[DISC] Add ability to change Discovery Prefix via WebUI or via mosquitto_pub (#2007)

Add discovery_prefix change at runtime

---------

Co-authored-by: Florian <1technophile@users.noreply.github.com>

docs/use/gateway.md

@@ -85,11 +85,12 @@ build_flags = '-UMQTTsetMQTT'
 If the new connection fails the gateway will fallback to the previous connection.
 :::
 
-## Change the MQTT main topic and or gateway name
+## Change the MQTT main topic, discovery prefix, and or gateway name
 ```
 mosquitto_pub -t "home/OpenMQTTGateway/commands/MQTTtoSYS/config" -m
 '{
   "mqtt_topic": "topic/",
+  "discovery_prefix": "prefix",
   "gateway_name": "name"
 }'
 ```

main/ZmqttDiscovery.ino

@@ -187,7 +187,7 @@ void announceDeviceTrigger(bool use_gateway_info, char* topic, char* type, char*
   sensor["device"] = device; //device representing the board
 
   /* Publish on the topic */
-  String topic_to_publish = String(discovery_Topic) + "/device_automation/" + String(unique_id) + "/config";
+  String topic_to_publish = String(discovery_prefix) + "/device_automation/" + String(unique_id) + "/config";
   Log.trace(F("Announce Device Trigger  %s" CR), topic_to_publish.c_str());
   pub_custom_topic((char*)topic_to_publish.c_str(), sensor, true);
 }
@@ -434,7 +434,7 @@ void createDiscovery(const char* sensor_type,
 
   sensor["device"] = device;
 
-  String topic = String(discovery_Topic) + "/" + String(sensor_type) + "/" + String(unique_id) + "/config";
+  String topic = String(discovery_prefix) + "/" + String(sensor_type) + "/" + String(unique_id) + "/config";
   Log.trace(F("Announce Device %s on  %s" CR), String(sensor_type).c_str(), topic.c_str());
   pub_custom_topic((char*)topic.c_str(), sensor, true);
 }
@@ -443,7 +443,7 @@ void eraseTopic(const char* sensor_type, const char* unique_id) {
   if (sensor_type == NULL || unique_id == NULL) {
     return;
   }
-  String topic = String(discovery_Topic) + "/" + String(sensor_type) + "/" + String(unique_id) + "/config";
+  String topic = String(discovery_prefix) + "/" + String(sensor_type) + "/" + String(unique_id) + "/config";
   Log.trace(F("Erase entity discovery %s on  %s" CR), String(sensor_type).c_str(), topic.c_str());
   pubMQTT((char*)topic.c_str(), "", true);
 }

main/ZwebUI.ino

@@ -692,7 +692,8 @@ void handleWI() {
  * T: handleMQ Arg: 4, sc=on
  * T: handleMQ Arg: 5, h=
  * T: handleMQ Arg: 6, mt=home/
- * T: handleMQ Arg: 7, save=
+ * T: handleMQ Arg: 7 dp=homeassistant (#ifdef ZmqttDiscovery)
+ * T: handleMQ Arg: 8, save=
  */
 void handleMQ() {
   WEBUI_TRACE_LOG(F("handleMQ: uri: %s, args: %d, method: %d" CR), server.uri(), server.args(), server.method());
@@ -762,6 +763,14 @@ void handleMQ() {
           update = true;
         }
       }
+#  ifdef ZmqttDiscovery
+      if (server.hasArg("dp")) {
+        WEBtoSYS["discovery_prefix"] = server.arg("dp");
+        if (strncmp(discovery_prefix, server.arg("dp").c_str(), parameters_size)) {
+          update = true;
+        }
+      }
+#  endif
 
