From 49c4acefd087f4108b3574cd6af0a6946a029b38 Mon Sep 17 00:00:00 2001
From: Raphael Michel <mail@raphaelmichel.de>
Date: Mon, 10 Jun 2019 17:18:08 +0200
Subject: [PATCH] Fix critical error in previous commit

---
 src/pretix/api/views/event.py |  7 ++++---
 src/pretix/api/views/item.py  | 18 ++++++++++++------
 2 files changed, 16 insertions(+), 9 deletions(-)

diff --git a/src/pretix/api/views/event.py b/src/pretix/api/views/event.py
index 824923788..9dd95b0fd 100644
--- a/src/pretix/api/views/event.py
+++ b/src/pretix/api/views/event.py
@@ -244,13 +244,14 @@ class SubEventViewSet(ConditionalListView, viewsets.ModelViewSet):
         )
 
     def perform_update(self, serializer):
-        if serializer.data == self.get_serializer(instance=serializer.instance).data:
+        original_data = self.get_serializer(instance=serializer.instance).data
+        super().perform_update(serializer)
+
+        if serializer.data == original_data:
             # Performance optimization: If nothing was changed, we do not need to save or log anything.
             # This costs us a few cycles on save, but avoids thousands of lines in our log.
             return
 
-        super().perform_update(serializer)
-
         serializer.instance.log_action(
             'pretix.subevent.changed',
             user=self.request.user,
diff --git a/src/pretix/api/views/item.py b/src/pretix/api/views/item.py
index 97b149cc5..872db4969 100644
--- a/src/pretix/api/views/item.py
+++ b/src/pretix/api/views/item.py
@@ -65,11 +65,14 @@ class ItemViewSet(ConditionalListView, viewsets.ModelViewSet):
         return ctx
 
     def perform_update(self, serializer):
-        if serializer.data == self.get_serializer(instance=serializer.instance).data:
+        original_data = self.get_serializer(instance=serializer.instance).data
+
+        serializer.save(event=self.request.event)
+
+        if serializer.data == original_data:
             # Performance optimization: If nothing was changed, we do not need to save or log anything.
             # This costs us a few cycles on save, but avoids thousands of lines in our log.
             return
-        serializer.save(event=self.request.event)
         serializer.instance.log_action(
             'pretix.event.item.changed',
             user=self.request.user,
@@ -456,14 +459,17 @@ class QuotaViewSet(ConditionalListView, viewsets.ModelViewSet):
         return ctx
 
     def perform_update(self, serializer):
-        if serializer.data == self.get_serializer(instance=serializer.instance).data:
-            # Performance optimization: If nothing was changed, we do not need to save or log anything.
-            # This costs us a few cycles on save, but avoids thousands of lines in our log.
-            return
+        original_data = self.get_serializer(instance=serializer.instance).data
 
         current_subevent = serializer.instance.subevent
         serializer.save(event=self.request.event)
         request_subevent = serializer.instance.subevent
+
+        if serializer.data == original_data:
+            # Performance optimization: If nothing was changed, we do not need to save or log anything.
+            # This costs us a few cycles on save, but avoids thousands of lines in our log.
+            return
+
         serializer.instance.log_action(
             'pretix.event.quota.changed',
             user=self.request.user,