From a0520d3265814b34ccbbdd897f41f5fcee3d633e Mon Sep 17 00:00:00 2001
From: Todd Treece <toddtreece@gmail.com>
Date: Thu, 1 Oct 2015 12:00:56 -0400
Subject: [PATCH 01/29] default to MQTT_PROTOCOL_LEVEL 4

---
 Adafruit_MQTT.cpp | 6 +++---
 Adafruit_MQTT.h   | 6 ++++--
 2 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/Adafruit_MQTT.cpp b/Adafruit_MQTT.cpp
index 5558a65..5a9c5f2 100644
--- a/Adafruit_MQTT.cpp
+++ b/Adafruit_MQTT.cpp
@@ -119,13 +119,13 @@ 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;
@@ -143,7 +143,7 @@ int8_t Adafruit_MQTT::connect() {
     uint8_t len = subscribePacket(buffer, subscriptions[i]->topic, subscriptions[i]->qos);
     if (!sendPacket(buffer, len))
       return -1;
-    
+
     // Get SUBACK
     len = readPacket(buffer, 5, CONNECT_TIMEOUT_MS);
     DEBUG_PRINT(F("SUBACK:\t"));
diff --git a/Adafruit_MQTT.h b/Adafruit_MQTT.h
index e18110e..f093254 100644
--- a/Adafruit_MQTT.h
+++ b/Adafruit_MQTT.h
@@ -29,7 +29,7 @@
 #endif
 
 // Uncomment/comment to turn on/off debug output messages.
-//#define MQTT_DEBUG
+#define MQTT_DEBUG
 
 // Set where debug messages will be printed.
 #define DEBUG_PRINTER Serial
@@ -45,7 +45,9 @@
   #define DEBUG_PRINTBUFFER(buffer, len) {}
 #endif
 
-#define MQTT_PROTOCOL_LEVEL 3
+#ifndef MQTT_PROTOCOL_LEVEL
+  #define MQTT_PROTOCOL_LEVEL 4
+#endif
 
 #define MQTT_CTRL_CONNECT 0x01
 #define MQTT_CTRL_CONNECTACK 0x02

From ea779b1daaf26daa84e96e0a071d6cc2a9eb46c7 Mon Sep 17 00:00:00 2001
From: Todd Treece <toddtreece@gmail.com>
Date: Fri, 2 Oct 2015 10:43:11 -0400
Subject: [PATCH 02/29] allow user to define MQTT KEEPALIVE in sketch

---
 Adafruit_MQTT.h | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/Adafruit_MQTT.h b/Adafruit_MQTT.h
index f093254..b9a4c4a 100644
--- a/Adafruit_MQTT.h
+++ b/Adafruit_MQTT.h
@@ -65,7 +65,9 @@
 #define PING_TIMEOUT_MS 500
 
 // Adjust as necessary, in seconds.  Default to 5 minutes.
-#define MQTT_CONN_KEEPALIVE 300
+#ifndef MQTT_CONN_KEEPALIVE
+  #define MQTT_CONN_KEEPALIVE 300
+#endif
 
 // Largest full packet we're able to send.
 // Need to be able to store at least ~90 chars for a connect packet with full

From a3925bdb6ba42c287d5e60110a6938b4eda5adbd Mon Sep 17 00:00:00 2001
From: Todd Treece <toddtreece@gmail.com>
Date: Fri, 2 Oct 2015 10:45:00 -0400
Subject: [PATCH 03/29] adds MQTT 3.1.1 connect packet changes

---
 Adafruit_MQTT.cpp | 40 +++++++++++++++-------------------------
 1 file changed, 15 insertions(+), 25 deletions(-)

diff --git a/Adafruit_MQTT.cpp b/Adafruit_MQTT.cpp
index 5a9c5f2..261e464 100644
--- a/Adafruit_MQTT.cpp
+++ b/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)
@@ -96,25 +96,6 @@ Adafruit_MQTT::Adafruit_MQTT(const __FlashStringHelper *server, uint16_t port, c
   }
 }
 
-
-/*
-Adafruit_MQTT::Adafruit_MQTT(char *server, uint16_t port, char *cid, char *user, char *pass) {
-  strncpy(servername, server, SERVERNAME_SIZE);
-  servername[SERVERNAME_SIZE-1] = 0;
-  portnum = port;
-  serverip = 0;
-
-  strncpy(clientid, cid, CLIENTID_SIZE);
-  clientid[CLIENTID_SIZE-1] = 0;
-
-  strncpy(username, user, USERNAME_SIZE);
-  username[USERNAME_SIZE-1] = 0;
-
-  strncpy(password, pass, PASSWORD_SIZE);
-  password[PASSWORD_SIZE-1] = 0;
-}
-*/
-
 int8_t Adafruit_MQTT::connect() {
   // Connect to the server.
   if (!connectServer())
@@ -174,7 +155,7 @@ bool Adafruit_MQTT::publish(const char *topic, const char *data, uint8_t qos) {
   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);
@@ -262,11 +243,11 @@ bool Adafruit_MQTT::ping(uint8_t times) {
     uint8_t len = pingPacket(buffer);
     if (!sendPacket(buffer, len))
       return false;
-    
+
     // Process ping reply.
     len = readPacket(buffer, 2, PING_TIMEOUT_MS);
     if (buffer[0] == (MQTT_CTRL_PINGRESP << 4))
-      return true;  
+      return true;
   }
   return false;
 }
@@ -287,7 +268,10 @@ uint8_t Adafruit_MQTT::connectPacket(uint8_t *packet) {
   p+=2;
   // fill in packet[1] last
 
-  p = stringprint_P(p, PSTR("MQIsdp"));
+  if(MQTT_PROTOCOL_LEVEL == 3)
+    p = stringprint_P(p, PSTR("MQIsdp"));
+  else
+    p = stringprint_P(p, PSTR("MQTT"));
 
   p[0] = MQTT_PROTOCOL_LEVEL;
   p++;
@@ -305,7 +289,13 @@ uint8_t Adafruit_MQTT::connectPacket(uint8_t *packet) {
   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);
+    }
+  }
 
   if (pgm_read_byte(username) != 0) {
     p = stringprint_P(p, username);

From 913cce41af99e306f2fcaf25fcada5ca49e82c19 Mon Sep 17 00:00:00 2001
From: Todd Treece <toddtreece@gmail.com>
Date: Fri, 2 Oct 2015 17:10:16 -0400
Subject: [PATCH 04/29] adds zero byte client id option for 3.1.1

---
 Adafruit_MQTT.cpp | 6 ++++++
 Adafruit_MQTT.h   | 8 ++------
 2 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/Adafruit_MQTT.cpp b/Adafruit_MQTT.cpp
index 261e464..f038ec9 100644
--- a/Adafruit_MQTT.cpp
+++ b/Adafruit_MQTT.cpp
@@ -294,6 +294,12 @@ uint8_t Adafruit_MQTT::connectPacket(uint8_t *packet) {
   } 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"));
     }
   }
 
diff --git a/Adafruit_MQTT.h b/Adafruit_MQTT.h
index b9a4c4a..c0f68f1 100644
--- a/Adafruit_MQTT.h
+++ b/Adafruit_MQTT.h
@@ -45,9 +45,7 @@
   #define DEBUG_PRINTBUFFER(buffer, len) {}
 #endif
 
