Why is there an actor's `liked` collection but no actor's `shared` collection?

[trwnh]

Question raised per WG readthrough of the spec: https://hedgedoc.socialweb.coop/AePwJKbMQFC7tDsCWY6Pew?both

[nightpool]

because shared activities generally end up in the actor's outbox but liked activities don't, is my understanding.

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[snarfed]

Makes sense. Seems like a shared collection could still be appropriate and useful too though, at least as another MAY.

[trwnh]

What generally ends up in the outbox is the POSTed activities, though... right? If you Announce something by its identifier as a reference, it's no different than if you Like something by a reference. Both of those end up in the outbox (modulo any persistence behaviors of a given outbox). But we only add the Like.object to actor.liked and do nothing with any other activity type...

I guess the more general question is why we don't have a "created" collection, or so on. Why does only the "liked" collection get to be special?

[snarfed]

Agred! Not just liked, but followers and following too.

The most basic argument for shared is consistency. We currently have following and followers, likes and liked, and shares but no shared.

Bigger picture though, I'm not sure I have an opinion yet on which of those should exist, or why, beyond just consistency.

[evanp]

So, I think there's an argument from parallelism (likes and liked implies shares and shared), but I'd like to see an argument from user stories.

Here are my user stories for liked:

• "As an ActivityPub user, I want to have a collection of all the things I have liked, because the things I like are good and I want to review and enjoy them later."
• "As an ActivityPub user, I want to see what someone else has liked, so I can find new things to enjoy."
• "As an ActivityPub user, I want to see what someone else has liked, so I can learn about that other person."

I'm having a hard time making similar user stories for shared, though. Can someone do it? If not, is parallelism sufficiently worth it to define this property?

[trwnh]

I think the same user stories for liked could be used verbatim for other collections like shared with one word swapped:

• "As an ActivityPub user, I want to have a collection of all the things I have shared, because the things I share are good and I want to review and enjoy them later."
• "As an ActivityPub user, I want to see what someone else has shared, so I can find new things to discover."
• "As an ActivityPub user, I want to see what someone else has shared, so I can learn about those other things."

Someone trying to find what you've shared without a shared collection would otherwise have to iterate over your entire outbox and filter for Announce activities to get their object, in the same way that someone trying to find what you've liked without a liked collection would otherwise have to do the same but for Like activities.

The part that I don't understand is why "liking" gets special privileges above any other social interaction. My assumption is that the liked collection is roughly intended to mirror the "Liked posts" tab on people's profiles in some social media services? But because these services don't expose a similar "shares" tab, I assume that the work stopped there.

For software with more powerful query support, it's less of an issue:

SELECT
  ?object
WHERE {
  </outbox> as:first*/as:next*/as:items ?activity.
  ?activity a as:Like.
  ?activity as:object ?object.
}

I think it makes sense to have other collections for consumers that don't have these capabilities or don't want to make use of these capabilities, though.