Ampel class instead of util functions

ampel-firmware/ampel-firmware.ino

@@ -80,16 +80,15 @@ void setup() {
 
   led_effects::setupRing();
 
-  util::initialize();
   sensor::initialize();
 
   Serial.print(F("Sensor ID: "));
-  Serial.println(SENSOR_ID);
+  Serial.println(ampel.sensorId);
   Serial.print(F("Board    : "));
   Serial.println(BOARD);
 
 #ifdef AMPEL_WIFI
-  WiFiConnect(SENSOR_ID);
+  WiFiConnect(ampel.sensorId);
 
   Serial.print(F("WiFi - Status: "));
   Serial.println(WiFi.status());
@@ -101,7 +100,7 @@ void setup() {
 
     ntp::initialize();
 
-    if (MDNS.begin(SENSOR_ID.c_str())) { // Start the mDNS responder for SENSOR_ID.local
+    if (MDNS.begin(ampel.sensorId.c_str())) { // Start the mDNS responder for SENSOR_ID.local
       MDNS.addService("http", "tcp", 80);
       Serial.println(F("mDNS responder started"));
     } else {
@@ -109,7 +108,7 @@ void setup() {
     }
 
 #  ifdef AMPEL_MQTT
-    mqtt::initialize("CO2sensors/" + SENSOR_ID);
+    mqtt::initialize("CO2sensors/" + ampel.sensorId);
 #  endif
   }
 #endif

ampel-firmware/csv_writer.cpp

@@ -78,7 +78,7 @@ namespace csv_writer {
   }
 #endif
 
-  const String filename = "/" + SENSOR_ID + ".csv";
+  const String filename = "/" + ampel.sensorId + ".csv";
 
   int getAvailableSpace() {
     return getTotalSpace() - getUsedSpace();

ampel-firmware/util.cpp

@@ -51,21 +51,16 @@ namespace ntp {
   }
 }
 
-namespace util {
-  void initialize() {
-    // Define SENSOR ID
-    // Add callbacks
-    sensor_console::defineIntCommand("set_time", ntp::setLocalTime, " 1618829570 (Sets time to the given UNIX time)");
-    sensor_console::defineCommand("free", []() {
-      Serial.print(F("Free heap space : "));
-      Serial.print(get_free_heap_size());
-      Serial.println(F(" bytes."));
-    }, " (Displays available heap space)");
-  }
-}
-
 uint32_t max_loop_duration = 0;
 
-//FIXME: Remove every instance of Strings, to avoid heap fragmentation problems. (Start:  "Free heap space : 17104 bytes")
-// See more https://cpp4arduino.com/2020/02/07/how-to-format-strings-without-the-string-class.html
-const String SENSOR_ID = "ESP" + macToID();
+Ampel::Ampel() :
+    sensorId("ESP" + macToID()) {
+  sensor_console::defineIntCommand("set_time", ntp::setLocalTime, " 1618829570 (Sets time to the given UNIX time)");
+  sensor_console::defineCommand("free", []() {
+    Serial.print(F("Free heap space : "));
+    Serial.print(get_free_heap_size());
+    Serial.println(F(" bytes."));
+  }, " (Displays available heap space)");
+}
+
+const Ampel ampel;

ampel-firmware/util.h

@@ -26,8 +26,6 @@ namespace ntp {
 }
 
 namespace util {
-  void initialize();
-
   template<typename Tpa, typename Tpb>
   inline auto min(const Tpa &a, const Tpb &b) -> decltype(a < b ? a : b) {
     return b < a ? b : a;
@@ -38,10 +36,15 @@ namespace util {
     return b > a ? b : a;
   }
 }
+class Ampel {
+public:
+  const String sensorId;
+  Ampel();
+};
 
 //NOTE: Only use seconds() for duration comparison, not timestamps comparison. Otherwise, problems happen when millis roll over.
 #define seconds() (millis() / 1000UL)
 extern uint32_t max_loop_duration;
-const extern String SENSOR_ID;
+extern const Ampel ampel;
 
 #endif

ampel-firmware/web_server.cpp

@@ -184,7 +184,7 @@ namespace web_server {
     http.begin();
 
     Serial.print(F("You can access this sensor via http://"));
-    Serial.print(SENSOR_ID);
+    Serial.print(ampel.sensorId);
     Serial.print(F(".local (might be unstable) or http://"));
     Serial.println(WiFi.localIP());
   }
@@ -212,7 +212,7 @@ namespace web_server {
     char content[2000]; // Update if needed
     // INFO - Header size : 1767 - Body size : 1812 - Script size : 1909
 
-    snprintf_P(content, sizeof(content), header_template, sensor::co2, SENSOR_ID.c_str(),
+    snprintf_P(content, sizeof(content), header_template, sensor::co2, ampel.sensorId.c_str(),
         WiFi.localIP().toString().c_str()
 #ifdef AMPEL_CSV
         , csv_writer::filename.c_str()
@@ -225,7 +225,7 @@ namespace web_server {
     http.send_P(200, PSTR("text/html"), content);
 
     // Body
-    snprintf_P(content, sizeof(content), body_template, SENSOR_ID.c_str(), sensor::co2, sensor::temperature,
+    snprintf_P(content, sizeof(content), body_template, ampel.sensorId.c_str(), sensor::co2, sensor::temperature,
         sensor::humidity, sensor::timestamp, config::measurement_timestep,
 #ifdef AMPEL_CSV
         csv_writer::last_successful_write, config::csv_interval, csv_writer::getAvailableSpace() / 1024,
@@ -237,9 +237,9 @@ namespace web_server {
         lorawan::connected ? "Yes" : "No", LMIC_FREQUENCY_PLAN, lorawan::last_transmission,
         config::lorawan_sending_interval,
 #endif
-        config::temperature_offset, config::auto_calibrate_sensor ? "Yes" : "No", SENSOR_ID.c_str(), SENSOR_ID.c_str(),
-        WiFi.localIP().toString().c_str(), WiFi.localIP().toString().c_str(), get_free_heap_size(), max_loop_duration,
-        BOARD, dd, hh, mm, ss);
+        config::temperature_offset, config::auto_calibrate_sensor ? "Yes" : "No", ampel.sensorId.c_str(),
+        ampel.sensorId.c_str(), WiFi.localIP().toString().c_str(), WiFi.localIP().toString().c_str(),
+        get_free_heap_size(), max_loop_duration, BOARD, dd, hh, mm, ss);
 
     Serial.print(F(" - Body size : "));
     http.sendContent(content);
@@ -248,7 +248,7 @@ namespace web_server {
     // Script
     snprintf_P(content, sizeof(content), script_template
 #ifdef AMPEL_CSV
-        , csv_writer::filename.c_str(), SENSOR_ID.c_str()
+        , csv_writer::filename.c_str(), ampel.sensorId.c_str()
 #endif
         );