MQTT - remove auto-keep-alive configuration parameter

[dometec]

Hi,

this option is useful when the user can explicitly call the Vert.x MQTT MqttClient.ping() method
(see: https://github.com/vert-x3/vertx-mqtt/blob/cc90db35b19a9b378100dcaf09acb4afd5001426/src/main/java/io/vertx/mqtt/MqttClient.java#L260
),
allowing the application to disable the automatic keep-alive and implement a custom keep-alive mechanism.

However, when using smallrye-reactive-messaging, the underlying MqttClient is not directly accessible, so it is not possible to call ping() manually. As a result, the keep-alive mechanism cannot actually be disabled or customized, even though the configuration option exists.

For this reason, I believe the auto keep-alive configuration parameter is ineffective in this context and should either be removed or clearly documented as unsupported (if I set the option to false, the connection is closed every keepalivesec*1.5).

[cescoffier]

MAkes sense, WDYT @ozangunalp ?

[ozangunalp]

I cannot think of a use case where we would allow disabling auto keep-alive and pings to be handled by the application.
@dometec is there a use case you can think of?

[dometec]

No, I tested the option simply out of curiosity.

[cescoffier]

Ok, then I agree we should remove it.

It should be considered as a "breaking change" (even if using that option before was misleading). @ozangunalp Don't forget to drop a line in the Quarkus release notes once released and integrated.