Nucleus 2.10 upgraded to MQTT5 amongst other things. Prior to 2.10, calls to subscribe_to_iot_core would throw a awsiot.greengrasscoreipc.model.ServiceError exception if Greengrass was not connected to IoT Core. This was used as a rollback trigger in the case of not being able to subscribe when the component starts up after swapping to the new certificate.
When Nucleus 2.10 or later is used, the subscribe_to_iot_core call blocks until Greengrass eventually connects. The component needs a different way (not an exception from that call) to determine that the subscribe is not working.
Nucleus 2.10 upgraded to MQTT5 amongst other things. Prior to 2.10, calls to
subscribe_to_iot_corewould throw aawsiot.greengrasscoreipc.model.ServiceErrorexception if Greengrass was not connected to IoT Core. This was used as a rollback trigger in the case of not being able to subscribe when the component starts up after swapping to the new certificate.When Nucleus 2.10 or later is used, the
subscribe_to_iot_corecall blocks until Greengrass eventually connects. The component needs a different way (not an exception from that call) to determine that the subscribe is not working.