From 8c5a4dbe4118e4700ac88915d5e056efc910cada Mon Sep 17 00:00:00 2001
From: OlhaZahoruiko <olha@maykinmedia.nl>
Date: Thu, 5 Feb 2026 14:58:53 +0100
Subject: [PATCH] :bug: [#718] Fix 500 error on duplicate UUID when creating
 objects

---
 src/objects/api/serializers.py          | 14 +++++++++++--
 src/objects/tests/v2/test_validation.py | 28 +++++++++++++++++++++++++
 2 files changed, 40 insertions(+), 2 deletions(-)

diff --git a/src/objects/api/serializers.py b/src/objects/api/serializers.py
index 297463ab..e6f18a5b 100644
--- a/src/objects/api/serializers.py
+++ b/src/objects/api/serializers.py
@@ -3,6 +3,7 @@
 
 import structlog
 from rest_framework import serializers
+from rest_framework.validators import UniqueValidator
 from rest_framework_gis.serializers import GeometryField
 
 from objects.core.models import Object, ObjectRecord, ObjectType, Reference
@@ -102,7 +103,13 @@ class ObjectSerializer(DynamicFieldsMixin, serializers.HyperlinkedModelSerialize
     uuid = serializers.UUIDField(
         source="object.uuid",
         required=False,
-        validators=[IsImmutableValidator()],
+        validators=[
+            IsImmutableValidator(),
+            UniqueValidator(
+                queryset=Object.objects.all(),
+                message=_("An object with this UUID already exists."),
+            ),
+        ],
         help_text=_("Unique identifier (UUID4)"),
     )
     type = ObjectTypeField(
@@ -128,13 +135,16 @@ class Meta:
     @transaction.atomic
     def create(self, validated_data):
         object_data = validated_data.pop("object", {})
-        if object_type := validated_data.pop("_object_type"):
+
+        if object_type := validated_data.pop("_object_type", None):
             object_data["object_type"] = object_type
+
         object = Object.objects.create(**object_data)
 
         validated_data["object"] = object
         references = validated_data.pop("references", [])
         record = super().create(validated_data)
+
         Reference.objects.bulk_create(
             Reference(record=record, **ref_data) for ref_data in references
         )
diff --git a/src/objects/tests/v2/test_validation.py b/src/objects/tests/v2/test_validation.py
index afdaa70f..cfe22645 100644
--- a/src/objects/tests/v2/test_validation.py
+++ b/src/objects/tests/v2/test_validation.py
@@ -535,3 +535,31 @@ def test_update_geometry_not_allowed(self, m):
             response.json()["non_field_errors"],
             ["This object type doesn't support geometry"],
         )
+
+    def test_create_object_with_duplicate_uuid_returns_400(self, m):
+        mock_service_oas_get(m, OBJECT_TYPES_API, "objecttypes")
+        m.get(
+            f"{self.object_type.url}/versions/1",
+            json=mock_objecttype_version(self.object_type.url),
+        )
+
+        url = reverse("object-list")
+
+        data = {
+            "uuid": "11111111-1111-1111-1111-111111111111",
+            "type": self.object_type.url,
+            "record": {
+                "typeVersion": 1,
+                "data": {"diameter": 30},
+                "startAt": "2026-02-05",
+            },
+        }
+
+        response = self.client.post(url, data, **GEO_WRITE_KWARGS)
+        self.assertEqual(response.status_code, status.HTTP_201_CREATED)
+
+        response = self.client.post(url, data, **GEO_WRITE_KWARGS)
+        self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
+        self.assertEqual(
+            response.json()["uuid"], ["An object with this UUID already exists."]
+        )