Merge pull request #10 from adafruit/3.1.1

MQTT 3.1.1 Support

Adafruit_MQTT.cpp

@@ -26,7 +26,7 @@ void printBuffer(uint8_t *buffer, uint8_t len) {
   for (uint8_t i=0; i<len; i++) {
     if (isprint(buffer[i]))
       DEBUG_PRINTER.write(buffer[i]);
-    else  
+    else
       DEBUG_PRINTER.print(" ");
     DEBUG_PRINTER.print(F(" [0x"));
     if (buffer[i] < 0x10)
@@ -70,62 +70,97 @@ static uint8_t *stringprint_P(uint8_t *p, const char *s, uint16_t maxlen=0) {
 
 // Adafruit_MQTT Definition ////////////////////////////////////////////////////
 
-Adafruit_MQTT::Adafruit_MQTT(const char *server, uint16_t port, const char *cid,
+Adafruit_MQTT::Adafruit_MQTT(const char *server,
-                             const char *user, const char *pass) {
+                             uint16_t port,
+                             const char *cid,
+                             const char *user,
+                             const char *pass) {
   servername = server;
   portnum = port;
   clientid = cid;
   username = user;
   password = pass;
 
+  // reset subscriptions
   for (uint8_t i=0; i<MAXSUBSCRIPTIONS; i++) {
     subscriptions[i] = 0;
   }
+
+  packet_id_counter = 0;
+
 }
 
-Adafruit_MQTT::Adafruit_MQTT(const __FlashStringHelper *server, uint16_t port, const __FlashStringHelper *cid,
+Adafruit_MQTT::Adafruit_MQTT(const __FlashStringHelper *server,
-                             const __FlashStringHelper *user, const __FlashStringHelper *pass) {
+                             uint16_t port,
+                             const __FlashStringHelper *cid,
+                             const __FlashStringHelper *user,
+                             const __FlashStringHelper *pass) {
+
   servername = (const char *)server;
   portnum = port;
   clientid = (const char *)cid;
   username = (const char *)user;
   password = (const char *)pass;
 
+  // reset subscriptions
   for (uint8_t i=0; i<MAXSUBSCRIPTIONS; i++) {
     subscriptions[i] = 0;
   }
+
+  packet_id_counter = 0;
+
 }
 
-
+Adafruit_MQTT::Adafruit_MQTT(const char *server,
-/*
+                             uint16_t port,
-Adafruit_MQTT::Adafruit_MQTT(char *server, uint16_t port, char *cid, char *user, char *pass) {
+                             const char *user,
-  strncpy(servername, server, SERVERNAME_SIZE);
+                             const char *pass) {
-  servername[SERVERNAME_SIZE-1] = 0;
+  servername = server;
   portnum = port;
-  serverip = 0;
+  clientid = "";
+  username = user;
+  password = pass;
 
-  strncpy(clientid, cid, CLIENTID_SIZE);
+  // reset subscriptions
-  clientid[CLIENTID_SIZE-1] = 0;
+  for (uint8_t i=0; i<MAXSUBSCRIPTIONS; i++) {
+    subscriptions[i] = 0;
+  }
 
-  strncpy(username, user, USERNAME_SIZE);
+  packet_id_counter = 0;
-  username[USERNAME_SIZE-1] = 0;
+
+}
+
+Adafruit_MQTT::Adafruit_MQTT(const __FlashStringHelper *server,
+                             uint16_t port,
+                             const __FlashStringHelper *user,
+                             const __FlashStringHelper *pass) {
+
+  servername = (const char *)server;
+  portnum = port;
+  clientid = "";
+  username = (const char *)user;
+  password = (const char *)pass;
+
+  // reset subscriptions
+  for (uint8_t i=0; i<MAXSUBSCRIPTIONS; i++) {
+    subscriptions[i] = 0;
+  }
+
+  packet_id_counter = 0;
 
-  strncpy(password, pass, PASSWORD_SIZE);
-  password[PASSWORD_SIZE-1] = 0;
 }
-*/
 
 int8_t Adafruit_MQTT::connect() {
   // Connect to the server.
   if (!connectServer())
     return -1;
-  
+
   // Construct and send connect packet.
   uint8_t len = connectPacket(buffer);
   if (!sendPacket(buffer, len))
     return -1;
 
