wolf SSL / Mbed 2 deprecated HelloMQTTS

Simple usage example of MQTTS library

Dependencies:   EthernetInterface MQTTS NTPClient SDFileSystem mbed-rtos mbed wolfSSL

Fork of HelloMQTT by MQTT

MQTT is light weight protocol for M2M, IoT. MQTTS adds TLS(SSL) security layer into the MQTT. This program shows simple usage example of MQTTS library.

Connect information has to be stored in SD file "connectInfo.txt", with following lines in it.

  • Host Name
  • User Name
  • Password
  • Client ID
  • Topic

The program asks following information on the terminal

  • Port Number to be connected. If the port is >8000 it assumes MQTTS.
  • Message to be published
  • Certificate file name, if MQTTS. Input file name on SD card. Simply Return key force it to no server verification. The program set up the realtime clock by NTP for certificate verification.

This program was tested with FRDM-K64F, against Sango MQTT server by Shiguredo. https://sango.shiguredo.jp/

References:

main.cpp

Committer:
icraggs
Date:
2014-02-04
Revision:
0:0cae29831d01
Child:
1:a1d5c7a6acbc

File content as of revision 0:0cae29831d01:

#include "mbed.h"
#include "EthernetInterface.h"
#include "C12832_lcd.h"

#include "MQTTPacket.h"


DigitalOut myled(LED2);
C12832_LCD lcd;

int publish()
{
    MQTTPacket_connectData data = MQTTPacket_connectData_initializer;
    int rc = 0;
    char buf[200];
    int buflen = sizeof(buf);
    TCPSocketConnection mysock; 
    MQTTString topicString = MQTTString_initializer;
    char* payload = "I'm alive!";
    int payloadlen = strlen(payload);
    int len = 0;
    
    mysock.connect("m2m.eclipse.org", 1883);
          
    data.clientID.cstring = "mbed test client - Ian Craggs";
    data.keepAliveInterval = 20;
    data.cleansession = 1;
    data.MQTTVersion = 3;

    len = MQTTSerialize_connect(buf, buflen, &data);

    topicString.cstring = "mbed NXP LPC1768";
    len += MQTTSerialize_publish(buf + len, buflen - len, 0, 0, 0, 0, topicString, payload, payloadlen);

    len += MQTTSerialize_disconnect(buf + len, buflen - len);

    rc = 0;
    while (rc < len)
    {
        int rc1 = mysock.send(buf, len);
        if (rc1 == -1)
        {
            lcd.printf("Send failed\n");
            break;
        }
        else
            rc += rc1;
    }
    if (rc == len)
        lcd.printf("Send succeeded\n");
    wait(0.2);

    return 0;
}

int main() {
    EthernetInterface eth;
    eth.init(); //Use DHCP
    eth.connect();
    lcd.printf("IP Address is %s\n", eth.getIPAddress());
    
    while(1) {
        myled = 1;
        publish();
        wait(0.2);
        myled = 0;
        publish();
        wait(0.2);
    }
    
    eth.disconnect();
}