get_or_create throws Integrity Error

Question

Given that the whole point of object.get_or_create() is to get the object if it already exists, I fail to see why it's throwing an integrity error for this code:

class UserAdd(TemplateView):

def post(self, request, *args, **kwargs):
    context = self.get_context_data(*args, **kwargs)
    form = UserAddForm(request.POST)
    if form.is_valid():
        first_name = form.cleaned_data['first_name']
        last_name = form.cleaned_data['last_name']
        myemail = form.cleaned_data['email']
        mypass = form.cleaned_data['password']
        if myemail and mypass:
            myuser,created = User.objects.get_or_create(email=myemail, username=myemail, first_name=first_name, last_name=last_name)
            if created:
                myuser.set_password(mypass)
    return HttpResponseRedirect('/')

Here is the error:

django.db.utils.IntegrityError IntegrityError: (1062, "Duplicate entry '[email protected]' for key 'username_UNIQUE'")

Anyone know what's going on?

Answer 1

The parameters sent into the get_or_create method need to match exactly, or django's ORM would try to create a new object, and since a primary key/unique column constraint would be violated, you are getting the error.

Try this:

if form.is_valid():
    first_name = form.cleaned_data['first_name']
    last_name = form.cleaned_data['last_name']
    myemail = form.cleaned_data['email']
    mypass = form.cleaned_data['password']
    if myemail and mypass:
        myuser,created = User.objects.get_or_create(email=myemail, defaults = {'username': myemail, 'first_name': first_name, 'last_name': last_name})
        if created:
            myuser.set_password(mypass)

return HttpResponseRedirect('/')

Read more on get_or_create here. The defaults= argument is what you needed.