![](/media/cache/profiles/0230db486bc9cdd3583fee20469c7b2f.jpg.50x50_q85.jpg)
Simple usage example of MQTTS library
Dependencies: EthernetInterface MQTTS NTPClient SDFileSystem mbed-rtos mbed wolfSSL
Fork of HelloMQTT by
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:
- wolfSSL Home: https://www.wolfssl.com
- Original work of MQTT: https://developer.mbed.org/teams/mqtt.
- 日本語ホーム:https://developer.mbed.org/users/wolfSSL/code/HelloMQTTS/wiki/MQTTSホーム
Diff: main.cpp
- Revision:
- 2:638c854c0695
- Parent:
- 1:a1d5c7a6acbc
- Child:
- 3:7a6a899de7cc
--- a/main.cpp Wed Feb 05 10:50:15 2014 +0000 +++ b/main.cpp Wed Apr 30 13:16:09 2014 +0000 @@ -13,77 +13,198 @@ * Contributors: * Ian Craggs - initial API and implementation and/or initial documentation *******************************************************************************/ + + /** + This is a sample program to illustrate the use of the MQTT Client library + on the mbed platform. The Client class requires two classes which mediate + access to system interfaces for networking and timing. As long as these two + classes provide the required public programming interfaces, it does not matter + what facilities they use underneath. In this program, they use the mbed + system libraries. + + */ #include "mbed.h" #include "EthernetInterface.h" + #include "C12832_lcd.h" - -#include "MQTTPacket.h" - -DigitalOut myled(LED2); C12832_LCD lcd; -int publish() +#include "FP.cpp" +#include "MQTTClient.h" + + + +class IPStack { - MQTTPacket_connectData data = MQTTPacket_connectData_initializer; - int rc = 0; - char buf[200]; - int buflen = sizeof(buf); +public: + IPStack() + { + eth.init(); // Use DHCP + eth.connect(); + mysock.set_blocking(false, 1000); // 1 second Timeout + } + + int connect(char* hostname, int port) + { + return mysock.connect(hostname, port); + } + + int read(char* buffer, int len, int timeout) + { + mysock.set_blocking(false, timeout); + return mysock.receive(buffer, len); + } + + int write(char* buffer, int len, int timeout) + { + mysock.set_blocking(false, timeout); + return mysock.send(buffer, len); + } + + int disconnect() + { + return mysock.close(); + } + +private: + + EthernetInterface eth; TCPSocketConnection mysock; - MQTTString topicString = MQTTString_initializer; - char* payload = "I'm alive!"; - int payloadlen = strlen(payload); - int len = 0; + +}; + + +class Countdown +{ +public: + Countdown() + { + t = Timer(); + } + + Countdown(int ms) + { + t = Timer(); + countdown_ms(ms); + } + - 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); + bool expired() + { + return t.read_ms() >= interval_end_ms; + } + + void countdown_ms(int ms) + { + t.stop(); + interval_end_ms = ms; + t.reset(); + t.start(); + } + + void countdown(int seconds) + { + countdown_ms(seconds * 1000); + } + + int left_ms() + { + return interval_end_ms - t.read_ms(); + } + +private: + Timer t; + int interval_end_ms; +}; - topicString.cstring = "mbed NXP LPC1768"; - len += MQTTSerialize_publish(buf + len, buflen - len, 0, 0, 0, 0, topicString, payload, payloadlen); +int arrivedcount = 0; + +void messageArrived(MQTT::Message* message) +{ + lcd.printf("Message arrived: qos %d, retained %d, dup %d, packetid %d\n", message->qos, message->retained, message->dup, message->id); + lcd.printf("Payload %.*s\n", message->payloadlen, (char*)message->payload); + ++arrivedcount; +} - len += MQTTSerialize_disconnect(buf + len, buflen - len); +int connect(MQTT::Client<IPStack, Countdown>::connectionLostInfo* info) +{ + char* hostname = "m2m.eclipse.org"; + int port = 1883; + lcd.printf("Connecting to %s:%d\n", hostname, port); + int rc = info->network->connect(hostname, port); + lcd.printf("rc from TCP connect is %d\n", rc); + + MQTTPacket_connectData data = MQTTPacket_connectData_initializer; + data.MQTTVersion = 3; + data.clientID.cstring = "mbed-icraggs"; + rc = info->client->connect(&data); + lcd.printf("rc from MQTT connect is %d\n", rc); + + return rc; +} + + +int main(int argc, char* argv[]) +{ + IPStack ipstack = IPStack(); + float version = 0.3; + char* topic = "mbed-sample"; + + lcd.printf("Version is %f\n", version); + + MQTT::Client<IPStack, Countdown>client = MQTT::Client<IPStack, Countdown>(&ipstack); - 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); + MQTT::Client<IPStack, Countdown>::connectionLostInfo info = {&client, &ipstack}; + int rc = connect(&info); + + client.setConnectionLostHandler(connect); + + rc = client.subscribe(topic, MQTT::QOS1, messageArrived); + if (rc != 0) + lcd.printf("rc from MQTT subscribe is %d\n", rc); + + MQTT::Message message; + // QoS 0 + char buf[100]; + sprintf(buf, "Hello World! QoS 0 message from app version %f\n", version); + message.qos = MQTT::QOS0; + message.retained = false; + message.dup = false; + message.payload = (void*)buf; + message.payloadlen = strlen(buf)+1; + rc = client.publish(topic, &message); + while (arrivedcount == 0) + client.yield(100); + + // QoS 1 + sprintf(buf, "Hello World! QoS 1 message from app version %f\n", version); + message.qos = MQTT::QOS1; + message.payloadlen = strlen(buf)+1; + rc = client.publish(topic, &message); + while (arrivedcount == 1) + client.yield(100); + + // QoS 2 + sprintf(buf, "Hello World! QoS 2 message from app version %f\n", version); + message.qos = MQTT::QOS2; + message.payloadlen = strlen(buf)+1; + rc = client.publish(topic, &message); + while (arrivedcount == 2) + client.yield(100); + + rc = client.unsubscribe(topic); + if (rc != 0) + lcd.printf("rc from unsubscribe was %d\n", rc); + + rc = client.disconnect(); + if (rc != 0) + lcd.printf("rc from disconnect was %d\n", rc); + + ipstack.disconnect(); + + lcd.printf("Finishing with %d messages received\n", arrivedcount); + 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(); -}