Simple mqtt client using the MqttPacket lib to create a connect to the public broker and publish series of message. Done over Ethernet.
Dependencies: C12832_lcd EthernetInterface MQTTPacket mbed-rtos mbed
main.cpp@0:96a5aefac643, 2018-06-13 (annotated)
- Committer:
- dvn
- Date:
- Wed Jun 13 19:51:38 2018 +0000
- Revision:
- 0:96a5aefac643
- Child:
- 1:d7773c5860c2
init mqtt message handling
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
dvn | 0:96a5aefac643 | 1 | #include "MQTTPacket.h" |
dvn | 0:96a5aefac643 | 2 | |
dvn | 0:96a5aefac643 | 3 | #include <errno.h> |
dvn | 0:96a5aefac643 | 4 | #include <stdlib.h> |
dvn | 0:96a5aefac643 | 5 | #include <string.h> |
dvn | 0:96a5aefac643 | 6 | |
dvn | 0:96a5aefac643 | 7 | #include "EthernetInterface.h" |
dvn | 0:96a5aefac643 | 8 | |
dvn | 0:96a5aefac643 | 9 | |
dvn | 0:96a5aefac643 | 10 | TCPSocketConnection mysock; |
dvn | 0:96a5aefac643 | 11 | |
dvn | 0:96a5aefac643 | 12 | int getdata(char* buf, int count) |
dvn | 0:96a5aefac643 | 13 | { |
dvn | 0:96a5aefac643 | 14 | return mysock.receive(buf, (size_t)count); |
dvn | 0:96a5aefac643 | 15 | } |
dvn | 0:96a5aefac643 | 16 | |
dvn | 0:96a5aefac643 | 17 | int toStop = 0; |
dvn | 0:96a5aefac643 | 18 | |
dvn | 0:96a5aefac643 | 19 | |
dvn | 0:96a5aefac643 | 20 | int main() |
dvn | 0:96a5aefac643 | 21 | { |
dvn | 0:96a5aefac643 | 22 | MQTTPacket_connectData data = MQTTPacket_connectData_initializer; |
dvn | 0:96a5aefac643 | 23 | int rc = 0; |
dvn | 0:96a5aefac643 | 24 | char buf[200]; |
dvn | 0:96a5aefac643 | 25 | int buflen = sizeof(buf); |
dvn | 0:96a5aefac643 | 26 | int msgid = 1; |
dvn | 0:96a5aefac643 | 27 | MQTTString topicString = MQTTString_initializer; |
dvn | 0:96a5aefac643 | 28 | int req_qos = 0; |
dvn | 0:96a5aefac643 | 29 | char* payload = "mypayload"; |
dvn | 0:96a5aefac643 | 30 | int payloadlen = strlen(payload); |
dvn | 0:96a5aefac643 | 31 | int len = 0; |
dvn | 0:96a5aefac643 | 32 | EthernetInterface eth; |
dvn | 0:96a5aefac643 | 33 | |
dvn | 0:96a5aefac643 | 34 | eth.init(); //Use DHCP |
dvn | 0:96a5aefac643 | 35 | eth.connect(); |
dvn | 0:96a5aefac643 | 36 | |
dvn | 0:96a5aefac643 | 37 | rc = mysock.connect("m2m.eclipse.org", 1883); |
dvn | 0:96a5aefac643 | 38 | |
dvn | 0:96a5aefac643 | 39 | data.clientID.cstring = "SendReceive mbed MQTT "; |
dvn | 0:96a5aefac643 | 40 | data.keepAliveInterval = 20; |
dvn | 0:96a5aefac643 | 41 | data.cleansession = 1; |
dvn | 0:96a5aefac643 | 42 | |
dvn | 0:96a5aefac643 | 43 | mysock.set_blocking(true, 1000); /* 1 second Timeout */ |
dvn | 0:96a5aefac643 | 44 | |
dvn | 0:96a5aefac643 | 45 | len = MQTTSerialize_connect(buf, buflen, &data); |
dvn | 0:96a5aefac643 | 46 | rc = mysock.send(buf, len); |
dvn | 0:96a5aefac643 | 47 | |
dvn | 0:96a5aefac643 | 48 | /* wait for connack */ |
dvn | 0:96a5aefac643 | 49 | if (MQTTPacket_read(buf, buflen, getdata) == CONNACK) |
dvn | 0:96a5aefac643 | 50 | { |
dvn | 0:96a5aefac643 | 51 | int connack_rc; |
dvn | 0:96a5aefac643 | 52 | |
dvn | 0:96a5aefac643 | 53 | if (MQTTDeserialize_connack(&connack_rc, buf, buflen) != 1 || connack_rc != 0) |
dvn | 0:96a5aefac643 | 54 | { |
