WebRTC111 error: DOMException [InternalError: "Cannot create an offer with no local tracks, no offerToReceiveAudio/Video, and no DataChannel

I am building streaming service using webrtc+janusgateway+streamCapture.

This, starts streaming video:

  public streamVideo() {
    var video = $('#video1').get(0);
        var stream;

    video.onplay = () => {
      if (video.captureStream) {
        stream = video.captureStream();
      } else if (video.mozCaptureStream) {
        stream = video.mozCaptureStream();
      } else {
        alert('captureStream() not supported');
      }

            console.log(stream);
      $("#secondvideoforll").get(0).srcObject = stream;

    this.sfutest.createOffer(
      {
        media: { audioRecv: 0, videoRecv: 0, audioSend: 1, videoSend: 1}, // Publishers are sendonly
        stream: stream,
        success: (jsep) => {
          Janus.debug("Got publisher SDP!");
          Janus.debug(jsep);
          var publish = { "request": "configure", "audio": 1, "video": 1 };
          this.sfutest.send({"message": publish, "jsep": jsep});
        },
        error: (error) => {
          Janus.error("WebRTC111 error:", error);
        }
      });
    }
  }

Video playback works perfectly, but when i try to create an offer(and further addStream). I get this error:

WebRTC111 error: DOMException [InternalError: "Cannot create an offer with no local tracks, no offerToReceiveAudio/Video, and no DataChannel."
code: 0
nsresult: 0x0]

The same offer creation(without the stream parameter) works for webcam streeming, but not for video streaming.

The main difference i found is that webcam uses: LocalMediaStream, while my streamCapture uses MediaStream.

Any ideas on this one?

When calling video.captureStream() getTracks() returns empty array, but after 1.5 seconds, it returns tracks as expected.

Error produced if no tracks are added: WebRTC111 error: DOMException [InternalError: "Cannot create an offer with no local tracks, no offerToReceiveAudio/Video, and no DataChannel

Adding this for doc purposes, as others might find this confusing.

Solution:

setInterval(function(){
// We wait till the mediaTracks are added to mediaStream
console.log(stream.getTracks());
// Further actions with the mediaStream
}, 1000);

Thanks!

Reference: https://github.com/w3c/webrtc-pc/issues/923