docs: howto use Disconnect in presence of connection issues?

[andig]

I'm working with an MQTT broker that allows only a single connection per user at a time. Currently, connecting is implemented like this:

timeout := 30 * time.Second
if t := paho.Connect(); !t.WaitTimeout(timeout) {
	return errors.New("connect timeout")
} else if err := t.Error(); err != nil {
	return fmt.Errorf("connect: %w", err)
}
defer paho.Disconnect(1000)

From the docs, it's not clear, if a Disconnect is also required in case of the connection timeout in order to clean up any dangling go routines? I wouldn't expect it to be required in case of error.

[MattBrittan]

If t.Error() returns an error then you do not need to do anything further (unless the connection was already up). There is no need to call Disconnect, but there should be no harm in doing so. Note that if options.SetConnectRetry(true) has been called then Connect will keep trying to connect (and not return until the connection is up).

[andig]

Thank you @MattBrittan I'd expect the same for the error case. What would you expect in case of timeout (WaitTimeout(timeout) false with no error set)?

[MattBrittan]

What would you expect in case of timeout (WaitTimeout(timeout) false with no error set)?

Indeterminate, the connection process is still running so may succeed or fail. Call Disconnect to ensure it's stopped.