add root file handler before StartPay

fs_wrapper_handler.go

+package main
+
+import (
+	"net/http"
+)
+
+type NotFoundRedirectRespWr struct {
+	http.ResponseWriter // We embed http.ResponseWriter
+	status              int
+}
+
+func (w *NotFoundRedirectRespWr) WriteHeader(status int) {
+	w.status = status // Store the status for our own use
+	if status != http.StatusNotFound {
+		w.ResponseWriter.WriteHeader(status)
+	}
+}
+
+func (w *NotFoundRedirectRespWr) Write(p []byte) (int, error) {
+	if w.status != http.StatusNotFound {
+		return w.ResponseWriter.Write(p)
+	}
+	return len(p), nil // Lie that we successfully written it
+}
+
+func wrapHandler(h http.Handler) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		if r.URL.Path == "/" {
+			StartPay(w, r)
+		} else {
+			h.ServeHTTP(w, r)
+		}
+	}
+}

main.go

 func main() {
 	//readConfig()
 	readConfigForTest()
-	http.HandleFunc("/", StartPay)
+
 	http.HandleFunc("/choosePayment", choosePayment)
 	http.HandleFunc("/rpnNameAndCard", rpnNameAndCard)
 	// http.HandleFunc("/", Index)
 	// http.HandleFunc("/insert", Insert)
 	// http.HandleFunc("/update", Update)
 	// http.HandleFunc("/delete", Delete)
+	fs := wrapHandler(http.FileServer(http.Dir("./PG")))
+	http.HandleFunc("/", fs)
 	http.ListenAndServe(":8080", nil)
 	log.Println("Server started on: http://localhost:8080")
 }