A high-level framework for [ActivityPub](https://www.w3.org/TR/activitypub/) federation in Rust, extracted from [Lemmy](https://join-lemmy.org/). The goal is that this library can take care of almost everything related to federation for different projects. For now it is still far away from that goal, and has many rough edges that need to be smoothed.
- Data structures for federation are defined by the user, not the library. This gives you maximal flexibility, and lets you accept only messages which your code can handle. Others are rejected automatically during deserialization.
To get started, have a look at the example. If anything is unclear, please open an issue for clarification. You can also look at [Lemmy code](https://github.com/LemmyNet/lemmy/tree/main/crates/apub) for a more advanced implementation.
- **Simplify generics**: The library uses a lot of generic parameters, where clauses and associated types. It should be possible to simplify them.
- **Improve macro**: The macro is implemented very badly and doesn't have any error handling.
- **Generate HTTP endpoints**: It would be possible to generate HTTP endpoints automatically for each actor.
- **Support for other web frameworks**: Can be implemented using feature flags if other projects require it.
- **Signed fetch**: JSON can only be fetched by authenticated actors, which means that fetches from blocked instances can also be blocked. In combination with the previous point, this could be handled entirely in the library.
- **Helpers for testing**: Lemmy has a pretty useful test suite which (de)serializes json from other projects, to ensure that federation remains compatible. Helpers for this could be added to the library.
- **[Webfinger](https://datatracker.ietf.org/doc/html/rfc7033) support**: Not part of the Activitypub standard, but often used together for user discovery.
- **Remove request_counter from API**: It should be handled internally and not exposed. Maybe as part of `Data` struct.
