto_now_add=True, null=True)

    def __str__(self):
        return self.name

My signals.py file:

from django.db.models.signals import post_save
from django.contrib.auth.models import User
from django.contrib.auth.models import Group
from .models import Customer
def customer_profile(sender, instance, created, **kwargs):
    if created:
        group = Group.objects.get(name='customer')
        instance.groups.add(group)
        Customer.objects.create(
            user=instance,
            name=instance.username,
            )
        print('Profile created!')
post_save.connect(customer_profile, sender=User)

Please help me with this. Kindly note that it is saving the values to the SQL DB successfully but returning this error and not moving anywhere ahead user = form.save() line.

Any help is much appreciated. Thanks!

Answer 1

It appears that there is no Group with name='customer'. You should use ensure that a group like that exists. One method would be to use the get_or_create method to get the object if it exists or create and get it:

def customer_profile(sender, instance, created, **kwargs):
    if created:
        group, created = Group.objects.get_or_create(name='customer')
        instance.groups.add(group)
        Customer.objects.create(
            user=instance,
            name=instance.username,
            )
        print('Profile created!')