-  // Read connect response packet and verify it  
+  // Read connect response packet and verify it
   len = readPacket(buffer, 4, CONNECT_TIMEOUT_MS);
   if (len != 4)
     return -1;
@@ -143,14 +178,19 @@ int8_t Adafruit_MQTT::connect() {
     uint8_t len = subscribePacket(buffer, subscriptions[i]->topic, subscriptions[i]->qos);
     if (!sendPacket(buffer, len))
       return -1;
-    
+
-    // Get SUBACK
+    // Check for SUBACK if using MQTT 3.1.1 or higher
-    len = readPacket(buffer, 5, CONNECT_TIMEOUT_MS);
+    // TODO: The Server is permitted to start sending PUBLISH packets matching the
-    DEBUG_PRINT(F("SUBACK:\t"));
+    // Subscription before the Server sends the SUBACK Packet.
-    DEBUG_PRINTBUFFER(buffer, len);
+    // if(MQTT_PROTOCOL_LEVEL > 3) {
-    if ((len != 5) || (buffer[0] != (MQTT_CTRL_SUBACK << 4))) {
+    //   len = readPacket(buffer, 5, CONNECT_TIMEOUT_MS);
-      return 6;  // failure to subscribe
+    //   DEBUG_PRINT(F("SUBACK:\t"));
-    }
+    //   DEBUG_PRINTBUFFER(buffer, len);
+    //   if ((len != 5) || (buffer[0] != (MQTT_CTRL_SUBACK << 4))) {
+    //     return 6;  // failure to subscribe
+    //   }
+    // }
+
   }
 
   return 0;
@@ -169,12 +209,24 @@ const __FlashStringHelper* Adafruit_MQTT::connectErrorString(int8_t code) {
    }
 }
 
+bool Adafruit_MQTT::disconnect() {
+
+  // Construct and send disconnect packet.
+  uint8_t len = disconnectPacket(buffer);
+  if (! sendPacket(buffer, len))
+    DEBUG_PRINTLN(F("Unable to send disconnect packet"));
+
+  return disconnectServer();
+
+}
+
+
 bool Adafruit_MQTT::publish(const char *topic, const char *data, uint8_t qos) {
   // Construct and send publish packet.
   uint8_t len = publishPacket(buffer, topic, data, qos);
   if (!sendPacket(buffer, len))
     return false;
-  
+
   // If QOS level is high enough verify the response packet.
   if (qos > 0) {
     len = readPacket(buffer, 4, PUBLISH_TIMEOUT_MS);
@@ -186,6 +238,22 @@ bool Adafruit_MQTT::publish(const char *topic, const char *data, uint8_t qos) {
   return true;
 }
 
+bool Adafruit_MQTT::will(const char *topic, const char *payload, uint8_t qos, uint8_t retain) {
+
+  if (connected()) {
+    DEBUG_PRINT(F("Will defined after connect"));
+    return false;
+  }
+
+  will_topic = topic;
+  will_payload = payload;
+  will_qos = qos;
+  will_retain = retain;
+
+  return true;
+
+}
+
 bool Adafruit_MQTT::subscribe(Adafruit_MQTT_Subscribe *sub) {
   uint8_t i;
   // see if we are already subscribed
@@ -209,6 +277,50 @@ bool Adafruit_MQTT::subscribe(Adafruit_MQTT_Subscribe *sub) {
   return false;
 }
 
+bool Adafruit_MQTT::unsubscribe(Adafruit_MQTT_Subscribe *sub) {
+  uint8_t i;
+
+  // see if we are already subscribed
+  for (i=0; i<MAXSUBSCRIPTIONS; i++) {
+
+    if (subscriptions[i] == sub) {
+
+      DEBUG_PRINTLN(F("Found matching subscription and attempting to unsubscribe."));
+
+      // Construct and send unsubscribe packet.
+      uint8_t len = unsubscribePacket(buffer, subscriptions[i]->topic);
+
+      // sending unsubscribe failed
+      if (! sendPacket(buffer, len))
+        return false;
+
+      // if QoS for this subscription is 1 or 2, we need
+      // to wait for the unsuback to confirm unsubscription
+      if(subscriptions[i]->qos > 0 && MQTT_PROTOCOL_LEVEL > 3) {
+
+        // wait for UNSUBACK
+        len = readPacket(buffer, 5, CONNECT_TIMEOUT_MS);
+        DEBUG_PRINT(F("UNSUBACK:\t"));
+        DEBUG_PRINTBUFFER(buffer, len);
+
+        if ((len != 5) || (buffer[0] != (MQTT_CTRL_UNSUBACK << 4))) {
+          return false;  // failure to unsubscribe
+        }
+
+      }
+
+      subscriptions[i] = 0;
+      return true;
+
+    }
+
+  }
+
+  // subscription not found, so we are unsubscribed
+  return true;
+
+}
+
 Adafruit_MQTT_Subscribe *Adafruit_MQTT::readSubscription(int16_t timeout) {
   uint8_t i, topiclen, datalen;
 
@@ -233,7 +345,7 @@ Adafruit_MQTT_Subscribe *Adafruit_MQTT::readSubscription(int16_t timeout) {
       // to make comparison case insensitive.
       if (strncasecmp_P((char*)buffer+4, subscriptions[i]->topic, topiclen) == 0) {
         DEBUG_PRINT(F("Found sub #")); DEBUG_PRINTLN(i);
-        break;        
+        break;
       }
     }
   }
@@ -256,18 +368,27 @@ Adafruit_MQTT_Subscribe *Adafruit_MQTT::readSubscription(int16_t timeout) {
   return subscriptions[i];
 }
 