-#ifndef MQTT_PROTOCOL_LEVEL
-  #define MQTT_PROTOCOL_LEVEL 4
-#endif
+#define MQTT_PROTOCOL_LEVEL 4
 
 #define MQTT_CTRL_CONNECT 0x01
 #define MQTT_CTRL_CONNECTACK 0x02
@@ -65,9 +63,7 @@
 #define PING_TIMEOUT_MS 500
 
 // Adjust as necessary, in seconds.  Default to 5 minutes.
-#ifndef MQTT_CONN_KEEPALIVE
-  #define MQTT_CONN_KEEPALIVE 300
-#endif
+#define MQTT_CONN_KEEPALIVE 300
 
 // Largest full packet we're able to send.
 // Need to be able to store at least ~90 chars for a connect packet with full

From 4f3466bdbf505ac9918c33be98f41cf182ac9fe3 Mon Sep 17 00:00:00 2001
From: Todd Treece <toddtreece@gmail.com>
Date: Fri, 2 Oct 2015 17:13:35 -0400
Subject: [PATCH 05/29] comment out MQTT_DEBUG

---
 Adafruit_MQTT.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Adafruit_MQTT.h b/Adafruit_MQTT.h
index c0f68f1..34a39d6 100644
--- a/Adafruit_MQTT.h
+++ b/Adafruit_MQTT.h
@@ -29,7 +29,7 @@
 #endif
 
 // Uncomment/comment to turn on/off debug output messages.
-#define MQTT_DEBUG
+//#define MQTT_DEBUG
 
 // Set where debug messages will be printed.
 #define DEBUG_PRINTER Serial

From dfbe6a1e11e8e9cfb4b856a1c0b1d2a514b7863e Mon Sep 17 00:00:00 2001
From: Todd Treece <toddtreece@gmail.com>
Date: Fri, 2 Oct 2015 17:22:31 -0400
Subject: [PATCH 06/29] remove client id from esp example

---
 examples/mqtt_esp8266/mqtt_esp8266.ino | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/examples/mqtt_esp8266/mqtt_esp8266.ino b/examples/mqtt_esp8266/mqtt_esp8266.ino
index 8f06265..ca72c59 100644
--- a/examples/mqtt_esp8266/mqtt_esp8266.ino
+++ b/examples/mqtt_esp8266/mqtt_esp8266.ino
@@ -38,15 +38,11 @@ WiFiClient client;
 // Store the MQTT server, client ID, 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 ***************************************/
 

From 78d733aee359d4d93cf74af7d8a4e21709a59723 Mon Sep 17 00:00:00 2001
From: Todd Treece <toddtreece@gmail.com>
Date: Mon, 5 Oct 2015 09:14:17 -0400
Subject: [PATCH 07/29] define the missing MQTT control packets

---
 Adafruit_MQTT.h | 39 +++++++++++++++++++++++----------------
 1 file changed, 23 insertions(+), 16 deletions(-)

diff --git a/Adafruit_MQTT.h b/Adafruit_MQTT.h
index 34a39d6..32b7816 100644
--- a/Adafruit_MQTT.h
+++ b/Adafruit_MQTT.h
@@ -47,20 +47,27 @@
 
 #define MQTT_PROTOCOL_LEVEL 4
 
-#define MQTT_CTRL_CONNECT 0x01
-#define MQTT_CTRL_CONNECTACK 0x02
-#define MQTT_CTRL_PUBLISH 0x03
-#define MQTT_CTRL_SUBSCRIBE 0x08
-#define MQTT_CTRL_SUBACK 0x09
-#define MQTT_CTRL_PINGREQ 0x0C
-#define MQTT_CTRL_PINGRESP 0x0D
+#define MQTT_CTRL_CONNECT     0x1
+#define MQTT_CTRL_CONNECTACK  0x2
+#define MQTT_CTRL_PUBLISH     0x3
+#define MQTT_CTRL_PUBACK      0x4
+#define MQTT_CTRL_PUBREC      0x5
+#define MQTT_CTRL_PUBREL      0x6
+#define MQTT_CTRL_PUBCOMP     0x7
+#define MQTT_CTRL_SUBSCRIBE   0x8
+#define MQTT_CTRL_SUBACK      0x9
+#define MQTT_CTRL_UNSUBSCRIBE 0xA
+#define MQTT_CTRL_UNSUBSACK   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
@@ -70,15 +77,15 @@
 // 23 char client ID.
 #define MAXBUFFERSIZE (125)
 
-#define MQTT_CONN_USERNAMEFLAG 0x80
-#define MQTT_CONN_PASSWORDFLAG 0x40
-#define MQTT_CONN_WILLRETAIN   0x20
-#define MQTT_CONN_WILLQOS   0x08
-#define MQTT_CONN_WILLFLAG   0x04
-#define MQTT_CONN_CLEANSESSION   0x02
+#define MQTT_CONN_USERNAMEFLAG    0x80
+#define MQTT_CONN_PASSWORDFLAG    0x40
+#define MQTT_CONN_WILLRETAIN      0x20
+#define MQTT_CONN_WILLQOS_1       0x08
+#define MQTT_CONN_WILLQOS_2       0x18
+#define MQTT_CONN_WILLFLAG        0x04
+#define MQTT_CONN_CLEANSESSION    0x02
 
-// how many subscriptions we want to be able to
-// track
+// how many subscriptions we want to be able to track
 #define MAXSUBSCRIPTIONS 5
 
 // how much data we save in a subscription object

From b9a04c8be5873c94493efebe3814f3354eb3bea3 Mon Sep 17 00:00:00 2001
From: Todd Treece <toddtreece@gmail.com>
Date: Mon, 5 Oct 2015 09:25:07 -0400
Subject: [PATCH 08/29] adds will() method def

---
 Adafruit_MQTT.h | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/Adafruit_MQTT.h b/Adafruit_MQTT.h
index 32b7816..14940af 100644
--- a/Adafruit_MQTT.h
+++ b/Adafruit_MQTT.h
@@ -131,6 +131,14 @@ class Adafruit_MQTT {
   // 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

From b2a198af5a67feb85f9a354e880ba5f748e0b149 Mon Sep 17 00:00:00 2001
From: Todd Treece <toddtreece@gmail.com>
Date: Mon, 5 Oct 2015 09:26:06 -0400
Subject: [PATCH 09/29] adds unsubscribe() method def

---
 Adafruit_MQTT.h | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/Adafruit_MQTT.h b/Adafruit_MQTT.h
index 14940af..1fbd755 100644
--- a/Adafruit_MQTT.h
+++ b/Adafruit_MQTT.h
@@ -154,6 +154,9 @@ 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

From e60be3e972a9e54844e355007f47e96c47164689 Mon Sep 17 00:00:00 2001
From: Todd Treece <toddtreece@gmail.com>
Date: Mon, 5 Oct 2015 09:27:31 -0400
Subject: [PATCH 10/29] adds unsubscribePacket method def

---
 Adafruit_MQTT.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/Adafruit_MQTT.h b/Adafruit_MQTT.h
index 1fbd755..e567d47 100644
--- a/Adafruit_MQTT.h
+++ b/Adafruit_MQTT.h
@@ -198,6 +198,7 @@ class Adafruit_MQTT {
   uint8_t connectPacket(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);
 };
 

