Server sends invalid websocket frame: RSV1 must be clear

[mStirner]

Seems like this happens after using newer node version than 16.
On v20.11.0, this happens when the "Detect broken connections" is enabled.

See:

• RangeError: Invalid WebSocket frame: RSV1 must be clear connector#38
• Detecting broken connections fails with RSV1 must be clear on node v20.11.0 websockets/ws#2193

Reason for that is how the websocket upgraded is handled.
Instead of listen for the upgrade event, the upgrade is done in the request event.

After handling the upgrade event, it seems the problem is solved.
Test and add the following code to the http servers:

server.on("upgrade", (req, socket, head) => {

    let res = new http.ServerResponse(req);
    res.assignSocket(socket)

    res.on("finish", () => {
        res.socket.destroy();
    });

    app(req, res);

});