-bool Adafruit_MQTT::ping(uint8_t times) {
+void Adafruit_MQTT::flushIncoming(uint16_t timeout) {
-  while (times) {
+  // flush input!
+  DEBUG_PRINTLN(F("Flushing input buffer"));
+  while (readPacket(buffer, MAXBUFFERSIZE, timeout));
+}
+
+bool Adafruit_MQTT::ping(uint8_t num) {
+  flushIncoming(100);
+
+  while (num--) {
     // Construct and send ping packet.
     uint8_t len = pingPacket(buffer);
     if (!sendPacket(buffer, len))
-      return false;
+      continue;
     
     // Process ping reply.
     len = readPacket(buffer, 2, PING_TIMEOUT_MS);
     if (buffer[0] == (MQTT_CTRL_PINGRESP << 4))
-      return true;  
+      return true;
   }
+    
   return false;
 }
 
@@ -287,31 +408,64 @@ uint8_t Adafruit_MQTT::connectPacket(uint8_t *packet) {
   p+=2;
   // fill in packet[1] last
 
-#if (MQTT_PROTOCOL_LEVEL == 4)
+#if MQTT_PROTOCOL_LEVEL == 3
-  p = stringprint_P(p, PSTR("MQTT"));
+    p = stringprint_P(p, PSTR("MQIsdp"));
-#elif (MQTT_PROTOCOL_LEVEL == 3)
+#elif MQTT_PROTOCOL_LEVEL == 4
-  p = stringprint_P(p, PSTR("MQIsdp"));
+    p = stringprint_P(p, PSTR("MQTT"));
 #else
-  #error "No MQTT version selected!"
+    #error "MQTT level not supported"
 #endif
 
   p[0] = MQTT_PROTOCOL_LEVEL;
   p++;
 
+  // always clean the session
   p[0] = MQTT_CONN_CLEANSESSION;
+
+  // set the will flags if needed
+  if (will_topic && pgm_read_byte(will_topic) != 0) {
+
+    p[0] |= MQTT_CONN_WILLFLAG;
+
+    if(will_qos == 1)
+      p[0] |= MQTT_CONN_WILLQOS_1;
+    else if(will_qos == 2)
+      p[0] |= MQTT_CONN_WILLQOS_2;
+
+    if(will_retain == 1)
+      p[0] |= MQTT_CONN_WILLRETAIN;
+
+  }
+
   if (pgm_read_byte(username) != 0)
     p[0] |= MQTT_CONN_USERNAMEFLAG;
   if (pgm_read_byte(password) != 0)
     p[0] |= MQTT_CONN_PASSWORDFLAG;
   p++;
-  // TODO: add WILL support?
 
   p[0] = MQTT_CONN_KEEPALIVE >> 8;
   p++;
   p[0] = MQTT_CONN_KEEPALIVE & 0xFF;
   p++;
 
-  p = stringprint_P(p, clientid, 23);  // Limit client ID to first 23 characters.
+  if(MQTT_PROTOCOL_LEVEL == 3) {
+    p = stringprint_P(p, clientid, 23);  // Limit client ID to first 23 characters.
+  } else {
+    if (pgm_read_byte(clientid) != 0) {
+      p = stringprint_P(p, clientid);
+    } else {
+      p[0] = 0x0;
+      p++;
+      p[0] = 0x0;
+      p++;
+      DEBUG_PRINTLN(F("SERVER GENERATING CLIENT ID"));
+    }
+  }
+
+  if (will_topic && pgm_read_byte(will_topic) != 0) {
+    p = stringprint_P(p, will_topic);
+    p = stringprint_P(p, will_payload);
+  }
 
   if (pgm_read_byte(username) != 0) {
     p = stringprint_P(p, username);
@@ -337,6 +491,16 @@ uint8_t Adafruit_MQTT::publishPacket(uint8_t *packet, const char *topic,
   // fill in packet[1] last
   p+=2;
 
+  // add packet identifier. used for checking PUBACK in QOS > 0
+  if(qos > 0) {
+    p[0] = (packet_id_counter >> 8) & 0xFF;
+    p[1] = packet_id_counter & 0xFF;
+    p+=2;
+
+    // increment the packet id
+    packet_id_counter++;
+  }
+
   p = stringprint_P(p, topic);
 
   memcpy(p, data, strlen(data));
@@ -357,11 +521,14 @@ uint8_t Adafruit_MQTT::subscribePacket(uint8_t *packet, const char *topic,
   // fill in packet[1] last
   p+=2;
 
-  // put in a message id,
+  // packet identifier. used for checking SUBACK
-  p[0] = 0xAD;
+  p[0] = (packet_id_counter >> 8) & 0xFF;
-  p[1] = 0xAF;
+  p[1] = packet_id_counter & 0xFF;
   p+=2;
 
+  // increment the packet id
+  packet_id_counter++;
+
   p = stringprint_P(p, topic);
 
   p[0] = qos;
@@ -374,6 +541,33 @@ uint8_t Adafruit_MQTT::subscribePacket(uint8_t *packet, const char *topic,
   return len;
 }
 
