Fix: report no unapplied migrations when the applied migrations cannot be read

src/documents/tests/test_api_status.py

@@ -564,3 +564,25 @@ class TestSystemStatus(APITestCase):
             database["migration_status"],
             {"latest_migration": None, "unapplied_migrations": []},
         )
+
+    def test_system_status_migration_query_error(self) -> None:
+        """
+        GIVEN:
+            - The migration graph loads but reading the applied migrations fails
+        WHEN:
+            - The system status is requested
+        THEN:
+            - No migrations are reported as unapplied, since the state is unknown
+        """
+        self.client.force_login(self.user)
+        with mock.patch("documents.views.MigrationRecorder") as recorder:
+            recorder.Migration.objects.all.side_effect = Exception("query failed")
+            response = self.client.get(self.ENDPOINT)
+
+        self.assertEqual(response.status_code, status.HTTP_200_OK)
+        database = response.data["database"]
+        self.assertEqual(database["status"], "ERROR")
+        self.assertEqual(
+            database["migration_status"],
+            {"latest_migration": None, "unapplied_migrations": []},
+        )

src/documents/views.py

@@ -5357,6 +5357,7 @@ class SystemStatusView(PassUserMixin):
                 for m in MigrationRecorder.Migration.objects.all().order_by("id")
             ]
         except Exception as e:
+            all_migrations = []
             applied_migrations = []
             db_status = "ERROR"
             logger.exception(