MQTT long messages guarantees

[daviherc]

Hello all,

I am receiving a long message (~550kb) through MQTT, so I get a great amount of message pieces along ~20s. I get all these messages from the MQTT_EVENT_DATA event type.

Starting from the second piece of the message, there is no mqtt topic in the event object.

So I was wondering: is it guaranteed that the pieces of the same message will be in sequence, and any other message that might come would be received after the transfer of all the pieces?

To make it super clear, if I have message A, with pieces (a1,a2,a3,a4,a5,a6,a7) and message B with one piece (B1). If I send first A then B, would I be guaranteed to get (a1,a2,a3,a4,a5,a6,a7,B1) or could it be possible to receive (a1,a2,a3,B1,a4,a5,a6,a7)?

[br10101]

Same question here