Introduction
The Old Dog and Duck
A Clojure library designed to implement the ActivityPub protocol, obviously.
The Old Dog and Duck is clearly a pub, and it’s a pub related to an activity; to whit, hunting ducks with dogs. Yes, of course one could also hunt dogs with ducks, but in practice that doesn’t work so well. The point isn’t whether or not I approve of hunting ducks with dogs (or vice versa); to be clear, I don’t. The point is that it’s a pub related to an activity, and is therefore an ActivityPub.
Are we clear?
Good.
Let us proceed.
The Old Dog and Duck is intended to be a set of libraries to enable people to build stuff which interacts with ActivityPub. It isn’t intended to be a replacement for, or clone of, Mastodon. I do think I might implement my own ActivityPub server on top of The Old Dog and Duck, that specifically might allow for user-pluggable feed-sorting algorithms and with my own user interface/user experience take, but that project is not (yet, at any rate) this project.
Status
This is a long way pre-alpha. Everything will change. Feel free to play, but do so at your own risk. Contributions welcome.
Architecture
There are a number of separate concerns required to implement ActivityPub. They include
- Parsing ActivityStreams messages received from peers and from clients;
- Persisting ActivityStreams objects;
- Delivering ActivityStreams objects to peers;
- Delivering ActivityStreams objects to clients.
NOTE THAT what Mastodon delivers to clients is not actually in ActivityStreams format; this seems to be an ad-hoc hack that’s just never been fixed and has therefore become a de-facto standard for communication between ActivityPub hosts and their clients.
My proposal would be to deliver exactly the same ActivityStreams format to my client as to other servers. There may be a valid reason for not doing this, but if there is I will discover it in due course.
Proposed dog-and-duck libraries
NOTE THAT at the present stage all the proposed libraries are in one package, namely this package, but that it is proposed that in future they will form separate libraries in separate packages.
Bar
Where conversations happen. Handle interactions with clients.
Cellar
Where things are stored. Persistance for ActivityStreams objects; I may at least initially simply copy the Mastodon postgres schema, but equally I may not.
Pantry
Where deliveries are ordered and arrive; and from where deliveries onwards are despatched. Handle interactions with peers.
Quack
Duck-typing for ActivityStreams objects.
As of version 0.1.0, this is substantially the only part that is yet at all useful, and it is still a long way from finished or robust.
Scratch
What the dog does when bored. Essentially, a place where I can learn how to make this stuff work, but perhaps eventually an ActivityPub server in its own right.
Usage
At present, only the duck-typing functions work. To play with them, use
(require '[dog-and-duck.quack.quack :as q])
Testing
Prior to testing, you should clone activitystreams-test-documents into the resources directory. You can then test with
lein test
License
Copyright © Simon Brooke, 2022.
This program and the accompanying materials are made available under the terms of the GNU General Public License as published by the Free Software Foundation, either version 2 of the License, or (at your option) any later version.