Nothing posted from outside Fedia federates out

dannekrose, 9 months ago

@chris

This is by design. ActivityPub is a push model and it's a Push-once (in general).

What that means is that the instance that the creator/author of the content is on will push the content to all the other instances that it knows are subscribers to the "account/magazine" that the content is being pushed to.

What that means is:

• Feddit.uk will push the content to Feddia.io because that's the "destination" account/magazine.
• Feddit.uk will push the content to any instances that is also happens to know subscribe to the magazine "ukdtt"
• Fedia.io will not re-push the content to all the instances that subscribe. That's the responsibility of the instance that the content "originated" from, not Fedia.io

e569668, 9 months ago (edited 9 months ago)

This is something I have been wondering; but does that mean kbin/this instance is not involved at all?

For the post in question, the original url is https://feddit.uk/post/771973 , a lemmy instance. OP is asking why it isn't getting sent to rabbitea.rs, another lemmy instance. Is feddit.uk responsible for sending it there? But how would it know about rabbitea.rs subscribers? And surely the destination magazine must be involved somehow to run rules on like, banned users? otherwise that means any external user banned by fedia could continue to post forever with no way to stop them and it would still federate out everywhere

chris, 9 months ago

Yes, this doesn't make sense. How I thought it worked is that the originating server would push the new article to the home instance, and the other instances then pull from there (or the home server pushes; whatever, same net effect). If that isn't how it works, I don't see how it can work, as every server which posts to a magazine would need to know who subscribes to it. Certainly in the case of Mastodon, it doesn't have a concept of this, yet can post to communities/magazines and the comments federate out (maybe comments work differently though? There doesn't appear to be a problem with comments as far as I can tell)

dannekrose, 9 months ago

@e569668

why it isn't getting sent to rabbitea.rs

If feddit.uk doesn't know about rabbitea.rs, then it won't send it there. The originating instance is responsible for sending it out, but it can only send to instances it knows are subscribed. This can result in some instances not getting new content if it originates on an instance other than the one that is the "home" for a magazine.

And surely the destination magazine must be involved somehow to run rules on like, banned users?

That depends. It depends on if the "home" instance federates out blocks. I don't actually know if kbin federates out blocks (many Fediverse platforms don't actually because it's used as a vector for harassment and dogpiling and other very harmful behaviors), but the 2 cases are as follows:

1. If Kbin (or the "home" instance platform) federates out blocks, then all subscribing instances will receive the block information. Whether or not they honor it or not is not guaranteed, but for simplicity sake, let's assume they do.

In this scenario, instances that receive the block will behave as you might expect: they won't allow the blocked user to view the content in the magazine/community but will allow other users to view it. They also will not accept content into their local copy of the magazine from the blocked user.

2. If kbin (or the "home" instance platform) does not federate out blocks, then other instances cannot know not to display content from a blocked account, nor do they know not to accept content created by a blocked account. The "home" instance will block such content from being displayed and added to the magazine and thus users on the "home" instance will not see the content, but users on other instances could, in theory, still see the content.

Note: This is partially why the mod_log can be viewed. I'm not 100% sure of the details, but the home instance moderation decisions should be visible on other instances (or at least by visiting the magazine on the "home" instance itself) and moderators/admins should be able to take similar actions on their own local-copy of the magazine.

hitstun, 9 months ago (edited 9 months ago)

I'm having trouble with federation today. I've posted to my Kbin magazine 8 times in the past 24 hours, but two of them didn't federate to Lemmy. This article and this article aren't viewable on Lemmy.world. Sh.itjust.works is missing a lot but it actually has this article. Lemmy.dbzer0.com is only missing that one, though.. Bookwormstory.social actually got all the threads. This video made it onto Lemmy but the thumbnail I edited in is missing from all of them.

Kbin.social got everything I posted except for the video thumbnails. It might just be another Lemmy bug.