CODEWITHSUNDEEP
network-programmingmosquittocoojacontiki-ng
idrr_97
idrr_97

Reputation: 1

I'm running Contiki-ng container on ipv6 network docker. My mqtt mote code is not able to send messages to topics in mosquitto broker

My setup :

  1. Ubuntu22.04 VM running IPv6 network enabled docker - 2001:db8:2::/64

  2. Contiki-ng container on the docker with ifconfig -

eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 172.18.0.2  netmask 255.255.0.0  broadcast 172.18.255.255
        inet6 fe80::42:acff:fe12:2  prefixlen 64  scopeid 0x20<link>
        inet6 2001:db8:2::2  prefixlen 64  scopeid 0x0<global>
        ether 02:42:ac:12:00:02  txqueuelen 0  (Ethernet)
        RX packets 208  bytes 182016 (182.0 KB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 95  bytes 7465 (7.4 KB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

lo: flags=73<UP,LOOPBACK,RUNNING>  mtu 65536
        inet 127.0.0.1  netmask 255.0.0.0
        inet6 ::1  prefixlen 128  scopeid 0x10<host>
        loop  txqueuelen 1000  (Local Loopback)
        RX packets 370  bytes 33910 (33.9 KB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 370  bytes 33910 (33.9 KB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0
  1. Mosquitto.conf settings -
pid_file /run/mosquitto/mosquitto.pid

persistence true
persistence_location /var/lib/mosquitto/

log_dest file /var/log/mosquitto/mosquitto.log

include_dir /etc/mosquitto/conf.d

listener 1883
allow_anonymous true

  1. command to run mqttbroker - mosquitto -c /etc/mosquitto/mosquitto.conf -v

  2. my cooja mote codes for node A, B, C -

    Basically what I'm trying to achieve is a cyclic connection between 3 nodes where Node A publishes to Node B and subscribes to Node C via topics. The same is the case with Node B and Node C.

Node A Code is below :


#include "contiki.h"
#include "os/net/app-layer/mqtt/mqtt.h"
#include <string.h>

#define BROKER_IP "2001:db8:2::2"
#define PUBLISH_TOPIC "A2B"  // Node A publishes to "A2B"
#define SUBSCRIBE_TOPIC "C2A"  // Node A subscribes to "C2A"
#define CLIENT_ID "node-a"  // Unique client ID for Node A
#define MQTT_PORT 1883
#define PUBLISH_INTERVAL (CLOCK_SECOND * 10) // Adjust the interval as needed
#define MQTT_MESSAGE_BUFFER_SIZE 128  // Defines the buffer size for MQTT messages

static struct mqtt_connection conn;
static char broker_ip[] = BROKER_IP;
static char client_id[] = CLIENT_ID;

PROCESS(node_a_process, "Node A Process");
AUTOSTART_PROCESSES(&node_a_process);

static void mqtt_event(struct mqtt_connection *m, mqtt_event_t event, void *data) {
    switch (event) {
        case MQTT_EVENT_CONNECTED: {
            printf("Connected to the MQTT broker.\n");
            // Subscribe to "C2A" upon successful connection
            mqtt_subscribe(m, NULL, SUBSCRIBE_TOPIC, MQTT_QOS_LEVEL_1);
            break;
        }
        case MQTT_EVENT_DISCONNECTED: {
            printf("Disconnected from the MQTT broker.\n");
            break;
        }
        case MQTT_EVENT_PUBLISH: {
            // This is where Node A would handle incoming messages from "C2A"
            printf("Received a message on A.\n");
            break;
        }
        case MQTT_EVENT_SUBACK: {
            printf("Subscription successful.\n");
            break;
        }
        default:
            printf("Unhandled MQTT event: %d\n", event);
            break;
    }
}

PROCESS_THREAD(node_a_process, ev, data) {
    static struct etimer publish_timer;

