Contiki os MQTT

Question

HI i try to connect my mqtt mote in my cooja simluator to my mosquitto server on my desktop. But it keep getting fail to connect and i was able to ping rpl router but not my mqtt client mote. i am using the example from https://github.com/esar/contiki-mqtt.

Could anyone please advise me on the mistake i made? Thank you

This are the code i used

#include "stdio.h"
#include "contiki.h"
#include "contiki-net.h"
#include "mqtt-service.h"
PROCESS(mqtt_publisher_process, "MQTT Publisher");
PROCESS_NAME(mqtt_process);
AUTOSTART_PROCESSES(&mqtt_process, &mqtt_publisher_process);

PROCESS_THREAD(mqtt_publisher_process, ev, data)
{

    static uip_ip6addr_t server_address;

    // printf("address %d\n",server_address);
    // Allocate buffer space for the MQTT client
    static uint8_t in_buffer[64];
    static uint8_t out_buffer[64];

    // Setup an mqtt_connect_info_t structure to describe
    // how the connection should behave
    static mqtt_connect_info_t connect_info =
    {
        .client_id = "contiki",
        .username = "user",
        .password = "user",
        .will_topic = "dev/text",
        .will_message = NULL,
        .keepalive = 60,
        .will_qos = 0,
        .will_retain = 0,
        .clean_session = 1
    };

    // The list of topics that we want to subscribe to
    static const char* topics[] =
    {
      "0", "1", "2", "3", "4", "5", NULL
    };
     PROCESS_BEGIN();
        // Set the server address
    uip_ip6addr(&server_address,0,0,0,0,0,0,0,1);

    // Initialise the MQTT client
    mqtt_init(in_buffer, sizeof(in_buffer),
              out_buffer, sizeof(out_buffer));

    // Ask the client to connect to the server
    // and wait for it to complete.
    mqtt_connect(&server_address, UIP_HTONS(33065),1, &connect_info);
    // mqtt_connect(&server_address, 1883,1, &connect_info);
    PROCESS_WAIT_EVENT_UNTIL(ev == mqtt_event);
    if(mqtt_connected())
    {
        static int i;

        for(i = 0; topics[i] != NULL; ++i)
        {
            // Ask the client to subscribe to the topic
            // and wait for it to complete
            mqtt_subscribe(topics[i]);
            PROCESS_WAIT_EVENT_UNTIL(ev == mqtt_event);
        }

        // Loop waiting for events from the MQTT client
        while(1)
        {
            PROCESS_WAIT_EVENT_UNTIL(ev == mqtt_event);

            // If we've received a publish event then print
            // out the topic and message
            if(mqtt_event_is_publish(data))
            {
                const char* topic = mqtt_event_get_topic(data);
                const char* message = mqtt_event_get_data(data);
                int level = 0;

                printf("%s = %s\n", topic, message);

                // Relay the received message to a new topic
                mqtt_publish("new_topic", message, 0, 1);
            }else{

            }
        }
    } else
        printf("mqtt service connect failed\n");
     PROCESS_END();
}

kartben kartben · Accepted Answer · 2017-01-13T08:14:20

I doubt that the MQTT server, which you say runs on your desktop, has IPv6 address ::1, right?

Rather than:

uip_ip6addr(&server_address,0,0,0,0,0,0,0,1);

you probably want to put the address of your desktop computer that runs Mosquitto?

Contiki os MQTT

1 Answers