Use ActivityPub for federation

[drequivalent]

We now have a standard for federated interaction between services, called ActivityPub:
https://www.w3.org/blog/news/archives/6785
https://activitypub.rocks/

We already have Mastodon, Pleroma and PeerTube in our Fediverse. Soon there will also be Aardwolf and several other social interaction engines. It would be cool if you join in.

[mshayden]

I have been tinkering with the concept of an ActivityPub library or "engine" using Python with Celery (which would play the role Sidekiq does in Mastodon). I should revisit this work and perhaps see if it could be applied here.

[mhall119]

I would like to get ActivityPub suppoet added, I've been hoping someone would come along who knew how to implement it!

[strypey]

Are you familiar with SocialHome? They are one of the federated social network apps using the Diaspora protocol, also developed in Python/ Django. Perhaps the developers of SocialHome and GetTogether could collaborate on figuring out what existing Python/ Django code there is for exchanging event data across federated networks using standardized protocols?

Both Friendi.ca and Hubzilla have events calendar features, and since they're close cousins, I'm guessing they've at least done some scoping work on federated exchange of events data across apps that could shine some light on possible solutions. NextCloud and ownCloud also have events calendars, and I believe the former (and possibly the latter) is implementing ActivityPub internally for federation between its own instances, so it might be worth talking to them as well.

Finally, Upcoming.org is another events site using a free code engine, and while I don't know if they have any interest in federation, it could be worth reaching out to them too.

[jaywink]

Thanks @strypey for the ping, GetTogether looks awesome, will be keeping a look.

Regarding federation. I really recommend going with ActivityPub. It has good support for events in the standard vocab and supports extensions where support runs out and has recently picked up steam with many projects either implemented or planning to implement. It's the first federation protocol for the social web that is starting to feel like a standard, even though it's still early days.

For Socialhome (which has events planned in a more Facebook kind of way), ActivityPub support will arrive via my federation library, which currently supports Diaspora protocol. The idea is to have a library that supports multiple protocols over one unified API, so it's a bit opinionated, not a direct 1-1 mapping of the protocol. If interested to have a look, and maybe even collaborate, it's here. I plan to work on activitypub for the library within the spring / early summer, by current timetable.

[mhall119]

Initial ActivityPub work is live here: https://gettogether.community/activity_pub/events.json

[mhall119]

Can somebody please comment with what more needs to be done before closing this issue?

[craigmaloney]

I'm not sure how to use this in the context of other sites. It only seems to be a large feed of all of the events, not something where each team / location can broadcast what's going in there.

[zcdunn]

@mhall119 you'll need to implement webfinger so other fediverse implementations can look up Actors (Person, Group, etc). It's not technically part of the spec, but most implementations require it.

When a user/team creates a new event, you'll need to put an Event object in the Actor's outbox, wrapped in a Create Activity.

[DeadSuperHero]

It probably also wouldn't hurt to test against other ActivityPub players in the space. The main ones of importance with working implementations are:

• Mastodon
• Pleroma
• MissKey
• Hubzilla

Basically none of those support an Event activity specifically, but it should be possible to generate some kind of fallback note activity that each of these things can see.

[Briar503]

@mhall119 would you mind if I took a stab at this? I'm not a "federation expert" but I think I can work this out given a bit of time. With a milestone of 1.0.0 I imagine I can get it done with lots of time for review.

[mhall119]

Go for it!
The two relevant specs are ActivityPub and ActivityStreams