Fixes: #266 - Handle nested serializers in create and update API methods

netbox_custom_objects/api/serializers.py

@@ -8,6 +8,7 @@
 from rest_framework import serializers
 from rest_framework.exceptions import ValidationError
 from rest_framework.reverse import reverse
+from rest_framework.utils import model_meta
 
 from netbox_custom_objects import field_types
 from netbox_custom_objects.models import (CustomObject, CustomObjectType,
@@ -253,6 +254,44 @@ def get_display(self, obj):
         """Get display representation of the object"""
         return str(obj)
 
+    # Stock DRF create() without raise_errors_on_nested_writes guard
+    def create(self, validated_data):
+        ModelClass = self.Meta.model
+
+        info = model_meta.get_field_info(ModelClass)
+        many_to_many = {}
+        for field_name, relation_info in info.relations.items():
+            if relation_info.to_many and (field_name in validated_data):
+                many_to_many[field_name] = validated_data.pop(field_name)
+
+        instance = ModelClass._default_manager.create(**validated_data)
+
+        if many_to_many:
+            for field_name, value in many_to_many.items():
+                field = getattr(instance, field_name)
+                field.set(value)
+
+        return instance
+
+    # Stock DRF update() with custom field.set() for M2M
+    def update(self, instance, validated_data):
+        info = model_meta.get_field_info(instance)
+
+        m2m_fields = []
+        for attr, value in validated_data.items():
+            if attr in info.relations and info.relations[attr].to_many:
+                m2m_fields.append((attr, value))
+            else:
+                setattr(instance, attr, value)
+
+        instance.save()
+
+        for attr, value in m2m_fields:
+            field = getattr(instance, attr)
+            field.set(value, clear=True)
+
+        return instance
+
     # Create basic attributes for the serializer
     attrs = {
         "Meta": meta,
@@ -261,6 +300,8 @@ def get_display(self, obj):
         "get_url": get_url,
         "display": serializers.SerializerMethodField(),
         "get_display": get_display,
+        "create": create,
+        "update": update,
     }
 
     for field in model_fields:

netbox_custom_objects/tests/base.py

@@ -96,7 +96,8 @@ def create_simple_custom_object_type(self, **kwargs):
 
         return custom_object_type
 
-    def create_complex_custom_object_type(self, **kwargs):
+    @classmethod
+    def create_complex_custom_object_type(cls, **kwargs):
         """Create a complex custom object type with various field types."""
         custom_object_type = CustomObjectsTestCase.create_custom_object_type(**kwargs)
         choice_set = CustomObjectsTestCase.create_choice_set()
@@ -149,6 +150,15 @@ def create_complex_custom_object_type(self, **kwargs):
             related_object_type=device_object_type
         )
 
+        # Multi-Object field (devices)
+        CustomObjectsTestCase.create_custom_object_type_field(
+            custom_object_type,
+            name="devices",
+            label="Devices",
+            type="multiobject",
+            related_object_type=device_object_type
+        )
+
         return custom_object_type
 
     def create_self_referential_custom_object_type(self, **kwargs):

netbox_custom_objects/tests/test_api.py

@@ -1,10 +1,14 @@
 from django.urls import reverse
 
-from users.models import Token
 from utilities.testing import APIViewTestCases, create_test_user
+from rest_framework import status
 
 from netbox_custom_objects.models import CustomObjectType
 from .base import CustomObjectsTestCase
+from core.models import ObjectType
+from dcim.models import Device, DeviceRole, DeviceType, Manufacturer, Rack, Site
+from users.models import ObjectPermission, Token
+from virtualization.models import Cluster, ClusterType
 
 
 class CustomObjectTest(CustomObjectsTestCase, APIViewTestCases.APIViewTestCase):
@@ -32,6 +36,72 @@ def setUp(self):
 
