NoReverseMatch Django: can't find pattern - django

Question

I'm building my first application (guess app) with Django, I've been doing well so far. But I've encountered an error when trying to redirect to a Detail View when a user submits a file through a submit function (similar to a 'post blog' scenario).
I've looked up several posts with the same problem and I can not figure out why my code is not working.
views.py
#login_required
def submit(request):
if request.method == 'POST':
submited_form = SubmitFileForm(request.POST, request.FILES)
if submited_form.is_valid():
...
form.save()
return HttpResponseRedirect(reverse('result-detail'), kwargs={'pk': form.pk})
else:
submited_form = SubmitFileForm()
return render(request, 'guess/submit.html', context)
class ResultDetailView(LoginRequiredMixin, DetailView):
model = Result
template_name = 'guess/result_detail.html'
context_object_name = 'result'
I know I'm mixing class based views with function based views, but for some reason I can not get my submit function to work when I try to implement it as a class based view. Anyway, I think that shouldn't be a problem
urls.py
url_patterns = [
...
path('result/<int:pk>', guess_views.ResultDetailView.as_view(), name='result-detail'),
...
]
result_detail.html
{% extends "guess/base.html" %}
{% block content %}
<article class="media content-section">
<div class="media-body">
<div class="article-metadata">
<a class="mr-2" href="#">{{ result.author }}</a>
<small class="text-muted">{{ result.date_posted }}</small>
</div>
<h2 class="article-title">{{ result.title }}</h2>
<p class="article-content">{{ result.statistic }}</p>
</div>
</article>
{% endblock content %}
I'd expect a redirect to the detail view of the object that has been created with the submit function and submitfileform (model form). I can access the details if I just type /result/ and the primary key of any created object. But apparently I can't do the same through a redirect.
The error I am getting:
NoReverseMatch at /submit/
Reverse for 'result-detail' with no arguments not found. 1 pattern(s) tried: ['result/(?P<pk>[0-9]+)$']

Answer 1

In your code, you have two problems. First, form is not a Model instance. When you call form.save(), it will return the model instance. So you need to store it in a variable. Second problem is that, you need to pass the kwargs as a known argument in the reverse, not in HttpResponseRedirect. So the following code should work:
instance = form.save()
return HttpResponseRedirect(reverse('result-detail',kwargs={'pk': instance.pk}))