Replies to federated comments

[snan]

On this federated thread I replied to the comment which shows up in the Friendica original but not on the lemmy.ml view.

When I reply to comments that are directly on lemmy, it works fine.

[dessalines]

Could you show which one is missing on the lemmy.ml view?

The comment that starts with: "Other issue I face" seems to be in both places.

[snan]

My missing posts start "maybe that would be good" and "and for some reason".

[Nutomic]

I managed to fetch your comments to lemmy.ml by pasting their urls into the search bar. So this doesnt look like a bug, but some kind of network issue.

[snan]

My thinking is that activities were sent to the actor where the thread "lives" i.e. on Nerdica

[Nutomic]

Ah, its possible that Friendica delivers activities differently. In case of Lemmy, activities get sent to the community (as cc), and the community sends it as Announce to its followers.

cc @annando

[annando]

Friendica will always post any activity to the thread creator. Depending on some other constellations, the activity will also be delivered to the thread participants and possibly the followers of the actor.

[Nutomic]

I see, the community is not listed in to/cc fields of https://idiomdrottning.org/objects/c337b8db-061a-4c96-b6d4-9fd2e1a4ba0d, so it obviously couldnt receive the comment. I think your logic should be like this: when replying to a post/comment which has a Group in to/cc, you also need to copy that group id into the Note to/cc, and deliver the Create activity to the group inbox. And it needs to be the group id, not the followers collection.

[annando]

The system at https://idiomdrottning.org doesn't appear to be a Friendica system. It appears to me like possibly Pleroma.

But concerning the issue: Have you checked that the problem always happens when a post had been started via someone (Lemmy or Friendica user) and someone from Friendica replies to someone from Friendica?

[Nutomic]

Sorry you are right, i was just assuming Friendica because that was mentioned in the issue. Looks like a problem with Pleroma then.

[snan]

Correct, it's when Pleroma replies to a Friendica on Lemmy-community thread..

[Nutomic]

@clearlyclaire @lanodan This is a problem in both Pleroma and Mastodon. In short, Lemmy indicates that a post or comment was made inside a group by putting that group id in to or cc. But when Mastodon/Pleroma reply to a post/comment inside a group, they only include the id of the post creator. This happens to work if the user and group are located on the same instance, as was very common with lemmy.ml. But if the user is from a different instance, these comments will not reach the group, and cant be announced to its followers.

I made an example here, a post was made from ds9.lemmy.ml to the community main@voyager.lemmy.ml.

https://ds9.lemmy.ml/post/22033

https://voyager.lemmy.ml/post/1743

As you can see, both comments only reach the user's instance (ds9.lemmy.ml), but not the group's instance. You can see the activitypub json for each comment from the link behind the colored "fedilink" icon.

What you should do is this: when replying to an object with a group in its to/cc field, copy that to your own to/cc, and deliver the activity to its inbox.

[annando]

@Nutomic Friendica should behave correctly. Have you checked this or should I perform some checks on my side to be sure?

[Nutomic]

@annando I dont have a Friendica account, so it would be good if you could check.

[annando]

In a first test it seemed to work. But I realized some issues since I imported the starting post and also the group actor was unknown. I have to repeat such a test with some test post in a group that I already have subscribed.

[snan]

I've been looking into migrating from Pleroma to GoToSocial and today I stumbled across this, which seems to be about the same issue as this Lemmy thread: https://docs.gotosocial.org/en/latest/federation/behaviors/conversation_threads/

[macgirvin]

What you should do is this: when replying to an object with a group in its to/cc field, copy that to your own to/cc, and deliver the activity to its inbox.

I didn't see this in the spec. Did I miss it someplace?

[annando]

@macgirvin the group handling isn't specified in the specs, so we will have to create some best practices.

[macgirvin]

Good luck with that. We've got close to a dozen incompatible group implementations now, some of which aren't even documented - and some of them conflict with others. Like this one.

[annando]

At least Lemmy, gup.pe and Friendica are interoperable and also users from Mastodon, Pleroma or Misskey can participate in group discussions.

[snan]

I see Lemmy as sort of a super Guppe (since it has a web thread view and moderation). ♥ Thank you for making it

[Nutomic]

@macgirvin I really havent come across any incompatible, activitypub-based group yet. Can you name some of these projects, and ideally some documentation about their implementation?

[Nutomic]

FEP-1b12 documents how Lemmy groups work.

[verymilan]

Hmm but https://discuss.tchncs.de/post/24294 seems to lack some Lemmy replies ... subbed to some source server communities, hoping it will help with the situation...

edit: the number of missing posts decreased, maybe the delay is higher than i thought

edit2: about 40min later, only one is currently missing ... well thats just slow i guess

[snan]

Here is a comment that did not show up:

https://idiomdrottning.org/notice/AWcqfGUIh0jiQVOJPs

Even though some of my other comments have shown up there, after some delay:

https://feddit.de/u/Sandra@idiomdrottning.org