Unable to apply custom filters after calling player.reset()

[vodlogic]

When player.reset() is called and a custom initial track selection is applied , it does not seem possible to re-initialise the player and attach the source.

Uncaught TypeError: Cannot read properties of null (reading 'setCustomInitialTrackSelectionFunction')
    at Object.setCustomInitialTrackSelectionFunction (MediaPlayer.js:1584:31)
    at HTMLButtonElement.<anonymous> (reset-test.html:27:12)

This also affects the capabilities filter and license request filters functions being applied after player.reset() is called.

This seems to be because customParametersModel is set to null in the reset() function, but it is never then re-initialised since this is only called in the MediaPlayer setup() function

dash.js/src/streaming/MediaPlayer.js

Line 185 in 2aad3e7

customParametersModel = CustomParametersModel(context).getInstance();

Below is a Quick demo showing setCustomInitialTrackSelectionFunction working when reset() is not applied beforehand but throws the error when reset is called beforehand.

<video height="200"></video>
<button id="withoutReset">Without Reset</button>
<button id="withReset">With Reset</button>
<script src="https://cdn.dashjs.org/v4.4.0/dash.all.debug.js"></script>
<script>
  const video = document.getElementsByTagName('video')[0];
  const url = 'https://dash.akamaized.net/dash264/TestCases/1a/sony/SNE_DASH_SD_CASE1A_REVISED.mpd';

  const player = window.dashjs.MediaPlayer().create()

  player.initialize(video, url);
  player.setCustomInitialTrackSelectionFunction(getTrackWithLowestBitrate);
  player.setMute(true);
  player.play();

  document.getElementById('withoutReset').addEventListener('click', () => {
    player.initialize();
    player.setCustomInitialTrackSelectionFunction(getTrackWithLowestBitrate);
    player.attachView(video);
    player.attachSource(url);
    player.play();
  });


  document.getElementById('withReset').addEventListener('click', () => {
    player.reset();
    player.initialize();
    player.setCustomInitialTrackSelectionFunction(getTrackWithLowestBitrate);
    player.attachView(video);
    player.attachSource(url);
    player.play();
  });

  var getTrackWithLowestBitrate = function (trackArr) {
    let min = Infinity;
    let result = [];
    let tmp;

    trackArr.forEach(function (track) {
      tmp = Math.min.apply(Math, track.bitrateList.map(function (obj) {
        return obj.bandwidth;
      }));

      if (tmp < min) {
        min = tmp;
        result = [track];
      }
    });

    return result;
  }


</script>

[dsilhavy]

Thanks for pointing this out. Can you confirm that #3979 fixes your issue?

[vodlogic]

I've re-run the sample test I put together above and the issue no longer occurs and a new stream is loaded

[dsilhavy]

@vodlogic thank you