Vergil Cola / Mbed OS HelloMQTT Featured

A Threaded Secure MQTT Client example. Uses MBED TLS for SSL/TLS connection. QoS0 only for now. Example has been tested with K64F connected via Ethernet.

Dependencies:   FP MQTTPacket

Fork of HelloMQTT by MQTT

MQTTThreadedClient.h@25:326f00faa092, 2017-03-27 (annotated)

Committer:
vpcola
Date:
Mon Mar 27 03:53:18 2017 +0000
Revision:
25:326f00faa092
Parent:
23:06fac173529e
Child:
26:4b21de8043a5
Added SSL/TLS code

Who changed what in which revision?

UserRevisionLine numberNew contents of line
vpcola 23:06fac173529e 1 #ifndef _MQTT_THREADED_CLIENT_H_
vpcola 23:06fac173529e 2 #define _MQTT_THREADED_CLIENT_H_
vpcola 23:06fac173529e 3
vpcola 23:06fac173529e 4 #include "mbed.h"
vpcola 23:06fac173529e 5 #include "rtos.h"
vpcola 23:06fac173529e 6 #include "MQTTPacket.h"
vpcola 23:06fac173529e 7 #include "NetworkInterface.h"
vpcola 23:06fac173529e 8 #include "FP.h"
vpcola 23:06fac173529e 9
vpcola 25:326f00faa092 10
vpcola 23:06fac173529e 11 #include <cstdio>
vpcola 23:06fac173529e 12 #include <string>
vpcola 23:06fac173529e 13 #include <map>
vpcola 23:06fac173529e 14
vpcola 23:06fac173529e 15 #define COMMAND_TIMEOUT 5000
vpcola 23:06fac173529e 16 #define DEFAULT_SOCKET_TIMEOUT 1000
vpcola 23:06fac173529e 17 #define MAX_MQTT_PACKET_SIZE 200
vpcola 23:06fac173529e 18 #define MAX_MQTT_PAYLOAD_SIZE 100
vpcola 23:06fac173529e 19
vpcola 23:06fac173529e 20 typedef enum { QOS0, QOS1, QOS2 } QoS;
vpcola 23:06fac173529e 21
vpcola 23:06fac173529e 22 // all failure return codes must be negative
vpcola 23:06fac173529e 23 typedef enum { BUFFER_OVERFLOW = -3, TIMEOUT = -2, FAILURE = -1, SUCCESS = 0 } returnCode;
vpcola 23:06fac173529e 24
vpcola 23:06fac173529e 25
vpcola 23:06fac173529e 26 typedef struct
vpcola 23:06fac173529e 27 {
vpcola 23:06fac173529e 28 QoS qos;
vpcola 23:06fac173529e 29 bool retained;
vpcola 23:06fac173529e 30 bool dup;
vpcola 23:06fac173529e 31 unsigned short id;
vpcola 23:06fac173529e 32 void *payload;
vpcola 23:06fac173529e 33 size_t payloadlen;
vpcola 23:06fac173529e 34 }Message, *pMessage;
vpcola 23:06fac173529e 35
vpcola 23:06fac173529e 36 // TODO:
vpcola 23:06fac173529e 37 // Merge this struct with the one above, in order to use the same
vpcola 23:06fac173529e 38 // data structure for sending and receiving. I need to simplify
vpcola 23:06fac173529e 39 // the PubMessage to not contain pointers like the one above.
vpcola 23:06fac173529e 40 typedef struct
vpcola 23:06fac173529e 41 {
vpcola 23:06fac173529e 42 char topic[100];
vpcola 23:06fac173529e 43 QoS qos;
vpcola 23:06fac173529e 44 unsigned short id;
vpcola 23:06fac173529e 45 size_t payloadlen;
vpcola 23:06fac173529e 46 char payload[MAX_MQTT_PAYLOAD_SIZE];
vpcola 23:06fac173529e 47 }PubMessage, *pPubMessage;
vpcola 23:06fac173529e 48
vpcola 23:06fac173529e 49 struct MessageData
vpcola 23:06fac173529e 50 {
vpcola 23:06fac173529e 51 MessageData(MQTTString &aTopicName, Message &aMessage) : message(aMessage), topicName(aTopicName)
