node ws->express passthrough

example.js

var httpServer = http.createServer(app);
var ServerResponse = http.ServerResponse;
var wsServer = new WebSocketServer({ server: httpServer });

  wsServer.on('connection', function(ws) {
    var response = new ServerResponse(ws.upgradeReq);
    response.writeHead = function (statusCode) {
      if (statusCode > 200) ws.close();
    }; //Construct response that will kill the websocket.
    
    var sockHandled = false;
    ws.upgradeReq.getWebSocket = function(){ //Wrap socket in function to check if it's accessed.
      sockHandled = true;
      return ws;
    };
    
    app.handle(ws.upgradeReq, response, function() { //Pass to Express, and check if handled, if not, kill the socket.
      if (!sockHandled) {
        ws.close();
      }
    });
  });
httpServer.listen(8080);