Fixes #2358: Respect custom field default values when creating objects via the REST API

docs/release-notes/version-2.6.md

@@ -8,6 +8,7 @@
 ## Bug Fixes
 
 * [#2170](https://github.com/netbox-community/netbox/issues/2170) - Prevent the deletion of a virtual chassis when a cross-member LAG is present
+* [#2358](https://github.com/netbox-community/netbox/issues/2358) - Respect custom field default values when creating objects via the REST API
 * [#3749](https://github.com/netbox-community/netbox/issues/3749) - Fix exception on password change page for local users
 
 # v2.6.8 (2019-12-10)

netbox/extras/api/customfields.py

@@ -22,7 +22,9 @@ class CustomFieldsSerializer(serializers.BaseSerializer):
     def to_internal_value(self, data):
 
         content_type = ContentType.objects.get_for_model(self.parent.Meta.model)
-        custom_fields = {field.name: field for field in CustomField.objects.filter(obj_type=content_type)}
+        custom_fields = {
+            field.name: field for field in CustomField.objects.filter(obj_type=content_type)
+        }
 
         for field_name, value in data.items():
 
@@ -107,11 +109,11 @@ class CustomFieldModelSerializer(ValidatedModelSerializer):
 
         super().__init__(*args, **kwargs)
 
-        if self.instance is not None:
+        # Retrieve the set of CustomFields which apply to this type of object
+        content_type = ContentType.objects.get_for_model(self.Meta.model)
+        fields = CustomField.objects.filter(obj_type=content_type)
 
-            # Retrieve the set of CustomFields which apply to this type of object
-            content_type = ContentType.objects.get_for_model(self.Meta.model)
-            fields = CustomField.objects.filter(obj_type=content_type)
+        if self.instance is not None:
 
             # Populate CustomFieldValues for each instance from database
             try:
@@ -120,6 +122,23 @@ class CustomFieldModelSerializer(ValidatedModelSerializer):
             except TypeError:
                 _populate_custom_fields(self.instance, fields)
 
+        else:
+
+            # Populate default values
+            if fields and 'custom_fields' not in self.initial_data:
+                self.initial_data['custom_fields'] = {}
+
+            # Populate initial data using custom field default values
+            for field in fields:
+                if field.name not in self.initial_data['custom_fields'] and field.default:
+                    if field.type == CF_TYPE_SELECT:
+                        field_value = field.choices.get(value=field.default).pk
+                    elif field.type == CF_TYPE_BOOLEAN:
+                        field_value = bool(field.default)
+                    else:
+                        field_value = field.default
+                    self.initial_data['custom_fields'][field.name] = field_value
+
     def _save_custom_fields(self, instance, custom_fields):
         content_type = ContentType.objects.get_for_model(self.Meta.model)
         for field_name, value in custom_fields.items():

netbox/extras/tests/test_customfields.py

@@ -301,6 +301,40 @@ class CustomFieldAPITest(APITestCase):
         cfv = self.site.custom_field_values.get(field=self.cf_select)
         self.assertEqual(cfv.value.pk, data['custom_fields']['magic_choice'])
 
+    def test_set_custom_field_defaults(self):
+        """
+        Create a new object with no custom field data. Custom field values should be created using the custom fields'
+        default values.
+        """
+        CUSTOM_FIELD_DEFAULTS = {
+            'magic_word': 'foobar',
+            'magic_number': '123',
+            'is_magic': 'true',
+            'magic_date': '2019-12-13',
+            'magic_url': 'http://example.com/',
+            'magic_choice': self.cf_select_choice1.value,
+        }
+
+        # Update CustomFields to set default values
+        for field_name, default_value in CUSTOM_FIELD_DEFAULTS.items():
+            CustomField.objects.filter(name=field_name).update(default=default_value)
+
+        data = {
+            'name': 'Test Site X',
+            'slug': 'test-site-x',
+        }
+
+        url = reverse('dcim-api:site-list')
+        response = self.client.post(url, data, format='json', **self.header)
+
+        self.assertHttpStatus(response, status.HTTP_201_CREATED)
+        self.assertEqual(response.data['custom_fields']['magic_word'], CUSTOM_FIELD_DEFAULTS['magic_word'])
+        self.assertEqual(response.data['custom_fields']['magic_number'], str(CUSTOM_FIELD_DEFAULTS['magic_number']))
+        self.assertEqual(response.data['custom_fields']['is_magic'], bool(CUSTOM_FIELD_DEFAULTS['is_magic']))
+        self.assertEqual(response.data['custom_fields']['magic_date'], CUSTOM_FIELD_DEFAULTS['magic_date'])
+        self.assertEqual(response.data['custom_fields']['magic_url'], CUSTOM_FIELD_DEFAULTS['magic_url'])
+        self.assertEqual(response.data['custom_fields']['magic_choice'], self.cf_select_choice1.pk)
+
 
 class CustomFieldChoiceAPITest(APITestCase):
     def setUp(self):