Re-using this topic as it is still open. I’m currently implementing FEP-400e from @grishka, in order to provide a complete project-agnostic groups implementation covering every known groups implementation and quirk (there are a fair number of these and I suspect we’ll have even more before all is said and done). Some questions came up.
If an actor has publicly-appendable collections, its server MAY include them as additional fields in its ActivityPub representation. For example, user actors may specify the link to their walls, or groups may specify the link to the collection of their photo albums.
Implementations MAY use the presence or absence of specific collection to determine whether the actor’s server supports features that depend on that collection and alter their UIs accordingly.
What is the proposal for indicating these writable collections in the actor record? It’s OK if this is just a hack. I just need to know what it is so we can use it and alter our behaviour accordingly. I’m more concerned at the moment with the “wall” than photo albums, but if there’s an example actor record that shows what is planned for both it would be sweet.
The next question is about using Create/Note/Collection (type, object,target). In the original AP/AS specifications, it was suggested that such activities should be Add/Note/Collection (not explicitly, but more or less inferred in the description of ‘Add’ and also the text in section 5.8.2 “Collection Management”). I intend to provide this as a general collection management interface and as recommended in the spec. Is there any chance that Smithereen could also do this, or should we also support Create/Note/Collection purely for Smithereen compatibility?
Third question. Regardless of the answer to the second question, there are different behaviours depending on the audience of the activity. If the activity is public, we don’t intend to add the Note to the wall (technically the outbox). This is more a published report of an activity that already happened - “Joe added a note to the Foobar group’s outbox”. Whereas if there is a single recipient (the owner of the wall) it can be taken as a directive to actually perform the activity rather than just report that it happened. Not sure how best to clarify this difference other than by looking at the audience and seeing if the collection belongs to the single recipient and ignore it if the activity is addressed more widely.
Fourth question (slightly related to the third): If the collection operation fails (lack of permission), is it even appropriate to notify anybody else besides the wall owner of the collection operation? I would say no, but I know there are a lot of people in this forum that would disagree and say the actor should be able to tell anybody anything at all, and the success or failure of the operation isn’t relevant. Because free speech. But if the activity is “Joe added a note to foobar group’s outbox” and it didn’t actually get added to foobar group’s outbox because Joe isn’t a member, such an activity is a lie and should not be sent.
I’m merely suggesting that any kind of activity with a collection target might require a bit of extra care to define the activity audience; which would let receivers know for certain whether this was a request to perform the operation or an activity reporting that it happened. Without looking at the activity audience, the desired action on receipt of the activity is ambiguous.