Get-stream: Activity propagation via 2 follow relations?

Question

Situation:

• Imagine two models: Songs and Playlists
• You can add reactions (verbs, e.g. "like", "dislike", etc.) only to Songs.
• Each Song lists its aggregated verbs, e.g. 2 users liked the Song, 4 disliked it.
• I set up two feed groups: Song_flat (flat) and Song_aggregated (aggregated)
• Verbs are added to Song_flat while Song_aggregated follows Song_flat.
• So far that works fine incl. realtime updates.

Challenge:

• Playlists should display an aggregated view (again by verb) across all the Songs in this Playlist.
• I set up two feed groups: Playlist_flat (flat) and Playlist_aggregated (aggregated)
• Playlist_flat follows all of the Song_flat feeds associated to it. Playlist_aggregated follows Playlist_flat.
• So in total: Playlist_aggregated follows Playlist_flat follows lots of Song_flat feeds.
• I need the intermediate Playlist_flat feed in order to consume real time updates of all the Song_flat changes which the Playlist_aggregated feed cannot provide.
• Issue: While Playlist_flat lists the verbs added to its songs immediately, Playlist_aggregated does not contain any verbs despite Playlist_aggregated following Playlist_flat.

Questions:

• Is it an error in getstream or are verbs not propagated via 2 link followerships?
• So, must I require Playlist_aggregated to follow directly the Song_flat feeds and NOT via Playlist_flat?

Thank you. Manuel

Answer 1

Feed updates are propagated to followers only to direct followers; 2nd or higher degree follower feeds (eg. follower of a follower) are not supported. My suggestion is to let an aggregate playlist follow each song (or add activities to the song feed and target the playlist with the to targeting field)