Skip MQTT response if command is prefixed with underscore (#21740)

CHANGELOG.md

@@ -16,6 +16,8 @@ All notable changes to this project will be documented in this file.
 - Berry `int64` added `low32()` and `high32()` methods, used in Matter (#21728)
 - Matter support for 'Generic Switch' based on Tasmota Buttons (#21731)
 - Berry cam module and img class (#21743)
+- Skip MQTT response if command is prefixed with underscore (#21740)
+- Skip MQTT response if commands are executed prefixed with ``Backlog2`` (no delay) or ``Backlog3`` (#21740)
 
 ### Breaking Changed
 

RELEASENOTES.md

@@ -124,6 +124,8 @@ The latter links can be used for OTA upgrades too like ``OtaUrl https://ota.tasm
 - Support for QMP6988 temperature and pressure sensor
 - Support for Sonoff WTS01 temperature sensor using SerialBridge in ``SSerialMode 3``
 - Support for Sonoff POWCT Ring [#21131](https://github.com/arendst/Tasmota/issues/21131)
+- Skip MQTT response if command is prefixed with underscore [#21740](https://github.com/arendst/Tasmota/issues/21740)
+- Skip MQTT response if commands are executed prefixed with ``Backlog2`` (no delay) or ``Backlog3`` [#21740](https://github.com/arendst/Tasmota/issues/21740)
 - Extend command ``SetOption147 1`` to disable publish of IRReceived MQTT messages [#21574](https://github.com/arendst/Tasmota/issues/21574)
 - NeoPool data validation and communication statistics default enabled for ESP32 only [#21721](https://github.com/arendst/Tasmota/issues/21721)
 - ESP32 support for power and energy limit checks, like ``MaxEnergy2`` per phase [#21695](https://github.com/arendst/Tasmota/issues/21695)

tasmota/tasmota_support/support_command.ino

@@ -374,7 +374,7 @@ void CommandHandler(char* topicBuf, char* dataBuf, uint32_t data_len) {
   }
 
   char stemp1[TOPSZ];
-  GetFallbackTopic_P(stemp1, "");  // Full Fallback topic = cmnd/DVES_xxxxxxxx_fb/
+  GetFallbackTopic_P(stemp1, "");        // Full Fallback topic = cmnd/DVES_xxxxxxxx_fb/
   TasmotaGlobal.fallback_topic_flag = (!strncmp(topicBuf, stemp1, strlen(stemp1)));
 
   char *type = strrchr(topicBuf, '/');   // Last part of received topic is always the command (type)
@@ -384,13 +384,13 @@ void CommandHandler(char* topicBuf, char* dataBuf, uint32_t data_len) {
   if (type != nullptr) {
     type++;
     uint32_t i;
-    int nLen; // strlen(type)
+    int nLen;                            // strlen(type)
     char *s = type;
     for (nLen = 0; *s; s++, nLen++) {
       *s=toupper(*s);
     }
     i = nLen;
-    if (i > 0) { // may be 0
+    if (i > 0) {                         // may be 0
       while (isdigit(type[i-1])) {
         i--;
       }
@@ -400,13 +400,17 @@ void CommandHandler(char* topicBuf, char* dataBuf, uint32_t data_len) {
       user_index = true;
     }
     type[i] = '\0';
+    if ((i > 1) && ('_' == type[0])) {
+      type++;                            // Skip leading _ in command
+      TasmotaGlobal.no_mqtt_response = true;
+    }
 
-    bool binary_data = (index > 299);        // Suppose binary data on topic index > 299
+    bool binary_data = (index > 299);    // Suppose binary data on topic index > 299
     if (!binary_data) {
       bool keep_spaces = ((strstr_P(type, PSTR("SERIALSEND")) != nullptr) && (index > 9));  // Do not skip leading spaces on (s)serialsend10 and up
       if (!keep_spaces) {
         while (*dataBuf && isspace(*dataBuf)) {
-          dataBuf++;                           // Skip leading spaces in data
+          dataBuf++;                     // Skip leading spaces in data
           data_len--;
         }
       }