Limit number of images user can upload - django

Question

I have a blog feature on my site, users can upload a single main image and multiple supporting images. The issue I am facing is I want to be able to limit the number of images a user can upload. I understand that I could use a for loop on it but if the user goes back later and adds more it would make the for loop useless. So I figured the best way to do this would be to add a field to the model that would count the number of images uploaded and then I can use an if statement to check if more than a said number of images have been uploaded. How would i go about getting the number of images and adding them to the post while it is being created. Or should I go about this a different way
view
#login_required
def createPostView(request):
currentUser = request.user
postForm = PostForm()
if request.method == 'POST':
postForm = PostForm(request.POST, request.FILES)
if postForm.is_valid():
PostFormID = postForm.save(commit=False)
PostFormID.author = request.user
PostFormID.save()
for f in request.FILES.getlist('images'):
test = PostImagesForm(request.POST, request.FILES)
if test.is_valid():
instance = test.save(commit=False)
instance.post_id = PostFormID.id
instance.images = f
instance.save()
return HttpResponseRedirect("/")
return render(request, 'blog/post_form.html', {'postForm': postForm, 'PostImagesForm':PostImagesForm})

Answer 1

You can check the total items in a list before looping by using len.
len(request.FILES.getlist('images'))
>>> 10
So something like:
if len(request.FILES.getlist('images')) > 3:
raise Exception("Only three images allowed")
else:
// process the images in the for loop