add /get MQTT publish method to trigger feed data resending

Author: abachman

src/AdafruitIO_Feed.cpp

@@ -31,12 +31,18 @@ AdafruitIO_Feed::~AdafruitIO_Feed()
   if(_pub)
     delete _pub;
 
+  if(_get_pub)
+    delete _pub;
+
   if(data)
     delete data;
 
   if(_topic)
     free(_topic);
 
+  if (_get_topic)
+    free(_get_topic);
+
   if(_feed_url)
     free(_feed_url);
 
@@ -103,6 +109,22 @@ bool AdafruitIO_Feed::save(double value, double lat, double lon, double ele, int
   return _pub->publish(data->toCSV());
 }
 
+bool AdafruitIO_Feed::get()
+{
+  if (!_get_topic)
+  {
+    _get_topic = (char *) malloc(sizeof(char) * (strlen(_io->_username) + strlen(name) + 12)); // 12 extra chars for /f/, /csv/get & null termination
+    strcpy(_get_topic, _io->_username);
+    strcat(_get_topic, "/f/");
+    strcat(_get_topic, name);
+    strcat(_get_topic, "/csv/get");
+
+    _get_pub = new Adafruit_MQTT_Publish(_io->_mqtt, _topic);
+  }
+
+  return _get_pub->publish('\0');
+}
+
 bool AdafruitIO_Feed::exists()
 {
   _io->_http->beginRequest();

src/AdafruitIO_Feed.h

@@ -37,6 +37,8 @@ class AdafruitIO_Feed : public AdafruitIO_MQTT {
     bool save(float value, double lat=0, double lon=0, double ele=0, int precision=6);
     bool save(double value, double lat=0, double lon=0, double ele=0, int precision=6);
 
+    bool get();
+
     bool exists();
     bool create();
 
@@ -56,11 +58,13 @@ class AdafruitIO_Feed : public AdafruitIO_MQTT {
     void _init();
 
     char *_topic;
+    char *_get_topic;
     char *_create_url;
     char *_feed_url;
 
     Adafruit_MQTT_Subscribe *_sub;
     Adafruit_MQTT_Publish *_pub;
+    Adafruit_MQTT_Publish *_get_pub;
 
     AdafruitIO *_io;
     AdafruitIO_Data *_data;