vpcola 23:06fac173529e 52 { }
vpcola 23:06fac173529e 53 Message &message;
vpcola 23:06fac173529e 54 MQTTString &topicName;
vpcola 23:06fac173529e 55 };
vpcola 23:06fac173529e 56
vpcola 23:06fac173529e 57 class PacketId
vpcola 23:06fac173529e 58 {
vpcola 23:06fac173529e 59 public:
vpcola 23:06fac173529e 60 PacketId()
vpcola 23:06fac173529e 61 {
vpcola 23:06fac173529e 62 next = 0;
vpcola 23:06fac173529e 63 }
vpcola 23:06fac173529e 64
vpcola 23:06fac173529e 65 int getNext()
vpcola 23:06fac173529e 66 {
vpcola 23:06fac173529e 67 return next = (next == MAX_PACKET_ID) ? 1 : ++next;
vpcola 23:06fac173529e 68 }
vpcola 23:06fac173529e 69
vpcola 23:06fac173529e 70 private:
vpcola 23:06fac173529e 71 static const int MAX_PACKET_ID = 65535;
vpcola 23:06fac173529e 72 int next;
vpcola 23:06fac173529e 73 };
vpcola 23:06fac173529e 74
vpcola 23:06fac173529e 75
vpcola 23:06fac173529e 76
vpcola 23:06fac173529e 77 class MQTTThreadedClient
vpcola 23:06fac173529e 78 {
vpcola 23:06fac173529e 79 public:
vpcola 25:326f00faa092 80 MQTTThreadedClient(NetworkInterface * aNetwork, const char * pem = NULL)
vpcola 23:06fac173529e 81 : network(aNetwork),
vpcola 25:326f00faa092 82 ssl_ca_pem(pem),
vpcola 23:06fac173529e 83 queue(32 * EVENTS_EVENT_SIZE),
vpcola 25:326f00faa092 84 isConnected(false)
vpcola 25:326f00faa092 85 {
vpcola 25:326f00faa092 86 DRBG_PERS = "mbed TLS MQTT client";
vpcola 23:06fac173529e 87 tcpSocket = new TCPSocket();
vpcola 25:326f00faa092 88 setupTLS();
vpcola 25:326f00faa092 89 }
vpcola 25:326f00faa092 90
vpcola 25:326f00faa092 91 ~MQTTThreadedClient()
vpcola 25:326f00faa092 92 {
vpcola 25:326f00faa092 93 // TODO: signal the thread to shutdown
vpcola 25:326f00faa092 94 freeTLS();
vpcola 25:326f00faa092 95
vpcola 25:326f00faa092 96 if (isConnected)
vpcola 25:326f00faa092 97 disconnect();
vpcola 25:326f00faa092 98
vpcola 23:06fac173529e 99 }
vpcola 23:06fac173529e 100
vpcola 25:326f00faa092 101
vpcola 23:06fac173529e 102 int connect(const char * host, uint16_t port, MQTTPacket_connectData & options);
vpcola 25:326f00faa092 103 void disconnect();
vpcola 25:326f00faa092 104
vpcola 23:06fac173529e 105 int publish(PubMessage& message);
vpcola 25:326f00faa092 106
vpcola 25:326f00faa092 107 void addTopicHandler(const char * topic, void (*function)(MessageData &));
vpcola 25:326f00faa092 108 template<typename T>
vpcola 25:326f00faa092 109 void addTopicHandler(const char * topic, T *object, void (T::*member)(MessageData &))
vpcola 25:326f00faa092 110 {
vpcola 25:326f00faa092 111 FP<void,MessageData &> fp;
vpcola 25:326f00faa092 112 fp.attach(object, member);
vpcola 25:326f00faa092 113
vpcola 25:326f00faa092 114 topicCBMap_t.insert(std::pair<std::string, FP<void,MessageData &> >(std::string(topicstr),fp));
vpcola 25:326f00faa092 115 }
vpcola 25:326f00faa092 116
vpcola 23:06fac173529e 117 int subscribe(const char * topic, QoS qos, void (*function)(MessageData &));
vpcola 23:06fac173529e 118 template<typename T>
