Reworked MQTT-Reconnect and slight mem-improvement

src/logmessages.h

@@ -138,7 +138,7 @@ static const char ssidNotFoundInNvs[] PROGMEM = "SSID wurde im NVS nicht gefunde
 static const char wifiPwdNotFoundInNvs[] PROGMEM = "WLAN-Passwort wurde im NVS nicht gefunden.";
 static const char wifiStaticIpConfigNotFoundInNvs[] PROGMEM = "Statische WLAN-IP-Konfiguration wurde im NVS nicht gefunden.";
 static const char wifiHostnameNotSet[] PROGMEM = "Keine Hostname-Konfiguration im NVS gefunden.";
-static const char mqttConnFailed[] PROGMEM = "Verbindung fehlgeschlagen, versuche erneut in Kürze erneut";
+static const char mqttConnFailed[] PROGMEM = "Verbindung fehlgeschlagen, versuche in Kürze erneut";
 static const char restoredHostnameFromNvs[] PROGMEM = "Hostname aus NVS geladen";
 static const char currentVoltageMsg[] PROGMEM = "Aktuelle Batteriespannung";
 static const char voltageTooLow[] PROGMEM = "Batteriespannung niedrig";
@@ -151,3 +151,7 @@ static const char voltageCheckIntervalFromNVS[] PROGMEM = "Zyklus für Spannungs
 static const char warningLowVoltageFromNVS[] PROGMEM = "Spannungslevel (Batterie) fuer Warnung via Neopixel aus NVS geladen";
 static const char unableToRestoreLastRfidFromNVS[] PROGMEM = "Letzte RFID konnte nicht aus NVS geladen werden";
 static const char restoredLastRfidFromNVS[] PROGMEM = "Letzte RFID wurde aus NVS geladen";
+static const char failedOpenFileForWrite[] PROGMEM = "Öffnen der Datei für den Schreibvorgang fehlgeschlagen";
+static const char fileWritten[] PROGMEM = "Schreibe Datei";
+static const char writeFailed[] PROGMEM = "Schreibvorgang fehlgeschlagen";
+static const char writingFile[] PROGMEM = "Schreibe Datei";

src/logmessages_EN.h

@@ -151,3 +151,7 @@ static const char voltageCheckIntervalFromNVS[] PROGMEM = "Restored interval of
 static const char warningLowVoltageFromNVS[] PROGMEM = "Restored battery-voltage-level for warning via Neopixel from NVS";
 static const char unableToRestoreLastRfidFromNVS[] PROGMEM = "Unable to restore last RFID from NVS";
 static const char restoredLastRfidFromNVS[] PROGMEM = "Restored last RFID from NVS";
+static const char failedOpenFileForWrite[] PROGMEM = "Failed to open file for writing";
+static const char fileWritten[] PROGMEM = "File written";
+static const char writeFailed[] PROGMEM = "Write failed";
+static const char writingFile[] PROGMEM = "Writing file";

src/main.cpp

@@ -150,7 +150,6 @@ uint8_t nightLedBrightness = 2;                         // Brightness of Neopixe
 // MQTT
 bool enableMqtt = true;
 #ifdef MQTT_ENABLE
-    uint8_t mqttFailCount = 3;                          // Number of times mqtt-reconnect is allowed to fail. If >= mqttFailCount to further reconnects take place
     uint8_t const stillOnlineInterval = 60;             // Interval 'I'm still alive' is sent via MQTT (in seconds)
 #endif
 
@@ -413,20 +412,23 @@ void IRAM_ATTR onTimer() {
  * @param message
  */
 void createFile(fs::FS &fs, const char * path, const char * message) {
-    snprintf(logBuf, serialLoglength, "Writing file: %s\n", path);
+    //snprintf(logBuf, serialLoglength, "Writing file: %s\n", path);
+    snprintf(logBuf, serialLoglength, "%s: %s", (char *) FPSTR(writingFile), path);
     loggerNl(logBuf, LOGLEVEL_DEBUG);
     File file = fs.open(path, FILE_WRITE);
     if (!file) {
-        snprintf(logBuf, serialLoglength, "Failed to open file for writing");
+        snprintf(logBuf, serialLoglength, "%s", (char *) FPSTR(failedOpenFileForWrite));
+        //snprintf(logBuf, serialLoglength, "Failed to open file for writing");
         loggerNl(logBuf, LOGLEVEL_ERROR);
         return;
     }
     if (file.print(message)) {
-        snprintf(logBuf, serialLoglength, "File written");
+        //snprintf(logBuf, serialLoglength, "File written");
+        snprintf(logBuf, serialLoglength, "%s", (char *) FPSTR(fileWritten));
         loggerNl(logBuf, LOGLEVEL_DEBUG);
     } else {
-        Serial.println("Write failed");
-        snprintf(logBuf, serialLoglength, "Write failed");
+        //snprintf(logBuf, serialLoglength, "Write failed");
+        snprintf(logBuf, serialLoglength, "%s", (char *) FPSTR(writeFailed));
         loggerNl(logBuf, LOGLEVEL_ERROR);
     }
     file.close();
@@ -805,11 +807,20 @@ void postHeartbeatViaMqtt(void) {
 /* Connects/reconnects to MQTT-Broker unless connection is not already available.
     Manages MQTT-subscriptions.
 */
+uint32_t mqttLastRetryTimestamp = 0;
+
 bool reconnect() {
-  uint8_t maxRetries = 10;
   uint8_t connect = false;
+  uint8_t i = 0;
 
-  while (!MQTTclient.connected() && mqttFailCount < maxRetries) {
+  if (!mqttLastRetryTimestamp || millis() - mqttLastRetryTimestamp >= mqttRetryInterval * 1000) {
+      mqttLastRetryTimestamp = millis();
+  } else {
+      return false;
+  }
+
+  while (!MQTTclient.connected() && i < mqttMaxRetriesPerInterval) {
+    i++;
     snprintf(logBuf, serialLoglength, "%s %s", (char *) FPSTR(tryConnectMqttS), mqtt_server);
     loggerNl(logBuf, LOGLEVEL_NOTICE);
 
@@ -868,10 +879,8 @@ bool reconnect() {
 
         return MQTTclient.connected();
     } else {
-        snprintf(logBuf, serialLoglength, "%s: rc=%i (%d / %d)", (char *) FPSTR(mqttConnFailed), MQTTclient.state(), mqttFailCount+1, maxRetries);
+        snprintf(logBuf, serialLoglength, "%s: rc=%i (%d / %d)", (char *) FPSTR(mqttConnFailed), MQTTclient.state(), i, mqttMaxRetriesPerInterval);
         loggerNl(logBuf, LOGLEVEL_ERROR);
-        mqttFailCount++;
-        delay(500);
     }
   }
   return false;

src/settings.h

@@ -130,6 +130,8 @@ float voltageIndicatorHigh = 4.2;                   // Upper range for Neopixel-
 
 // (optional) Topics for MQTT
 #ifdef MQTT_ENABLE
+    uint16_t mqttRetryInterval = 15;                // Try to reconnect to MQTT-server every (n) seconds if connection is broken
+    uint8_t mqttMaxRetriesPerInterval = 1;          // Number of retries per time-interval (mqttRetryInterval). mqttRetryInterval 15 / mqttMaxRetriesPerInterval 1 => once every 15s
     #define DEVICE_HOSTNAME "ESP32-Tonuino-Leonie"                 // Name that that is used for MQTT
     static const char topicSleepCmnd[] PROGMEM = "Cmnd/Tonuino-Leonie/Sleep";
     static const char topicSleepState[] PROGMEM = "State/Tonuino-Leonie/Sleep";