From e9e154ab52e45035df37fc445bae08492bf534aa Mon Sep 17 00:00:00 2001
From: Todd Treece <toddtreece@gmail.com>
Date: Mon, 5 Oct 2015 09:45:27 -0400
Subject: [PATCH 11/29] adds will support to the connect packet

---
 Adafruit_MQTT.cpp | 18 +++++++++++++++++-
 Adafruit_MQTT.h   |  4 ++++
 2 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/Adafruit_MQTT.cpp b/Adafruit_MQTT.cpp
index f038ec9..3f12f39 100644
--- a/Adafruit_MQTT.cpp
+++ b/Adafruit_MQTT.cpp
@@ -276,13 +276,29 @@ uint8_t Adafruit_MQTT::connectPacket(uint8_t *packet) {
   p[0] = MQTT_PROTOCOL_LEVEL;
   p++;
 
+  // always clean the session
   p[0] = MQTT_CONN_CLEANSESSION;
+
+  // set the will flags if needed
+  if (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++;
diff --git a/Adafruit_MQTT.h b/Adafruit_MQTT.h
index e567d47..29e4e70 100644
--- a/Adafruit_MQTT.h
+++ b/Adafruit_MQTT.h
@@ -189,6 +189,10 @@ 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
 
  private:

From 476d1115e67e1b7232adcac9cde05c9b6e5ccebe Mon Sep 17 00:00:00 2001
From: Todd Treece <toddtreece@gmail.com>
Date: Mon, 5 Oct 2015 09:50:57 -0400
Subject: [PATCH 12/29] adds will() function

---
 Adafruit_MQTT.cpp | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/Adafruit_MQTT.cpp b/Adafruit_MQTT.cpp
index 3f12f39..de046f0 100644
--- a/Adafruit_MQTT.cpp
+++ b/Adafruit_MQTT.cpp
@@ -167,6 +167,22 @@ 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

From 0fbd7346466ce3bab9400e7cba529b1420e4a617 Mon Sep 17 00:00:00 2001
From: Todd Treece <toddtreece@gmail.com>
Date: Mon, 5 Oct 2015 10:33:33 -0400
Subject: [PATCH 13/29] adds unsubscribe & unsubscribePacket functions

---
 Adafruit_MQTT.cpp | 69 +++++++++++++++++++++++++++++++++++++++++++++++
 Adafruit_MQTT.h   |  2 +-
 2 files changed, 70 insertions(+), 1 deletion(-)

diff --git a/Adafruit_MQTT.cpp b/Adafruit_MQTT.cpp
index de046f0..6d5a45a 100644
--- a/Adafruit_MQTT.cpp
+++ b/Adafruit_MQTT.cpp
@@ -206,6 +206,50 @@ 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) {
+
+        // 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;
 
@@ -396,6 +440,31 @@ 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 QoS > 1
+  // TODO: this shouldn't be a static value
+  p[0] = 0xAD;
+  p[1] = 0xAF;
+  p+=2;
+
+  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;
diff --git a/Adafruit_MQTT.h b/Adafruit_MQTT.h
index 29e4e70..ad5653d 100644
--- a/Adafruit_MQTT.h
+++ b/Adafruit_MQTT.h
@@ -57,7 +57,7 @@
 #define MQTT_CTRL_SUBSCRIBE   0x8
 #define MQTT_CTRL_SUBACK      0x9
 #define MQTT_CTRL_UNSUBSCRIBE 0xA
-#define MQTT_CTRL_UNSUBSACK   0xB
+#define MQTT_CTRL_UNSUBACK    0xB
 #define MQTT_CTRL_PINGREQ     0xC
 #define MQTT_CTRL_PINGRESP    0xD
 #define MQTT_CTRL_DISCONNECT  0xE

From 765a2feaffb26f6e12ee63bc50da7d075e1ec76e Mon Sep 17 00:00:00 2001
From: Todd Treece <toddtreece@gmail.com>
Date: Mon, 5 Oct 2015 10:38:09 -0400
Subject: [PATCH 14/29] remove broken while loop from ping()

---
 Adafruit_MQTT.cpp | 23 ++++++++++++-----------
 Adafruit_MQTT.h   |  5 ++---
 2 files changed, 14 insertions(+), 14 deletions(-)

diff --git a/Adafruit_MQTT.cpp b/Adafruit_MQTT.cpp
index 6d5a45a..7f4f587 100644
--- a/Adafruit_MQTT.cpp
+++ b/Adafruit_MQTT.cpp
@@ -297,19 +297,20 @@ Adafruit_MQTT_Subscribe *Adafruit_MQTT::readSubscription(int16_t timeout) {
   return subscriptions[i];
 }
 
-bool Adafruit_MQTT::ping(uint8_t times) {
-  while (times) {
-    // Construct and send ping packet.
-    uint8_t len = pingPacket(buffer);
-    if (!sendPacket(buffer, len))
-      return false;
+bool Adafruit_MQTT::ping() {
+
+  // Construct and send ping packet.
+  uint8_t len = pingPacket(buffer);
+  if (!sendPacket(buffer, len))
+    return false;
+
+  // Process ping reply.
+  len = readPacket(buffer, 2, PING_TIMEOUT_MS);
+  if (buffer[0] == (MQTT_CTRL_PINGRESP << 4))
+    return true;
 
-    // Process ping reply.
-    len = readPacket(buffer, 2, PING_TIMEOUT_MS);
-    if (buffer[0] == (MQTT_CTRL_PINGRESP << 4))
-      return true;
-  }
   return false;
+
 }
 
 // Packet Generation Functions /////////////////////////////////////////////////
diff --git a/Adafruit_MQTT.h b/Adafruit_MQTT.h
index ad5653d..5a9965d 100644
--- a/Adafruit_MQTT.h
+++ b/Adafruit_MQTT.h
@@ -163,9 +163,8 @@ class Adafruit_MQTT {
   // 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
-  // successful, otherwise false.
-  bool ping(uint8_t t);
+  // Ping the server to ensure the connection is still alive.
+  bool ping();
 
  protected:
   // Interface that subclasses need to implement:

From b9c9a288836c24937462afa371147474b5f50e78 Mon Sep 17 00:00:00 2001
From: Todd Treece <toddtreece@gmail.com>
Date: Mon, 5 Oct 2015 11:21:05 -0400
Subject: [PATCH 15/29] adds packet ids for publish QoS > 0

also adds packet id counter so packet ids aren't
static values. this is a step in the direction
of QoS 1 support
---
 Adafruit_MQTT.cpp | 31 +++++++++++++++++++++++--------
 Adafruit_MQTT.h   |  1 +
 2 files changed, 24 insertions(+), 8 deletions(-)

diff --git a/Adafruit_MQTT.cpp b/Adafruit_MQTT.cpp
index 7f4f587..d7e6fe1 100644
--- a/Adafruit_MQTT.cpp
+++ b/Adafruit_MQTT.cpp
@@ -225,7 +225,7 @@ bool Adafruit_MQTT::unsubscribe(Adafruit_MQTT_Subscribe *sub) {
 
       // if QoS for this subscription is 1 or 2, we need
       // to wait for the unsuback to confirm unsubscription
-      if(subscriptions[i]->qos > 0) {
+      if(subscriptions[i]->qos > 0 && MQTT_PROTOCOL_LEVEL > 3) {
 
