I think the #ActivityPub client-to-server API is extremely important and underrated.

@evan @steve

It is both, like in that diagram draft.. or at least could be considered such (the notes apply to Protosocial musings).

https://social.coop/@smallcircles/116099511464629495

@mariusor I have implemented it requiring OAuth on one side and using HTTP Signature on the other. I think you need to use the user's authorization for private content or to respect personal blocks. It sucks for caching but ¯\_(ツ)_/¯

@thisismissem @benpate @steve @smallcircles

@evan yes, that's how I did it too, only in my case the private key of the actor that is authorized by OAuth2 token is used to generate the signature for the proxy fetch. This makes it that servers that implement object ACLs based on the recipients list (which GoActivityPub servers are) are not serving 403s for fetches.

Yeah, this is how I'd expect it to work (with the possible addition of *also* allowing cookie auth on the client side)

But yeah. Locally authenticated user from my client -> my server, then HTTP signature from my server -> your server

@evan @mariusor @thisismissem @steve @smallcircles

@deadsuperhero so, it's a two-sided market -- clients and servers. The traditional mechanism is a "ratchet" -- build up one side, then build up the other, and then build up the first.

So, yes, servers first, then clients, then more servers, more clients, and so on back and forth.

@benpate

With all the standard warnings around proxies!

@mariusor @thisismissem @steve @smallcircles

@smallcircles @steve @mariusor

I think in particular the terms "publisher" and "consumer" from AS2 and "client" and "server" from AP don't always map cleanly, especially with HTTP POST requests.

When a client delivers an activity to the actor's outbox, the client is the publisher of that activity, and the server is the consumer.

Same when a sending server (publisher) delivers an activity to a receiving server (consumer).

@evan @mariusor @benpate @steve @smallcircles yeah, it's the only way to do it.

But this infrastructure actually is what enables things like the AT Protocol "proxy through my PDS to the bluesky app view" or "proxy through my PDS to a custom feed generator" functionality.

That's how that all works.

@evan @steve

Another issue: Unclear protocol layers.

> I am not a fan of the idea that #ActivityPub is a message-passing system; it's a read-write API.

I'm not sure what a "read-write API" is, really. It 's a fuzzy term, whereas message based systems have well-defined architecture patterns and a body of IT knowledge and practice to apply them in robust communication systems. A 'Message API' has a generic, consistent interface.

The overarching goal of AS/AP should be empowerment of the Solution developer so they can directly focus on building use cases for their application or business domain. They should not have to think about any of the intrinsics of the protocol, like particular GETs and POSTs used to model protocol capabilities in the HTTP transport layer.

Solution design then involves:

0. Model the domain
1. Data modeling, msg formats + validation
2. Define actor msg exchange patterns
3. Document design
--
4. Improve these steps. Add native protocol + tool support over time.

@smallcircles @steve it's ok if you haven't heard of a REST API. It's an API that uses HTTP for reading and writing data. Wikipedia has a good
article about it:

https://en.wikipedia.org/wiki/REST

@smallcircles @steve one anti-pattern I dislike seeing in ActivityPub discussions is that only one interaction defined in the ActivityPub spec is valid: an HTTP POST to an actor's `inbox` for server-to-server interactions.

We can use HTTP GET to fetch additional data about objects, actors and collections.

@smallcircles @steve So, I disagree that we have to exclusively adopt a message-passing paradigm for ActivityPub.

EDIT: note that it's exclusive.

@evan @smallcircles @steve ActivityPub already is a message passing paradigm

@evan

> it's ok if you haven't heard of a REST API.

Well, you be you. I consider this a 'typical Evan remark' by now, dripping with sarcasm. It is a weird fit for someone who want to lead the #SocialCG efforts, I'd say.

Ah well. What I am talking about is architecture and design, and all the things that allow people to easily form a clear mental picture on how things fit together, wrap their head around the fediverse.

A HTTP interface is a very low-level thing, and clearly but one of the many moving parts that play a role in #ActivityPub based solution development.

Never defining this well, and having the documentation be scattered all across the fediverse in 1,001 random locations doesn't help. Meanwhile the dev talk that is going on for years remains very inefficient due to endless Babylonian speech confusion.

https://social.coop/@smallcircles/116109447243110037

@cwebber @steve

@smallcircles @cwebber @steve hey, Arnold.

I don't think argument from ignorance is a good way to have a discussion.

I chose to take you at your word that you didn't know what a "read-write API" is, and that you couldn't figure it out from context clues, so I dropped a link to Wikipedia.

What would you have done, if you were me?

@cwebber @smallcircles @steve thanks for that important clarification.

It does use message-passing, but not exclusively. I'll update my reply.

@evan @cwebber @steve

Which was exactly what I also indicated above, and which aligns to that diagram as well.

@evan @cwebber @steve

So why don't you use the word REST? I never encountered "read-write API". It is an informal term.

But that is not the point. You can have a REST API, fine. But that says nothing in itself. What does it expose? You might say "Duh.. ActivityPub!" but that is not very informative either. There is the notion of message exchange, and of an addressing mechanism, indicating higher level abstractions that conform to well-known architecture patterns, and would allow us to have more productive communication, delve less in implementation details and confusions of protocol behavior with solution design functionality, for starters.

@smallcircles @cwebber @steve awesome.

So, would you like me to review your diagram and give comments? I don't know what you're looking for from me in this conversation.

@evan @cwebber @steve

Not needed. I hope to be able to add some feedback to the AP API repo.