send status(battery..) as json

src/main.cpp

@@ -72,7 +72,7 @@ uint32_t lastTransmit = 0;
 //Variables for the mqtt packages and topics
 String commandTopic;
 String bme280Topic;
-String batteryTopic;
+String statusTopic;
 
 void setup() {
   // gpio configuration
@@ -90,7 +90,7 @@ void setup() {
   //Configure the MQTT topics
   commandTopic = "esp32-node/cmd/" + iot.hostname + "/play";
   bme280Topic = "esp32-node/stat/" + iot.hostname + "/bme280";
-  batteryTopic = "esp32-node/stat/" + iot.hostname + "/battery";
+  statusTopic = "esp32-node/stat/" + iot.hostname + "/status";
 
 /*
     //Use the web object to add elements to the interface
@@ -251,10 +251,15 @@ void transmitStatus() {
   uint16_t statusPacketIdSub;
   statusPacketIdSub = iot.mqtt.publish(bme280Topic.c_str(), 0, false, sensorBuf);
 //  statusPacketIdSub = iot.mqtt.publish(bme280Topic.c_str(), 1, true, sensorBuf);
-  int voltage = rom_phy_get_vdd33();
-  char batteryBuf[9];
-  sprintf(batteryBuf, "%d", voltage);
-  statusPacketIdSub = iot.mqtt.publish(batteryTopic.c_str(), 0, false, batteryBuf);
+
+  StaticJsonBuffer<200> jsonBuffer2;
+  JsonObject& root2 = jsonBuffer2.createObject();
+  root2["voltage"] = rom_phy_get_vdd33();
+  root2["rssi"] = WiFi.RSSI();
+  root2["heap"] = ESP.getFreeHeap();
+  char statusBuf[root2.measureLength()+1];
+  root2.printTo(sensorBuf, sizeof(sensorBuf));
+  statusPacketIdSub = iot.mqtt.publish(statusTopic.c_str(), 0, false, statusBuf);
 }