From 245fb48989e3c53c023ecb9b0e2cb11786a3d7f9 Mon Sep 17 00:00:00 2001
From: Richard Schreiber <schreiber@rami.io>
Date: Fri, 28 Nov 2025 15:25:11 +0100
Subject: [PATCH] update media-API

---
 src/pretix/api/serializers/media.py | 31 +++++++++++++++++++++++++----
 src/pretix/api/views/media.py       |  8 +++++---
 2 files changed, 32 insertions(+), 7 deletions(-)

diff --git a/src/pretix/api/serializers/media.py b/src/pretix/api/serializers/media.py
index 8285fade48..cbfcbcf295 100644
--- a/src/pretix/api/serializers/media.py
+++ b/src/pretix/api/serializers/media.py
@@ -76,10 +76,21 @@ class ReusableMediaSerializer(I18nAwareModelSerializer):
                 queryset=self.context['organizer'].issued_gift_cards.all()
             )
 
-        if 'linked_orderposition' in self.context['request'].query_params.getlist('expand'):
-            self.fields['linked_orderposition'] = NestedOrderPositionSerializer(read_only=True)
+        # keep linked_orderposition (singular) for backwards compatibility, will be overwritten in self.validate
+        self.fields['linked_orderposition'] = serializers.PrimaryKeyRelatedField(
+            required=False,
+            allow_null=True,
+            queryset=OrderPosition.all.filter(order__event__organizer=self.context['organizer']),
+        )
+
+        if 'linked_orderposition' in self.context['request'].query_params.getlist('expand') or 'linked_orderpositions' in self.context['request'].query_params.getlist('expand'):
+            self.fields['linked_orderpositions'] = NestedOrderPositionSerializer(
+                many=True,
+                read_only=True
+            )
         else:
-            self.fields['linked_orderposition'] = serializers.PrimaryKeyRelatedField(
+            self.fields['linked_orderpositions'] = serializers.PrimaryKeyRelatedField(
+                many=True,
                 required=False,
                 allow_null=True,
                 queryset=OrderPosition.all.filter(order__event__organizer=self.context['organizer']),
@@ -97,6 +108,10 @@ class ReusableMediaSerializer(I18nAwareModelSerializer):
 
     def validate(self, data):
         data = super().validate(data)
+                    'linked_orderposition': _('There are more than one linked_orderposition. You need to use linked_orderpositions.')
+                })
+            data['linked_orderpositions'] = [linked_orderposition]
+
         if 'type' in data and 'identifier' in data:
             qs = self.context['organizer'].reusable_media.filter(
                 identifier=data['identifier'], type=data['type']
@@ -109,6 +124,14 @@ class ReusableMediaSerializer(I18nAwareModelSerializer):
                 )
         return data
 
+    def to_representation(self, obj):
+        r = super(ReusableMediaSerializer, self).to_representation(obj)
+        ops = r.get('linked_orderpositions')
+        if len(ops) < 2:
+            # add linked_orderposition (singular) for backwards compatibility
+            r['linked_orderposition'] = ops[0] if ops else None
+        return r
+
     class Meta:
         model = ReusableMedium
         fields = (
@@ -121,7 +144,7 @@ class ReusableMediaSerializer(I18nAwareModelSerializer):
             'active',
             'expires',
             'customer',
-            'linked_orderposition',
+            'linked_orderpositions',
             'linked_giftcard',
             'info',
             'notes',
diff --git a/src/pretix/api/views/media.py b/src/pretix/api/views/media.py
index 1569ee2895..8b16a44da7 100644
--- a/src/pretix/api/views/media.py
+++ b/src/pretix/api/views/media.py
@@ -53,10 +53,12 @@ with scopes_disabled():
         customer = django_filters.CharFilter(field_name='customer__identifier')
         updated_since = django_filters.IsoDateTimeFilter(field_name='updated', lookup_expr='gte')
         created_since = django_filters.IsoDateTimeFilter(field_name='created', lookup_expr='gte')
+        # backwards-compatible
+        linked_orderposition = django_filters.NumberFilter(field_name='linked_orderpositions__id')
 
         class Meta:
             model = ReusableMedium
-            fields = ['identifier', 'type', 'active', 'customer', 'linked_orderposition', 'linked_giftcard']
+            fields = ['identifier', 'type', 'active', 'customer', 'linked_orderpositions', 'linked_giftcard']
 
 
 class ReusableMediaViewSet(viewsets.ModelViewSet):
@@ -75,7 +77,7 @@ class ReusableMediaViewSet(viewsets.ModelViewSet):
         ).order_by().values('card').annotate(s=Sum('value')).values('s')
         return self.request.organizer.reusable_media.prefetch_related(
             Prefetch(
-                'linked_orderposition',
+                'linked_orderpositions',
                 queryset=OrderPosition.objects.select_related(
                     'order', 'order__event', 'order__event__organizer', 'seat',
                 ).prefetch_related(
@@ -155,7 +157,7 @@ class ReusableMediaViewSet(viewsets.ModelViewSet):
                         type=s.validated_data["type"],
                         identifier=s.validated_data["identifier"],
                     )
-                m.linked_orderposition = None  # not relevant for cross-organizer
+                m.linked_orderpositions = None  # not relevant for cross-organizer
                 m.customer = None  # not relevant for cross-organizer
                 s = self.get_serializer(m)
                 return Response({"result": s.data})