publish discovery once at each MQTT connection with retain flag set true (#507)

* publish discovery once at each MQTT connection with retain flag set to true

#448

main/ZgatewayBT.ino

@@ -1173,7 +1173,7 @@ void haRoomPresence(JsonObject &HomePresence)
   trc(F("BLE DISTANCE :"));
   trc(distance);
   String topic = String(Base_Topic) + "home_presence/" + String(gateway_name);
-  pub_custom_topic((char *)topic.c_str(), HomePresence);
+  pub_custom_topic((char *)topic.c_str(), HomePresence, false);
 }
 #endif
 

main/ZmqttDiscovery.ino

@@ -113,7 +113,7 @@ void createDiscovery(char *sensor_type,
     sensor.set("device", device); //device sensor is connected to
   }
   String topic = String(discovery_Topic) + "/" + String(sensor_type) + "/" + String(unique_id) + "/config";
-  pub_custom_topic((char *)topic.c_str(), sensor);
+  pub_custom_topic((char *)topic.c_str(), sensor, true);
 }
 
 void pubMqttDiscovery()
@@ -323,21 +323,6 @@ void pubMqttDiscovery()
                   0, "", "", true, "");
 #endif
 
-#ifdef ZgatewayRF315
-  // Sensor to display RF received value
-  trc(F("gatewayRF315Discovery"));
-  char *gatewayRF315[8] = {"sensor", "gatewayRF315", "", "", "{{ value_json.value }}", "", "", ""};
-  //component type,name,availability topic,device class,value template,payload on, payload off, unit of measurement
-
-  trc(F("CreateDiscoverySensor"));
-  trc(gatewayRF315[1]);
-  createDiscovery(gatewayRF315[0],
-                  subjectRF315toMQTT, gatewayRF315[1], (char *)getUniqueId(gatewayRF315[1], gatewayRF315[2]).c_str(),
-                  will_Topic, gatewayRF315[3], gatewayRF315[4],
-                  gatewayRF315[5], gatewayRF315[6], gatewayRF315[7],
-                  0, "", "", true, "");
-#endif
-
 #ifdef ZgatewayRFM69
   // Sensor to display RF received value
   trc(F("gatewayRFM69Discovery"));

main/main.ino

@@ -385,7 +385,7 @@ void pub(char *topicori, char *payload)
   }
 }
 
-void pub_custom_topic(char *topicori, JsonObject &data)
+void pub_custom_topic(char *topicori, JsonObject &data, boolean retain)
 {
   if (client.connected())
   {
@@ -394,7 +394,7 @@ void pub_custom_topic(char *topicori, JsonObject &data)
     trc(topicori);
     data.printTo(JSONmessageBuffer, sizeof(JSONmessageBuffer));
     trc(JSONmessageBuffer);
-    pubMQTT(topicori, JSONmessageBuffer);
+    pubMQTT(topicori, JSONmessageBuffer, retain);
   }
   else
   {
@@ -402,14 +402,20 @@ void pub_custom_topic(char *topicori, JsonObject &data)
   }
 }
 
-void pubMQTT(char *topic, char *payload)
+// Low level MQTT functions 
+void pubMQTT(char * topic, char * payload)
 {
-  client.publish(topic, payload);
+    client.publish(topic, payload);
 }
 
-void pubMQTT(String topic, char *payload)
+void pubMQTT(char * topicori, char * payload, bool retainFlag)
 {
-  client.publish((char *)topic.c_str(), payload);
+  client.publish(topicori, payload, retainFlag);
+}
+
+void pubMQTT(String topic, char *  payload)
+{
+    client.publish((char *)topic.c_str(),payload);
 }
 
 void pubMQTT(char *topic, unsigned long payload)
@@ -1085,6 +1091,10 @@ void loop()
       // MQTT loop
       connectedOnce = true;
       lastMQTTReconnectAttempt = 0;
+
+      #ifdef ZmqttDiscovery
+      if(!connectedOnce) pubMqttDiscovery(); // at first connection we publish the discovery payloads
+      #endif
       client.loop();
 
       #if defined(ESP8266) || defined(ESP32)