Pre-Alpha ActivityPub-related bug reports

Scott M. Stolz

@julian Mastodon and other platforms don't understand the concept of threaded conversations, which is why they haven't implemented something like that.

I am not sure how to implement this in ActivityPub, but in the Zot protocol, Hubzilla actually fetches the entire thread from the authoritative source.

So we don't depend on the entire thread being sent to us. We ask for a copy of all of the posts in the thread from the server with the top level post, which arguably is the authoritative version of the thread.

Other servers pushing messages to us is a great way to get notified of new posts, but pulling messages would yield the full conversation.

I am not sure if there is a way to pull in ActivityPub.

Scott M. Stolz

@julian Another thing that Hubzilla does, mostly to remain compatible with platforms that don't understand forums, is have the forum redistribute all of the posts in the thread.

So, when you comment on a post, your app only sends it to the Hubzilla forum, and then the forum looks and sees who is following that thread or who is a member of the forum, and redistributes a copy of the post to everyone who is supposed to get it.

So as long as you are following that thread or are a member of that forum, you get a copy of all of the new messages. (And if you are using Zot protocol, it fetches all of the recent posts when you first follow the forum, which gives you complete threads for recent conversations.)

And one reason why I may be missing some of the posts in this thread is that I am following you (and some others) and not the forum itself.

How do I follow this forum or thread specifically?

julian

@[email protected] said in Pre-Alpha ActivityPub-related bug reports:

I am not sure if there is a way to pull in ActivityPub.

No standard ways, at present, but of course, you can always do an S2S call for the individual objects themselves. The problem is, how do you get the whole thread (which as you mention above, Mastodon can't even support at present). Hell, how do you even get the authoritative source besides traversing up the entire reply chain?

I often feel like I am pushing against the "ActivityPub zeitgeist" of sorts, because I am plainly advocating for a thoughtfully designed pull-based mechanism for backfill purposes, but at least among those I've talked to, I'm not hearing any pushback.

I am not sure how to implement this in ActivityPub, but in the Zot protocol, Hubzilla actually fetches the entire thread from the authoritative source.

In NodeBB, each object references a context, which is an OrderedCollection of other objects. That context is the authoritative source (or at least, as authoritative as NodeBB can determine).

I'm planning a survey on context usage, to see whether other implementors use it at all, and how.

Emelia 👸🏻

@julian I'm maybe not seeing the right post, but on the "duplicate content" issue, if you've an unauthenticated user viewing a federated post or account, the best practice is to provide an intersitual saying “This post wasn't made it, click to view the original post”

This is what it looks like in 4.3 for mastodon: https://github.com/mastodon/mastodon/pull/27792

Emelia 👸🏻

@julian Why? because the unauthenticated user should not be able to view federated content, since this may make you susceptible to public cache poisoning attacks, where a third-party could make you publicly display CSAM content, and then it looks like you're displaying it first-party and hosting CSAM to your hosting company, who takes your server down immediately and/or reports to LEO.

We've already seen this attack used to take down fediverse servers.

Scott M. Stolz

@julian

I often feel like I am pushing against the "ActivityPub zeitgeist" of sorts, because I am plainly advocating for a thoughtfully designed pull-based mechanism for backfill purposes, but at least among those I've talked to, I'm not hearing any pushback.

Hubzilla and Friendica were one of the first platforms to implement forums (or more accurately "discussion groups" although the only difference is the UI). The biggest challenge at the time was that other platforms didn't (and most still don't) understand groups and group discussions.

When developing, they basically used the following tactics:

1. Implement full discussion group features within Hubzilla, and Friendica, respectively. People who use those platforms get the full experience and full feature set.

2. For platforms that don't have the same features, they implemented what they could. If other platforms don't support certain things, that is not our fault. But we still designed it so that it works with their platforms, mostly using workarounds. They could at least participate, even if they didn't get the full experience.

I think we need to take the same approach. We design it so that thread-based platforms (forums, discussion groups, Facebook-style social media, etc.) all can interact with a full set of features. For social media platforms that don't support threaded conversations, we just do "best effort" accepting the fact that their users will have a degraded experience because their software doesn't support the same features.

So, I would recommend that we create some method of backfilling a thread from the authoritative source (using a pull mechanism), and we advertise that this functionality is available via webfinger and as part of the meta data of the posts themselves. Platforms that don't know what that is will ignore it. Platforms that know what that is will use it.

ActivityPub seems to be a push only protocol, so we may need to make our own mini-pull protocol for this purpose. You can look at the Zot protocol that is part of Hubzilla as an example. I think the Nomad protocol that is part of Streams also does the same thing. Not sure about Friendica. But there is working code that already pulls the entire thread.

Scott M. Stolz

@Emelia

@julian

I don't think there really will be a duplicate content issue. Typically, copies of posts are delivered to people's private inbox, not reposted publicly on other websites. Unless someone is operating a relay or reposting other people's posts, all of the copies of the post that are sent over ActivityPub should be private.

Scott M. Stolz

@crazycells Search engines would not see them. ActivityPub basically serves as a notification mechanism, except it delivers the entire post to the follower's private inbox and they can reply back without visiting the forum. Forum posts and comments do not get republished publicly.

Steve Bate

scott:

Search engines would not see them.

This doesn't seem to be true.

The content of Julian's post at https://socialhub.activitypub.rocks/t/hi-julian-i-wonder-how-search-engines-and-seo-will/4135/12?u=stevebate is indexed with both socialhub and nodebb URLs.

Google SERP screenshot:

[email protected]

I received an activity with this ID:

https://community.nodebb.org/post/100125#activity/create/1719328808532#activity/announce/1719328833687

It has two #-signs. I think it is not a valid URI: https://datatracker.ietf.org/doc/html/rfc3986#section-3.5

A fragment identifier component is indicated by the presence of a number sign ("#") character and terminated by the end of the URI.

julian

@[email protected] I see it, thanks for reporting, just pushed a fix, let me know if the IDs still look funky.

cronlabspl

@the-skyfoxx can confirm this behavior.

/cc @julian any fix comming (soon)?

julian

@macfan hi, to which issue were you referring to?

the skyfoxx

@julian said in Pre-Alpha ActivityPub-related bug reports:

@macfan hi, to which issue were you referring to?

I think this one: https://community.nodebb.org/topic/17867/pre-alpha-activitypub-related-bug-reports/13?_=1719346171531

But seems to work for me now

Mariana Terrazas

This post is deleted!

silverpill

@julian The URL of this topic is https://community.nodebb.org/topic/17867/pre-alpha-activitypub-related-bug-reports
When I make a request with AP Accept header, the server responds with a Collection. Technically, this is not wrong, but I think most people would expect a top-level post (Note / Article) when making such request

julian

@[email protected] you're the first person to have noticed!

It's by design, but of course, can — and maybe should — change. It's part of @[email protected]'s FEP-7888 and its concept of a resolvable collection.

Mapping the topic URL to the top post (or perhaps a redirect to it) would ensure compatibility with Mastodon, but I am unsure of whether that is the best path forward.

infinite love ⴳ

@julian @silverpill why would anyone expect a Note/Article when fetching the URL for an entire thread/topic?

Emelia 👸🏻

@trwnh @julian @silverpill I'd only expect a Note/Article when explicitly requesting the first post in a thread/topic, not when fetching the topic itself

julian

@[email protected] @[email protected] that was my thought as well, and why NodeBB currently responds as it does.

Ideally it could be both an Article and a Collection, but now we're really committing to incompatibility there lol

cc @[email protected]