         // wait for UNSUBACK
         len = readPacket(buffer, 5, CONNECT_TIMEOUT_MS);
@@ -404,6 +404,16 @@ 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));
@@ -424,11 +434,14 @@ uint8_t Adafruit_MQTT::subscribePacket(uint8_t *packet, const char *topic,
   // fill in packet[1] last
   p+=2;
 
-  // put in a message id,
-  p[0] = 0xAD;
-  p[1] = 0xAF;
+  // packet identifier. used for checking SUBACK
+  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);
 
   p[0] = qos;
@@ -450,12 +463,14 @@ uint8_t Adafruit_MQTT::unsubscribePacket(uint8_t *packet, const char *topic) {
   // fill in packet[1] last
   p+=2;
 
-  // packet identifier. used for QoS > 1
-  // TODO: this shouldn't be a static value
-  p[0] = 0xAD;
-  p[1] = 0xAF;
+  // 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;
diff --git a/Adafruit_MQTT.h b/Adafruit_MQTT.h
index 5a9965d..0ddf925 100644
--- a/Adafruit_MQTT.h
+++ b/Adafruit_MQTT.h
@@ -193,6 +193,7 @@ class Adafruit_MQTT {
   uint8_t will_qos;
   uint8_t will_retain;
   uint8_t buffer[MAXBUFFERSIZE];  // one buffer, used for all incoming/outgoing
+  uint16_t packet_id_counter = 0;
 
  private:
   Adafruit_MQTT_Subscribe *subscriptions[MAXSUBSCRIPTIONS];

From e70e2367b6383173f3a9d91b7062ad9610f36759 Mon Sep 17 00:00:00 2001
From: Todd Treece <toddtreece@gmail.com>
Date: Mon, 5 Oct 2015 11:32:10 -0400
Subject: [PATCH 16/29] only check for suback if using MQTT 3.1.1 or higher

---
 Adafruit_MQTT.cpp | 15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/Adafruit_MQTT.cpp b/Adafruit_MQTT.cpp
index d7e6fe1..302c47e 100644
--- a/Adafruit_MQTT.cpp
+++ b/Adafruit_MQTT.cpp
@@ -125,13 +125,16 @@ int8_t Adafruit_MQTT::connect() {
     if (!sendPacket(buffer, len))
       return -1;
 
-    // Get SUBACK
-    len = readPacket(buffer, 5, CONNECT_TIMEOUT_MS);
-    DEBUG_PRINT(F("SUBACK:\t"));
-    DEBUG_PRINTBUFFER(buffer, len);
-    if ((len != 5) || (buffer[0] != (MQTT_CTRL_SUBACK << 4))) {
-      return 6;  // failure to subscribe
+    // Check for SUBACK if using MQTT 3.1.1 or higher
+    if(MQTT_PROTOCOL_LEVEL > 3) {
+      len = readPacket(buffer, 5, CONNECT_TIMEOUT_MS);
+      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;

From 921c132f92f2879a0c9400d73293255d2a6d50c8 Mon Sep 17 00:00:00 2001
From: Todd Treece <toddtreece@gmail.com>
Date: Mon, 5 Oct 2015 13:41:14 -0400
Subject: [PATCH 17/29] adds missing will payload to connect packet

---
 Adafruit_MQTT.cpp | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/Adafruit_MQTT.cpp b/Adafruit_MQTT.cpp
index 302c47e..e738472 100644
--- a/Adafruit_MQTT.cpp
+++ b/Adafruit_MQTT.cpp
@@ -126,6 +126,8 @@ int8_t Adafruit_MQTT::connect() {
       return -1;
 
     // Check for SUBACK if using MQTT 3.1.1 or higher
+    // TODO: The Server is permitted to start sending PUBLISH packets matching the
+    // Subscription before the Server sends the SUBACK Packet.
     if(MQTT_PROTOCOL_LEVEL > 3) {
       len = readPacket(buffer, 5, CONNECT_TIMEOUT_MS);
       DEBUG_PRINT(F("SUBACK:\t"));
@@ -344,7 +346,7 @@ uint8_t Adafruit_MQTT::connectPacket(uint8_t *packet) {
   p[0] = MQTT_CONN_CLEANSESSION;
 
   // set the will flags if needed
-  if (pgm_read_byte(will_topic) != 0) {
+  if (will_topic && pgm_read_byte(will_topic) != 0) {
 
     p[0] |= MQTT_CONN_WILLFLAG;
 
@@ -383,6 +385,11 @@ uint8_t Adafruit_MQTT::connectPacket(uint8_t *packet) {
     }
   }
 
+  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);
   }

From f9ae6f31462fc61f1ca2d3d2571c9d6c899be6c8 Mon Sep 17 00:00:00 2001
From: Todd Treece <toddtreece@gmail.com>
Date: Mon, 5 Oct 2015 13:46:38 -0400
Subject: [PATCH 18/29] comment out suback for now

---
 Adafruit_MQTT.cpp | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/Adafruit_MQTT.cpp b/Adafruit_MQTT.cpp
index e738472..fc52516 100644
--- a/Adafruit_MQTT.cpp
+++ b/Adafruit_MQTT.cpp
@@ -128,14 +128,14 @@ int8_t Adafruit_MQTT::connect() {
     // Check for SUBACK if using MQTT 3.1.1 or higher
     // TODO: The Server is permitted to start sending PUBLISH packets matching the
     // Subscription before the Server sends the SUBACK Packet.
-    if(MQTT_PROTOCOL_LEVEL > 3) {
-      len = readPacket(buffer, 5, CONNECT_TIMEOUT_MS);
-      DEBUG_PRINT(F("SUBACK:\t"));
-      DEBUG_PRINTBUFFER(buffer, len);
-      if ((len != 5) || (buffer[0] != (MQTT_CTRL_SUBACK << 4))) {
-        return 6;  // failure to subscribe
-      }
-    }
+    // if(MQTT_PROTOCOL_LEVEL > 3) {
+    //   len = readPacket(buffer, 5, CONNECT_TIMEOUT_MS);
+    //   DEBUG_PRINT(F("SUBACK:\t"));
+    //   DEBUG_PRINTBUFFER(buffer, len);
+    //   if ((len != 5) || (buffer[0] != (MQTT_CTRL_SUBACK << 4))) {
+    //     return 6;  // failure to subscribe
+    //   }
+    // }
 
   }
 

From 16da46aece9a45bdcb2065eebe0deff33c415747 Mon Sep 17 00:00:00 2001
From: Todd Treece <toddtreece@gmail.com>
Date: Mon, 5 Oct 2015 14:07:49 -0400
Subject: [PATCH 19/29] renames disconnect to disconnectServer and adds
 disconnectPacket

---
 Adafruit_MQTT.cpp | 2 +-
 Adafruit_MQTT.h   | 9 ++++++---
 2 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/Adafruit_MQTT.cpp b/Adafruit_MQTT.cpp
index fc52516..66bd2fa 100644
--- a/Adafruit_MQTT.cpp
+++ b/Adafruit_MQTT.cpp
@@ -279,7 +279,7 @@ 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;
       }
     }
   }
diff --git a/Adafruit_MQTT.h b/Adafruit_MQTT.h
index 0ddf925..de05d50 100644
--- a/Adafruit_MQTT.h
+++ b/Adafruit_MQTT.h
@@ -124,9 +124,8 @@ 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
-  // otherwise.
-  virtual bool disconnect() = 0;  // Subclasses need to fill this in!
+  // Sends MQTT disconnect packet and calls disconnectServer()
+  bool disconnect();
 
