It all started with a report about federation breaking between Lemmy and NodeBB. I was subconsciously aware that something was going on, but had chalked it up to network issues.

Observed behaviour showed that some remote categories would be receiving content in spurts, with long gaps in between.

I spent the next 3-4 days looking into it, but came up empty. Whatever was happening wasn't throwing any obvious errors, and along the way, I found what I thought was related (it was), but I wasn't sure why: against some Lemmy servers, the "follow"/"unfollow" mechanic would simply stop working, and this would often coincide with gaps in content. In some egregious cases, the flow of content stopped completely!

Unable to make headway, I had to reach out to the folks at Lemmy to figure out what the issue was. NodeBB occasionally sends non-200 level responses depending on the activity. Specifically, the following scenarios:

• A remote user upvoting more than 20 posts in a single day (a spam prevention tactic) causing NodeBB to throw an error, which was caught and returned an HTTP 500 Internal Server Error.
• A Dislike activity, which is not currently handled by NodeBB. In these cases, NodeBB would send an HTTP 501 Not Implemented

When encountering either of these responses, Lemmy would return the activity back to the queue for later delivery and mark a delivery failure. If enough of these (~40) happened within 24 hours, Lemmy would give the instance a time-out and pause delivery completely.

That was it — a quick pair of code updates later, and we started working through Lemmy's backlog of 4.1M activities.

As of 4am this morning, community.nodebb.org is no longer behind lemmy.world.

Fun week. Let's not do that again LOL.

v4.4.2 of NodeBB contains the updated logic for smoother Lemmy federation.

kichae@wanderingadventure.party I'm still at the point where seeing two-way federation working for real between instances is so exciting that it overrides the pain of federation

I'm wondering how content on threadiverse is automatically assigned its community when received by the software (e.g. PieFed, Lemmy, Mbin).

The answer I am expecting is "if the community is addressed (to, cc, audience), then it is slotted into that community".

However that causes issues for compatibility with microblogs... for example, silverpill@mitra.social recently authored a post that mentioned [swf@socialwebfoundation.org](https://community.nodebb.org/category/swf@socialwebfoundation.org) and it got slotted into that community on NodeBB, which isn't correct since that group is private.

Better practice would be to only trust the addressed community if it is Announce'd by the community directly, but would fall short if my instance does not receive the Announce (say, if nobody follows the community), in which case we'd fall back to "uncategorized", which is where all microblog posts currently go. Then it's neither correct nor incorrect, I suppose.

I think this might be an issue where NodeBB tries to be too many things at once (microblog and threadiverse compatible).

Does anybody know what exactly Pleroma needs for a valid Webfinger check? I'm attempting to figure out why @jmtd@pleroma.debian.social won't resolve in NodeBB, and it's because the webfinger call returns 400 Bad Request.

NodeBB is calling https://pleroma.debian.social/.well-known/webfinger?resource=acct%3Ajmtd%40pleroma.debian.social with User-Agent and Content-Type headers (curiously, it's not sending Accept, but it also fails if that header is set, so that's irrelevant.)

Navigating to that webfinger url in the browser returns XML, which is but I'm not even getting that when NodeBB makes the call.

לאצי don't worry about it! You shouldn't have to alter your username just to suit our latin-character world

I would say that Pixelfed is closer to the microblog space than it is the threaded discussion space.

It's essentially microblogging except with an image media focus (or video, in the case of Loops.)

To each their own, some people communicate better using pictures, some better over short text, some better over long-form text. There's a space for them all

Oh, @icaria36@the.socialmusic.network is running Discourse. Well, all bets are off then

@freamon Create(ChatMessage) is not part of ActivityPub. From my light research online it is something added by a Pleroma extension and possibly supported by Lemmy.

NodeBB will automatically slot received non-public notes as chat messages.

@kirk@social.coop just wanted to drop a note that your two issues have not been forgotten

Hey @dansup@mastodon.social, can I poke you about getting NodeBB on FediDB?

It automatically picked up a couple NodeBB sites, so I think the nodeinfo stuff is working, just not sure if it required some manual intervention on your end to get the software link working — it currently 404s.

Cheers

@CWSmith not right now, no. A category can only follow other accounts that identify themselves as "Group". This is to take advantage of synchronization logic that regular users don't supply (and even then not all groups do either).

However I'll keep this workflow in mind, it's an interesting idea!

@frankm@linux-nerds.org this is now done. Turns out I wasn't actually stopping a category from following a user, so that didn't need rolling back.

Ability for categories to follow regular users · Issue #13232 · NodeBB/NodeBB

This was technically already supported (as in, categories could follow regular user accounts), but it did not work consistently. Specifically, if a user was followed by a category, only the content shared by that user was automatically s...

GitHub (github.com)

@hamiller@forum.wedistribute.org using a hashtag is probably also something I should allow categories to follow, although that's local-only to the instance because of how hashtags work.

Either way I didn't want to restrict a valid use case

@Kichae my fear is that adding in the ability for users to customize the forum index with dilute the importance of local categories.

I'm always a big supporter of community building, and while I am very appreciative of the network effects of activitypub, there is the other local community building side that I would want to keep top of mind as well.

silverpill@mitra.social I thought about checking against the outbox, but there's a potential race condition that could occur if I receive the Create(Note) at roughly the same time as the community, but the community hasn't processed the activity yet. In that scenario, the activity would not be in the outbox for checking.

The same thing would happen if there was some out-of-band check for object membership in a collection (not that there is one right now).

I'm assuming Unicode in handles is not allowed? At least by Mastodon.

This user is not able to have their content federated because the username is all Hebrew (I think?) characters!

mro@digitalcourage.social the order of the Hebrew characters is correct, although I believe it should be wrapped in <bdi> tags so the rest of the line isn't affected </bdi>

לאצי the usernames work fine locally (that is, on the site itself). It's when interoperating with other sites not running NodeBB where there are issues, it seems