steve

steve, 7 months ago to fediverse

The AS2 specification used by #ActivityPub requires standard JSON-LD compaction so messages can be processed as plain JSON. However, the standard compaction algorithm can be configured in various ways. For example, compactArrays can be configured to false. Is an AP implementation expected to handle the results of all combinations of JSON-LD compaction options?
/cc @evan

steve, 2 months ago to fediverse

If you were measuring performance of #ActivityPub servers (let’s say, delivery latency under load and active user scalability, to start) how would you propose doing it? What else would you measure? Are there any existing benchmarks?

steve, 4 months ago to fediverse

#ActivityPub developers... do you implement an actor (or actors) that provide server-level functionality other than resource fetching or a relay endpoint? Can they be followed? Do they process incoming activities? Is discovery of those actor URIs required by other servers? If so, what are the use cases?

steve, 8 months ago to fediverse

Have you ever wondered how #ActivityPub got its name and what other names were considered? Here's the transcript from the W3C meeting where the naming happened. https://www.w3.org/wiki/Socialwg/2016-01-12-minutes

steve, 1 year ago to fediverse

While doing some Fediverse exploration, I ran across two very interesting (to me) server-side applications of #ActivityPub with live instances. One is https://castling.club/ that facilitates chess challenges and game play. The other is Transit Fedilerts (https://transit.alerts.social/) that "fetches service alerts from transit agencies and publishes them via ActivityPub". It's great to see creative ideas like these being implemented.

steve, 8 months ago to random

I can create Mastodon timelines for sets/lists of accounts and I can create timelines for hashtags. I wish I could make a timeline combining the two (possibly even with nested, publicly-shareable lists).

steve, 8 months ago to fediverse

Other than "Linked Data Event Streams", does anybody know of applications using Activity Streams 2.0 without #ActivityPub?

steve, 3 months ago to fediverse

If the #ActivityPub community effort to define problem domain-specific AP interop profiles proceeds past the discussion phase, some initial profile candidates are: microblogging, video sharing, image sharing, audio/music sharing, media review (books, movies, etc.), and event planning. Each of these has existing implementations and represents a specific AP use case. In the longer term, other profiles, like for forge federation, could be added as implementations evolve and mature.

steve, 6 months ago to fediverse

For the JSON-LD experts out there... does the Compaction algorithm ever produce a document with a null property value in the document body? I know that a null-valued property is treated as if it doesn't exist, but I can't identify the step in the Compaction algo where they are removed (given a null in the pre-compacted document). JSON-LD Playground removes the nulls, but I don't know if this is the normative behavior for all processors or not. #json-ld #activitypub

steve, 7 months ago to random

@evan @jasnell Why are empty arrays not allowed in Activity Streams 2.0?

steve, 10 months ago to fediverse

Does anybody really implement pure #ActivityPub (and ActivityStreams 2)? Looking at the actor (and/or attributedTo) fields, for example. There can be multiple of each. The JSON representing them could have a string/URI, a mapping, a Link, or a list of a combination of those types. Assuming a server handles all those variations (I doubt any server does), how does it interpret it in a context where a specific inbox/outbox POST is authenticated using HTTP signatures (single actor)?

steve, 8 months ago to fediverse

I've started collecting my web bookmarks in a self-hosted instance of Postmarks, an #activitypub enabled bookmark manager. I've customized it with a dark mode and Docker support. Fun!

https://bookmarks.stevebate.dev/

https://github.com/ckolderup/postmarks

steve, 2 months ago to fediverse

Given it also applies to #ActivityPub, can someone explain the following “ActivityStreams 2.0” requirements? (Section 2.2) “(1) when an IRI that is not also a URI is given for dereferencing, it must be mapped to a URI using the steps in Section 3.1 of [RFC3987] and (2) when an IRI is serving as an "id" value, it must not be so mapped.” Isn’t an IRI given for dereferencing always an IRI serving as an “id” value for some Object? Maybe some examples would help to clarify it?

