add mqtt module

platformio.ini

@@ -42,6 +42,7 @@ lib_deps =
     https://github.com/dsbaars/GxEPD2#universal_pin
     https://github.com/tzapu/WiFiManager.git#v2.0.17
     rblb/Nostrduino@1.2.8
+    knolleary/PubSubClient@2.8
     
 [env:lolin_s3_mini]
 extends = btclock_base

src/lib/config.cpp

@@ -92,6 +92,12 @@ void setup()
     setupBitaxeFetchTask();
   }
 
+  if (preferences.getBool("mqttEnabled", DEFAULT_MQTT_ENABLED))
+  {
+    setupMqtt();
+    setupMqttTask();
+  }
+
   setupButtonTask();
   setupOTA();
 

src/lib/config.hpp

@@ -29,6 +29,7 @@
 #include "PCA9685.h"
 #include "BH1750.h"
 #endif
+#include "lib/mqtt.hpp"
 
 #define NTP_SERVER "pool.ntp.org"
 #define DEFAULT_TIME_OFFSET_SECONDS 3600

src/lib/defaults.hpp

@@ -56,6 +56,9 @@
 #define DEFAULT_BITAXE_ENABLED false
 #define DEFAULT_BITAXE_HOSTNAME "bitaxe1"
 
+#define DEFAULT_MQTT_ENABLED false
+#define DEFAULT_MQTT_ROOTTOPIC "home/"
+
 #define DEFAULT_ZAP_NOTIFY_ENABLED false
 #define DEFAULT_ZAP_NOTIFY_PUBKEY "b5127a08cf33616274800a4387881a9f98e04b9c37116e92de5250498635c422"
 #define DEFAULT_LED_FLASH_ON_ZAP true

src/lib/mqtt.cpp

@@ -0,0 +1,112 @@
+#include "mqtt.hpp"
+
+TaskHandle_t mqttTaskHandle = NULL;
+
+WiFiClient wifiClient;
+PubSubClient client(wifiClient);
+
+void onMqttCallback(char* topic, byte* payload, unsigned int length)
+{
+    Serial.println("MQTT message arrived");
+}
+
+boolean connectMqtt()
+{
+    boolean result = client.connect("btclockClient");
+    if (!result)
+    {
+        Serial.println("[MQTT] could not connect");
+    }
+    return result;
+}
+
+void setupMqtt()
+{
+    const String host = preferences.getString("mqttHost", "");
+    if (host == "")
+    {
+        Serial.println("[MQTT] host not set");
+        return;
+    }
+    Serial.print("[MQTT] host: ");
+    Serial.println(host.c_str());
+
+    IPAddress addr((uint32_t)0);
+    if(!WiFi.hostByName(host.c_str(), addr))
+    {
+        Serial.println("[MQTT] host lookup fail");
+        return;
+    }
+    client.setServer(addr, 1883);
+    client.setCallback(onMqttCallback);
+
+    connectMqtt();
+}
+
+// avoid circular deps, just forward declare externs used here.
+bool hasLightLevel();
+float getLightLevel();
+String getMyHostname();
+
+void mqttTask(void *pvParameters)
+{
+    int t=0;
+    while (1)
+    {
+        client.loop();
+        vTaskDelay(pdMS_TO_TICKS(1000));
+        if (t++ % 10 == 0)
+        {
+            if (!client.connected())
+            {
+                // reconnect
+                if (!connectMqtt())
+                    return;
+            }
+
+            if (hasLightLevel())
+            {
+                std::string lux_s = std::to_string(static_cast<int>(std::round(getLightLevel())));
+                publish("sensors/lux", lux_s.c_str());
+            }
+            if (WiFi.isConnected())
+            {
+                int8_t rssi = WiFi.RSSI();
+                std::string rssi_s = std::to_string(static_cast<int>(rssi));
+                publish("wifi/rssi", rssi_s.c_str());
+            }
+            std::string heap_free_s = std::to_string(static_cast<int>(ESP.getFreeHeap()));
+            publish("mem/heap_free", heap_free_s.c_str());
+            std::string heap_size_s = std::to_string(static_cast<int>(ESP.getHeapSize()));
+            publish("mem/heap_size", heap_size_s.c_str());
+        }
+    }
+}
+
+void setupMqttTask()
+{
+    xTaskCreate(mqttTask, "mqttTask", 8192, NULL, 10, &mqttTaskHandle);
+}
+
+void publish(const char *topic, const char *value)
+{
+    if (!client.connected())
+    {
+        Serial.println("[MQTT] not connected");
+        return;
+    }
+
+    const String hostname = getMyHostname();
+    const String rootTopic = preferences.getString("mqttRootTopic", DEFAULT_MQTT_ROOTTOPIC);
+    String fullTopic = rootTopic;
+    if (!rootTopic.endsWith("/") && rootTopic != "")
+    {
+        fullTopic += "/";
+    }
+    fullTopic += hostname + "/" + topic;
+
+    if (!client.publish(fullTopic.c_str(), value))
+    {
+        Serial.println("[MQTT] could not write");
+    }
+}

