Solution 1 :

JsonResponse by default expect to return a Json Dict. Using: safe=False you override this behavior telling that it’s OK to return a non dict object.

Your problem is that in this line:

    return response.json()

Your JS code wait as well for a dict.

So you have to pass a JsonDict in the response and JS will be able to parse it

Problem :

I have a simple add and remove button for a cart, but whenever i click on the button, i get an error in the console, please bear in mind, i a newbie:

cart.js:25 POST 404 (Not Found)
updateUserOrder @ cart.js:25
(anonymous) @ cart.js:14 Uncaught (in promise) SyntaxError: Unexpected token < in JSON at position 0

And this is the error i get in my terminal:

Not Found: /update_item/

I strongly feel this is the problem, as the fetch is not recognizing update_item in

This is the code in cart.js:

function updateOrder (ticketId, action){
console.log('User is logged in, sending data..')

var url = '/update_item/'

fetch(url, {
        'X-CSRFToken': csrftoken,
    body:JSON.stringify({'ticketId': ticketId, 'action':action})

.then((response) =>{
    return response.json()
.then((data) =>{
    console.log('data:', data)


This is my code:

def updateItem(request):
data = json.loads(request.body)
ticketId = data['ticketId']
action = data['action']

print('Action:', action)
print('ticketId:', ticketId)

customer = request.user.customer
ticket = Ticket.objects.get(id=ticketId)
order, created = Order.objects.get_or_create(customer=customer, complete=False)

orderItem, created = OrderItem.objects.get_or_create(order=order, ticket=ticket)

if action == 'add':
    orderItem.quantity = (orderItem.quantity + 1)
elif action == 'remove':
    orderItem.quantity = (orderItem.quantity - 1)

if orderItem.quantity <= 0:

return JsonResponse('Item was added', safe=False)


Comment posted by Beulah Akindele

Where is the rest of your URL?

Comment posted by Nelson Kehinde

This is it path(‘checkout/’, views.checkout, name=”checkout”), path(‘update_item/’, views.updateItem, name=”update_item”),

Comment posted by 420root

If you are not going to use the Json properly in the response but to console.log a success message, probably the straigth forward way: not return a Jsonresponse from views and use a string in JS to return that messagge.

Comment posted by Nelson Kehinde

I have that so that i know it worked. But it not working

Comment posted by Nelson Kehinde

Thank you for your response, this is what i have:

Comment posted by Tartempion34

As I said response.json wait for a dictionnary not a string. like {‘status’:’ok’} this is a json dictionnary