    PROCESS_BEGIN();

    mqtt_status_t status = mqtt_register(&conn, &node_a_process, client_id, mqtt_event, MQTT_MESSAGE_BUFFER_SIZE);
    if(status != MQTT_STATUS_OK) {
        printf("MQTT register failed: %d\n", status);
        PROCESS_EXIT();
    }

    status = mqtt_connect(&conn, broker_ip, MQTT_PORT, 60, 1 /* Clean Session */);
    if(status != MQTT_STATUS_OK) {
        printf("MQTT connect failed: %d\n", status);
        PROCESS_EXIT();
    }

    etimer_set(&publish_timer, PUBLISH_INTERVAL);
    while(1) {
        PROCESS_WAIT_EVENT_UNTIL(etimer_expired(&publish_timer));
        etimer_reset(&publish_timer);

        // Node A publishes its message to "A2B"
        static char msg[] = "Message from A to B";
        status = mqtt_publish(&conn, NULL, PUBLISH_TOPIC, (uint8_t *)msg, strlen(msg), MQTT_QOS_LEVEL_1, MQTT_RETAIN_OFF);
        if(status != MQTT_STATUS_OK) {
            printf("MQTT publish failed: %d\n", status);
        }
    }

    PROCESS_END();
}

Node B Code is below :

#include "contiki.h"
#include "os/net/app-layer/mqtt/mqtt.h"
#include <string.h>

#define BROKER_IP "2001:db8:2::2"
#define PUBLISH_TOPIC "B2C"
#define SUBSCRIBE_TOPIC "A2B"
#define CLIENT_ID "node-b"
#define MQTT_PORT 1883
#define PUBLISH_INTERVAL (CLOCK_SECOND * 12) // Slightly offset from Node A for demonstration
#define MQTT_MESSAGE_BUFFER_SIZE 128  // This line defines the buffer size

static struct mqtt_connection conn;
static char broker_ip[] = BROKER_IP;
static char client_id[] = CLIENT_ID;

PROCESS(node_b_process, "Node B Process");
AUTOSTART_PROCESSES(&node_b_process);

static void mqtt_event(struct mqtt_connection *m, mqtt_event_t event, void *data) {
    switch (event) {
        case MQTT_EVENT_CONNECTED: {
            printf("Connected to the MQTT broker.\n");
            mqtt_subscribe(m, NULL, SUBSCRIBE_TOPIC, MQTT_QOS_LEVEL_1);
            break;
        }
        case MQTT_EVENT_DISCONNECTED: {
            printf("Disconnected from the MQTT broker.\n");
            break;
        }
        case MQTT_EVENT_PUBLISH: {
            printf("Received a message on B.\n");
            // Node B could process the message here before sending to C
            break;
        }
        case MQTT_EVENT_SUBACK: {
            printf("Subscription successful.\n");
            break;
        }
        default:
            printf("Unhandled MQTT event: %d\n", event);
            break;
    }
}

PROCESS_THREAD(node_b_process, ev, data) {
    static struct etimer publish_timer;

    PROCESS_BEGIN();

    mqtt_status_t status = mqtt_register(&conn, &node_b_process, client_id, mqtt_event, MQTT_MESSAGE_BUFFER_SIZE);
    if(status != MQTT_STATUS_OK) {
        printf("MQTT register failed: %d\n", status);
        PROCESS_EXIT();
    }
    
    status = mqtt_connect(&conn, broker_ip, MQTT_PORT, 60, 1 /* Clean Session */);
    if(status != MQTT_STATUS_OK) {
        printf("MQTT connect failed: %d\n", status);
        PROCESS_EXIT();
    }

    etimer_set(&publish_timer, PUBLISH_INTERVAL);
    while(1) {
        PROCESS_WAIT_EVENT_UNTIL(etimer_expired(&publish_timer));
        etimer_reset(&publish_timer);

        static char msg[] = "Message from B to C";
        status = mqtt_publish(&conn, NULL, PUBLISH_TOPIC, (uint8_t *)msg, strlen(msg), MQTT_QOS_LEVEL_1, MQTT_RETAIN_OFF);
        if(status != MQTT_STATUS_OK) {
            printf("MQTT publish failed: %d\n", status);
        }
    }

    PROCESS_END();
}

Node C code is below :

