Django ValueError '没有返回 HttpResponse 对象'

Question

I have just started learning Python and Django. I was trying to create a simple blog website and ran into this error while updating the post. Django gives me this error when I try to update the post. Everything else seems to be working fine and I can update the post from admin.

Error: ValueError at /post/4/ The view posts.views.PostDetailView didn't return an HttpResponse object. It returned None instead.

Here is my code for the UpdateViews.py

class PostUpdateView(LoginRequiredMixin, UserPassesTestMixin, UpdateView):
model = Post
form_class = PostForm

def form_valid(self,form):
    form.instance.author = self.request.user
    return super().form_valid(form)

def test_func(self):
    post=self.get_object()
    if self.request.user == post.Author:
        return True
    return False

Here is my code for DetailView:

class PostDetailView(DetailView):
model = Post
template_name = 'posts/post.html'
context_object_name = 'obj'
form = CommentForm

def get_object(self):
    obj = super().get_object()
    if self.request.user.is_authenticated:
        PostView.objects.get_or_create(user=self.request.user,post=obj)
    return obj

def get_context_data(self, *args, **kwargs):
    CatCount = Category_Count()
    context = super().get_context_data(*args, **kwargs)
    context['latest'] = Post.objects.order_by('-date_added')[0:3]
    context['Category_Count'] = CatCount
    context['form'] = self.form
    return context

def post(self, request, *args, **kwargs):
    form = CommentForm(request.POST)
    if form.is_valid():
        post = self.get_object()
        form.instance.Author = request.user
        form.instance.post = post
        form.save()
        return redirect(reverse("post", kwargs={
        'pk': post.pk
        }))

I have no idea why it's returning me this error, so any solution would be appreciated. Thank You in Advance.

Answer 1

You don't return anything when the form is not valid. You can render the template again with the form that contains the errors:

class PostDetailView(DetailView):
    model = Post
    template_name = 'posts/post.html'
    context_object_name = 'obj'
    form = CommentForm

    # …

    def post(self, request, *args, **kwargs):
        form = CommentForm(request.POST)
        if form.is_valid():
            post = self.get_object()
            form.instance.Author = request.user
            form.instance.post = post
            form.save()
            return redirect('post', pk=post.pk)
        self.object = self.get_object()
        context = self.get_context_data(object=self.object)
        return