Django 1.11-CreateView-无效的表单针对不存在的对象属性引发错误

Question

Django 1.11, using generic class based views.

When submitting an invalid form then the call super(CreateSupport, self).get_context_data(**kwargs) raises

AttributeError: 'CreateSupport' object has no attribute 'object'.

Expecting to show validation errors on form instead.

View/Create when form is valid works alright.

This is the class:

class CreateSupport(IsAdminMixin, CreateView):
model = Support
form_class = SupportForm
template_name = 'admin/support/form.html'
success_url = reverse_lazy('admin-supports')

def get_context_data(self, **kwargs):
    context = super(CreateSupport, self).get_context_data(**kwargs)
    if hasattr(self, 'object'):
        context['images_form'] = SupportForm.ProductImageFormSet(
            instance=self.object) if "validated_images_form" not in kwargs else kwargs["validated_images_form"]

    # filter the colour and size options for current vendor
    curr_vend = Vendor.objects.get(id=self.kwargs['vendorid'])
    context['colours'] = Colour.objects.filter(vendor=curr_vend)
    context['sizes'] = Size.objects.filter(vendor=curr_vend)
    return context

def form_valid(self, support_form):
    if support_form.is_valid():
        redirect = super(CreateSupport, self).form_valid(support_form)
    else:
        validated_forms_context = self.get_context_data(form=support_form)
        redirect = self.render_to_response(validated_forms_context)

    return redirect

def post(self, request, *args, **kwargs):
    support_form = SupportForm(data=request.POST)
    return self.form_valid(support_form)

I could not find any solution to this so far other than this old post using self.get_object() method that obviously would not work since the object has not yet been created.

Traceback:

"C:\Program Files\JetBrains\PyCharm 2017.3.3\helpers\pydev\_pydevd_bundle\pydevd_exec2.py", line 3, in Exec
    exec(exp, global_vars, local_vars)
  File "<input>", line 1, in <module>
  File "C:\ProgramData\Anaconda2\envs\django3.4\lib\site-packages\django\views\generic\edit.py", line 94, in get_context_data
    return super(FormMixin, self).get_context_data(**kwargs)
  File "C:\ProgramData\Anaconda2\envs\django3.4\lib\site-packages\django\views\generic\detail.py", line 101, in get_context_data
    if self.object:
AttributeError: 'CreateSupport' object has no attribute 'object'

Answer 1

Following Will Keeling's comment about the default post() implementation, I reached out to BaseCreateView class.

This is the default implementation of post():

def post(self, request, *args, **kwargs):
    self.object = None
    return super(BaseCreateView, self).post(request, *args, **kwargs)

The problem can thus be simply resolved by setting the self.object to None.