Enabled asynchronous cart/order actions

src/pretix/presale/views/cart.py

@@ -1,13 +1,15 @@
 from django.contrib import messages
 from django.core.urlresolvers import reverse
+from django.http import JsonResponse
 from django.shortcuts import redirect
-from django.utils.translation import ugettext_lazy as _
+from django.utils.translation import ugettext as _
 from django.views.generic import View
 
 from pretix.base.services.cart import (
     CartError, add_items_to_cart, remove_items_from_cart,
 )
 from pretix.presale.views import EventViewMixin
+from pretix.presale.views.async import AsyncAction
 
 
 class CartActionMixin:
@@ -15,18 +17,16 @@ class CartActionMixin:
     def get_next_url(self):
         if "next" in self.request.GET and '://' not in self.request.GET:
             return self.request.GET.get('next')
-        elif "HTTP_REFERER" in self.request.META:
-            return self.request.META.get('HTTP_REFERER')
         else:
             return reverse('presale:event.index', kwargs={
                 'event': self.request.event.slug,
                 'organizer': self.request.event.organizer.slug,
             })
 
-    def get_success_url(self):
+    def get_success_url(self, value=None):
         return self.get_next_url()
 
-    def get_failure_url(self):
+    def get_error_url(self):
         return self.get_next_url()
 
     def _items_from_post_data(self):
@@ -61,27 +61,34 @@ class CartRemove(EventViewMixin, CartActionMixin, View):
     def post(self, *args, **kwargs):
         items = self._items_from_post_data()
         if not items:
-            return redirect(self.get_failure_url())
+            return redirect(self.get_error_url())
 
         remove_items_from_cart(self.request.event.identity, items, self.request.session.session_key)
         messages.success(self.request, _('Your cart has been updated.'))
         return redirect(self.get_success_url())
 
 
-class CartAdd(EventViewMixin, CartActionMixin, View):
+class CartAdd(EventViewMixin, CartActionMixin, AsyncAction, View):
+    task = add_items_to_cart
 
-    def __init__(self, *args, **kwargs):
-        super().__init__(*args, **kwargs)
+    def get_success_message(self, value):
+        return _('The products have been successfully added to your cart.')
+
+    def get_error_message(self, exception):
+        if isinstance(exception, dict) and exception['exc_type'] == 'CartError':
+            return exception['exc_message']
+        elif isinstance(exception, CartError):
+            return str(exception)
+        return super().get_error_message(exception)
 
     def post(self, request, *args, **kwargs):
         items = self._items_from_post_data()
-        return self.process(items)
-
-    def process(self, items):
-        try:
-            add_items_to_cart(self.request.event.identity, items, self.request.session.session_key)
-            messages.success(self.request, _('The products have been successfully added to your cart.'))
-            return redirect(self.get_success_url())
-        except CartError as e:
-            messages.error(self.request, str(e))
-            return redirect(self.get_failure_url())
+        if items:
+            return self.do(self.request.event.identity, items, self.request.session.session_key)
+        else:
+            if 'ajax' in self.request.GET or 'ajax' in self.request.POST:
+                return JsonResponse({
+                    'redirect': self.get_error_url()
+                })
+            else:
+                return redirect(self.get_error_url())