Nice to see a blogpost on the Mastodon blog about implementing a basic ActivityPub server

(Though technically webfinger isn't needed for activitypub, but it is for mastodon interop!)

@cwebber This blog post should be straightforward, but it's not ! 😠
What is really expected for an actor file to be accepted by Mastodon ??
When I search for
it returns 0 user. What's wrong with my file ? Thanks for any help !

@cerisara I'm not 100% sure but your actor is missing some of its collections[1]. Also the inbox uri does not return a proper inbox end-point.


@mariusor Thanks for the reply ! I tried to add inbox, outbox as requested by AP (but not by mastodon afaik), no luck with , although seems to see the actor (but cannot display its profile)

It'd be nice to have a detailed reqs documents somewhere for mastodon, because I'm not fan of reading all the source code ;-)

Thanks !

@cerisara anyway, cwebber is the wrong person to ask about mastodon. Check the author of the original article.

@mariusor @Gargron
Hi Gargron, I'm very sorry, but I'm having a hard time trying to get your "basic AP tuto" working. Could you please tell me what's wrong with my actor file here:

It'll probably only take 1 minute from your time, thanks anyway :)

@cerisara @mariusor does the webfinger file have the application//json content type?

@Gargron @mariusor Yes it does have
"type": "application/activity+json",
but even when searching directly for
mastodon returns 0 user

Thanks for your reply !


@Gargron @mariusor

No, you're right, actually the webfinger file does is not cast as json MIME: that may be the catch indeed ! 🙂

@Gargron @mariusor @rra

OK, it's working, it was indeed the MIME type of webfinger that needed to be application/json. Although I can't directly write the actor file URI as I thought I could, but I have to search for name@domain.

Thanks for your help !

I'm actually going to hire an engineer to develop a "scientific-resource oriented" AP server. Any hint greatly appreciated. Thanks !

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