Security: validate outbound llm URLs and block internal endpoints

src/documents/tests/test_api_app_config.py

@@ -5,6 +5,7 @@ from unittest.mock import patch
 
 from django.contrib.auth.models import User
 from django.core.files.uploadedfile import SimpleUploadedFile
+from django.test import override_settings
 from rest_framework import status
 from rest_framework.test import APITestCase
 
@@ -693,3 +694,17 @@ class TestApiAppConfig(DirectoriesMixin, APITestCase):
                 content_type="application/json",
             )
             mock_update.assert_called_once()
+
+    @override_settings(LLM_ALLOW_INTERNAL_ENDPOINTS=False)
+    def test_update_llm_endpoint_blocks_internal_endpoint_when_disallowed(self) -> None:
+        response = self.client.patch(
+            f"{self.ENDPOINT}1/",
+            json.dumps(
+                {
+                    "llm_endpoint": "http://127.0.0.1:11434",
+                },
+            ),
+            content_type="application/json",
+        )
+        self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
+        self.assertIn("non-public address", str(response.data).lower())