Usermods on Steroids: A Plugin Framework

usermods/DHT/DHT.cpp

@@ -20,6 +20,8 @@
 #define DHTTYPE DHT_TYPE_21
 #elif USERMOD_DHT_DHTTYPE == 22
 #define DHTTYPE DHT_TYPE_22
+#else
+#error Invalid USERMOD_DHT_DHTTYPE
 #endif
 
 // Connect pin 1 (on the left) of the sensor to +5V
@@ -57,11 +59,11 @@
 
 DHT_nonblocking dht_sensor(DHTPIN, DHTTYPE);
 
-class UsermodDHT : public Usermod {
+class UsermodDHT : public Usermod, public TemperatureSensor, public HumiditySensor {
   private:
     unsigned long nextReadTime = 0;
     unsigned long lastReadTime = 0;
-    float humidity, temperature = 0;
+    float tempC = 0, humidity = 0, temperature = 0;
     bool initializing = true;
     bool disabled = false;
     #ifdef USERMOD_DHT_MQTT
@@ -89,6 +91,8 @@ class UsermodDHT : public Usermod {
       #ifdef USERMOD_DHT_STATS
       nextResetStatsTime = millis() + 60*60*1000;
       #endif
+      pluginManager.registerTemperatureSensor(*this, "DHT");
+      pluginManager.registerHumiditySensor(*this, "DHT");
     }
 
     void loop() {
@@ -112,13 +116,14 @@ class UsermodDHT : public Usermod {
       }
       #endif
 
-      float tempC;
       if (dht_sensor.measure(&tempC, &humidity)) {
         #ifdef USERMOD_DHT_CELSIUS
         temperature = tempC;
         #else
         temperature = tempC * 9 / 5 + 32;
         #endif
+        _isTemperatureValid = true;
+        _isHumidityValid = true;
 
         #ifdef USERMOD_DHT_MQTT
         // 10^n where n is number of decimal places to display in mqtt message. Please adjust buff size together with this constant
@@ -168,6 +173,8 @@ class UsermodDHT : public Usermod {
 
       if (((millis() - lastReadTime) > 10*USERMOD_DHT_MEASUREMENT_INTERVAL)) {
         disabled = true;
+        _isTemperatureValid = false;
+        _isHumidityValid = false;
       }
     }
 
@@ -242,8 +249,11 @@ class UsermodDHT : public Usermod {
       return USERMOD_ID_DHT;
     }
 
+  private:
+    float do_getTemperatureC() override { return tempC; }
+    float do_getHumidity() override { return humidity; }
 };
 
 
 static UsermodDHT dht;
-REGISTER_USERMOD(dht);
+REGISTER_USERMOD(dht);

usermods/Temperature/Temperature.cpp

@@ -141,6 +141,7 @@ void UsermodTemperature::setup() {
   }
   lastMeasurement = millis() - readingInterval + 10000;
   initDone = true;
+  pluginManager.registerTemperatureSensor(*this, _name);
 }
 
 void UsermodTemperature::loop() {
@@ -165,11 +166,15 @@ void UsermodTemperature::loop() {
   if (now - lastTemperaturesRequest >= 750 /* 93.75ms per the datasheet but can be up to 750ms */) {
     readTemperature();
     if (getTemperatureC() < -100.0f) {
-      if (++errorCount > 10) sensorFound = 0;
+      if (++errorCount > 10) {
+        sensorFound = 0;
+        _isTemperatureValid = false;
+      }
       lastMeasurement = now - readingInterval + 300; // force new measurement in 300ms
       return;
     }
     errorCount = 0;
+    _isTemperatureValid = true;
 
 #ifndef WLED_DISABLE_MQTT
     if (WLED_MQTT_CONNECTED) {
@@ -380,4 +385,4 @@ static uint16_t mode_temperature() {
 
 
 static UsermodTemperature temperature;
-REGISTER_USERMOD(temperature);
+REGISTER_USERMOD(temperature);

usermods/Temperature/UsermodTemperature.h

@@ -16,7 +16,7 @@
 #define USERMOD_DALLASTEMPERATURE_MEASUREMENT_INTERVAL 60000
 #endif
 
-class UsermodTemperature : public Usermod {
+class UsermodTemperature : public Usermod, public TemperatureSensor {
 
   private:
 
@@ -71,6 +71,7 @@ class UsermodTemperature : public Usermod {
 #ifndef WLED_DISABLE_MQTT
     void publishHomeAssistantAutodiscovery();
 #endif
+    float do_getTemperatureC() override { return temperature; }
 
     static UsermodTemperature* _instance; // to overcome nonstatic getTemperatureC() method and avoid UsermodManager::lookup(USERMOD_ID_TEMPERATURE);
 
