validate delete inline formset django
class RequiredImageInlineFormset(forms.models.BaseInlineFormSet):
""" Makes inline fields required """
def clean(self):
# get forms that actually have valid data
count = 0
delete_checked = 0
for form in self.forms:
try:
if form.cleaned_data:
count += 1
if form.cleaned_data['DELETE']:
delete_checked += 1
if not form.cleaned_data['DELETE']:
delete_checked -= 1
except AttributeError:
# annoyingly, if a subform is invalid Django explicity raises
# an AttributeError for cleaned_data
pass
# Case no images uploaded
if count < 1:
raise forms.ValidationError(
'At least one image is required.')
# Case one image added and another deleted
if delete_checked > 0 and ProductImage.objects.filter(product=self.instance).count() == 1:
raise forms.ValidationError(
"At least one image is required.")