Youtube transcripts import doesn't work

[dyudyunov]

Expected Behavior

Transcripts are automatically fetched.

Actual Behavior

Transcripts are not available.

Steps to Reproduce the Problem

1. Create a video unit;
2. Add a video URL for video that has transcripts (e.g. https://www.youtube.com/watch?v=3_yD_cEKoCk);
3. Check the transcripts section of the video-xblock advanced settings.

Specifications

• Version: v1.0.2
• Platform: Lilac

Notes

• https://video.google.com/timedtext?lang={lang_code}&v={video_id} (fetch transcript) and video.google.com/timedtext?type=list&v={video_id} (list available to get name if any) -- always returns 200 and empty response
• I've not found any documentation or changes description for the API
• I've found that API stopped working as it was starting from November 2021
• As described here, google doesn't support API used by video block transcripts
• Looks like transcripts upload functionality should be updated to use the actual documented Youtube API https://developers.google.com/youtube/v3/docs/captions
  The problems we'll face in this case:
• This API requires auth (api_key is enough)
• It returns JSON response (current implementation expects XML)
• Don't know what the docs telling about when saying Quota impact: A call to this method has a quota cost of 200 units.

[throwaway-a]

FWIW we have classes that have upwards of 90 videos, and this completely murders our sysadmins that after we get new transcripts back, they have to upload it to two places. If this were fixed, then they could just upload to YouTube and pull into Open edX like they used to do before Lilac. So I'm hoping this can be fixed by the M release next December...