Django - ModelForm Dynamic field update

Question

I\'m trying to update certain fields a ModelForm, these fields are not fixed. (I have only tutor that is autopopulated by the view)

Model:

Answer 1

Put your form fields as nullable and with "clean" methods you can add logic to fields ex:

class SessionForm(forms.ModelForm):
    def clean_end_date(self):
        cd = self.cleaned_data
        if (cd["start_date"] and cd["end_date"]) and cd["end_date"] < cd["start_date"]:
            raise forms.ValidationError("WTF?!")
        if not (cd["start_date"] or cd["end_date"]):
            raise forms.ValidationError("need one date")
        return cd['end_date']

If you want to change value, use a different value to the return statement.

This is what you may need for validation.

If you want, you may copy GET dictionary in your view and update values before instanciate your form

def my_view(request):
    r_data = request.GET.copy()
    r_data.merge(request.POST)

    data = dict([(key, my_function(key, value)) for key, value in r_data.iteritems() if key in MyForm.fields])
    form = MyForm(data=data)
    [...]

hopes it help.