     @classmethod
     def setUpTestData(cls):
+        # Set up some devices to be used in object/multiobject fields
+        sites = (
+            Site(name='Site 1', slug='site-1'),
+            Site(name='Site 2', slug='site-2'),
+        )
+        Site.objects.bulk_create(sites)
+
+        racks = (
+            Rack(name='Rack 1', site=sites[0]),
+            Rack(name='Rack 2', site=sites[1]),
+        )
+        Rack.objects.bulk_create(racks)
+
+        manufacturer = Manufacturer.objects.create(name='Manufacturer 1', slug='manufacturer-1')
+
+        device_types = (
+            DeviceType(manufacturer=manufacturer, model='Device Type 1', slug='device-type-1'),
+            DeviceType(manufacturer=manufacturer, model='Device Type 2', slug='device-type-2', u_height=2),
+        )
+        DeviceType.objects.bulk_create(device_types)
+
+        roles = (
+            DeviceRole(name='Device Role 1', slug='device-role-1', color='ff0000'),
+            DeviceRole(name='Device Role 2', slug='device-role-2', color='00ff00'),
+        )
+        for role in roles:
+            role.save()
+
+        cluster_type = ClusterType.objects.create(name='Cluster Type 1', slug='cluster-type-1')
+
+        clusters = (
+            Cluster(name='Cluster 1', type=cluster_type),
+            Cluster(name='Cluster 2', type=cluster_type),
+        )
+        Cluster.objects.bulk_create(clusters)
+
+        devices = (
+            Device(
+                device_type=device_types[0],
+                role=roles[0],
+                name='Device 1',
+                site=sites[0],
+                rack=racks[0],
+                cluster=clusters[0],
+                local_context_data={'A': 1}
+            ),
+            Device(
+                device_type=device_types[0],
+                role=roles[0],
+                name='Device 2',
+                site=sites[0],
+                rack=racks[0],
+                cluster=clusters[0],
+                local_context_data={'B': 2}
+            ),
+            Device(
+                device_type=device_types[0],
+                role=roles[0],
+                name='Device 3',
+                site=sites[0],
+                rack=racks[0],
+                cluster=clusters[0],
+                local_context_data={'C': 3}
+            ),
+        )
+        Device.objects.bulk_create(devices)
 
         # Create test custom object types
         cls.custom_object_type1 = CustomObjectType.objects.create(
@@ -48,6 +118,8 @@ def setUpTestData(cls):
             slug="test-objects-2",
         )
 
+        cls.custom_object_type3 = cls.create_complex_custom_object_type(name="ComplexObject")
+
         cls.model = cls.custom_object_type1.get_model()
         cls.create_custom_object_type_field(cls.custom_object_type1)
 
@@ -103,6 +175,48 @@ def test_delete_object(self):
         # TODO: ObjectChange causes failure
         ...
 
+    def test_create_with_nested_serializers(self):
+        """
+        POST a single object with a multiobject field's values specified via a list of PKs.
+        """
+        model = self.custom_object_type3.get_model()
+
+        # Set the model for the test class
+        self.model = model
+
+        # Add object-level permission
+        obj_perm = ObjectPermission(
+            name='Test permission',
+            actions=['add']
+        )
+        obj_perm.save()
+        obj_perm.users.add(self.user)
+        obj_perm.object_types.add(ObjectType.objects.get_for_model(self.model))
+
+        devices = Device.objects.all()
+
+        data = {
+            'test_field': 'Test 004',
+            'device': devices[0].id,
+            'devices': [devices[1].id, devices[2].id],
+        }
+
+        initial_count = self._get_queryset().count()
+
+        viewname = 'plugins-api:netbox_custom_objects-api:customobject-list'
+        list_url = reverse(viewname, kwargs={'custom_object_type': self.custom_object_type3.slug})
+
+        response = self.client.post(list_url, data, format='json', **self.header)
+        self.assertHttpStatus(response, status.HTTP_201_CREATED)
+        self.assertEqual(self._get_queryset().count(), initial_count + 1)
+        instance = self._get_queryset().get(pk=response.data['id'])
+        self.assertInstanceEqual(
+            instance,
+            self.create_data[0],
+            exclude=self.validation_excluded_fields,
+            api=True
+        )
+
     # TODO: GraphQL
     def test_graphql_list_objects(self):
         ...