Django: form validation errors on form creation

Django: form validation errors on form creation

Let's say I have a Django form with ChoiceField:

Let's say I have a Django form with ChoiceField:

class MyForm(forms.Form):
    name = forms.CharField(label="Name", required=True)
    some_object = forms.ChoiceField(label="Object", choices=[(0, '-----')] + [(x.id, x.name) for x in Obj.objects.all()])

Choisefield is being initialized with list of objects headed by 'empty choice'. There is no object with pk=0. In that form I have a clean() method:

def clean(self):
    if not Obj.objects.filter(self.cleaned.data['some_object'].exists():
        self.errors.update({'some_object': ['Invalid choice']})

It works well when I'm sending a form to a server, if data in it doesn't match conditions, field.is_valid returns False and I render form with error messages. But, when I create an empty form like this:

if request.method == 'GET':
    data = {'name': 'Untitled',
            'some_object': 0}
    form = MyForm(data)
    return render(request, 'app\template.html', {'form': form})

Django renders form with error message ('Invalid choice') even though form was just created and 'Object' select was intended to be set in empty position. Is it possible to disable form clean() method in specific cases? Or mayb

python django

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