Golang mux server multple page app support

main.go

router.PathPrefix("/").Handler(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		const staticPath = "../dist"
		const indexPath = "index.html"
		fileServer := http.FileServer(http.Dir(staticPath))
		path, err := filepath.Abs(r.URL.Path)
		if err != nil {
			http.Error(w, err.Error(), http.StatusBadRequest)
			return
		}
		path = filepath.Join(staticPath, path)
		_, err = os.Stat(path)
		if os.IsNotExist(err) {
			// file does not exist, serve index.html
			http.ServeFile(w, r, filepath.Join(staticPath, indexPath))
			return
		} else if err != nil {
			http.Error(w, err.Error(), http.StatusInternalServerError)
			return
		}
		fileServer.ServeHTTP(w, r)
	}))