It works but it’s not the most pretty thing in the world. @franzliedke
Would be great if you could take a look at the whole formatting API and
work your magic on it sometime… my brain is fried!
Originally the user activity feed was implemented using UNIONs. I was
looking at make an API to add activity “sources”, or extra UNION
queries (select from posts, mentions, etc.) but quickly realised that
this is too slow and there’s no way to make it scale.
So I’ve implemented an API which is very similar to how notifications
work (see previous commit). The `activity` table is an aggregation of
stuff that happens, and it’s kept in sync by an ActivitySyncer which is
used whenever a post it created/edited/deleted, a user is
mentioned/unmentioned, etc.
Again, the API is very simple (see Core\Activity\PostedActivity +
Core\Handlers\Events\UserActivitySyncer)
Perhaps also in user activity stream. They are used in the mentions
extension.
In order to generate the excerpt, each formatter can implement a
“strip” method which basically converts block formatting into inline
formatting.
