Always make explicit which tables to lock (#3058)

Co-authored-by: Richard Schreiber <schreiber@rami.io>

src/pretix/api/middleware.py

@@ -32,6 +32,7 @@ from rest_framework import status
 
 from pretix.api.models import ApiCall
 from pretix.base.models import Organizer
+from pretix.helpers import OF_SELF
 
 
 class IdempotencyMiddleware:
@@ -56,7 +57,7 @@ class IdempotencyMiddleware:
         idempotency_key = request.headers.get('X-Idempotency-Key', '')
 
         with transaction.atomic():
-            call, created = ApiCall.objects.select_for_update().get_or_create(
+            call, created = ApiCall.objects.select_for_update(of=OF_SELF).get_or_create(
                 auth_hash=auth_hash,
                 idempotency_key=idempotency_key,
                 defaults={

src/pretix/api/views/organizer.py

@@ -51,6 +51,7 @@ from pretix.base.models import (
     User,
 )
 from pretix.base.settings import SETTINGS_AFFECTING_CSS
+from pretix.helpers import OF_SELF
 from pretix.helpers.dicts import merge_dicts
 from pretix.presale.style import regenerate_organizer_css
 
@@ -178,7 +179,7 @@ class GiftCardViewSet(viewsets.ModelViewSet):
     def perform_update(self, serializer):
         if 'include_accepted' in self.request.GET:
             raise PermissionDenied("Accepted gift cards cannot be updated, use transact instead.")
-        GiftCard.objects.select_for_update().get(pk=self.get_object().pk)
+        GiftCard.objects.select_for_update(of=OF_SELF).get(pk=self.get_object().pk)
         old_value = serializer.instance.value
         value = serializer.validated_data.pop('value')
         inst = serializer.save(secret=serializer.instance.secret, currency=serializer.instance.currency,
@@ -196,7 +197,7 @@ class GiftCardViewSet(viewsets.ModelViewSet):
     @action(detail=True, methods=["POST"])
     @transaction.atomic()
     def transact(self, request, **kwargs):
-        gc = GiftCard.objects.select_for_update().get(pk=self.get_object().pk)
+        gc = GiftCard.objects.select_for_update(of=OF_SELF).get(pk=self.get_object().pk)
         value = serializers.DecimalField(max_digits=10, decimal_places=2).to_internal_value(
             request.data.get('value')
         )

src/pretix/api/webhooks.py

@@ -42,6 +42,7 @@ from pretix.base.models import LogEntry
 from pretix.base.services.tasks import ProfiledTask, TransactionAwareTask
 from pretix.base.signals import periodic_task
 from pretix.celery_app import app
+from pretix.helpers import OF_SELF
 
 logger = logging.getLogger(__name__)
 _ALL_EVENTS = None
@@ -502,7 +503,8 @@ def manually_retry_all_calls(webhook_id: int):
         webhook = WebHook.objects.get(id=webhook_id)
     with scope(organizer=webhook.organizer), transaction.atomic():
         for whcr in webhook.retries.select_for_update(
-            skip_locked=connection.features.has_select_for_update_skip_locked
+            skip_locked=connection.features.has_select_for_update_skip_locked,
+            of=OF_SELF
         ):
             send_webhook.apply_async(
                 args=(whcr.logentry_id, whcr.action_type, whcr.webhook_id, whcr.retry_count),
@@ -515,7 +517,8 @@ def manually_retry_all_calls(webhook_id: int):
 def schedule_webhook_retries_on_celery(sender, **kwargs):
     with transaction.atomic():
         for whcr in WebHookCallRetry.objects.select_for_update(
-            skip_locked=connection.features.has_select_for_update_skip_locked
+            skip_locked=connection.features.has_select_for_update_skip_locked,
+            of=OF_SELF
         ).filter(retry_not_before__lt=now()):
             send_webhook.apply_async(
                 args=(whcr.logentry_id, whcr.action_type, whcr.webhook_id, whcr.retry_count),