Now, we will check what happens when the MQTT client that controls the vehicle disconnects unexpectedly from the MQTT server and our vehicle remote control application disconnects unexpectedly, too. Pay attention to all the steps because we will manually interrupt the execution of both programs to understand a specific problem that we will solve by taking advantage of the last will and testament feature combined with the retained flag value.
You will have to be quick to run the next steps. Hence, make sure you read all the steps and then execute them.
Execute the following line to start the vehicle remote control example on any computer or device that you want to use as the MQTT client and uses Linux or macOS:
python3 vehicle_mqtt_remote_control.py
In Windows, you must execute the following line:
python vehicle_mqtt_remote_control...