[change] Add output on Command timeout exceeded

Author: Alexandre Vincent

openwisp_controller/connection/connectors/ssh.py

@@ -198,13 +198,17 @@ def exec_command(
             logger.exception(e)
             raise e
         # store command exit status
+        exit_status = None
         # workaround https://github.com/paramiko/paramiko/issues/1815
         # workaround https://github.com/paramiko/paramiko/issues/1787
         # Ref. https://docs.paramiko.org/en/stable/api/channel.html#paramiko.channel.Channel.recv_exit_status  # noqa
-        stdout.channel.status_event.wait(
+        if not stdout.channel.status_event.wait(
             timeout=timeout - int(time.perf_counter() - start_cmd)
-        )
-        assert stdout.channel.status_event.is_set()
+        ):
+            output = "Command timeout exceeded."
+            logger.info(output)
+            return output, -1
+
         exit_status = stdout.channel.exit_status
         # log standard output
         # try to decode to UTF-8, ignoring unconvertible characters

openwisp_controller/connection/tests/test_ssh.py

@@ -70,6 +70,19 @@ def test_connection_failed_command(self, mocked_debug, mocked_info):
             ]
         )
 
+    @mock.patch.object(ssh_logger, "info")
+    @mock.patch.object(ssh_logger, "debug")
+    def test_connection_command_timeout(self, mocked_debug, mocked_info):
+        ckey = self._create_credentials_with_key(port=self.ssh_server.port)
+        dc = self._create_device_connection(credentials=ckey)
+        dc.connector_instance.connect()
+        dc.connector_instance.exec_command("sleep 1", timeout=0)
+        mocked_info.assert_has_calls(
+            [
+                mock.call("Command timeout exceeded."),
+            ]
+        )
+
     @mock.patch.object(ssh_logger, "info")
     @mock.patch.object(ssh_logger, "debug")
     def test_connection_failed_command_suppressed_output(