 #  ifndef ESPWifiManualSetup
       if (update) {
@@ -803,11 +812,19 @@ void handleMQ() {
   String response = String(buffer);
   response += String(script);
   response += String(style);
-  // mqtt server (mh), mqtt port (ml), mqtt username (mu), mqtt password (mp), secure connection (sc), server certificate (msc), topic (mt)
+  // mqtt server (mh), mqtt port (ml), mqtt username (mu), mqtt password (mp), secure connection (sc), server certificate (msc), mqtt topic (mt), discovery prefix (dp) (last one only #ifdef ZmqttDiscovery)
 #  if MQTT_BROKER_MODE
+#    ifdef ZmqttDiscovery
+  snprintf(buffer, WEB_TEMPLATE_BUFFER_MAX_SIZE, config_mqtt_body, jsonChar, gateway_name, "", "1883", "", "", gateway_name, mqtt_topic, discovery_prefix);
+#    else
   snprintf(buffer, WEB_TEMPLATE_BUFFER_MAX_SIZE, config_mqtt_body, jsonChar, gateway_name, "", "1883", "", "", gateway_name, mqtt_topic);
+#    endif
 #  else
+#    ifdef ZmqttDiscovery
+  snprintf(buffer, WEB_TEMPLATE_BUFFER_MAX_SIZE, config_mqtt_body, jsonChar, gateway_name, cnt_parameters_array[CNT_DEFAULT_INDEX].mqtt_server, cnt_parameters_array[CNT_DEFAULT_INDEX].mqtt_port, cnt_parameters_array[CNT_DEFAULT_INDEX].mqtt_user, (cnt_parameters_array[CNT_DEFAULT_INDEX].isConnectionSecure ? "checked" : ""), gateway_name, mqtt_topic, discovery_prefix);
+#    else
   snprintf(buffer, WEB_TEMPLATE_BUFFER_MAX_SIZE, config_mqtt_body, jsonChar, gateway_name, cnt_parameters_array[CNT_DEFAULT_INDEX].mqtt_server, cnt_parameters_array[CNT_DEFAULT_INDEX].mqtt_port, cnt_parameters_array[CNT_DEFAULT_INDEX].mqtt_user, (cnt_parameters_array[CNT_DEFAULT_INDEX].isConnectionSecure ? "checked" : ""), gateway_name, mqtt_topic);
+#    endif
 #  endif
   response += String(buffer);
   snprintf(buffer, WEB_TEMPLATE_BUFFER_MAX_SIZE, footer, OMG_VERSION);

main/config_WebContent.h

@@ -100,11 +100,13 @@ const char information_body[] = body_header "<style>td {padding: 0px 5px;}</styl
 const char upgrade_body[] = body_header "<div id='f1' style='display:block;'><fieldset class=\"set1\"><legend><span><b>Upgrade by Web Server</b></span></legend><form method='get' action='up'><br><b>OTA URL</b><br><input id='o' placeholder=\"OTA_URL\" value=\"%s\"><br><br><button type='submit' class='button bgrn'>Start upgrade</button></form></fieldset><br><br><fieldset class=\"set1\"><legend><span><b>Upgrade to Level</b></span></legend><form method='get' action='up'><p><b>Level</b><br><select id='le'><option value='1'>Latest Release</option><option value='2'>Development</option></select></p><br><button type='submit' class='button bgrn'>Start upgrade</button></form></fieldset></div><div id='f2' style='display:none;text-align:center;'><b>Upload started ...</b></div><div id=but2d style=\"display: block;\"></div><p>" body_footer_main_menu;
 
