Remove created object if user doesn't confirmed it in current session - django

Question

I have a form on web page where an authenticated user can create an order. When they create the order, they are redirected to order_review page. On the order_review page, there is a confirm button and cancel button.
If cancel button is clicked, order is removed. But I can't rely on that user either clicks on confirm or cancel so I would like to handle situations when user leaves this page.
There are two ways in my opinion. Either the order would be deleted when users session expired or when it wasn't confirmed for for example 5 minutes.
def reviewOrder(request, id):
order = get_object_or_404(models.Order, id=id)
if order.type == 'retail':
total = models.Price.calculate_price(order.dry_wood, order.wet_wood, order.briquette, order.stelinka)
context = {'order': order}
context.update(total)
return render(request, 'reviewOrder.html', context=context)
return render(request, 'reviewOrder.html', context={'order': order})
def delete_order(request, id):
order = get_object_or_404(models.Order, id=id)
order.delete()
return HttpResponseRedirect('/')
def confirm_order(request, id):
order = get_object_or_404(models.Order, id=id)
order.confirmed = True
order.save()
if not order.backuped:
models.OrderBackup.objects.create(original_id=order.id,**model_to_dict(order, exclude=['id','customer','backuped' ]))
order.backuped = True
notifications.AdminNotifications.new_order(order)
notifications.CustomerNotifications.orderHasBeenCreated(order)
return HttpResponseRedirect('/')
What would you do?

Answer 1

So one way I've handled this before is to use onbeforeunload (in conjunction with other methods). The idea is to fire off an ajax call to some url in your website that will handle things as the user leaves the current page.
window.onbeforeunload = function(e) {
$.ajax({
url: "/remove_order/",
type: "post",
async: false,
data:{
'orer_id':order_id
}
});
return undefined;
};
So when the user leaves the page by clicking a link or typing a new url it will fire off this ajax call to remove the order or it can check the current state of the order and then do what you need etc.
I last used this to decrement some inventory in a system when it was temporarily taken this helped to free up inventory immediately in most cases but i also had a periodic task that would cleanup unused inventory after some time.
I've had things clean up on session end or another way I've done this before is to use http://www.celeryproject.org/celery task queues and fire off an async task after a period of time
cleanup_stuff.apply_async((somemodel.id,), countdown=timedelta(minutes=15).seconds)
#classmethod
def cleanup_stuff(cls, id=None):
# blah blah create conditions for deletion
cls.objects.filter(*conditions).delete()