[fix] Handled device not existing case in update_config task #205

Related to #205

Author: nemesifier

openwisp_controller/connection/tasks.py

@@ -19,12 +19,12 @@ def update_config(device_id):
     # (there may be multiple ones happening at the same time)
     time.sleep(2)
     # avoid repeating the operation multiple times
-    device = Device.objects.select_related('config').get(pk=device_id)
     try:
+        device = Device.objects.select_related('config').get(pk=device_id)
         if device.config.status == 'applied':
             return
-    except ObjectDoesNotExist:
-        logger.warning(f'Config with device id: {device_id} does not exist')
+    except ObjectDoesNotExist as e:
+        logger.warning(f'update_config("{device_id}") failed: {e}')
         return
     qs = device.deviceconnection_set.filter(device_id=device_id, enabled=True)
     conn = qs.first()

openwisp_controller/connection/tests/test_models.py

@@ -1,4 +1,5 @@
 import socket
+import uuid
 from unittest import mock
 
 import paramiko
@@ -354,12 +355,22 @@ def test_device_connection_set_connector(self):
 
     @mock.patch('logging.Logger.warning')
     @mock.patch('time.sleep')
-    def test_update_config_task_resilient_to_failure(
-        self, mocked_sleep, mocked_warning
-    ):
+    def test_update_config_missing_config(self, mocked_sleep, mocked_warning):
         pk = self._create_device().pk
         update_config.delay(pk)
-        mocked_warning.assert_called_with(f'Config with device id: {pk} does not exist')
+        mocked_warning.assert_called_with(
+            f'update_config("{pk}") failed: Device has no config.'
+        )
+        mocked_sleep.assert_called_once()
+
+    @mock.patch('logging.Logger.warning')
+    @mock.patch('time.sleep')
+    def test_update_config_missing_device(self, mocked_sleep, mocked_warning):
+        pk = uuid.uuid4()
+        update_config.delay(pk)
+        mocked_warning.assert_called_with(
+            f'update_config("{pk}") failed: Device matching query does not exist.'
+        )
         mocked_sleep.assert_called_once()