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hominidae asked

mqtt topics published (W/.../) only once are being repeatedly used/subscribed by Cerbo GX

During some tests with NR and mqtt, using the Broker on the Cerbo, I noticed a strange behaviour.

I can change dbus values just fine, by publishing them via the W/.../ topic over mqtt.

After a publish, the Cerbo accepts the value and re-publishes it via the N/.../ topc tree just fine.

However, after the Cerbo excepted the new value, the W/.../topic does not get deleted from the Broker, although the retain flag has been set to false during publish.

Following this, one can see that same value re-appears after some time without a re-publish had been taken place (tested by the value had been manually changed to a different value via the GX menu beforehand and NR flow had meanwhile been stopped - so no external commands/manual interaction with mqtt broker on the Cerbo).

As far as I can tell, it is reproducable and "re-publish" takes paces, some time after midnight, when a new day started.

I actually consider this a bug in the Cerbo/Venus OS implementation, don't you think?

It normally is good practice that, after a topic without retain flag has been published, it gets deleted by the sole subscriber, to mimick a get/set remote control scheme, like with N/.../ and W/.../ topics on dbus.

...or am I missing something here?

cerbo gxNode-REDMQTT
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