@@ -107,4 +108,3 @@ class UsermodTemperature : public Usermod {
 
     void appendConfigData() override;
 };
-

usermods/UM_DummySensor/README.md

@@ -0,0 +1,4 @@
+# Dummy usermod to simulate random sensor readings.
+
+Use `UM_PluginDemo` and `UM_DummySensor` together as an example for how direct interactions between
+usermods can be realized through the plugin API.

usermods/UM_DummySensor/UM_DummySensor.cpp

@@ -0,0 +1,104 @@
+/**
+ * (c) 2026 Joachim Dick
+ * Licensed under the EUPL v. 1.2 or later
+ */
+
+#include "wled.h"
+#include "PluginAPI/custom/DummySensor/DummySensor.h"
+
+//--------------------------------------------------------------------------------------------------
+
+static constexpr char _name[] = "Dummy-Sensor";
+
+/** Dummy usermod implementation that simulates random sensor readings.
+ */
+class UM_DummySensor : public Usermod, public DummySensor, public TemperatureSensor, public HumiditySensor
+{
+
+  // ----- usermod functions -----
+
+  void setup() override
+  {
+    // register sensor plugins
+    pluginManager.registerTemperatureSensor(*this, _name);
+    pluginManager.registerHumiditySensor(*this, _name);
+    // this dummy can deliver readings instantly
+    _isTemperatureValid = true;
+    _isHumidityValid = true;
+  }
+
+  void loop() override {}
+
+  // ----- DummySensor (our own) custom plugin functions -----
+
+  void enableTemperatureSensor() override
+  {
+    if (!_isTemperatureSensorEnabled)
+      pluginManager.registerTemperatureSensor(*this, _name);
+    _isTemperatureSensorEnabled = true;
+  }
+
+  void disableTemperatureSensor() override
+  {
+    if (_isTemperatureSensorEnabled)
+      pluginManager.unregisterTemperatureSensor(*this);
+    _isTemperatureSensorEnabled = false;
+  }
+
+  bool isTemperatureSensorEnabled() override { return _isTemperatureSensorEnabled; }
+
+  void enableHumiditySensor() override
+  {
+    if (!_isHumiditySensorEnabled)
+      pluginManager.registerHumiditySensor(*this, _name);
+    _isHumiditySensorEnabled = true;
+  }
+
+  void disableHumiditySensor() override
+  {
+    if (_isHumiditySensorEnabled)
+      pluginManager.unregisterHumiditySensor(*this);
+    _isHumiditySensorEnabled = false;
+  }
+
+  bool isHumiditySensorEnabled() override { return _isHumiditySensorEnabled; }
+
+  // ----- TemperatureSensor plugin functions -----
+
+  /// @copydoc TemperatureSensor::do_getTemperatureC()
+  float do_getTemperatureC() override { return readTemperature(); }
+
+  // ----- HumiditySensor plugin functions -----
+
+  /// @copydoc HumiditySensor::do_getHumidity()
+  float do_getHumidity() override { return readHumidity(); }
+
+  // ----- internal processing functions -----
+
+  /// The dummy implementation to simulate temperature values (based on perlin noise).
+  float readTemperature()
+  {
+    const int32_t raw = perlin16(strip.now * 8) - 0x8000;
+    // simulate some random temperature around 20°C
+    return 20.0f + raw / 65535.0f * 30.0f;
+  }
+
+  /// The dummy implementation to simulate humidity values (a sine wave).
+  float readHumidity()
+  {
+    const int32_t raw = beatsin16_t(1);
+    // simulate some random humidity between 10% and 90%
+    return 10.0f + raw / 65535.0f * 80.0f;
+  }
+
+  // ----- member variables -----
+
+  bool _isTemperatureSensorEnabled = false;
+  bool _isHumiditySensorEnabled = false;
+};
+
+//--------------------------------------------------------------------------------------------------
+
+static UM_DummySensor um_DummySensor;
+REGISTER_USERMOD(um_DummySensor);
+DEFINE_PLUGIN_API(DummySensor, um_DummySensor);

usermods/UM_DummySensor/library.json

@@ -0,0 +1,4 @@
+{
+  "name": "UM_DummySensor",
+  "build": { "libArchive": false }
+}

usermods/UM_PluginDemo/README.md

@@ -0,0 +1,4 @@
+# Examples for writing custom plugins.
+
+Use `UM_PluginDemo` and `UM_DummySensor` together as an example for how direct interactions between
+usermods can be realized through the plugin API.