   // Return true if connected to the MQTT server, otherwise false.
   virtual bool connected() = 0;  // Subclasses need to fill this in!
@@ -172,6 +171,9 @@ 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;
 
@@ -200,6 +202,7 @@ class Adafruit_MQTT {
 
   // 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);

From 4ab72be73e430439a71c87b8c9e19d675f85682f Mon Sep 17 00:00:00 2001
From: Todd Treece <toddtreece@gmail.com>
Date: Mon, 5 Oct 2015 14:18:31 -0400
Subject: [PATCH 20/29] adds disconnect & disconnectPacket functions

---
 Adafruit_MQTT.cpp | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/Adafruit_MQTT.cpp b/Adafruit_MQTT.cpp
index 66bd2fa..79a1ffe 100644
--- a/Adafruit_MQTT.cpp
+++ b/Adafruit_MQTT.cpp
@@ -155,6 +155,18 @@ 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);
@@ -499,6 +511,14 @@ 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 ////////////////////////////////////////////
 

From aa6db4d5f51e92ad38f2c8541e70e45cd33fe593 Mon Sep 17 00:00:00 2001
From: Todd Treece <toddtreece@gmail.com>
Date: Mon, 5 Oct 2015 14:18:49 -0400
Subject: [PATCH 21/29] rename all subclass diconnect() to disconnectServer()

---
 Adafruit_MQTT_CC3000.h   | 2 +-
 Adafruit_MQTT_Client.cpp | 2 +-
 Adafruit_MQTT_Client.h   | 2 +-
 Adafruit_MQTT_FONA.h     | 2 +-
 4 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/Adafruit_MQTT_CC3000.h b/Adafruit_MQTT_CC3000.h
index a1f6ea6..f064f0c 100644
--- a/Adafruit_MQTT_CC3000.h
+++ b/Adafruit_MQTT_CC3000.h
@@ -81,7 +81,7 @@ class Adafruit_MQTT_CC3000 : public Adafruit_MQTT {
     return mqttclient.connected();
   }
 
-  bool disconnect() {
+  bool disconnectServer() {
     if (connected()) {
       return (mqttclient.close() == 0);
     }
diff --git a/Adafruit_MQTT_Client.cpp b/Adafruit_MQTT_Client.cpp
index e0686d9..6612c8f 100644
--- a/Adafruit_MQTT_Client.cpp
+++ b/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()) {
diff --git a/Adafruit_MQTT_Client.h b/Adafruit_MQTT_Client.h
index e78c81b..416aef2 100644
--- a/Adafruit_MQTT_Client.h
+++ b/Adafruit_MQTT_Client.h
@@ -43,7 +43,7 @@ class Adafruit_MQTT_Client : public Adafruit_MQTT {
   {}
 
   bool connectServer();
-  bool disconnect();
+  bool disconnectServer();
   bool connected();
   uint16_t readPacket(uint8_t *buffer, uint8_t maxlen, int16_t timeout,
                       bool checkForValidPubPacket = false);
diff --git a/Adafruit_MQTT_FONA.h b/Adafruit_MQTT_FONA.h
index 17d73fe..204d10f 100644
--- a/Adafruit_MQTT_FONA.h
+++ b/Adafruit_MQTT_FONA.h
@@ -51,7 +51,7 @@ class Adafruit_MQTT_FONA : public Adafruit_MQTT {
     return fona->TCPconnect(server, portnum);
   }
 
-  bool disconnect() {
+  bool disconnectServer() {
     return fona->TCPclose();
   }
 

From b48265faedc40e3ac94a5d2f0563c8fe4ed14e58 Mon Sep 17 00:00:00 2001
From: Todd Treece <toddtreece@gmail.com>
Date: Mon, 5 Oct 2015 14:54:37 -0400
Subject: [PATCH 22/29] support anon auth & generated client id in constructor

---
 Adafruit_MQTT.cpp | 18 +++++++++++++-----
 Adafruit_MQTT.h   | 14 ++++++++++----
 2 files changed, 23 insertions(+), 9 deletions(-)

diff --git a/Adafruit_MQTT.cpp b/Adafruit_MQTT.cpp
index 79a1ffe..8c461dd 100644
--- a/Adafruit_MQTT.cpp
+++ b/Adafruit_MQTT.cpp
@@ -70,30 +70,39 @@ 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,
-                             const char *user, const char *pass) {
+Adafruit_MQTT::Adafruit_MQTT(const char *server, uint16_t port,
+                             const char *user, const char *pass,
+                             const char *cid) {
   servername = server;
   portnum = port;
   clientid = cid;
   username = user;
   password = pass;
 
+  // reset subscriptions
   for (uint8_t i=0; i<MAXSUBSCRIPTIONS; i++) {
     subscriptions[i] = 0;
   }
+
 }
 
-Adafruit_MQTT::Adafruit_MQTT(const __FlashStringHelper *server, uint16_t port, const __FlashStringHelper *cid,
-                             const __FlashStringHelper *user, const __FlashStringHelper *pass) {
+Adafruit_MQTT::Adafruit_MQTT(const __FlashStringHelper *server,
+                             uint16_t port,
+                             const __FlashStringHelper *user,
+                             const __FlashStringHelper *pass,
+                             const __FlashStringHelper *cid) {
+
   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;
   }
+
 }
 
 int8_t Adafruit_MQTT::connect() {
@@ -519,7 +528,6 @@ uint8_t Adafruit_MQTT::disconnectPacket(uint8_t *packet) {
   return 2;
 }
 
-
 // Adafruit_MQTT_Publish Definition ////////////////////////////////////////////
 
 Adafruit_MQTT_Publish::Adafruit_MQTT_Publish(Adafruit_MQTT *mqttserver, 
diff --git a/Adafruit_MQTT.h b/Adafruit_MQTT.h
index de05d50..fc65b0a 100644
--- a/Adafruit_MQTT.h
+++ b/Adafruit_MQTT.h
@@ -99,10 +99,16 @@ class Adafruit_MQTT_Subscribe;  // forward decl
 
 class Adafruit_MQTT {
  public:
-  Adafruit_MQTT(const char *server, uint16_t port, const char *cid,
-                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 = "io.adafruit.com",
+                uint16_t port = 1883, 
+                const char *user = "",
+                const char *pass = "",
+                const char *cid = "");
+  Adafruit_MQTT(const __FlashStringHelper *server = 0,
+                uint16_t port = 1883,
+                const __FlashStringHelper *user = 0,
+                const __FlashStringHelper *pass = 0,
+                const __FlashStringHelper *cid = 0);
   virtual ~Adafruit_MQTT() {}
 
   // Connect to the MQTT server.  Returns 0 on success, otherwise an error code

From f1499b484a985d95f51557e49a9e9136608c45a0 Mon Sep 17 00:00:00 2001
From: Todd Treece <toddtreece@gmail.com>
Date: Mon, 5 Oct 2015 14:57:44 -0400
Subject: [PATCH 23/29] rearrange child classes to match new constructor

