Processor time continues to be used after a failing connect command

[ghost]

I'm trying to write a small script that isn't guaranteed to have internet access on startup and can sometimes lose internet unexpectedly.

When there is no internet, the socket will fail to connect (as expected) due to name resolution not being available. A socket error is raised.
If connect is called again, the error will be raised again, but the processor utilization will increase.
This will continue to occur until the operating system denies you the ability to create threads.

e.x.

while True:
    try:
        mqttclient.connect()
        break
    except:
        sleep(10)
        continue

Things I've tried:

• Calling disconnect after a failed connect
• Only calling connect once. Once internet is established, publish never works
• Deleting mqttclient and re-creating it

Connect will have to be called again, since socket lifetimes are limited to 24 hours.
Related: #39 #124

[liuszeng]

Hi @zerasmus ,

We are aware of the issues you mentioned. Fixes are already merged in our internal dev branch and is pending to be released. Please stay tuned for future releases.

Thanks,
Liusu

[ghost]

FYI, I believe I've found the issue and a work-around:

aws-iot-device-sdk-python/AWSIoTPythonSDK/core/protocol/mqtt_core.py

Lines 189 to 200 in 47363e9

	def connect_async(self, keep_alive_sec, ack_callback=None):
	self._logger.info("Performing async connect...")
	self._logger.info("Keep-alive: %f sec" % keep_alive_sec)
	self._start_workers()
	self._load_callbacks()
	self._load_username_password()
	self._client_status.set_status(ClientStatus.CONNECT)
	rc = self._internal_async_client.connect(keep_alive_sec, ack_callback)
	if MQTT_ERR_SUCCESS != rc:
	self._logger.error("Connect error: %d", rc)
	raise connectError(rc)
	return FixedEventMids.CONNACK_MID

The workers are started and then the internal connect raises the exception without stoping the workers.
A workaround without modifying the library is to stop the workers using the internal variables:

while True:
    try:
        mqttclient.connect()
        break
    except Exception as e:
        # Stop the internal worker
        mqttclient._mqtt_core._event_consumer.stop()
        sleep(10)
        continue

[liuszeng]

Addressed in v1.4.0.