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My friend is working on adding ActivityPub support to his blog platform (BDServer) so people can follow/comment from Mastodon, Lemmy, etc.

Current status: Lemmy and Misskey can find and follow his account (@blenderdumbass@blenderdumbass.org), but Mastodon can't find it at all, even though he sees proper ActivityPub requests hitting his server.

The technical details are pretty gnarly - RSA signature verification, HTTP header recreation, multi-threading issues. He wrote up the full journey here: Please Help Me With Activity Pub

If anyone has ActivityPub experience or wants to take a look at the code (Python), we have a Matrix room for BDServer development. Any insights on why different platforms behave differently would be super helpful.

https://matrix.to/#/#bdserver:tchncs.de

Source code: ActivityPub.py

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[-] rglullis@communick.news 2 points 1 month ago

Maybe this kind of discussion will get more interested people on !activitypub@programming.dev .

[-] iso@lemy.lol 1 points 1 month ago

Happy cake day! ๐ŸŽ‚

[-] irelephant@lemmy.dbzer0.com 1 points 1 month ago* (last edited 1 month ago)

Did something change since this was posted?
I can look it up properly on mastodon.
You have to be signed in to fetch accounts on mastodon, is that the problem?

Are you using any framework to build the site? There's a few libraries for activitypub.
These links could be helpful: https://codeberg.org/fediverse/delightful-activitypub-development/

[-] blenderdumbass@lm.madiator.cloud 2 points 1 month ago

Seems like somebody mentioned the account on the fediverse that started a chain reaction of various instances requesting a bunch of stuff. Which made it to Mastodon.social too. It still doesn't work though.

The server is written in python and the idea is to make it deploy-able without needing to install anything extra. So I'm trying to implement my own activity pub.

[-] irelephant@lemmy.dbzer0.com 0 points 1 month ago

Running curl https://blenderdumbass.org/activitypub/account/blenderdumbass -H "Accept: application/activity+json" twice in a row outputs some bunkerweb anti-spam stuff.

[-] blenderdumbass@lm.madiator.cloud 1 points 1 month ago

try spoofing a user-agent or torifying it maybe

[-] flamingos@feddit.uk 0 points 1 month ago* (last edited 1 month ago)

I'm not the most knowledgeable about Mastodon's APub implementation, but having a look at the Actor of that profile, it might be because it's invalid JSON-LD. Now, Mastodon doesn't actually do proper JSON-LD checks, you can follow PieFed profiles from Mastodon and they don't produce proper JSON-LD, but they do include "https://w3id.org/security/v1" in their @context, and doing a code search of Mastodon's source code does show some checks for if that's included.

Lemmy's I am familiar with and irrc it doesn't even check if @context is present.

[-] irelephant@lemmy.dbzer0.com 1 points 1 month ago

I was trying something on lemmy a while ago and it required an @context.

this post was submitted on 08 Jun 2025
11 points (86.7% liked)

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