src/lib/mqtt.hpp

@@ -0,0 +1,9 @@
+#pragma once
+
+#include <Arduino.h>
+#include "lib/shared.hpp"
+#include "PubSubClient.h"
+
+void setupMqtt();
+void setupMqttTask();
+void publish(const char *key, const char *value);

src/lib/webserver.cpp

@@ -510,7 +510,10 @@ void onApiSettingsPatch(AsyncWebServerRequest *request, JsonVariant &json)
                         settings["timePerScreen"].as<uint>() * 60);
   }
 
-  String strSettings[] = {"hostnamePrefix", "mempoolInstance", "nostrPubKey", "nostrRelay", "bitaxeHostname", "nostrZapPubkey", "httpAuthUser", "httpAuthPass", "gitReleaseUrl"};
+  String strSettings[] = {"hostnamePrefix", "mempoolInstance", "nostrPubKey", 
+                          "nostrRelay", "bitaxeHostname", "nostrZapPubkey", 
+                          "httpAuthUser", "httpAuthPass", "gitReleaseUrl",
+                          "mqttHost", "mqttRootTopic"};
 
   for (String setting : strSettings)
   {
@@ -546,7 +549,7 @@ void onApiSettingsPatch(AsyncWebServerRequest *request, JsonVariant &json)
                            "mdnsEnabled", "otaEnabled", "stealFocus",
                            "mcapBigChar", "useSatsSymbol", "useBlkCountdown",
                            "suffixPrice", "disableLeds", "ownDataSource",
-                           "mowMode", "suffixShareDot",
+                           "mowMode", "suffixShareDot", "mqttEnabled",
                            "flAlwaysOn", "flDisable", "flFlashOnUpd",
                            "mempoolSecure", "useNostr", "bitaxeEnabled",
                            "nostrZapNotify", "stagingSource", "httpAuthEnabled"};
@@ -711,6 +714,10 @@ void onApiSettingsGet(AsyncWebServerRequest *request)
   root["bitaxeEnabled"] = preferences.getBool("bitaxeEnabled", DEFAULT_BITAXE_ENABLED);
   root["bitaxeHostname"] = preferences.getString("bitaxeHostname", DEFAULT_BITAXE_HOSTNAME);
 
+  root["mqttEnabled"] = preferences.getBool("mqttEnabled", DEFAULT_MQTT_ENABLED);
+  root["mqttHost"] = preferences.getString("mqttHost", "");
+  root["mqttRootTopic"] = preferences.getString("mqttRootTopic", DEFAULT_MQTT_ROOTTOPIC);
+
   root["httpAuthEnabled"] = preferences.getBool("httpAuthEnabled", DEFAULT_HTTP_AUTH_ENABLED);
   root["httpAuthUser"] = preferences.getString("httpAuthUser", DEFAULT_HTTP_AUTH_USERNAME);
   root["httpAuthPass"] = preferences.getString("httpAuthPass", DEFAULT_HTTP_AUTH_PASSWORD);