Fixes #16624: Set allow_null=True on method fields that can return None

netbox/dcim/api/serializers_/base.py

@@ -13,7 +13,7 @@ class ConnectedEndpointsSerializer(serializers.ModelSerializer):
     """
     Legacy serializer for pre-v3.3 connections
     """
-    connected_endpoints_type = serializers.SerializerMethodField(read_only=True)
+    connected_endpoints_type = serializers.SerializerMethodField(read_only=True, allow_null=True)
     connected_endpoints = serializers.SerializerMethodField(read_only=True)
     connected_endpoints_reachable = serializers.SerializerMethodField(read_only=True)
 
@@ -22,7 +22,7 @@ def get_connected_endpoints_type(self, obj):
         if endpoints := obj.connected_endpoints:
             return f'{endpoints[0]._meta.app_label}.{endpoints[0]._meta.model_name}'
 
-    @extend_schema_field(serializers.ListField)
+    @extend_schema_field(serializers.ListField(allow_null=True))
     def get_connected_endpoints(self, obj):
         """
         Return the appropriate serializer for the type of connected object.

netbox/dcim/api/serializers_/cables.py

@@ -91,7 +91,7 @@ def get_path(self, obj):
 class CabledObjectSerializer(serializers.ModelSerializer):
     cable = CableSerializer(nested=True, read_only=True, allow_null=True)
     cable_end = serializers.CharField(read_only=True)
-    link_peers_type = serializers.SerializerMethodField(read_only=True)
+    link_peers_type = serializers.SerializerMethodField(read_only=True, allow_null=True)
     link_peers = serializers.SerializerMethodField(read_only=True)
     _occupied = serializers.SerializerMethodField(read_only=True)
 

netbox/dcim/api/serializers_/devices.py

@@ -88,7 +88,7 @@ class Meta:
         ]
         brief_fields = ('id', 'url', 'display', 'name', 'description')
 
-    @extend_schema_field(NestedDeviceSerializer)
+    @extend_schema_field(NestedDeviceSerializer(allow_null=True))
     def get_parent_device(self, obj):
         try:
             device_bay = obj.parent_bay

netbox/extras/api/serializers_/scripts.py

@@ -39,7 +39,7 @@ def get_vars(self, obj):
     def get_display(self, obj):
         return f'{obj.name} ({obj.module})'
 
-    @extend_schema_field(serializers.CharField())
+    @extend_schema_field(serializers.CharField(allow_null=True))
     def get_description(self, obj):
         if obj.python_class:
             return obj.python_class().description