---
 Adafruit_MQTT_CC3000.h | 10 +++++++---
 Adafruit_MQTT_Client.h | 11 +++++++----
 Adafruit_MQTT_FONA.h   | 10 +++++++---
 3 files changed, 21 insertions(+), 10 deletions(-)

diff --git a/Adafruit_MQTT_CC3000.h b/Adafruit_MQTT_CC3000.h
index f064f0c..e7e8eba 100644
--- a/Adafruit_MQTT_CC3000.h
+++ b/Adafruit_MQTT_CC3000.h
@@ -37,9 +37,13 @@
 // in the compilation of the library).
 class Adafruit_MQTT_CC3000 : public Adafruit_MQTT {
  public:
-  Adafruit_MQTT_CC3000(Adafruit_CC3000 *cc3k, const char *server, uint16_t port,
-                       const char *cid, const char *user, const char *pass):
-    Adafruit_MQTT(server, port, cid, user, pass),
+  Adafruit_MQTT_CC3000(Adafruit_CC3000 *cc3k,
+                       const char *server = "io.adafruit.com",
+                       uint16_t port = 1883,
+                       const char *user = "",
+                       const char *pass = "",
+                       const char *cid = ""):
+    Adafruit_MQTT(server, port, user, pass, cid),
     cc3000(cc3k)
   {}
 
diff --git a/Adafruit_MQTT_Client.h b/Adafruit_MQTT_Client.h
index 416aef2..20d704f 100644
--- a/Adafruit_MQTT_Client.h
+++ b/Adafruit_MQTT_Client.h
@@ -35,10 +35,13 @@
 // and even other platforms like ESP8266.
 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 *pass):
-    Adafruit_MQTT(server, port, cid, user, pass),
+  Adafruit_MQTT_Client(Client *client,
+                       const char *server = "io.adafruit.com",
+                       uint16_t port = 1883,
+                       const char *user = "",
+                       const char *pass = "",
+                       const char *cid = ""):
+    Adafruit_MQTT(server, port, user, pass, cid),
     client(client)
   {}
 
diff --git a/Adafruit_MQTT_FONA.h b/Adafruit_MQTT_FONA.h
index 204d10f..ec308f9 100644
--- a/Adafruit_MQTT_FONA.h
+++ b/Adafruit_MQTT_FONA.h
@@ -35,9 +35,13 @@
 // in the compilation of the library).
 class Adafruit_MQTT_FONA : public Adafruit_MQTT {
  public:
-  Adafruit_MQTT_FONA(Adafruit_FONA *f, const char *server, uint16_t port,
-                       const char *cid, const char *user, const char *pass):
-    Adafruit_MQTT(server, port, cid, user, pass),
+  Adafruit_MQTT_FONA(Adafruit_FONA *f,
+                       const char *server = "io.adafruit.com",
+                       uint16_t port = 1883,
+                       const char *user = "",
+                       const char *pass = "",
+                       const char *cid = ""):
+    Adafruit_MQTT(server, port, user, pass, cid),
     fona(f)
   {}
 

From 9a11d83cf51456699ea76604810f6e3bfac7c027 Mon Sep 17 00:00:00 2001
From: Todd Treece <toddtreece@gmail.com>
Date: Mon, 5 Oct 2015 15:26:02 -0400
Subject: [PATCH 24/29] removes client id from all example sketches

---
 Adafruit_MQTT.h                        | 2 +-
 examples/mqtt_cc3k/mqtt_cc3k.ino       | 8 ++------
 examples/mqtt_esp8266/mqtt_esp8266.ino | 4 ++--
 examples/mqtt_fona/mqtt_fona.ino       | 8 ++------
 examples/mqtt_yun/mqtt_yun.ino         | 8 ++------
 5 files changed, 9 insertions(+), 21 deletions(-)

diff --git a/Adafruit_MQTT.h b/Adafruit_MQTT.h
index fc65b0a..382dd87 100644
--- a/Adafruit_MQTT.h
+++ b/Adafruit_MQTT.h
@@ -100,7 +100,7 @@ class Adafruit_MQTT_Subscribe;  // forward decl
 class Adafruit_MQTT {
  public:
   Adafruit_MQTT(const char *server = "io.adafruit.com",
-                uint16_t port = 1883, 
+                uint16_t port = 1883,
                 const char *user = "",
                 const char *pass = "",
                 const char *cid = "");
diff --git a/examples/mqtt_cc3k/mqtt_cc3k.ino b/examples/mqtt_cc3k/mqtt_cc3k.ino
index bce77ed..4fa3a26 100644
--- a/examples/mqtt_cc3k/mqtt_cc3k.ino
+++ b/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);  }
diff --git a/examples/mqtt_esp8266/mqtt_esp8266.ino b/examples/mqtt_esp8266/mqtt_esp8266.ino
index ca72c59..75830c3 100644
--- a/examples/mqtt_esp8266/mqtt_esp8266.ino
+++ b/examples/mqtt_esp8266/mqtt_esp8266.ino
@@ -35,14 +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;
 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_USERNAME, MQTT_PASSWORD);
+Adafruit_MQTT_Client mqtt(&client, MQTT_SERVER, AIO_SERVERPORT, MQTT_USERNAME, MQTT_PASSWORD);
 
 /****************************** Feeds ***************************************/
 
diff --git a/examples/mqtt_fona/mqtt_fona.ino b/examples/mqtt_fona/mqtt_fona.ino
index 4af766a..45c41cb 100644
--- a/examples/mqtt_fona/mqtt_fona.ino
+++ b/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);  }
diff --git a/examples/mqtt_yun/mqtt_yun.ino b/examples/mqtt_yun/mqtt_yun.ino
index cea49d6..33fa550 100644
--- a/examples/mqtt_yun/mqtt_yun.ino
+++ b/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 ***************************************/
 

From 286245ab6252300061b9d553c482224539dd2b90 Mon Sep 17 00:00:00 2001
From: ladyada <limor@ladyada.net>
Date: Wed, 21 Oct 2015 00:05:46 -0400
Subject: [PATCH 25/29] compile fix & #ifdef the MQTT version

---
 Adafruit_MQTT.cpp | 9 +++++++--
 Adafruit_MQTT.h   | 2 +-
 2 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/Adafruit_MQTT.cpp b/Adafruit_MQTT.cpp
index 8c461dd..ae7b062 100644
--- a/Adafruit_MQTT.cpp
+++ b/Adafruit_MQTT.cpp
@@ -84,6 +84,7 @@ Adafruit_MQTT::Adafruit_MQTT(const char *server, uint16_t port,
     subscriptions[i] = 0;
   }
 
+  packet_id_counter = 0;
 }
 
 Adafruit_MQTT::Adafruit_MQTT(const __FlashStringHelper *server,
@@ -103,6 +104,7 @@ Adafruit_MQTT::Adafruit_MQTT(const __FlashStringHelper *server,
     subscriptions[i] = 0;
   }
 
+  packet_id_counter = 0;
 }
 
 int8_t Adafruit_MQTT::connect() {
@@ -355,10 +357,13 @@ uint8_t Adafruit_MQTT::connectPacket(uint8_t *packet) {
   p+=2;
   // fill in packet[1] last
 
