offline messages batching

[abdelhameedhamdy]

Hey, Greetings,

I have a subscriber with qos 1 and clean set to false, to fetch offline persisted messages from broker, while subscriber is offline.
I am wondering is there a way to process the received offline message as batches rather than one-by-one,

I think there is a inflight max messages count option in MQTT v5 protocol can be configured.

How could I enable this message batching technique using MQTT.js ?

Thanks

[robertsLando]

I'm not aware of nothing on mqtt protocol side to handle sending batch offline messages. You could try by checking mqtt 5 specs.

[abdelhameedhamdy]

Theres is some thing called inflight messages count in mqtt 5 spec, https://docs.oasis-open.org/mqtt/mqtt/v5.0/mqtt-v5.0.html

It states :
If both Client and Server set Receive Maximum to 1, they make sure that no more than one message is “in-flight” at any one time. In this case no QoS 1 message will be received after any later one even on re-connection. For example a subscriber might receive them in the order 1,2,3,3,4 but not 1,2,3,2,3,4. Refer to section 4.9 Flow Control for details of how the Receive Maximum is used.

[robertsLando]

Yeah but that I don't understand how you could use that to do what you are looking for. In order to do that you should implement some logic on broker side or on clients but I dunno how you implemented your MQTT application