Optimize multibuy database queries

stregsystem/models.py

@@ -129,15 +129,15 @@ def execute(self):
         self.member = Member.objects.select_for_update().get(id=self.member.id)
         self.member.fulfill(transaction)
 
+        # Collect all the sales of the order
+        sales = []
         for item in self.items:
-            # @HACK Since we want to use the old database layout, we need to
-            # add a sale for every item and every instance of that item
             for i in range(item.count):
                 s = Sale(member=self.member, product=item.product, room=self.room, price=item.product.price)
-                s.save()
+                sales.append(s)
+        # Save all the sales
+        Sale.objects.bulk_create(sales)
 
-            # Bought (used above) is automatically calculated, so we don't need
-            # to update it
         # We changed the user balance, so save that
         self.member.save()
 

stregsystem/views.py

@@ -163,19 +163,18 @@ def sale(request, room_id):
 
 def _multibuy_hint(now, member):
     # Get a timestamp to fetch sales for the member for the last 60 sec
-    earliest_recent_purchase = now - datetime.timedelta(seconds=60)
+    earliest_recent_sale = now - datetime.timedelta(seconds=60)
     # get the sales with this timestamp
-    recent_purchases = Sale.objects.filter(member=member, timestamp__gt=earliest_recent_purchase)
-    number_of_recent_distinct_purchases = recent_purchases.values('timestamp').distinct().count()
+    recent_sales = Sale.objects.filter(member=member, timestamp__gt=earliest_recent_sale)
+    number_of_recent_distinct_sales = recent_sales.values('timestamp').distinct().count()
+    recent_unique_sales = recent_sales.values('product').distinct().annotate(total=Count('product'))
 
     # add hint for multibuy
-    if number_of_recent_distinct_purchases > 1:
+    if number_of_recent_distinct_sales > 1:
         sale_dict = {}
-        for sale in recent_purchases:
-            if not str(sale.product.id) in sale_dict:
-                sale_dict[str(sale.product.id)] = 1
-            else:
-                sale_dict[str(sale.product.id)] = sale_dict[str(sale.product.id)] + 1
+        for unique_sale in recent_unique_sales:
+            sale_dict[str(unique_sale['product'])] = unique_sale['total']
+
         sale_hints = ["<span class=\"username\">{}</span>".format(member.username)]
         if all(sale_count == 1 for sale_count in sale_dict.values()):
             return (False, None)
@@ -889,16 +888,25 @@ def api_quicksale(request, room, member: Member, bought_ids):
 
 def __append_bought_ids_to_product_list(products, bought_ids, time_now, room):
     try:
-        for i in bought_ids:
+        # Get the amount of unique items bought
+        unique_product_dict = {}
+        for unique_id in bought_ids:
+            if unique_id not in unique_product_dict:
+                unique_product_dict[unique_id] = 1
+            else:
+                unique_product_dict[unique_id] += 1
+
+        # Add the given amount of different products
+        for key, value in unique_product_dict.items():
             product = Product.objects.get(
-                Q(pk=i),
+                Q(pk=key),
                 Q(active=True),
                 Q(deactivate_date__gte=time_now) | Q(deactivate_date__isnull=True),
                 Q(rooms__id=room.id) | Q(rooms=None),
             )
-            products.append(product)
+            products.extend([product for _ in range(value)])
     except Product.DoesNotExist:
-        return "Invalid product id", 400, i
+        return "Invalid product id", 400, key
     return "OK", 200, None