Thanks @pfefferle@mastodon.social! All I did was implement the protocol as many others have done. Half the credit would go to you as well for the other end of the integration!
It is really cool to be able to follow a blog from a forum. Are comments from the fediverse integrated?
@julian The plugin federates posts and comments.
But for now, a WordPress User can only be followed, I have no idea how to implement the following part nicely (yet).
@julian btw. I would love to understand/support how NodeBB handles categories and groups!
@pfefferle@mastodon.social I think there's a bit of a push to provide a full fediverse client (that includes two-way interaction between users). That's what the NodeBB integration is trying to do — to be that all-in-one fediverse client.
But the reality is there's no reason you have to do that. Simply federating content out and maybe ingesting responses back as comments would be a feature complete integration as far as I'm concerned! Anything else is gravy.
@pfefferle@mastodon.social categories in NodeBB are exposed via ActivityPub just like users, so they can be followed by remote users (just like how local users can "watch" a category, I suppose).
We follow FEP-1b12 at the moment, which means all posts are Announced by the category actor to any followers.
@julian I do that for the blog-wide user. It is from the type group and boosts all posts from every author. But it seems to be not compatible with NodeBB for now?!?
@pfefferle@mastodon.social what was the issue, are you not able to follow the blog-wide user?
May I have the handle so I can take a look?
@julian yes, couldn’t follow! It is @notiz.blog
@julian and I have to debug comments... they seem to also be broken :(
Can you maybe give me a level where I can post more often?
Hey @pfefferle@mastodon.social, I looked into it, and NodeBB can successfully resolve your instance actor via webfinger, but cannot make an S2S GET call to https://notiz.blog/@notiz.blog
I receive the following error:
{
"error":"This method requires an authenticated user"
}
@pfefferle@mastodon.social said:
Can you maybe give me a level where I can post more often?
Done! Your local account just needed a couple upvotes I think, so I did that now.
@julian ok, comments seem to come through today... maybe a glitch or an issue with missing upvotes?
@julian The HTML version (HTTP Request without Accept header) does redirect to the main page, but if you add the Accept header to get the JSON it will work even without signature. (I have not yet enabled AUTHORIZED_FETCH).
I ran some tests and it seems to work up to the Follow `Accept` response where I receive a 500 from the NodeBB inbox.
@pfefferle@mastodon.social any chance you could let me know the json you're sending during the Accept phase?
@julian sure, I will send you a DM!
@pfefferle@mastodon.social ah sorry, NodeBB cannot accept DMs at this time. Any chance you can message @devnull@crag.social ?
@pfefferle@mastodon.social Should be fixed now in https://github.com/NodeBB/NodeBB/commit/700016649d25ee5bc6c3fa17e03003677d7f5b5d (not yet deployed here).
The issue was that apparently for the blog actor WP sent actor URI and not username@host - which AFAIK is perfectly valid, NodeBB just assumed the latter was always the case 
@oplik0 ah, maybe its that we use domain@domain as WebFinger ID?
@pfefferle@mastodon.social the NodeBB community is updated to include @oplik0's commit, so you can try again 