Socket on message event isn't firing

Grafana k6 OSS Support
1

Below is my current k6 function that will open a connection, and then send a bunch of HTTP requests (callback) to my Azure Bot Service. However, the on(‘message’) event will never be fired, am I missing something here?

    export const openSocketConnection = (socketURL, callback) => {
    ws.connect(socketURL, function (socket) {
        socket.on('open', function open() {
            console.log('connected');
            callback();
            socket.close();
        });
        socket.on('message', function (message) {
            console.log(message)
        })

        socket.on('close', function () {
            console.log('disconnected');
        });
    })
}
2

Hi @phuhnguyen,

K6 unfortuantely doesn’t have “real” global event loop and so what ws.connect does is that it blocks until the connection is closed and calls the provided functions when an event occurs … but if one of the functions/callbacks gets blocked or closes the connection it will again be closed.

As far as I can see you do call some callback function in open and than you close the connection. So given tha above 2 things happen:

  1. While open is being executed message won’t be so if callback takes a while it will not get any calls to message
  2. You close the connection right after this so … message again will not have time to be called.

Hope this helps and good luck

3

The context is that Azure Bot Service uses HTTP request to send data but receive the response via Web Socket, thus I’m seeking out a way to simultaneously send HTTP request and receive data via Web Socket. Is it possible?

4

No, but I am pretty sure that if you don’t close the socket immediately you will get the message, but your mileage might vary.