Feat: Ability to use Audiobookshelf Sessions/ HLS Stream

[fmunkes]

Updated 01/19 14:20 documentation part

This PR introduces the ability to use an HLS stream for audiobooks both audiobooks and podcasts. This allows to have an audiobook to be split among multiple files, as this is effectively hidden from Music Assistant.

Details

• ABS:
  • We can acquire a Session for podcasts or audiobooks in ABS, as long as we provide a unique device id in our Device Info Parameters
  • A transcoding session (that's what we use here) launches an ffmpeg process at ABS providing an HLS stream.
  • ffmpeg process only terminates, when we close the session.
• Implementation:
  • I used the device id approach of the jellyfin provider, and then added the id of the media item the session is for. This allows a session per media item.
  • I added two config options - HLS for podcast, HLS for audiobooks
    • For audiobooks default is true.
    • For podcasts default is false.
  • If a session is need for audiobooks is determined automatically.
  • Schema has been updated for sessions.
  • Logging: I added a couple of debug logging information.
• Advice needed/ open questions:
  • I currently just collect the ids of open sessions in a list[str].
  • I close all open sessions when we shutdown Music Assistant. I figured that's the only safe place to do so.
  • Reasoning:
    • If I were to close the session once on_played is called, a potentially running parallel stream of the same media item to another speaker would terminate as well.
    • Even if that's not the case, I think mass caches the stream details, i.e. get_stream_details would not be called again when the item is replayed.
  • Is the approach in place ok? Is there a better place to close open sessions?
  • Shall I limit the amount of sessions possible, and then maybe raise an error once we hit that limit? I could add another config option for the amount of possible open sessions.
• Possible improvements:
  • We could potentially update the time spent in that session, which would update the ABS statistics view. For me that's very low priority as I don't see an easy way of accessing the time spent (i.e. including possible seeking by user etc, not the media progress!) on that stream.
• Remarks:
  • on_played works nicely now, progress reporting to ABS seems functional.
    Thanks for that!

Documentation update:

If that PR is merged, then:

Known Issues/ Notes:

• Restarting Audiobookshelf terminates all open sessions. Music Assistant has no way to know this, so you must reload the provider. Otherwise the stream of your audiobook will be not available.

[marcelveldt]

Looks good, nice work!

[OzGav]

@fmunkes I have added the note above but does this now mean the existing note about having to merge multi file audiobooks can be removed?

[fmunkes]

@fmunkes I have added the note above but does this now mean the existing note about having to merge multi file audiobooks can be removed?

Yes, that can be remove entirely, thanks!