Problem acknowledge merge with tx message

Hello Brocaar and everyone,

Is this a bug or a feature request?
Unexpected behavior
What did you expect?
Merge with the last Tx message on the queue and ACK message.
What happened?
I want to setup the time of my device just after receive a specific confirmed message. I develop a program in Go to publish on sending queue via MQTT.
MQTT transmission are probed and stored on local DB. For example:

 type | port |             time
 ACK  |      | 2018-03-27 11:26:29.619763+02
 TX   | 1    | 2018-03-27 11:26:29.598217+02
 RX   | 1    | 2018-03-27 11:26:29.585954+02
 TX   | 1    | 2018-03-27 11:16:26.222354+02
 RX   | 1    | 2018-03-27 11:16:26.212988+02
 ACK  |      | 2018-03-27 11:09:39.883642+02
 RX   | 3    | 2018-03-27 11:09:39.865575+02
 TX   | 1    | 2018-03-27 11:06:22.869106+02
 RX   | 1    | 2018-03-27 11:06:22.864663+02
 JOIN |      | 2018-03-27 11:06:09.875749+02

The message on port 1 is the setup message
The message on port 2 is unconfirmed message (so no ack expected)
But there are sometimes an ACK publish just after an unconfirmed message or my TX message or nothing …
And sometimes (but I think it isn’t totally due to this behave) my device don’t receive any acknoledge message and it tryed to join the network.

I want to know if when LoRa Server merge the TX and ACK at the last moment, or should I send my TX message few moment after ACK publish and wait the next RX message?

What version are your using?
loraserver 0.25.0 on linux amd64

Best Regards,
David Boyer

I’m not sure if I understand your issue and what ACK you mean. One ACK is exposed by the LoRa Gateway Bridge (to acknowledge that the gateway has scheduled the downlink), one by LoRa App Server. The latter one is published as a MQTT message by LoRa App Server when your device has the ACK bit set on an uplink message.

I assume he’s talking about the ACK published as a MQTT message as his program listens on MQTT topics