#include "contiki.h"
#include "os/net/app-layer/mqtt/mqtt.h"
#include <string.h>

#define BROKER_IP "2001:db8:2::2"
#define PUBLISH_TOPIC "C2A"
#define SUBSCRIBE_TOPIC "B2C"
#define CLIENT_ID "node-c"
#define MQTT_PORT 1883
#define PUBLISH_INTERVAL (CLOCK_SECOND * 14) // Slightly offset from Node B for demonstration
#define MQTT_MESSAGE_BUFFER_SIZE 128  // This line defines the buffer size

static struct mqtt_connection conn;
static char broker_ip[] = BROKER_IP;
static char client_id[] = CLIENT_ID;

PROCESS(node_c_process, "Node C Process");
AUTOSTART_PROCESSES(&node_c_process);

static void mqtt_event(struct mqtt_connection *m, mqtt_event_t event, void *data) {
    switch (event) {
        case MQTT_EVENT_CONNECTED: {
            printf("Connected to the MQTT broker.\n");
            mqtt_subscribe(m, NULL, SUBSCRIBE_TOPIC, MQTT_QOS_LEVEL_1);
            break;
        }
        case MQTT_EVENT_DISCONNECTED: {
            printf("Disconnected from the MQTT broker.\n");
            break;
        }
        case MQTT_EVENT_PUBLISH: {
            printf("Received a message on C.\n");
            // Node C could process the message here before sending to A
            break;
        }
        case MQTT_EVENT_SUBACK: {
            printf("Subscription successful.\n");
            break;
        }
        default:
            printf("Unhandled MQTT event: %d\n", event);
            break;
    }
}

PROCESS_THREAD(node_c_process, ev, data) {
    static struct etimer publish_timer;

    PROCESS_BEGIN();

    mqtt_status_t status = mqtt_register(&conn, &node_c_process, client_id, mqtt_event, MQTT_MESSAGE_BUFFER_SIZE);
    if(status != MQTT_STATUS_OK) {
        printf("MQTT register failed: %d\n", status);
        PROCESS_EXIT();
    }
    
    status = mqtt_connect(&conn, broker_ip, MQTT_PORT, 60, 1 /* Clean Session */);
    if(status != MQTT_STATUS_OK) {
        printf("MQTT connect failed: %d\n", status);
        PROCESS_EXIT();
    }

    etimer_set(&publish_timer, PUBLISH_INTERVAL);
    while(1) {
        PROCESS_WAIT_EVENT_UNTIL(etimer_expired(&publish_timer));
        etimer_reset(&publish_timer);

        static char msg[] = "Message from C to A";
        status = mqtt_publish(&conn, NULL, PUBLISH_TOPIC, (uint8_t *)msg, strlen(msg), MQTT_QOS_LEVEL_1, MQTT_RETAIN_OFF);
        if(status != MQTT_STATUS_OK) {
            printf("MQTT publish failed: %d\n", status);
        }
    }

    PROCESS_END();
}
  1. So I don't have any compilation errors but i'm only getting this output in mote output window :
00:10.382   ID:1    MQTT publish failed: 129
00:12.236   ID:2    MQTT publish failed: 129
00:14.899   ID:3    MQTT publish failed: 129
00:20.382   ID:1    MQTT publish failed: 129
00:24.236   ID:2    MQTT publish failed: 129
00:28.899   ID:3    MQTT publish failed: 129
00:30.382   ID:1    MQTT publish failed: 129
00:36.236   ID:2    MQTT publish failed: 129
00:40.382   ID:1    MQTT publish failed: 129
00:42.899   ID:3    MQTT publish failed: 129
00:48.236   ID:2    MQTT publish failed: 129
00:50.236   ID:2    Disconnected from the MQTT broker.
00:50.382   ID:1    Disconnected from the MQTT broker.
00:50.382   ID:1    MQTT publish failed: 129
00:50.899   ID:3    Disconnected from the MQTT broker.
00:56.899   ID:3    MQTT publish failed: 129
01:00.236   ID:2    MQTT publish failed: 129
01:00.382   ID:1    MQTT publish failed: 129
01:10.382   ID:1    MQTT publish failed: 129
01:10.899   ID:3    MQTT publish failed: 129

I couldn't solve the networking behind it so require help from both communities. The logs of mqtt broker also doesn't reflect any topics connection activity but when i try from terminal with mosquitto_pub and mosquitto_sub, i'm able to create topics and connect with broker.

Need to solve this? Please help.

Upvotes: 0

Views: 67

Answers (0)

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