steve, 7 months ago to fediverse

Is anybody aware of the #ActivityPub actor “streams” property being used in an implementation?

steve, 9 months ago to fediverse

@bengo Have you had any thoughts about how to represent "conditional MUST" behaviors in the #ActivityPub specification? Also, as a side note, it's great that you are including JSON-LD contexts in the behavior YAML files. This will be useful for combining the behavior data with other RDF data sets.

steve, 1 year ago to fediverse

What is the best, most feature-rich, #ActivityPub C2S client (not server) implementation currently available?

steve, 1 year ago to fediverse

So, I start a new under-development #ActivityPub server and try to (unsuccessfully) Follow from my self-hosted Mastodon instance. Within an hour, multiple Fedi-crawlers are probing the experimental server endpoint. Are they querying my Mastodon instance for known hosts or is there another way they are finding this new experimental server so quickly?

steve, 6 months ago to fediverse

It can be difficult to understand the role of JSON-LD in #ActivityPub. I see criticisms that are based on the belief that JSON-LD is a schema language or a validation tool. It's not. It's an RDF serialization. There's a good online book, "Validating RDF" that discusses several tools (including JSON Schema) that can be used to constrain message shapes (define schema) and do validation based on those constraints.
http://book.validatingrdf.com/index.html

steve, 5 months ago to fediverse

#ActivityPub dev tip of the day: An inbox (or outbox) is not a queue. An inbox is reverse chronological (LIFO-ish) and maintains long-term references to items. A queue has FIFO behavior and items are dequeued/removed for processing. AP is difficult enough without equating the inbox concept with MQ middleware (which could be a useful internal implementation technique).

steve, 5 months ago to fediverse

One of the challenges with #ActivityPub targeting is that the targeting properties (to, cc, bto, bcc, and maybe audience) conflate inbox delivery, interaction authorization, notification policies, and visibility (and probably more). This is a broad range of somewhat orthogonal behaviors and the limited guidance in the specs for them only makes it more challenging for AP devs.

steve, 4 months ago to fediverse

I often see the "Robustness Principle" invoked when discussing ways to improve #ActivityPub interop. There's an IETF draft that discusses the negative consequences of this strategy. Instead, they suggest that "A community that takes an active role in the maintenance of protocols will no longer need to rely on the robustness principle to avoid interoperability issues." Sounds great to me.
https://intarchboard.github.io/draft-protocol-maintenance/draft-iab-protocol-maintenance.html#name-harmful-consequences-of-tol

steve, 4 months ago to fediverse

The #ActivityPub sharedinbox is a strange concept. It's an inbox without an actor. I suppose one could think of it as being backed by an implicit, non-conformant (no outbox) actor-ish thing that routes messages to other inboxes. There's no requirement that there's zero or one sharedInbox per server. A server can have any number of them. You could have one per set of actors in a Group or Organization, for example. But then the sharedInbox would an Group/Org actor-specific inbox. 🤯

steve, 3 months ago to fediverse

@helge It looks like your Fun Fediverse support tables are currently focused on microblogging implementations. Do you plan to expand that to other federated solution domains? If so, I recommend taking a look at FunkWhale's #ActivityPub implementation. It's different than the classic microblogging use case in several interesting ways.

steve, 3 months ago to fediverse

I’m beginning to wonder if the email mental model some people suggest for #ActivityPub is a serious hindrance to understanding the concept of a federated, decentralized social graph.

steve, 3 months ago to fediverse

According to Federated SNS history, first there was the "identiverse", then there was the "fediverse". And, of course, there's the "metaverse". Now there is the "agentverse"??? The latter reminds me of the actor(à la Carl Hewitt)/agent-oriented vision of #ActivityPub I sometimes see discussed, only blockchain-based. 🤔
https://fetch.ai/docs/concepts/agent-services/agentverse-intro