vpcola 23:06fac173529e 119 int subscribe(const char * topicstr, QoS qos, T *object, void (T::*member)(MessageData &)) {
vpcola 23:06fac173529e 120 int rc = FAILURE;
vpcola 23:06fac173529e 121 int len = 0;
vpcola 23:06fac173529e 122
vpcola 23:06fac173529e 123 MQTTString topic = {(char*)topicstr, {0, 0}};
vpcola 25:326f00faa092 124 printf("Subscribing to topic [%s]\r\n", topicstr);
vpcola 25:326f00faa092 125
vpcola 23:06fac173529e 126 if (!isConnected) {
vpcola 23:06fac173529e 127 printf("Session already connected!!\r\n");
vpcola 23:06fac173529e 128 return rc;
vpcola 23:06fac173529e 129 }
vpcola 23:06fac173529e 130
vpcola 23:06fac173529e 131 len = MQTTSerialize_subscribe(sendbuf, MAX_MQTT_PACKET_SIZE, 0, packetid.getNext(), 1, &topic, (int*)&qos);
vpcola 23:06fac173529e 132 if (len <= 0) {
vpcola 23:06fac173529e 133 printf("Error serializing subscribe packet ...\r\n");
vpcola 23:06fac173529e 134 return rc;
vpcola 23:06fac173529e 135 }
vpcola 23:06fac173529e 136
vpcola 23:06fac173529e 137 if ((rc = sendPacket(len)) != SUCCESS) {
vpcola 23:06fac173529e 138 printf("Error sending subscribe packet [%d]\r\n", rc);
vpcola 23:06fac173529e 139 return rc;
vpcola 23:06fac173529e 140 }
vpcola 25:326f00faa092 141 printf("Waiting for subscription ack ...\r\n");
vpcola 23:06fac173529e 142 // Wait for SUBACK, dropping packets read along the way ...
vpcola 23:06fac173529e 143 if (readUntil(SUBACK, COMMAND_TIMEOUT) == SUBACK) { // wait for suback
vpcola 23:06fac173529e 144 int count = 0, grantedQoS = -1;
vpcola 23:06fac173529e 145 unsigned short mypacketid;
vpcola 23:06fac173529e 146 if (MQTTDeserialize_suback(&mypacketid, 1, &count, &grantedQoS, readbuf, MAX_MQTT_PACKET_SIZE) == 1)
vpcola 23:06fac173529e 147 rc = grantedQoS; // 0, 1, 2 or 0x80
vpcola 23:06fac173529e 148 // For as long as we do not get 0x80 ..
vpcola 23:06fac173529e 149 if (rc != 0x80) {
vpcola 23:06fac173529e 150 // Add message handlers to the map
vpcola 23:06fac173529e 151 FP<void,MessageData &> fp;
vpcola 23:06fac173529e 152 fp.attach(object, member);
vpcola 23:06fac173529e 153
vpcola 23:06fac173529e 154 topicCBMap.insert(std::pair<std::string, FP<void,MessageData &> >(std::string(topicstr),fp));
vpcola 23:06fac173529e 155
vpcola 23:06fac173529e 156 // Reset connection timers here ...
vpcola 23:06fac173529e 157 resetConnectionTimer();
vpcola 25:326f00faa092 158 printf("Successfully subscribed to %s ...\r\n", topicstr);
vpcola 23:06fac173529e 159 rc = SUCCESS;
vpcola 23:06fac173529e 160 }
vpcola 23:06fac173529e 161 } else
vpcola 25:326f00faa092 162 {
vpcola 25:326f00faa092 163 printf("Failed to subscribe to topic %s (ack not received) ...\r\n", topicstr);
vpcola 23:06fac173529e 164 rc = FAILURE;
vpcola 25:326f00faa092 165 }
vpcola 23:06fac173529e 166
vpcola 23:06fac173529e 167 return rc;
vpcola 23:06fac173529e 168 }
vpcola 23:06fac173529e 169
vpcola 23:06fac173529e 170 // the listener thread ...
vpcola 23:06fac173529e 171 void startListener();
vpcola 23:06fac173529e 172
vpcola 23:06fac173529e 173 protected:
vpcola 23:06fac173529e 174 int connect(MQTTPacket_connectData& options);
vpcola 23:06fac173529e 175 int handlePublishMsg();
vpcola 23:06fac173529e 176
vpcola 23:06fac173529e 177
vpcola 23:06fac173529e 178 private:
vpcola 23:06fac173529e 179 NetworkInterface * network;
vpcola 25:326f00faa092 180 const char * ssl_ca_pem;
vpcola 23:06fac173529e 181 TCPSocket * tcpSocket;
vpcola 23:06fac173529e 182 PacketId packetid;
vpcola 25:326f00faa092 183 const char *DRBG_PERS;
vpcola 25:326f00faa092 184 nsapi_error_t _error;
vpcola 25:326f00faa092 185 // Connection options
vpcola 25:326f00faa092 186 std::string host;
vpcola 25:326f00faa092 187 uint16_t port;
vpcola 25:326f00faa092 188 MQTTPacket_connectData connect_options;
vpcola 25:326f00faa092 189
vpcola 25:326f00faa092 190
vpcola 23:06fac173529e 191 // Event queue
vpcola 23:06fac173529e 192 EventQueue queue;
vpcola 23:06fac173529e 193 bool isConnected;
vpcola 23:06fac173529e 194
vpcola 23:06fac173529e 195 // TODO: Because I'm using a map, I can only have one handler
vpcola 23:06fac173529e 196 // for each topic (one that's mapped to the topic string).
vpcola 23:06fac173529e 197 // Attaching another handler on the same topic is not possible.
vpcola 23:06fac173529e 198 // In the future, use a vector instead of maps to allow multiple
vpcola 23:06fac173529e 199 // handlers for the same topic.
vpcola 23:06fac173529e 200 std::map<std::string, FP<void, MessageData &> > topicCBMap;
vpcola 25:326f00faa092 201 std::map<std::string, FP<void, MessageData &> > topicCBMap_t;
vpcola 25:326f00faa092 202
vpcola 23:06fac173529e 203 unsigned char sendbuf[MAX_MQTT_PACKET_SIZE];
vpcola 23:06fac173529e 204 unsigned char readbuf[MAX_MQTT_PACKET_SIZE];
vpcola 23:06fac173529e 205
vpcola 23:06fac173529e 206 unsigned int keepAliveInterval;
vpcola 23:06fac173529e 207 Timer comTimer;
vpcola 23:06fac173529e 208
vpcola 25:326f00faa092 209 // SSL/TLS functions
vpcola 25:326f00faa092 210 void setupTLS();
vpcola 25:326f00faa092 211 int initTLS();
vpcola 25:326f00faa092 212 void freeTLS();
vpcola 25:326f00faa092 213 int doTLSHandshake();
vpcola 25:326f00faa092 214
vpcola 25:326f00faa092 215 int processSubscriptions();
vpcola 23:06fac173529e 216 int readPacket();
vpcola 23:06fac173529e 217 int sendPacket(size_t length);
vpcola 23:06fac173529e 218 int readPacketLength(int* value);
vpcola 23:06fac173529e 219 int readUntil(int packetType, int timeout);
vpcola 23:06fac173529e 220 int readBytesToBuffer(char * buffer, size_t size, int timeout);
vpcola 23:06fac173529e 221 int sendBytesFromBuffer(char * buffer, size_t size, int timeout);
vpcola 23:06fac173529e 222 bool isTopicMatched(char* topic, MQTTString& topicName);
vpcola 23:06fac173529e 223 int sendPublish(PubMessage& message);
vpcola 23:06fac173529e 224 void resetConnectionTimer();
vpcola 23:06fac173529e 225 void sendPingRequest();
vpcola 23:06fac173529e 226 bool hasConnectionTimedOut();
vpcola 23:06fac173529e 227
vpcola 23:06fac173529e 228 };
vpcola 23:06fac173529e 229
vpcola 23:06fac173529e 230 #endif