+uint8_t Adafruit_MQTT::unsubscribePacket(uint8_t *packet, const char *topic) {
+
+  uint8_t *p = packet;
+  uint16_t len;
+
+  p[0] = MQTT_CTRL_UNSUBSCRIBE << 4 | 0x1;
+  // fill in packet[1] last
+  p+=2;
+
+  // packet identifier. used for checking UNSUBACK
+  p[0] = (packet_id_counter >> 8) & 0xFF;
+  p[1] = packet_id_counter & 0xFF;
+  p+=2;
+
+  // increment the packet id
+  packet_id_counter++;
+
+  p = stringprint_P(p, topic);
+
+  len = p - packet;
+  packet[1] = len-2; // don't include the 2 bytes of fixed header data
+  DEBUG_PRINTLN(F("MQTT unsubscription packet:"));
+  DEBUG_PRINTBUFFER(buffer, len);
+  return len;
+
+}
+
 uint8_t Adafruit_MQTT::pingPacket(uint8_t *packet) {
   packet[0] = MQTT_CTRL_PINGREQ << 4;
   packet[1] = 0;
@@ -382,6 +576,13 @@ uint8_t Adafruit_MQTT::pingPacket(uint8_t *packet) {
   return 2;
 }
 
+uint8_t Adafruit_MQTT::disconnectPacket(uint8_t *packet) {
+  packet[0] = MQTT_CTRL_DISCONNECT << 4;
+  packet[1] = 0;
+  DEBUG_PRINTLN(F("MQTT disconnect packet:"));
+  DEBUG_PRINTBUFFER(buffer, 2);
+  return 2;
+}
 
 // Adafruit_MQTT_Publish Definition ////////////////////////////////////////////
 

Adafruit_MQTT.h

@@ -48,20 +48,27 @@
 // Use 3 (MQTT 3.0) or 4 (MQTT 3.1.1)
 #define MQTT_PROTOCOL_LEVEL 4
 
-#define MQTT_CTRL_CONNECT 0x01
+#define MQTT_CTRL_CONNECT     0x1
-#define MQTT_CTRL_CONNECTACK 0x02
+#define MQTT_CTRL_CONNECTACK  0x2
-#define MQTT_CTRL_PUBLISH 0x03
+#define MQTT_CTRL_PUBLISH     0x3
-#define MQTT_CTRL_SUBSCRIBE 0x08
+#define MQTT_CTRL_PUBACK      0x4
-#define MQTT_CTRL_SUBACK 0x09
+#define MQTT_CTRL_PUBREC      0x5
-#define MQTT_CTRL_PINGREQ 0x0C
+#define MQTT_CTRL_PUBREL      0x6
-#define MQTT_CTRL_PINGRESP 0x0D
+#define MQTT_CTRL_PUBCOMP     0x7
+#define MQTT_CTRL_SUBSCRIBE   0x8
+#define MQTT_CTRL_SUBACK      0x9
+#define MQTT_CTRL_UNSUBSCRIBE 0xA
+#define MQTT_CTRL_UNSUBACK    0xB
+#define MQTT_CTRL_PINGREQ     0xC
+#define MQTT_CTRL_PINGRESP    0xD
+#define MQTT_CTRL_DISCONNECT  0xE
 
 #define MQTT_QOS_1 0x1
 #define MQTT_QOS_0 0x0
 
 #define CONNECT_TIMEOUT_MS 3000
 #define PUBLISH_TIMEOUT_MS 500
-#define PING_TIMEOUT_MS 500
+#define PING_TIMEOUT_MS    500
 
 // Adjust as necessary, in seconds.  Default to 5 minutes.
 #define MQTT_CONN_KEEPALIVE 300
@@ -71,15 +78,15 @@
 // 23 char client ID.
 #define MAXBUFFERSIZE (125)
 
-#define MQTT_CONN_USERNAMEFLAG 0x80
+#define MQTT_CONN_USERNAMEFLAG    0x80
-#define MQTT_CONN_PASSWORDFLAG 0x40
+#define MQTT_CONN_PASSWORDFLAG    0x40
-#define MQTT_CONN_WILLRETAIN   0x20
+#define MQTT_CONN_WILLRETAIN      0x20
-#define MQTT_CONN_WILLQOS   0x08
+#define MQTT_CONN_WILLQOS_1       0x08
-#define MQTT_CONN_WILLFLAG   0x04
+#define MQTT_CONN_WILLQOS_2       0x18
-#define MQTT_CONN_CLEANSESSION   0x02
+#define MQTT_CONN_WILLFLAG        0x04
+#define MQTT_CONN_CLEANSESSION    0x02
 
-// how many subscriptions we want to be able to
+// how many subscriptions we want to be able to track
-// track
 #define MAXSUBSCRIPTIONS 5
 
