node sdk can't establish websocket with rust server

[12144]

when i use featureprobe-server-sdk-node, the sdk try to establish websocket with rust server, but establish failed, and continuously report websocket error. i notice the sdk use socketio-client to connect websocket, the corresponding code is

  private async connectSocket() {
    const url = new URL(this._realtimeUrl);

    this._logger?.info('connect socket to ' + this._realtimeUrl + ' ' + url.pathname);
    const socket = io(this._realtimeUrl, { transports: ['websocket'], path: url.pathname });

    socket.on('connect', () => {
      this._logger?.info('connect socketio success');
      socket.emit('register', { key: this._serverSdkKey });
    });

    socket.on('update', () => {
      this._logger?.info('socketio recv update event');
      (async () => {
        await this._toggleSyncer.syncNow()
      })()
    });

    socket.on('connect_error', (error: Error) => {
      this._logger?.info(`socketio error ${error.message}`);
    })

    // this._socket = socket;
  }

but the 'connect' event listener nerver be triggered. i pick this code fragment out to reproduce the bug, and the error happened. i also tried go sdk and it can work well, both js sdk and node sdk can't work, i guess there is something wrong between socketio-client and rust server

const client = require("socket.io-client");

const { io } = client;

function main() {
  const socket = io("http://localhost:4011/realtime", {
    path: "/realtime",
    transports: ["websocket"],
  });

  socket.on("connect", () => {
    console.log("connected to AB");
  });

  socket.on("connect_error", (error) => {
    console.log(`socketio error ${error}`);
  });
}

main();