 const char config_wifi_body[] = body_header "%s<br><div><a href='/wi?scan='><b>Scan for all WiFi Networks</b></a></div><br><fieldset class=\"set1\"><legend><span><b>WiFi Parameters</b></span></legend><form method='get' action='wi'><p><b>WiFi Network</b> () <br><input id='s1' placeholder=\"Type or Select your WiFi Network\" value=\"%s\"></p><p><label><b>WiFi Password</b></label><br><input id='p1' type='password' placeholder=\"Enter your WiFi Password\" ></p><br><button name='save' type='submit' class='button bgrn'>Save</button></form></fieldset>" body_footer_config_menu;
-
-// mqtt server (mh), mqtt port (ml), mqtt username (mu), mqtt password (mp), secure connection (sc), server certificate (msc), topic (mt)
-
+#ifdef ZmqttDiscovery
+// mqtt server (mh), mqtt port (ml), mqtt username (mu), mqtt password (mp), secure connection (sc), server certificate (msc), mqtt topic (mt), discovery prefix (dp)
+const char config_mqtt_body[] = body_header "<fieldset class=\"set1\"><legend><span><b>MQTT Parameters</b></span></legend><form method='get' action='mq'><p><b>MQTT Server</b><br><input id='mh' placeholder=" MQTT_SERVER " value='%s'></p><p><b>MQTT Port</b><br><input id='ml' placeholder=" MQTT_PORT " value='%s'></p><p><b>MQTT Username</b><br><input id='mu' placeholder=" MQTT_USER " value='%s'></p><p><label><b>MQTT Password</b></label><br><input id='mp' type='password' placeholder=\"Password\" ></p><p><b>MQTT Secure Connection</b><br><input id='sc' type='checkbox' %s></p><p><b>Gateway Name</b><br><input id='h' placeholder=" Gateway_Name " value=\"%s\"></p><p><b>MQTT Base Topic</b><br><input id='mt' placeholder='' value='%s'></p><p><b>MQTT Discovery Prefix</b><br><input id='dp' placeholder='' value='%s'></p><br><button name='save' type='submit' class='button bgrn'>Save</button></form></fieldset>" body_footer_config_menu;
+#else
+// mqtt server (mh), mqtt port (ml), mqtt username (mu), mqtt password (mp), secure connection (sc), server certificate (msc), mqtt topic (mt)
 const char config_mqtt_body[] = body_header "<fieldset class=\"set1\"><legend><span><b>MQTT Parameters</b></span></legend><form method='get' action='mq'><p><b>MQTT Server</b><br><input id='mh' placeholder=" MQTT_SERVER " value='%s'></p><p><b>MQTT Port</b><br><input id='ml' placeholder=" MQTT_PORT " value='%s'></p><p><b>MQTT Username</b><br><input id='mu' placeholder=" MQTT_USER " value='%s'></p><p><label><b>MQTT Password</b></label><br><input id='mp' type='password' placeholder=\"Password\" ></p><p><b>MQTT Secure Connection</b><br><input id='sc' type='checkbox' %s></p><p><b>Gateway Name</b><br><input id='h' placeholder=" Gateway_Name " value=\"%s\"></p><p><b>MQTT Base Topic</b><br><input id='mt' placeholder='' value='%s'></p><br><button name='save' type='submit' class='button bgrn'>Save</button></form></fieldset>" body_footer_config_menu;
-
+#endif
 #ifndef ESPWifiManualSetup
 const char config_gateway_body[] = body_header "<fieldset class=\"set1\"><legend><span><b>Gateway Configuration</b></span></legend><form method='get' action='cg'><p><b>Gateway Password (8 characters min)</b><br><input id='gp' type='password' placeholder=\"********\"  minlength='8'></p><br><button name='save' type='submit' class='button bgrn'>Save</button></form></fieldset>" body_footer_config_menu;
 #endif
@@ -321,4 +323,4 @@ const unsigned char Openmqttgateway_logo_mini_ico[] = {
     0x00, 0x00, 0xff, 0x07, 0x00, 0x00, 0xff, 0x07, 0x00, 0x00};
 unsigned int Openmqttgateway_logo_mini_ico_len = 1150;
 
-#endif
+#endif

main/config_mqttDiscovery.h

@@ -112,9 +112,14 @@ void announceDeviceTrigger(bool use_gateway_info,
                            char* device_model,
                            char* device_mac);
 