 // how much data we save in a subscription object
@@ -93,10 +100,24 @@ class Adafruit_MQTT_Subscribe;  // forward decl
 
 class Adafruit_MQTT {
  public:
-  Adafruit_MQTT(const char *server, uint16_t port, const char *cid,
+  Adafruit_MQTT(const char *server,
-                const char *user, const char *pass);
+                uint16_t port,
-  Adafruit_MQTT(const __FlashStringHelper *server, uint16_t port, const __FlashStringHelper *cid,
+                const char *cid,
-                const __FlashStringHelper *user, const __FlashStringHelper *pass);
+                const char *user,
+                const char *pass);
+  Adafruit_MQTT(const __FlashStringHelper *server,
+                uint16_t port,
+                const __FlashStringHelper *cid,
+                const __FlashStringHelper *user,
+                const __FlashStringHelper *pass);
+  Adafruit_MQTT(const char *server,
+                uint16_t port,
+                const char *user,
+                const char *pass);
+  Adafruit_MQTT(const __FlashStringHelper *server,
+                uint16_t port,
+                const __FlashStringHelper *user,
+                const __FlashStringHelper *pass);
   virtual ~Adafruit_MQTT() {}
 
   // Connect to the MQTT server.  Returns 0 on success, otherwise an error code
@@ -118,13 +139,20 @@ class Adafruit_MQTT {
   // Serial.println without any further processing.
   const __FlashStringHelper* connectErrorString(int8_t code);
 
-  // Disconnect from the MQTT server.  Returns true if disconnected, false
+  // Sends MQTT disconnect packet and calls disconnectServer()
-  // otherwise.
+  bool disconnect();
-  virtual bool disconnect() = 0;  // Subclasses need to fill this in!
 
   // Return true if connected to the MQTT server, otherwise false.
   virtual bool connected() = 0;  // Subclasses need to fill this in!
 
+  // Set MQTT last will topic, payload, QOS, and retain. This needs
+  // to be called before connect() because it is sent as part of the
+  // connect control packet.
+  bool will(const char *topic, const char *payload, uint8_t qos = 0, uint8_t retain = 0);
+  bool will(const __FlashStringHelper *topic, const char *payload, uint8_t qos = 0, uint8_t retain = 0) {
+    return will((const char *)topic, payload, qos, retain);
+  }
+
   // Publish a message to a topic using the specified QoS level.  Returns true
   // if the message was published, false otherwise.
   // The topic must be stored in PROGMEM. It can either be a
@@ -140,15 +168,17 @@ class Adafruit_MQTT {
   // is made is not currently supported.
   bool subscribe(Adafruit_MQTT_Subscribe *sub);
 
+  // Unsubscribe from a previously subscribed MQTT topic.
+  bool unsubscribe(Adafruit_MQTT_Subscribe *sub);
+
   // Check if any subscriptions have new messages.  Will return a reference to
   // an Adafruit_MQTT_Subscribe object which has a new message.  Should be called
   // in the sketch's loop function to ensure new messages are recevied.  Note
   // that subscribe should be called first for each topic that receives messages!
   Adafruit_MQTT_Subscribe *readSubscription(int16_t timeout=0);
 
-  // Ping the server to ensure the connection is still alive.  Returns true if
+  // Ping the server to ensure the connection is still alive.
-  // successful, otherwise false.
+  bool ping(uint8_t n = 1);
-  bool ping(uint8_t t);
 
  protected:
   // Interface that subclasses need to implement:
@@ -156,6 +186,9 @@ class Adafruit_MQTT {
   // Connect to the server and return true if successful, false otherwise.
   virtual bool connectServer() = 0;
 
+  // Disconnect from the MQTT server.  Returns true if disconnected, false otherwise.
+  virtual bool disconnectServer() = 0;  // Subclasses need to fill this in!
+
   // Send data to the server specified by the buffer and length of data.
   virtual bool sendPacket(uint8_t *buffer, uint8_t len) = 0;
 
@@ -172,15 +205,24 @@ class Adafruit_MQTT {
   const char *clientid;
   const char *username;
   const char *password;
+  const char *will_topic;
+  const char *will_payload;
+  uint8_t will_qos;
+  uint8_t will_retain;
   uint8_t buffer[MAXBUFFERSIZE];  // one buffer, used for all incoming/outgoing
+  uint16_t packet_id_counter;
 
  private:
   Adafruit_MQTT_Subscribe *subscriptions[MAXSUBSCRIPTIONS];
 
+  void    flushIncoming(uint16_t timeout);
+
   // Functions to generate MQTT packets.
   uint8_t connectPacket(uint8_t *packet);
+  uint8_t disconnectPacket(uint8_t *packet);
   uint8_t publishPacket(uint8_t *packet, const char *topic, const char *payload, uint8_t qos);
   uint8_t subscribePacket(uint8_t *packet, const char *topic, uint8_t qos);
+  uint8_t unsubscribePacket(uint8_t *packet, const char *topic);
   uint8_t pingPacket(uint8_t *packet);
 };
 

