Nothing4You @ Nothing4You @programming.dev

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fwiw, the estimate number only states the max amount of activities behind. the real number can be lower, but not higher (unless sending is entirely broken on the instance being checked).

each activity being sent has a numeric id in the database. lemmy has an api that returns the id of the last activity that was either successfully sent to an instance or skipped when it didn't need to get sent (e.g. pm to a user on a different instance). there may also be holes in activity ids due to postgres implementation details for auto-incrementing sequence ids.

for determining the highest known activity id to compare it with the last activity id sent to a specific instance, you can just go through the successfully sent ids for all instances in the response and find the highest number across them all. then you can calculate the difference between the highest number and the number for the specific instance.

depending on the lemmy version and timing of the action, it can take up to 30 seconds for the activity queue to deal with new activities, so on a somewhat busy instance the delta is likely rarely going to be zero.

while this is generally what most people talk about when speaking of defederation, admins can also decide to remove communities locally without blocking the entire instance.

you might find some inspiration from https://breezewiki.com/ - either its codebase directly or using it as an intermediary while scraping

@fmstrat@lemmy.nowsci.com there's also rss feeds for communities

ugh, i didn't notice they're even hiding domains of remote communities for "simplicity" in most cases. that seems so much more dishonest tbh.

this isn't entirely true, they do have some comments on lemmy as well, here are some examples:

• https://programming.dev/u/vinaya@api.clubsall.com
• https://programming.dev/u/chester22@api.clubsall.com
• https://programming.dev/u/impresario@api.clubsall.com
• https://programming.dev/u/luckymann@api.clubsall.com
• https://sh.itjust.works/u/BlazeFromLemmy@api.clubsall.com

it seems to be primarily about their communities not federating though i guess?

and either nobody from there posted a post to a lemmy community yet or maybe it doesn't federate posts currently?

pretty much, yeah. lemmy has a persistent federation queue instead of fire and forget requests when activities get generated. this means activities can be retried if they fail. this allows for (theoretically) lossless federation even if an instance is down for maintenance or other reasons. if mbin has a similar system maybe they could expose that as well, but unless the system is fairly similar in the way it represents this data it will be challenging to integrate it in a view like this without having to create dedicated mbin dashboard.

lemmy has a public api that shows the federation queue state for all linked instances.

it provides the internal numeric id of the last activity that was successfully sent to an instance, as well as the timestamp of the activity that was sent, and also when it was sent. it also includes data like how many times sending was unsuccessful since the last successful send. each instance only knows about its own outbound federation, but you can just collect this information from both sides to get the full picture.

there is also https://phiresky.github.io/lemmy-federation-state/site to look at the details provided by a specific instance.

it's not just lemmy.world.

of the larger instances, the following have trouble sending activities to lemm.ee currently:

• lemmynsfw.com -> lemm.ee: 2.81d behind
• sh.itjust.works -> lemm.ee: 1.04d behind
• lemmy.world -> lemm.ee: 22.5h behind

i pinged @sunaurus@lemm.ee on matrix about 30h ago already about the issues with federation from lemmynsfw.com, as it was the first one i noticed, but I haven't heard back yet.

at least the image resizing topic has recently been fixed in lemmy, thumbnails sizes are limited (at the time of thumbnail creation) in the latest release. I'd have to look closer at the other stuff, the api part is unlikely to have changed and will affect all frontends, but js part should differ depending on the front end. some instances already use other frontends by default and there is also a replacement for lemmy-ui being worked on (lemmy-ui-leptos), but I don't know how they compare. either.

it should be taken into account though how much of this is cacheable as well, as it will then typically only affect the first load for the static files.

I can totally understand the issues in general though, I've been living with a 64kbps uplink for several years in the past.

requires sending ~25-fold less data per post

what are you referring to with this? AP traffic?

do you have some more information about this?

this doesn't just affect lemmy.ml.

it seems that lemmy.ml -> lemm.ee was somehow fixed yesterday, but there are several other instances that also have issues sending to lemm.ee:

• hexbear.net: was broken since 2024-10-23, fixed since 2024-10-25
• lemmy.blahaj.zone: broken since 2024-10-24
• lemmy.ml: was broken since 2024-11-01, seems fixed since 2024-11-16
• startrek.website: broken since 2024-11-15

peertube embeds are supposed to be fixed in lemmy 0.19.6, so when updating to that lemmy version they should start working again

does it work if you search again?

search for remote content sometimes doesn't show up the first time you try, searching again just after that can help.

if the channel still doesn't show up, does searching for an individual video work?

this is the important part.

when an account is deleted the associated private key used for signing activities is deleted as well. the activitypub protocol does not really define how software is supposed to deal with deleted and recreated actors (which includes users), so some software has been built with the assumption that any change of encryption keys for a user means it's an invalid signature and will prevent activities involving that user to federate to that software.

If the sole moderator of a community was banned from an instance, does that make the community unavailable to the instance they were banned from?

yes, if the ban was with content removal and they're the top mod.

If the community had multiple moderators and only one was banned, would that still be the issue?

the filter is whether the user being banned is the top mod.

this seems more of a federation issue than a defederation issue ;)

that is likely related to https://github.com/LemmyNet/lemmy/pull/5107, which limits the resolution of thumbnails.

the client you are using is probably only displaying the thumbnails to you, not the original images.

edit: this seems to include lemmy-ui as well

edit 2: raised a bug report for lemmy-ui

that is likely related to https://github.com/LemmyNet/lemmy/pull/5107, which limits the resolution of thumbnails.

the client you are using is probably only displaying the thumbnails to you, not the original images.

edit: this seems to include lemmy-ui as well

edit 2: raised a bug report for lemmy-ui

it may be related to the older lemmy version.

the latest lemmy version has changed how metadata is fetched for posts coming from federation and it will no longer be processed while receiving the federated activity, instead it will be processed in the background. sometimes, metadata for urls cannot be fetched within the time limit and then the post will not federate properly if it's not happening in the background.