[API] Bug fix for FilterableSerializerMixin (#10632)

- Handle case where data is being exported

src/backend/InvenTree/InvenTree/mixins.py

@@ -6,6 +6,7 @@ from rest_framework import generics, mixins, status
 from rest_framework.response import Response
 
 import data_exporter.mixins
+import data_exporter.serializers
 import importer.mixins
 from InvenTree.fields import InvenTreeNotesField, OutputConfiguration
 from InvenTree.helpers import (
@@ -231,7 +232,12 @@ class OutputOptionsMixin:
         serializer = super().get_serializer(*args, **kwargs)
 
         # Check if the serializer actually can be filtered - makes not much sense to use this mixin without that prerequisite
-        if not isinstance(serializer, FilterableSerializerMixin):
+        if isinstance(
+            serializer, data_exporter.serializers.DataExportOptionsSerializer
+        ):
+            # Skip in this instance, special case for determining export options
+            pass
+        elif not isinstance(serializer, FilterableSerializerMixin):
             raise Exception(
                 'INVE-I2: `OutputOptionsMixin` can only be used with serializers that contain the `FilterableSerializerMixin` mixin'
             )

src/backend/InvenTree/part/test_api.py

@@ -3339,3 +3339,27 @@ class PartTestTemplateTest(PartAPITestBase):
         response = self.patch(url, {'choices': 'a,b,c,d,e,f,f'}, expected_code=400)
 
         self.assertIn('Choices must be unique', str(response.data['choices']))
+
+
+class PartParameterTests(PartAPITestBase):
+    """Unit test for PartParameter API endpoints."""
+
+    def test_export_data(self):
+        """Test data export functionality for PartParameter objects."""
+        url = reverse('api-part-parameter-list')
+
+        response = self.options(
+            url,
+            data={
+                'export': True,
+                'export_plugin': 'inventree-exporter',
+                'part_detail': True,
+                'template_detail': True,
+            },
+            expected_code=200,
+        )
+
+        fields = response.data['actions']['GET'].keys()
+
+        self.assertIn('export_format', fields)
+        self.assertIn('export_plugin', fields)