Adafruit_MQTT_CC3000.h

@@ -43,6 +43,12 @@ class Adafruit_MQTT_CC3000 : public Adafruit_MQTT {
     cc3000(cc3k)
   {}
 
+  Adafruit_MQTT_CC3000(Adafruit_CC3000 *cc3k, const char *server, uint16_t port,
+                       const char *user, const char *pass):
+    Adafruit_MQTT(server, port, user, pass),
+    cc3000(cc3k)
+  {}
+
   bool connectServer() {
     uint32_t ip = 0;
 
@@ -81,7 +87,7 @@ class Adafruit_MQTT_CC3000 : public Adafruit_MQTT {
     return mqttclient.connected();
   }
 
-  bool disconnect() {
+  bool disconnectServer() {
     if (connected()) {
       return (mqttclient.close() == 0);
     }

Adafruit_MQTT_Client.cpp

@@ -33,7 +33,7 @@ bool Adafruit_MQTT_Client::connectServer() {
   return r != 0;
 }
 
-bool Adafruit_MQTT_Client::disconnect() {
+bool Adafruit_MQTT_Client::disconnectServer() {
   // Stop connection if connected and return success (stop has no indication of
   // failure).
   if (client->connected()) {

Adafruit_MQTT_Client.h

@@ -36,14 +36,19 @@
 class Adafruit_MQTT_Client : public Adafruit_MQTT {
  public:
   Adafruit_MQTT_Client(Client *client, const char *server, uint16_t port,
-                       const char *cid, const char *user,
+                       const char *cid, const char *user, const char *pass):
-                       const char *pass):
     Adafruit_MQTT(server, port, cid, user, pass),
     client(client)
   {}
 
+  Adafruit_MQTT_Client(Client *client, const char *server, uint16_t port,
+                       const char *user, const char *pass):
+    Adafruit_MQTT(server, port, user, pass),
+    client(client)
+  {}
+
   bool connectServer();
-  bool disconnect();
+  bool disconnectServer();
   bool connected();
   uint16_t readPacket(uint8_t *buffer, uint8_t maxlen, int16_t timeout,
                       bool checkForValidPubPacket = false);

Adafruit_MQTT_FONA.h

@@ -41,6 +41,12 @@ class Adafruit_MQTT_FONA : public Adafruit_MQTT {
     fona(f)
   {}
 
+  Adafruit_MQTT_FONA(Adafruit_FONA *f, const char *server, uint16_t port,
+                     const char *user, const char *pass):
+    Adafruit_MQTT(server, port, user, pass),
+    fona(f)
+  {}
+
   bool connectServer() {
     char server[40];
     strncpy_P(server, servername, 40);
@@ -51,7 +57,7 @@ class Adafruit_MQTT_FONA : public Adafruit_MQTT {
     return fona->TCPconnect(server, portnum);
   }
 
-  bool disconnect() {
+  bool disconnectServer() {
     return fona->TCPclose();
   }
 

examples/mqtt_cc3k/mqtt_cc3k.ino

@@ -45,18 +45,14 @@
 // Setup the main CC3000 class, just like a normal CC3000 sketch.
 Adafruit_CC3000 cc3000 = Adafruit_CC3000(ADAFRUIT_CC3000_CS, ADAFRUIT_CC3000_IRQ, ADAFRUIT_CC3000_VBAT);
 
-// Store the MQTT server, client ID, username, and password in flash memory.
+// Store the MQTT server, username, and password in flash memory.
 // This is required for using the Adafruit MQTT library.
 const char MQTT_SERVER[] PROGMEM    = AIO_SERVER;
-// Set a unique MQTT client ID using the AIO key + the date and time the sketch
-// was compiled (so this should be unique across multiple devices for a user,
-// alternatively you can manually set this to a GUID or other random value).
-const char MQTT_CLIENTID[] PROGMEM  = __TIME__ AIO_USERNAME;
 const char MQTT_USERNAME[] PROGMEM  = AIO_USERNAME;
 const char MQTT_PASSWORD[] PROGMEM  = AIO_KEY;
 
 // Setup the CC3000 MQTT class by passing in the CC3000 class and MQTT server and login details.
-Adafruit_MQTT_CC3000 mqtt(&cc3000, MQTT_SERVER, AIO_SERVERPORT, MQTT_CLIENTID, MQTT_USERNAME, MQTT_PASSWORD);
+Adafruit_MQTT_CC3000 mqtt(&cc3000, MQTT_SERVER, AIO_SERVERPORT, MQTT_USERNAME, MQTT_PASSWORD);
 
 // You don't need to change anything below this line!
 #define halt(s) { Serial.println(F( s )); while(1);  }
@@ -108,16 +104,6 @@ void loop() {
   // connection and automatically reconnect when disconnected).  See the MQTT_connect
   // function definition further below.
   MQTT_connect();
- 
-  // Try to ping the MQTT server
-  /*
-  if (! mqtt.ping(3) ) {
-    // MQTT pings failed, let's reconnect by forcing a watchdog reset.
-    Serial.println("Ping fail! Resetting...");
-    Watchdog.enable(8000);
-    delay(10000);
-  }
-  */
 