dvn | 0:96a5aefac643 | 55 | printf("Unable to connect, return code %d\n", connack_rc); |
dvn | 0:96a5aefac643 | 56 | goto exit; |
dvn | 0:96a5aefac643 | 57 | } |
dvn | 0:96a5aefac643 | 58 | } |
dvn | 0:96a5aefac643 | 59 | else |
dvn | 0:96a5aefac643 | 60 | goto exit; |
dvn | 0:96a5aefac643 | 61 | |
dvn | 0:96a5aefac643 | 62 | /* subscribe */ |
dvn | 0:96a5aefac643 | 63 | topicString.cstring = "substopic"; |
dvn | 0:96a5aefac643 | 64 | len = MQTTSerialize_subscribe(buf, buflen, 0, msgid, 1, &topicString, &req_qos); |
dvn | 0:96a5aefac643 | 65 | |
dvn | 0:96a5aefac643 | 66 | rc = mysock.send(buf, len); |
dvn | 0:96a5aefac643 | 67 | if (MQTTPacket_read(buf, buflen, getdata) == SUBACK) /* wait for suback */ |
dvn | 0:96a5aefac643 | 68 | { |
dvn | 0:96a5aefac643 | 69 | int submsgid; |
dvn | 0:96a5aefac643 | 70 | int subcount; |
dvn | 0:96a5aefac643 | 71 | int granted_qos; |
dvn | 0:96a5aefac643 | 72 | |
dvn | 0:96a5aefac643 | 73 | rc = MQTTDeserialize_suback(&submsgid, 1, &subcount, &granted_qos, buf, buflen); |
dvn | 0:96a5aefac643 | 74 | if (granted_qos != 0) |
dvn | 0:96a5aefac643 | 75 | { |
dvn | 0:96a5aefac643 | 76 | printf("granted qos != 0, %d\n", granted_qos); |
dvn | 0:96a5aefac643 | 77 | goto exit; |
dvn | 0:96a5aefac643 | 78 | } |
dvn | 0:96a5aefac643 | 79 | } |
dvn | 0:96a5aefac643 | 80 | else |
dvn | 0:96a5aefac643 | 81 | goto exit; |
dvn | 0:96a5aefac643 | 82 | |
dvn | 0:96a5aefac643 | 83 | topicString.cstring = "pubtopic"; |
dvn | 0:96a5aefac643 | 84 | while (!toStop) |
dvn | 0:96a5aefac643 | 85 | { |
dvn | 0:96a5aefac643 | 86 | if (MQTTPacket_read(buf, buflen, getdata) == PUBLISH) |
dvn | 0:96a5aefac643 | 87 | { |
dvn | 0:96a5aefac643 | 88 | int dup; |
dvn | 0:96a5aefac643 | 89 | int qos; |
dvn | 0:96a5aefac643 | 90 | int retained; |
dvn | 0:96a5aefac643 | 91 | int msgid; |
dvn | 0:96a5aefac643 | 92 | int payloadlen_in; |
dvn | 0:96a5aefac643 | 93 | char* payload_in; |
dvn | 0:96a5aefac643 | 94 | int rc; |
dvn | 0:96a5aefac643 | 95 | MQTTString receivedTopic; |
dvn | 0:96a5aefac643 | 96 | |
dvn | 0:96a5aefac643 | 97 | rc = MQTTDeserialize_publish(&dup, &qos, &retained, &msgid, &receivedTopic, |
dvn | 0:96a5aefac643 | 98 | &payload_in, &payloadlen_in, buf, buflen); |
dvn | 0:96a5aefac643 | 99 | printf("message arrived %.*s\n", payloadlen_in, payload_in); |
dvn | 0:96a5aefac643 | 100 | } |
dvn | 0:96a5aefac643 | 101 | |
dvn | 0:96a5aefac643 | 102 | printf("publishing reading\n"); |
dvn | 0:96a5aefac643 | 103 | len = MQTTSerialize_publish(buf, buflen, 0, 0, 0, 0, topicString, payload, payloadlen); |
dvn | 0:96a5aefac643 | 104 | rc = mysock.send(buf, len); |
dvn | 0:96a5aefac643 | 105 | } |
dvn | 0:96a5aefac643 | 106 | |
dvn | 0:96a5aefac643 | 107 | printf("disconnecting\n"); |
dvn | 0:96a5aefac643 | 108 | len = MQTTSerialize_disconnect(buf, buflen); |
dvn | 0:96a5aefac643 | 109 | rc = mysock.send(buf, len); |
dvn | 0:96a5aefac643 | 110 | |
dvn | 0:96a5aefac643 | 111 | exit: |
dvn | 0:96a5aefac643 | 112 | eth.disconnect(); |
dvn | 0:96a5aefac643 | 113 | |
dvn | 0:96a5aefac643 | 114 | return 0; |
dvn | 0:96a5aefac643 | 115 | } |