Django inlineformset_factory验证器不工作

Question

代码段

Django版本：3.1.7

型号.py

# custom validator
is_numeric = RegexValidator(r"^[0-9]*$", "Only numbers are allowed")
class Person(models.Model):
# all the boring fields

class PersonAddress(models.Model):
# all the boring fields
person = models.ForeignKey(
Person, null=True, on_delete=models.SET_NULL, related_name="person_address",
)
postcode = models.CharField(
blank=True, help_text="Include leading zero if exists",
max_length=10, validators=[is_numeric],
)

PersonAddress将是Person的内联集，因为一个人可以有多个地址

forms.py

class PersonForm(forms.ModelForm):
class Meta:
model = Person
fields = "__all__"
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
self.helper = FormHelper()

class PersonAddressForm(forms.ModelForm):
class Meta:
model = PersonAddress
fields = "__all__"
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
self.helper = FormHelper()
self.helper.form_method = "post"

PersonAddressFormSet = forms.models.inlineformset_factory(
Person, PersonAddress, form=PersonAddressForm, extra=1, can_delete=True,
)
# min_num, validate_min don't help even though I read from other stackoverflow solution
# PersonAddressFormSet = forms.models.inlineformset_factory(
#     Person, PersonAddress, form=PersonAddressForm, extra=1, can_delete=True, min_num=1, validate_min=True,
# )

views.py

# Person CreateView
class PersonCreateView(SuccessMessageMixin, LoginRequiredMixin, CreateView):
model = Person
form_class = PersonForm
def get_context_data(self, **kwargs):
context = super(PersonCreateView, self).get_context_data(**kwargs)
if self.request.POST:
context["addresses"] = PersonAddressFormSet(self.request.POST, self.request.FILES)
else:
context["addresses"] = PersonAddressFormSet()
return context
# I think the problem is here, not 100% sure
def form_valid(self, form):
context = self.get_context_data()
addresses = context["addresses"]
self.object = form.save()
if addresses.is_valid():
addresses.instance = self.object
addresses.save()
# https://stackoverflow.com/questions/47476941/django-inlineformset-factory-error-messages-not-working
# my attempt, got this error
# TypeError: join() argument must be str, bytes, or os.PathLike object, not 'NoneType'
# else:
#    return render(self.request, self.template_name, context)
return super(PersonCreateView, self).form_valid(form)

# PersonAddress CreateView
class PersonAddressCreateView(SuccessMessageMixin, LoginRequiredMixin, CreateView):
model = PersonAddress
form_class = PersonAddressForm

问题

如果使用非数字字符串的postcode创建PersonAddress对象，则PersonAddressCreateViewHTML表单将返回验证错误。

但如果我在PersonCreateViewHTML表单中做同样的事情，就不会有任何验证错误。将创建Person对象，不会创建PersonAddress，因为postcode无效。我所期望的是PersonCreateViewHTML表单向我显示验证错误，而不是保存表单。

我认为解决方案应该和PersonCreateView的form_valid有关，但我不确定。

提前感谢！

Answer 1

实际上，问题出在form_valid实现中。确切地说，当PersonAddressFormSet无效时，您只是无所事事。要解决该问题，请尝试：

def form_valid(self, form):
context = self.get_context_data()
addresses = context["addresses"]
self.object = form.save()
if addresses.is_valid():
addresses.instance = self.object
addresses.save()
else:
return self.form_invalid(form)
return super(PersonCreateView, self).form_valid(form)