   // this is our 'wait for incoming subscription packets' busy subloop
   Adafruit_MQTT_Subscribe *subscription;
@@ -137,6 +123,12 @@ void loop() {
   } else {
     Serial.println(F("OK!"));
   }
+
+  // ping the server to keep the mqtt connection alive
+  if(! mqtt.ping()) {
+    Serial.println(F("MQTT Ping failed."));
+  }
+
 }
 
 // Function to connect and reconnect as necessary to the MQTT server.

examples/mqtt_esp8266/mqtt_esp8266.ino

@@ -35,18 +35,14 @@
 // Create an ESP8266 WiFiClient class to connect to the MQTT server.
 WiFiClient client;
 
-// Store the MQTT server, client ID, username, and password in flash memory.
+// Store the MQTT server, username, and password in flash memory.
 // This is required for using the Adafruit MQTT library.
 const char MQTT_SERVER[] PROGMEM    = AIO_SERVER;
-// Set a unique MQTT client ID using the AIO key + the date and time the sketch
-// was compiled (so this should be unique across multiple devices for a user,
-// alternatively you can manually set this to a GUID or other random value).
-const char MQTT_CLIENTID[] PROGMEM  = __TIME__ AIO_USERNAME;
 const char MQTT_USERNAME[] PROGMEM  = AIO_USERNAME;
 const char MQTT_PASSWORD[] PROGMEM  = AIO_KEY;
 
 // Setup the MQTT client class by passing in the WiFi client and MQTT server and login details.
-Adafruit_MQTT_Client mqtt(&client, MQTT_SERVER, AIO_SERVERPORT, MQTT_CLIENTID, MQTT_USERNAME, MQTT_PASSWORD);
+Adafruit_MQTT_Client mqtt(&client, MQTT_SERVER, AIO_SERVERPORT, MQTT_USERNAME, MQTT_PASSWORD);
 
 /****************************** Feeds ***************************************/
 
@@ -94,14 +90,6 @@ void loop() {
   // function definition further below.
   MQTT_connect();
 
-  // Try to ping the MQTT server
-  /*
-  if (! mqtt.ping(3) ) {
-    // MQTT pings failed, lets reconnect
-    Serial.println("Ping fail!");
-  }
-  */
-
   // this is our 'wait for incoming subscription packets' busy subloop
   Adafruit_MQTT_Subscribe *subscription;
   while ((subscription = mqtt.readSubscription(1000))) {
@@ -121,7 +109,13 @@ void loop() {
     Serial.println(F("OK!"));
   }
 
+  // ping the server to keep the mqtt connection alive
+  if(! mqtt.ping()) {
+    mqtt.disconnect();
+  }
+
   delay(1000);
+
 }
 
 // Function to connect and reconnect as necessary to the MQTT server.

examples/mqtt_ethernet/mqtt_ethernet.ino

@@ -91,13 +91,6 @@ void loop() {
   // connection and automatically reconnect when disconnected).  See the MQTT_connect
   // function definition further below.
   MQTT_connect();
- 
-  // Try to ping the MQTT server
-  if (! mqtt.ping(3) ) {
-    // MQTT pings failed, let's reconnect by forcing a watchdog reset.
-    Serial.println("Ping fail! Resetting...");
-    delay(10000);
-  }
 
   // this is our 'wait for incoming subscription packets' busy subloop
   Adafruit_MQTT_Subscribe *subscription;
@@ -117,6 +110,12 @@ void loop() {
   } else {
     Serial.println(F("OK!"));
   }
+
+  // ping the server to keep the mqtt connection alive
+  if(! mqtt.ping()) {
+    mqtt.disconnect();
+  }
+
 }
 
 // Function to connect and reconnect as necessary to the MQTT server.

examples/mqtt_fona/mqtt_fona.ino

@@ -52,18 +52,14 @@ Adafruit_FONA fona = Adafruit_FONA(FONA_RST);
 
 /************ Global State (you don't need to change this!) ******************/
 
-// Store the MQTT server, client ID, username, and password in flash memory.
+// Store the MQTT server, username, and password in flash memory.
 // This is required for using the Adafruit MQTT library.
 const char MQTT_SERVER[] PROGMEM    = AIO_SERVER;
-// Set a unique MQTT client ID using the AIO key + the date and time the sketch
-// was compiled (so this should be unique across multiple devices for a user,
-// alternatively you can manually set this to a GUID or other random value).
-const char MQTT_CLIENTID[] PROGMEM  = __TIME__ AIO_USERNAME;
 const char MQTT_USERNAME[] PROGMEM  = AIO_USERNAME;
 const char MQTT_PASSWORD[] PROGMEM  = AIO_KEY;
 
