feat: enhance Dockerfile for SQLite support and update main.go for MySQL connection; add sensor creation endpoint and improve wait-for-mqtt script

cmd/server/main.go

@@ -29,16 +29,16 @@ func main() {
 		log.Fatalf("failed to load config: %v", err)
 	}
 
-	// connect to database
+	// connect to MySQL database
 	dsn := fmt.Sprintf("%s:%s@tcp(%s:%d)/%s?parseTime=true", cfg.Database.User, cfg.Database.Password, cfg.Database.Host, cfg.Database.Port, cfg.Database.Name)
-	db, err := sql.Open("mysql", dsn)
+	sqlDB, err := sql.Open("mysql", dsn)
 	if err != nil {
 		log.Fatalf("failed to connect to database: %v", err)
 	}
-	defer db.Close()
+	defer sqlDB.Close()
 
 	// test connection
-	if err := db.Ping(); err != nil {
+	if err := sqlDB.Ping(); err != nil {
 		log.Fatalf("failed to ping database: %v", err)
 	}
 	log.Println("connected to database")
@@ -55,7 +55,7 @@ func main() {
 	// connect to MQTT broker (best-effort)
 	var mq *mqttclient.Client
 	// initialize sqlite for state messages
-	var db *storage.DB
+	var stateDB *storage.DB
 	{
 		dbPath := os.Getenv("SQLITE_PATH")
 		if dbPath == "" {
@@ -65,8 +65,8 @@ func main() {
 		if err != nil {
 			log.Printf("warning: sqlite init failed: %v", err)
 		} else {
-			db = dbInit
-			storage.SetDefault(db)
+			stateDB = dbInit
+			storage.SetDefault(stateDB)
 		}
 	}
 	if cfg.MQTT.Broker != "" {
@@ -108,7 +108,7 @@ func main() {
 	r.Use(gin.Recovery())
 	r.Use(middleware.GinLogger())
 
-	h := &handler.Handler{DB: db, JWTSecret: cfg.Server.JWTSecret}
+	h := &handler.Handler{DB: sqlDB, JWTSecret: cfg.Server.JWTSecret}
 
 	// Public routes
 	r.GET("/health", h.Health)
@@ -122,6 +122,9 @@ func main() {
 	auth := r.Group("/")
 	auth.Use(middleware.AuthMiddleware(cfg.Server.JWTSecret))
 	auth.GET("/protected", h.Protected)
+	auth.GET("/mqttping", h.MQTTPing)
+	auth.GET("/messages", handler.GetMessages)
+	auth.POST("/sensors", h.CreateSensor)
 
 	// Device CRUD routes
 	auth.POST("/devices", h.CreateDevice)
@@ -152,15 +155,10 @@ func main() {
 	if mq != nil {
 		mq.Close()
 	}
-	if db != nil {
-		db.Close()
+	if stateDB != nil {
+		stateDB.Close()
 	}
 	log.Println("server exiting")
 }
 
-func getJWTSecret() string {
-	if s := os.Getenv("JWT_SECRET"); s != "" {
-		return s
-	}
-	return "secret"
-}
+// removed unused getJWTSecret helper; configuration provides JWTSecret