ESP32 Emulator: веб-морда контроллера гроубокса поверх MQTT

Go-сервис без внешних фронтенд-зависимостей: embedded HTML-страница
с SVG-изображением платы (датчик + вентилятор + свет + помпа) и
Server-Sent Events для live-обновления. Слушает devices/+/commands
и реально отвечает ack'ом, публикует devices/{id}/telemetry —
протокол зеркалит ingest-service/device-control-service основного
репозитория, общего кода между репозиториями нет. Дефолтные
external_id (sensor-1/fan-1/light-1/pump-1) совпадают с
DemoGrowboxSeeder платформы.

cmd/emulator/main.go

@@ -0,0 +1,83 @@
+// Command emulator serves a small web UI that stands in for an ESP32
+// growbox controller: a sensor slot (publishes temperature/humidity
+// telemetry) and three actuator slots (fan/light/pump — react live to
+// commands the platform sends over MQTT). See README.md for the protocol
+// this speaks and why it exists as a standalone tool.
+package main
+
+import (
+	"context"
+	"log/slog"
+	"net/http"
+	"os"
+	"os/signal"
+	"syscall"
+	"time"
+
+	"git.cactoz.su/cacto/home_automation_emulator/internal/httpserver"
+	"git.cactoz.su/cacto/home_automation_emulator/internal/mqttclient"
+	"git.cactoz.su/cacto/home_automation_emulator/internal/state"
+)
+
+func main() {
+	logger := slog.New(slog.NewTextHandler(os.Stdout, nil))
+
+	brokerURL := getEnv("MQTT_BROKER_URL", "tcp://localhost:1883")
+	httpAddr := ":" + getEnv("HTTP_PORT", "8091")
+
+	store := state.NewStore()
+
+	mqttClient, err := mqttclient.Connect(mqttclient.Config{
+		BrokerURL: brokerURL,
+		ClientID:  "esp32-emulator",
+	}, logger)
+	if err != nil {
+		logger.Error("mqtt connect failed", "broker", brokerURL, "error", err)
+		os.Exit(1)
+	}
+	defer mqttClient.Close()
+
+	if err := mqttClient.SubscribeCommands(func(externalID, action string, level float64, hasLevel bool) {
+		reported, ok := store.ApplyCommand(externalID, action, level, hasLevel)
+		if !ok {
+			logger.Warn("command for unknown device ignored", "device_id", externalID, "action", action)
+			return
+		}
+		logger.Info("command applied", "device_id", externalID, "action", action)
+		if err := mqttClient.PublishAck(externalID, reported); err != nil {
+			logger.Error("publish ack failed", "device_id", externalID, "error", err)
+		}
+	}); err != nil {
+		logger.Error("mqtt subscribe failed", "error", err)
+		os.Exit(1)
+	}
+
+	srv := &http.Server{
+		Addr:    httpAddr,
+		Handler: httpserver.New(store, mqttClient, logger),
+	}
+
+	go func() {
+		logger.Info("http server listening", "addr", httpAddr, "mqtt_broker", brokerURL)
+		if err := srv.ListenAndServe(); err != nil && err != http.ErrServerClosed {
+			logger.Error("http server failed", "error", err)
+			os.Exit(1)
+		}
+	}()
+
+	ctx, stop := signal.NotifyContext(context.Background(), syscall.SIGINT, syscall.SIGTERM)
+	defer stop()
+	<-ctx.Done()
+
+	logger.Info("shutting down")
+	shutdownCtx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+	defer cancel()
+	_ = srv.Shutdown(shutdownCtx)
+}
+
+func getEnv(key, fallback string) string {
+	if v := os.Getenv(key); v != "" {
+		return v
+	}
+	return fallback
+}