-  if(MQTT_PROTOCOL_LEVEL == 3)
+#if MQTT_PROTOCOL_LEVEL == 3
     p = stringprint_P(p, PSTR("MQIsdp"));
-  else
+#elif MQTT_PROTOCOL_LEVEL == 4
     p = stringprint_P(p, PSTR("MQTT"));
+#else
+    #error "MQTT level not supported"
+#endif
 
   p[0] = MQTT_PROTOCOL_LEVEL;
   p++;
diff --git a/Adafruit_MQTT.h b/Adafruit_MQTT.h
index 382dd87..eaed311 100644
--- a/Adafruit_MQTT.h
+++ b/Adafruit_MQTT.h
@@ -201,7 +201,7 @@ class Adafruit_MQTT {
   uint8_t will_qos;
   uint8_t will_retain;
   uint8_t buffer[MAXBUFFERSIZE];  // one buffer, used for all incoming/outgoing
-  uint16_t packet_id_counter = 0;
+  uint16_t packet_id_counter;
 
  private:
   Adafruit_MQTT_Subscribe *subscriptions[MAXSUBSCRIPTIONS];

From 632c2f2cfe7a88291725f9fd2b8931d864a35367 Mon Sep 17 00:00:00 2001
From: ladyada <limor@ladyada.net>
Date: Wed, 21 Oct 2015 00:15:27 -0400
Subject: [PATCH 26/29] back compatible ping()

---
 Adafruit_MQTT.cpp | 25 +++++++++++++------------
 Adafruit_MQTT.h   |  2 +-
 2 files changed, 14 insertions(+), 13 deletions(-)

diff --git a/Adafruit_MQTT.cpp b/Adafruit_MQTT.cpp
index ae7b062..3721333 100644
--- a/Adafruit_MQTT.cpp
+++ b/Adafruit_MQTT.cpp
@@ -325,20 +325,21 @@ Adafruit_MQTT_Subscribe *Adafruit_MQTT::readSubscription(int16_t timeout) {
   return subscriptions[i];
 }
 
-bool Adafruit_MQTT::ping() {
-
-  // Construct and send ping packet.
-  uint8_t len = pingPacket(buffer);
-  if (!sendPacket(buffer, len))
-    return false;
-
-  // Process ping reply.
-  len = readPacket(buffer, 2, PING_TIMEOUT_MS);
-  if (buffer[0] == (MQTT_CTRL_PINGRESP << 4))
-    return true;
+bool Adafruit_MQTT::ping(uint8_t num = 1) {
 
+  while (num--) {
+    // Construct and send ping packet.
+    uint8_t len = pingPacket(buffer);
+    if (!sendPacket(buffer, len))
+      return false;
+    
+    // Process ping reply.
+    len = readPacket(buffer, 2, PING_TIMEOUT_MS);
+    if (buffer[0] == (MQTT_CTRL_PINGRESP << 4))
+      return true;
+  }
+    
   return false;
-
 }
 
 // Packet Generation Functions /////////////////////////////////////////////////
diff --git a/Adafruit_MQTT.h b/Adafruit_MQTT.h
index eaed311..e88735a 100644
--- a/Adafruit_MQTT.h
+++ b/Adafruit_MQTT.h
@@ -169,7 +169,7 @@ class Adafruit_MQTT {
   Adafruit_MQTT_Subscribe *readSubscription(int16_t timeout=0);
 
   // Ping the server to ensure the connection is still alive.
-  bool ping();
+  bool ping(uint8_t n);
 
  protected:
   // Interface that subclasses need to implement:

From 2aed9ae73764c5b5f1369ba6fee4db484326c18a Mon Sep 17 00:00:00 2001
From: Todd Treece <toddtreece@gmail.com>
Date: Thu, 22 Oct 2015 10:09:16 -0400
Subject: [PATCH 27/29] remove defaults from mqtt constructors

---
 Adafruit_MQTT.cpp      | 53 ++++++++++++++++++++++++++++++++++++++----
 Adafruit_MQTT.h        | 28 ++++++++++++++--------
 Adafruit_MQTT_CC3000.h | 16 +++++++------
 Adafruit_MQTT_Client.h | 16 +++++++------
 Adafruit_MQTT_FONA.h   | 16 +++++++------
 5 files changed, 93 insertions(+), 36 deletions(-)

diff --git a/Adafruit_MQTT.cpp b/Adafruit_MQTT.cpp
index 3721333..094af2a 100644
--- a/Adafruit_MQTT.cpp
+++ b/Adafruit_MQTT.cpp
@@ -70,9 +70,11 @@ 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 *user, const char *pass,
-                             const char *cid) {
+Adafruit_MQTT::Adafruit_MQTT(const char *server,
+                             uint16_t port,
+                             const char *cid,
+                             const char *user,
+                             const char *pass) {
   servername = server;
   portnum = port;
   clientid = cid;
@@ -85,13 +87,14 @@ Adafruit_MQTT::Adafruit_MQTT(const char *server, uint16_t port,
   }
 
   packet_id_counter = 0;
+
 }
 
 Adafruit_MQTT::Adafruit_MQTT(const __FlashStringHelper *server,
                              uint16_t port,
+                             const __FlashStringHelper *cid,
                              const __FlashStringHelper *user,
-                             const __FlashStringHelper *pass,
-                             const __FlashStringHelper *cid) {
+                             const __FlashStringHelper *pass) {
 
   servername = (const char *)server;
   portnum = port;
@@ -105,6 +108,46 @@ Adafruit_MQTT::Adafruit_MQTT(const __FlashStringHelper *server,
   }
 
   packet_id_counter = 0;
+
+}
+
+Adafruit_MQTT::Adafruit_MQTT(const char *server,
+                             uint16_t port,
+                             const char *user,
+                             const char *pass) {
+  servername = server;
+  portnum = port;
+  clientid = "";
+  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 *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;
+
 }
 
 int8_t Adafruit_MQTT::connect() {
diff --git a/Adafruit_MQTT.h b/Adafruit_MQTT.h
index f2fee07..2b9341a 100644
--- a/Adafruit_MQTT.h
+++ b/Adafruit_MQTT.h
@@ -100,16 +100,24 @@ class Adafruit_MQTT_Subscribe;  // forward decl
 
 class Adafruit_MQTT {
  public:
-  Adafruit_MQTT(const char *server = "io.adafruit.com",
-                uint16_t port = 1883,
-                const char *user = "",
-                const char *pass = "",
-                const char *cid = "");
-  Adafruit_MQTT(const __FlashStringHelper *server = 0,
-                uint16_t port = 1883,
-                const __FlashStringHelper *user = 0,
-                const __FlashStringHelper *pass = 0,
-                const __FlashStringHelper *cid = 0);
+  Adafruit_MQTT(const char *server,
+                uint16_t port,
+                const char *cid,
+                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
diff --git a/Adafruit_MQTT_CC3000.h b/Adafruit_MQTT_CC3000.h
index e7e8eba..277a0fb 100644
--- a/Adafruit_MQTT_CC3000.h
+++ b/Adafruit_MQTT_CC3000.h
@@ -37,13 +37,15 @@
 // in the compilation of the library).
 class Adafruit_MQTT_CC3000 : public Adafruit_MQTT {
  public:
-  Adafruit_MQTT_CC3000(Adafruit_CC3000 *cc3k,
-                       const char *server = "io.adafruit.com",
-                       uint16_t port = 1883,
-                       const char *user = "",
-                       const char *pass = "",
-                       const char *cid = ""):
-    Adafruit_MQTT(server, port, user, pass, cid),
+  Adafruit_MQTT_CC3000(Adafruit_CC3000 *cc3k, const char *server, uint16_t port,
+                       const char *cid, const char *user, const char *pass):
+    Adafruit_MQTT(server, port, cid, user, pass),
+    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)
   {}
 
