Subarr

“Sonarr for YouTube” – a tool to periodically check various YouTube playlists and take actions when new videos are posted

Subarr is a lightweight YouTube channel/playlist/subscription follower that will take action on new uploads (actions can be a webhook – like Discord – or a process – like downloading through yt-dlp).

This is an attempt to create a Sonarr-like application for YouTube videos. A lot of inspiration has been taken from Sonarr (mostly the UI), but this has been written entirely from scratch.

Sonarr is based on RSS feeds – explicitly designed for this purpose of getting new updates from subscription-like sources. This is much lighter in processing requirements. I’ve also tried to make this UI as similar as possible to the other *arr apps for familiarity.

What are the limitations of the RSS feed approach?

YouTube already provides RSS feeds for playlists (eg https://www.youtube.com/feeds/videos.xml?playlist_id=PLopY4n17t8RDoFQPcjBKWDEblGH1sOH2h). However, they can be severly limited:

• Feeds seem to be limited to only the last 15 items
  • However, Subarr will list more items as they are found because the internal database will be updated
  • Since the feed is limited to only the last 15 items, if (for some reason) Subarr is down for an extended period of time (or a large amount of videos are published to the playlist in a short period of time), Subarr may miss some videos entirely.
• YouTube RSS feed items are always in “playlist order”, meaning a new video added outside of the first 15 items will not be seen as an update to the RSS feed
  • This means that, currently, RSS feeds will not work in the following situations: (issue logged with YouTube: https://issuetracker.google.com/issues/429563457)
    • YouTube playlists greater than 15 items where items are added outside the “top 15” (regular playlists can be in any order – as determined by the playlist owner – which means that “newly added items” aren’t necessarily at the top. Some creators’ playlists are ordered oldest -> newest)
    • >=15 items added to a playlist quickly (eg if a playlist has 1 item, then when it updates 15 minutes later it has 20 items, 4 of those items will be missed because only the top 15 will be in the RSS feed)
• RSS feeds may be somewhat slow to update (updates are approximately every 15 minutes). 15 minutes is pretty fast, but other methods (like the direct YouTube API – or perhaps even TubeSync’s yt-dl method) could check for new videos even faster
• [May not be a big deal] RSS feeds will not include “Members Only” items