TL;DR: Any of you who are more familiar with Fediverse platforms that aren't Lemmy/Piefed, can you let me know what the AP_IDs look like for users, posts, comments, and, if applicable, communities?

So, I've rewritten the search / search boxes in Tesseract to skip the search and directly resolve activity pub URLs for users, posts, comments, and communities. I'm loving this as it makes things so much faster and easier.

To make that work, and reduce false positives/negatives, I have to do some pre-flight checks on the URL that's submitted to the search.

Currently, it checks if the domain is to a known federated instance and looks for specific paths in the URL. If it detects the URL is an AP_ID URL, it will only resolve the object and redirect you to it (skipping the lengthy search step). For false negatives, it will pass it to the regular search but still try a federated lookup along with the search.

For Lemmy and Piefed, those are:

/u/ for users
/c/ for communities
/post/ for posts
/comment/ for comments.

For Mbin, I think it's the same except it uses /m/ for communities (they call them "magazines" I believe).

I think mastoon uses /user or maybe /username/ in the AP identifiers?

Any of you who are more familiar with Fediverse platforms that aren't Lemmy/Piefed, can you let me know what the AP_IDs look like for users, posts, comments, and, if applicable, communities?

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[–] Jayjader@jlai.lu 3 points 3 weeks ago* (last edited 3 weeks ago) (1 children)

From my own experience querying public mastodon timelines via API (edit: removed incorrect /api/v1s in the AP_IDs):

Mastodon user accounts have an ActivityPub URI of https://<instance.domain.tld>/users/<username>
Mastodon posts have an ActivityPub URI of https://<instance.domain.tld>/users/<post_author_username>/statuses/<post_id> (they also have a url property of https://<instance.domain.tld>/@<post_author_username>/<post_id> but that tends to serve the html view of the post)

To see for yourself, pick an instance that allows viewing their public timeline without logging in (mastodon.social is perfect for this) and follow the "Playing with public data" section of the docs. That page ellides most of the info you're looking for in the example payloads they give (as the JSON payloads themself are quite large and nested), but I can assure you that AP_IDs for user accounts and posts can be found pretty quickly from a single timeline query.

I don't think Mastodon has any notion of community, nor does it distinguish between posts and comments (when following a lemmy community, both posts and comments show up in my masto feed as "top-level" statuses (ie posts)).

[–] admiralpatrick@lemmy.world 2 points 3 weeks ago

Cool, thanks. I was close with /user guessing from memory.

I think the /users/.../post_id will be sufficient. It just needs to know that the given URL is an AP_ID before passing it off to the API call to resolveObject. Since it already knows instance.domain.tld is a federated instance, it just needs to see if the path is an AP_ID or the HTML (or something else). Thus, I don't have to parse the whole thing, just check that enough of it matches.

Thanks!