diff --git a/Adafruit_MQTT_Client.h b/Adafruit_MQTT_Client.h
index 20d704f..c9b4366 100644
--- a/Adafruit_MQTT_Client.h
+++ b/Adafruit_MQTT_Client.h
@@ -35,13 +35,15 @@
 // and even other platforms like ESP8266.
 class Adafruit_MQTT_Client : public Adafruit_MQTT {
  public:
-  Adafruit_MQTT_Client(Client *client,
-                       const char *server = "io.adafruit.com",
-                       uint16_t port = 1883,
-                       const char *user = "",
-                       const char *pass = "",
-                       const char *cid = ""):
-    Adafruit_MQTT(server, port, user, pass, cid),
+  Adafruit_MQTT_Client(Client *client, const char *server, uint16_t port,
+                       const char *cid, const char *user, 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)
   {}
 
diff --git a/Adafruit_MQTT_FONA.h b/Adafruit_MQTT_FONA.h
index ec308f9..a65b99d 100644
--- a/Adafruit_MQTT_FONA.h
+++ b/Adafruit_MQTT_FONA.h
@@ -35,13 +35,15 @@
 // in the compilation of the library).
 class Adafruit_MQTT_FONA : public Adafruit_MQTT {
  public:
-  Adafruit_MQTT_FONA(Adafruit_FONA *f,
-                       const char *server = "io.adafruit.com",
-                       uint16_t port = 1883,
-                       const char *user = "",
-                       const char *pass = "",
-                       const char *cid = ""):
-    Adafruit_MQTT(server, port, user, pass, cid),
+  Adafruit_MQTT_FONA(Adafruit_FONA *f, const char *server, uint16_t port,
+                       const char *cid, const char *user, const char *pass):
+    Adafruit_MQTT(server, port, cid, user, pass),
+    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)
   {}
 

From 7c2b558ee942e22961fbd85ffa26bb8a9beb8052 Mon Sep 17 00:00:00 2001
From: ladyada <limor@ladyada.net>
Date: Thu, 22 Oct 2015 13:03:55 -0400
Subject: [PATCH 28/29] ping flushes input, tries multiple times

---
 Adafruit_MQTT.cpp | 11 +++++++++--
 Adafruit_MQTT.h   |  4 +++-
 2 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/Adafruit_MQTT.cpp b/Adafruit_MQTT.cpp
index 094af2a..7a87f16 100644
--- a/Adafruit_MQTT.cpp
+++ b/Adafruit_MQTT.cpp
@@ -368,13 +368,20 @@ Adafruit_MQTT_Subscribe *Adafruit_MQTT::readSubscription(int16_t timeout) {
   return subscriptions[i];
 }
 
-bool Adafruit_MQTT::ping(uint8_t num = 1) {
+void Adafruit_MQTT::flushIncoming(uint16_t timeout) {
+  // 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);
diff --git a/Adafruit_MQTT.h b/Adafruit_MQTT.h
index 2b9341a..7bba0a4 100644
--- a/Adafruit_MQTT.h
+++ b/Adafruit_MQTT.h
@@ -178,7 +178,7 @@ class Adafruit_MQTT {
   Adafruit_MQTT_Subscribe *readSubscription(int16_t timeout=0);
 
   // Ping the server to ensure the connection is still alive.
-  bool ping(uint8_t n);
+  bool ping(uint8_t n = 1);
 
  protected:
   // Interface that subclasses need to implement:
@@ -215,6 +215,8 @@ class Adafruit_MQTT {
  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);

From 4dc6f1e486cd02984a93e3d367d952ccb2d601ef Mon Sep 17 00:00:00 2001
From: Todd Treece <toddtreece@gmail.com>
Date: Thu, 22 Oct 2015 14:13:19 -0400
Subject: [PATCH 29/29] adds ping to the end of the main loop in examples

---
 examples/mqtt_cc3k/mqtt_cc3k.ino         | 16 +++----
 examples/mqtt_esp8266/mqtt_esp8266.ino   | 14 +++---
 examples/mqtt_ethernet/mqtt_ethernet.ino | 13 +++---
 examples/mqtt_fona/mqtt_fona.ino         | 55 +++++++++++++-----------
 examples/mqtt_yun/mqtt_yun.ino           | 14 +++---
 5 files changed, 55 insertions(+), 57 deletions(-)

diff --git a/examples/mqtt_cc3k/mqtt_cc3k.ino b/examples/mqtt_cc3k/mqtt_cc3k.ino
index 4fa3a26..c7db7ee 100644
--- a/examples/mqtt_cc3k/mqtt_cc3k.ino
+++ b/examples/mqtt_cc3k/mqtt_cc3k.ino
@@ -104,16 +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;
@@ -133,6 +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.
diff --git a/examples/mqtt_esp8266/mqtt_esp8266.ino b/examples/mqtt_esp8266/mqtt_esp8266.ino
index 75830c3..8defec1 100644
--- a/examples/mqtt_esp8266/mqtt_esp8266.ino
+++ b/examples/mqtt_esp8266/mqtt_esp8266.ino
@@ -90,14 +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))) {
@@ -117,7 +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.
diff --git a/examples/mqtt_ethernet/mqtt_ethernet.ino b/examples/mqtt_ethernet/mqtt_ethernet.ino
index c27f8a8..ecb1a24 100644
--- a/examples/mqtt_ethernet/mqtt_ethernet.ino
+++ b/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.
diff --git a/examples/mqtt_fona/mqtt_fona.ino b/examples/mqtt_fona/mqtt_fona.ino
index 45c41cb..a7b00aa 100644
--- a/examples/mqtt_fona/mqtt_fona.ino
+++ b/examples/mqtt_fona/mqtt_fona.ino
@@ -113,30 +113,10 @@ void loop() {
   // Make sure to reset watchdog every loop iteration!
   Watchdog.reset();
 
-  // check if we're still connected
-  if (!fona.TCPconnected() || (txfailures >= MAXTXFAILURES)) {
-    Serial.println(F("Connecting to MQTT..."));
-    int8_t ret, retries = 5;
-    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!");
-  }
-  */
-
+  // Ensure the connection to the MQTT server is alive (this will make the first
+  // connection and automatically reconnect when disconnected).  See the MQTT_connect
+  // function definition further below.
+  MQTT_connect();
 
   // this is our 'wait for incoming subscription packets' busy subloop
   Adafruit_MQTT_Subscribe *subscription;
@@ -158,4 +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!");
 }
diff --git a/examples/mqtt_yun/mqtt_yun.ino b/examples/mqtt_yun/mqtt_yun.ino
index 33fa550..b02d06d 100644
--- a/examples/mqtt_yun/mqtt_yun.ino
+++ b/examples/mqtt_yun/mqtt_yun.ino
@@ -74,14 +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))) {
@@ -101,7 +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.