Can't load from assets static page

[PrzemyslawPluszowy]

Hello, i try to create plugin, one of task is run server with static page, i have problem to serve static file

  final int _port;
  final String _host;

  WebHttpServer({
    String host = '127.0.0.1',
    int port = 9091,
  })  : _port = port,
        _host = host;

  final _staticHandler = createAssetHandler(
      rootPath: 'assets/web/', defaultDocument: 'index.html');

  Future<void> start() async {
    log('HIVE VIEW CE: Starting HTTP Server');
    var handler = const Pipeline()
        .addMiddleware(corsHeaders())
        .addHandler(_staticHandler);

    await shelf_io.serve(
      handler,
      _host,
      _port,
    );
    log('HIVE VIEW CE: HTTP Server started on http://$_host:$_port');
  }
}```

server start but can't load index.html
i think problem is path because this is plugin with assets