Increase playlist stuck target duration coefficient and catch BehindLiveWindowExceptions properly

[AudricV]

What is it?

• Bugfix (user facing)

Description of the changes in your PR

Set a bigger delay before throwing a PlaylistStuckException (15 * TARGET_DURATION_OF_A_SEGMENT) than ExoPlayer's delay (3.5 * TARGET_DURATION_OF_A_SEGMENT), to improve streaming experience on livestreams.

Indeed, I noticed that sometimes, YouTube HLS manifests of livestreams are being stuck sometimes randomly, for a few seconds, and sometimes very frequently (I don't know if that's a YouTube throttling or not), where livestreams on the website/biggest official clients are playing mostly fine. For low or ultralow latency livestreams, this stucking results right now in a exception which is thrown very quickly (sometimes after 1 or 2 second), which makes the livestream unplayable.

This PR also fixes a bug when ExoPlayer encounter a BehindLiveWindowException: the play queue manager was reloaded to try to reload the stream and then an error was thrown. It makes no sense to do this, so this PR makes the player seek instead to the default position, preparing again ExoPlayer (like recommended by ExoPlayer's website) and don't throw an error.

Fixes the following issue(s)

No issue I found was opened for these bugs.

APK testing

The APK can be found by going to the "Checks" tab below the title. On the left pane, click on "CI", scroll down to "artifacts" and click "app" to download the zip file which contains the debug APK of this PR.

Due diligence

• I read the contribution guidelines.

[Redirion]

generally this looks good to me but we need to keep track of those "copy" classes somewhere. In the event that ExoPlayer gets updated we would also have to check if have to update / replace / remove these copy classes as well.

[AudricV]

Yes, unfortunately, that's the only disadvantage of this, but I don't think we have a choice if we want to improve ExoPlayer's default behavior.

[litetex]

I also currently don't like the PR as it introduces a bunch of copy-paste code... jada jada see above comments

Wouldn't it be better if we implement the change into ExoPlayer directly / open a PR by them?
The PR could either

• make all methods / fields protected so that they can be overridden (by us) or
• add an option for the MAXIMUM_PLAYLIST_STUCK_DURATION_MS or something similar

We could also fork Exoplayer and build a custom version with the fix. However that might be to complex (e.g. the building part).

Fun Fact: // TODO: Allow customization of stuck playlists handling. is already inside the ExoPlayer code 😆

[opusforlife2]

Wouldn't it be better if we implement the change into ExoPlayer directly / open a PR by them?

Let's please do this. It will be ironic and hilarious.

[Redirion]

what I just noticed: it should already be customizable. See this commit:
google/ExoPlayer@28434cf

[AudricV]

Yes, but we need to pass an HlsMediaSource.Factory. The only problem is that the factory uses the constructor with the default playlist stuck target duration coefficient value. So what I should do?

[litetex]

Yes, but we need to pass an HlsMediaSource.Factory. The only problem is that the factory uses the constructor with the default playlist stuck target duration coefficient value. So what I should do?

Uhm I don't see a problem here:

--- a/app/src/main/java/org/schabi/newpipe/player/helper/PlayerDataSource.java
+++ b/app/src/main/java/org/schabi/newpipe/player/helper/PlayerDataSource.java
@@ -8,12 +8,17 @@ import com.google.android.exoplayer2.source.ProgressiveMediaSource;
 import com.google.android.exoplayer2.source.SingleSampleMediaSource;
 import com.google.android.exoplayer2.source.dash.DashMediaSource;
 import com.google.android.exoplayer2.source.dash.DefaultDashChunkSource;
+import com.google.android.exoplayer2.source.hls.HlsDataSourceFactory;
 import com.google.android.exoplayer2.source.hls.HlsMediaSource;
+import com.google.android.exoplayer2.source.hls.playlist.DefaultHlsPlaylistTracker;
+import com.google.android.exoplayer2.source.hls.playlist.HlsPlaylistParserFactory;
+import com.google.android.exoplayer2.source.hls.playlist.HlsPlaylistTracker;
 import com.google.android.exoplayer2.source.smoothstreaming.DefaultSsChunkSource;
 import com.google.android.exoplayer2.source.smoothstreaming.SsMediaSource;
 import com.google.android.exoplayer2.upstream.DataSource;
 import com.google.android.exoplayer2.upstream.DefaultDataSourceFactory;
 import com.google.android.exoplayer2.upstream.DefaultLoadErrorHandlingPolicy;
+import com.google.android.exoplayer2.upstream.LoadErrorHandlingPolicy;
 import com.google.android.exoplayer2.upstream.TransferListener;

 public class PlayerDataSource {
@@ -45,7 +50,16 @@ public class PlayerDataSource {
         return new HlsMediaSource.Factory(cachelessDataSourceFactory)
                 .setAllowChunklessPreparation(true)
                 .setLoadErrorHandlingPolicy(
-                        new DefaultLoadErrorHandlingPolicy(MANIFEST_MINIMUM_RETRY));
+                        new DefaultLoadErrorHandlingPolicy(MANIFEST_MINIMUM_RETRY))
+                .setPlaylistTrackerFactory(
+                        (dataSourceFactory, loadErrorHandlingPolicy, playlistParserFactory) ->
+                            new DefaultHlsPlaylistTracker(
+                                    dataSourceFactory,
+                                    loadErrorHandlingPolicy,
+                                    playlistParserFactory,
+                                    /* playlistStuckTargetDurationCoefficient */ 10.0
+                            )
+                        );
     }

     public DashMediaSource.Factory getLiveDashMediaSourceFactory() {

[litetex]

Almost perfect

[opusforlife2]

Importing database into this APK is causing it to close at the splash screen without crashing. This isn't happening on other PR APKs.

Edit: It's happening on all the 3 APKs I downloaded just now: seamless switching, livestream quality selector, and this. Maybe a bug slipped into the dev branch?

[AudricV]

See #7674. I just need to rebase all my PRs.

[Stypox]

I don't have anything to add, code looks good, the comment by litetex just needs to be solved :-)

[sonarcloud]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

0.0% Coverage
0.0% Duplication

[litetex]

Code LGTM

Watched some livestreams for a few minutes and everything worked fine 😄