 // Setup the FONA MQTT class by passing in the FONA class and MQTT server and login details.
-Adafruit_MQTT_FONA mqtt(&fona, MQTT_SERVER, AIO_SERVERPORT, MQTT_CLIENTID, MQTT_USERNAME, MQTT_PASSWORD);
+Adafruit_MQTT_FONA mqtt(&fona, MQTT_SERVER, AIO_SERVERPORT, MQTT_USERNAME, MQTT_PASSWORD);
 
 // You don't need to change anything below this line!
 #define halt(s) { Serial.println(F( s )); while(1);  }
@@ -117,30 +113,10 @@ void loop() {
   // Make sure to reset watchdog every loop iteration!
   Watchdog.reset();
 
-  // check if we're still connected
+  // Ensure the connection to the MQTT server is alive (this will make the first
-  if (!fona.TCPconnected() || (txfailures >= MAXTXFAILURES)) {
+  // connection and automatically reconnect when disconnected).  See the MQTT_connect
-    Serial.println(F("Connecting to MQTT..."));
+  // function definition further below.
-    int8_t ret, retries = 5;
+  MQTT_connect();
-    while (retries && (ret = mqtt.connect()) != 0) {
-       Serial.println(mqtt.connectErrorString(ret));
-       Serial.println(F("Retrying MQTT connection"));
-       retries--;
-       if (retries == 0) halt("Resetting system");
-       delay(5000);
-    }
-    Serial.println(F("MQTT Connected!"));
-    txfailures = 0;
-  }
-
-
-  // Try to ping the MQTT server
-  /*
-  if (! mqtt.ping(3) ) {
-    // MQTT pings failed, lets reconnect
-    Serial.println("Ping fail!");
-  }
-  */
-
 
   // this is our 'wait for incoming subscription packets' busy subloop
   Adafruit_MQTT_Subscribe *subscription;
@@ -162,4 +138,31 @@ void loop() {
     Serial.println(F("OK!"));
     txfailures = 0;
   }
+
+  // ping the server to keep the mqtt connection alive
+  if(! mqtt.ping()) {
+    Serial.println(F("MQTT Ping failed."));
+  }
+
+}
+
+// Function to connect and reconnect as necessary to the MQTT server.
+// Should be called in the loop function and it will take care if connecting.
+void MQTT_connect() {
+  int8_t ret;
+
+  // Stop if already connected.
+  if (mqtt.connected()) {
+    return;
+  }
+
+  Serial.print("Connecting to MQTT... ");
+
+  while ((ret = mqtt.connect()) != 0) { // connect will return 0 for connected
+    Serial.println(mqtt.connectErrorString(ret));
+    Serial.println("Retrying MQTT connection in 5 seconds...");
+    mqtt.disconnect();
+    delay(5000);  // wait 5 seconds
+  }
+  Serial.println("MQTT Connected!");
 }

examples/mqtt_yun/mqtt_yun.ino

@@ -35,18 +35,14 @@
 // Create a YunClient instance to communicate using the Yun's brighe & Linux OS.
 YunClient client;
 
-// Store the MQTT server, client ID, username, and password in flash memory.
+// Store the MQTT server, username, and password in flash memory.
 // This is required for using the Adafruit MQTT library.
 const char MQTT_SERVER[] PROGMEM    = AIO_SERVER;
-// Set a unique MQTT client ID using the AIO key + the date and time the sketch
-// was compiled (so this should be unique across multiple devices for a user,
-// alternatively you can manually set this to a GUID or other random value).
-const char MQTT_CLIENTID[] PROGMEM  = __TIME__ AIO_USERNAME;
 const char MQTT_USERNAME[] PROGMEM  = AIO_USERNAME;
 const char MQTT_PASSWORD[] PROGMEM  = AIO_KEY;
 
 // Setup the MQTT client class by passing in the WiFi client and MQTT server and login details.
-Adafruit_MQTT_Client mqtt(&client, MQTT_SERVER, AIO_SERVERPORT, MQTT_CLIENTID, MQTT_USERNAME, MQTT_PASSWORD);
+Adafruit_MQTT_Client mqtt(&client, MQTT_SERVER, AIO_SERVERPORT, MQTT_USERNAME, MQTT_PASSWORD);
 
 /****************************** Feeds ***************************************/
 
@@ -78,14 +74,6 @@ void loop() {
   // function definition further below.
   MQTT_connect();
 
-  // Try to ping the MQTT server
-  /*
-  if (! mqtt.ping(3) ) {
-    // MQTT pings failed, lets reconnect
-    Console.println("Ping fail!");
-  }
-  */
-
   // this is our 'wait for incoming subscription packets' busy subloop
   Adafruit_MQTT_Subscribe *subscription;
   while ((subscription = mqtt.readSubscription(1000))) {
@@ -105,7 +93,13 @@ void loop() {
     Console.println(F("OK!"));
   }
 
+  // ping the server to keep the mqtt connection alive
+  if(! mqtt.ping()) {
+    Serial.println(F("MQTT Ping failed."));
+  }
+
   delay(1000);
+
 }
 
 // Function to connect and reconnect as necessary to the MQTT server.