-#ifndef discovery_Topic
-#  define discovery_Topic "homeassistant"
+#ifdef discovery_Topic //Deprecated - use discovery_Prefix instead
+#  define discovery_Prefix "homeassistant"
 #endif
+#ifndef discovery_Prefix
+#  define discovery_Prefix "homeassistant"
+#endif
+char discovery_prefix[parameters_size + 1] = discovery_Prefix;
+
 // discovery_republish_on_reconnect false to publish discovery topics over MQTT only with first connect
 // discovery_republish_on_reconnect true to always republish discovery topics over MQTT when connection is re-established
 #ifndef discovery_republish_on_reconnect

main/main.ino

@@ -340,7 +340,7 @@ protected:
     // Whenever a client subscribes successfully to some topic, see if this is likely a subscription to a
     // autodiscovery topic.  If it is, fire handle_autodiscovery().
     const String pattern(topic);
-    const bool is_autodiscovery_subscription = (pattern == "#") || (pattern.startsWith(String(discovery_Topic) + "/"));
+    const bool is_autodiscovery_subscription = (pattern == "#") || (pattern.startsWith(String(discovery_prefix) + "/"));
     if (is_autodiscovery_subscription)
       handle_autodiscovery();
   }
@@ -1333,6 +1333,9 @@ void setup() {
   Log.trace(F("OpenMQTTGateway ip: %s" CR), WiFi.localIP().toString().c_str());
   Log.trace(F("OpenMQTTGateway index %d" CR), cnt_index);
   Log.trace(F("OpenMQTTGateway mqtt topic: %s" CR), mqtt_topic);
+#ifdef ZmqttDiscovery
+  Log.trace(F("OpenMQTTGateway mqtt discovery prefix: %s" CR), discovery_prefix);
+#endif
   Log.trace(F("OpenMQTTGateway gateway name: %s" CR), gateway_name);
 #if !MQTT_BROKER_MODE
   Log.trace(F("OpenMQTTGateway mqtt server: %s" CR), cnt_parameters_array[cnt_index].mqtt_server);
@@ -1913,6 +1916,9 @@ void saveConfig() {
 #  endif
 
   json["mqtt_topic"] = mqtt_topic;
+#  ifdef ZmqttDiscovery
+  json["discovery_prefix"] = discovery_prefix;
+#  endif
   json["gateway_name"] = gateway_name;
   json["ota_pass"] = ota_pass;
 
@@ -2041,6 +2047,10 @@ bool loadConfigFromFlash() {
 #  endif
         if (json.containsKey("mqtt_topic"))
           strcpy(mqtt_topic, json["mqtt_topic"]);
+#  ifdef ZmqttDiscovery
+        if (json.containsKey("discovery_prefix"))
+          strcpy(discovery_prefix, json["discovery_prefix"]);
+#  endif
         if (json.containsKey("gateway_name"))
           strcpy(gateway_name, json["gateway_name"]);
         if (json.containsKey("ota_pass")) {
@@ -3280,11 +3290,20 @@ void MQTTtoSYS(char* topicOri, JsonObject& SYSdata) { // json object decoding
     }
 
     if ((SYSdata.containsKey("mqtt_topic") && SYSdata["mqtt_topic"].is<char*>()) ||
+#ifdef ZmqttDiscovery
+        (SYSdata.containsKey("discovery_prefix") && SYSdata["discovery_prefix"].is<char*>()) ||
+#endif
         (SYSdata.containsKey("gateway_name") && SYSdata["gateway_name"].is<char*>()) ||
         (SYSdata.containsKey("gw_pass") && SYSdata["gw_pass"].is<char*>())) {
       if (SYSdata.containsKey("mqtt_topic")) {
         strncpy(mqtt_topic, SYSdata["mqtt_topic"], parameters_size);
       }
+#ifdef ZmqttDiscovery
+      if (SYSdata.containsKey("discovery_prefix")) {
+        strncpy(discovery_prefix, SYSdata["discovery_prefix"], parameters_size);
+        restartESP = true; //Need to reset so all devices get re-discovered & published to new discovery_prefix
+      }
+#endif
       if (SYSdata.containsKey("gateway_name")) {
         strncpy(gateway_name, SYSdata["gateway_name"], parameters_size);
       }