Subscriber callback 'Message Received'

[tommasogiannoni]

How can i show message received by subscriber ?

I have 1 rpl-border-router and 2 mqtt-publisher-subscriber: main_core.c

When i start simulation i read message received by border router but i want that the subscriber mote show 'Message received..' read from specific topic every clock time.

I found this function:mqtt_sn_recv_parser But it never called. So how can i run callback function on subscriber and show message received from other mqtt-mote ?

Thanks

[aignacio]

Hi @tommasogiannoni FTF, without seeing any code it's hard to guess exactly what's going on, also I couldn't understand well your second sentence, can you clarify what you cannot do? If you mean to say: 1) I want to see what the nodes receives from some specific mqtt-sn topic, you just need to subscribe to the topic and publish on the broker as a normal MQTT req. 2) You want to print what's coming from some topic, the built-in functions implemented does that like a charm Ps.: You DON'T run the cb function, callback stands for automatically triggered function that'll be called by the OS in the appropriate time.

[aignacio]

btw, r u following this? :)

[tommasogiannoni]

Hi @aignacio, thanks for reply. my question is about the mqtt_sn_callback(char *topic, char *message) function:

void mqtt_sn_callback(char *topic, char *message) { printf("\nMessage received:"); printf("\nTopic:%s Message:%s",topic,message); }

My Mote publisher-subscriber do this:

mqtt_sn_init(); mqtt_sn_create_sck(mqtt_sn_connection, all_topics, ss(all_topics), mqtt_sn_callback); mqtt_sn_sub('/topic_1',0);

and in the process main function, in a while(1) loop:

mqtt_sn_pub("/topic_1", msg_to_snd, true, 0);

where msg_to_snd is a simple string like "MSG[NODE ID: %d]"

So the second Mote that is only a subscriber: mqtt_sn_init(); mqtt_sn_sub('/topic_1', 0);

and do nothing in the process main function. there is also a border-router rpl mote, that print 'msg_to_snd'every time.

So the function mqtt_sn_callback(char *topic, char *message) is NEVER called. I followed your guide, by starting rpl by doing this: sudo ./tunslip6 -a 127.0.0.1 aaaa::1/64 and start mqtt by doing this: sudo ./broker_mqtts config.mqtt

where do I have to change to have the subscriber mote, subscribed to that topic ('/topic_1') automatically run callback function?

Thanks to for the help

[aignacio]

R u sure that the first mote is publishing the messages in the brokers? Pls attached the log of the mqtt-sn broker to see if everything goes well in the pub side.

[tommasogiannoni]

This is the Log:

https://ibb.co/GQY2VxK https://ibb.co/Sm3N20V

3 Mote: Mote 1 is the rpl-border.router Mote 2 is the publisher main_core.c Mote 3 is the subscriber.

The rpl-border router print message that was sent by mote 2, but the mote 3 don't run callback never.

[aignacio]

@tommasogiannoni can you provide the BROKER log as well? I wanna check if the publisher is pub. properly as it meant to be

[tommasogiannoni]

@aignacio How can i log the broker? You mean the rpl-border-router ?

Thanks for help !

[tommasogiannoni]

This is what the command sudo ./broker_mqtts config.mqtt log to terminal during simulation: https://ibb.co/DVD5DX4

[aignacio]

Hi @tommasogiannoni can you confirm if the device_id is different for the two motes? I'm asking this cause in your log seems to have a dupplicate attempt connection. Also, in the fw of both motes r u registering all topics that you use in this structure? This needs to be done because in the MQTT-SN protocol, we don't use the full topic name, we use topic ids that must be previously registered and this is done in this line and this ones