Add support for publishing mentions

[gRegorLove]

I'd like to be able to publish a note to start a conversation with someone (vs replying to a post in a thread). Also handy for tagging someone in a post in an existing thread.

I tried a couple ways a while back but they didn't show up as notifications for the person I mentioned:

https://gregorlove.com/2022/11/hello-from-my-website/ - linked the @-@
https://gregorlove.com/2022/11/hello-again-from-my-website/ - no @-@ link

[snarfed]

Yes! Great point, and BF already does the other direction, AP => wm (background in eg #270), so it should absolutely do this too.

[snarfed]

More motivation for this: the emerging standard way to do groups on the fediverse is evidently accounts that automatically repost you when you mention them, eg https://venera.social/profile/activitypubblueskybridge

[snarfed]

I've been trying to get this to work with a Friendica group, which works by reposting your posts that mention it, but no luck so far. Here are all the different AS2 Mention tags I've tried:

    "tag": [{
      "type": "Mention",
      "id": "https://venera.social/profile/activitypubblueskybridge",
      "name": "AP-AT-Bridge Group"
    }]

    "tag": [{
      "type": "Mention",
      "id": "https://venera.social/profile/activitypubblueskybridge",
      "url": "https://venera.social/profile/activitypubblueskybridge",
      "name": "@activitypubblueskybridge@venera.social"
    }]

    "tag": [{
      "type": "Mention",
      "id": "https://venera.social/profile/activitypubblueskybridge",
      "url": "https://venera.social/profile/activitypubblueskybridge",
      "href": "https://venera.social/profile/activitypubblueskybridge",
      "name": "@activitypubblueskybridge@venera.social"
    }]

...all with cc <a href=\"https://venera.social/profile/activitypubblueskybridge\">@activitypubblueskybridge@venera.social</a> in content and with this audience targeting:

  "to": [
    "https://www.w3.org/ns/activitystreams#Public",
    "https://venera.social/profile/activitypubblueskybridge"
  ]

🤷 🤷 🤷

[snarfed]

Mastodon docs for mentions: https://docs.joinmastodon.org/spec/activitypub/#Mention

I guess I could try some of the above ^ examples with cc instead of to.

[snarfed]

Tried again with cc, delivered this to https://indieweb.social/users/snarfed/inbox just now, it mentions and cc's https://indieweb.social/users/snarfed , but still no luck, that account didn't get a notification.

Next step is to hope @manton can help, he evidently has outgoing fediverse mentions working in micro.blog!

{
  "id": "https://fed.brid.gy/r/https://snarfed.org/2023-10-12_snarfed-foo-bar-mas-to#bridgy-fed-update-2023-10-12T23:44:49.320885+00:00",
  "actor": "https://fed.brid.gy/snarfed.org",
  "@context": "https://www.w3.org/ns/activitystreams",
  "type": "Update",
  "object": {
    "updated": "2023-10-12T23:44:49.320885+00:00",
    "published": "2023-10-12T16:35:43-07:00",
    "content": "hi again to <a href=\"https://indieweb.social/users/snarfed\">@snarfed@indieweb.social</a> <a class=\"u-in-reply-to\" href=\"https://mas.to/@snarfed/109668310494520038\"> </a>",
    "url": "https://fed.brid.gy/r/https://snarfed.org/2023-10-12_snarfed-foo-bar-mas-to",
    "id": "https://fed.brid.gy/r/https://snarfed.org/2023-10-12_snarfed-foo-bar-mas-to",
    "type": "Note",
    "attributedTo": "https://fed.brid.gy/snarfed.org",
    "inReplyTo": "https://mas.to/users/snarfed/statuses/109668310494520038",
    "tag": [
      {
        "type": "Mention",
        "href": "https://indieweb.social/users/snarfed",
        "name": "@snarfed@indieweb.social"
      },
      {
        "type": "Mention",
        "href": "https://mas.to/users/snarfed"
      }
    ],
    "cc": [
      "https://indieweb.social/users/snarfed",
      "https://mas.to/users/snarfed",
      "https://www.w3.org/ns/activitystreams#Public",
      "https://mas.to/users/snarfed/followers"
    ],
    "to": [
      "https://www.w3.org/ns/activitystreams#Public"
    ]
  },
  "to": [
    "https://www.w3.org/ns/activitystreams#Public"
  ],
  "cc": [
    "https://indieweb.social/users/snarfed",
    "https://mas.to/users/snarfed",
    "https://www.w3.org/ns/activitystreams#Public",
    "https://mas.to/users/snarfed/followers"
  ],
}

[manton]

I just tested this in Micro.blog and it's working. One thing I noticed in your example above, the type = "Update". Why not "Create"? Maybe Mastodon is confused by that.

Here's the JSON for sending an @-mention from the test account @mantondroid@micro.blog to @manton@indieweb.social:

{
  "@context": "https://www.w3.org/ns/activitystreams",
  "type": "Create",
  "id": "https://micro.blog/activitypub/ids/19f285fd5759d3170732",
  "actor": "https://micro.blog/activitypub/mantondroid",
  "object": {
    "id": "https://micro.blog/activitypub/posts/24869106",
    "type": "Note",
    "url": "https://mantondroid.micro.blog/2023/10/13/testing-a-mention.html",
    "published": "2023-10-13T13:49:49+00:00",
    "attributedTo": "https://micro.blog/activitypub/mantondroid",
    "tag": [
      {
        "type": "Mention",
        "href": "https://indieweb.social/users/manton",
        "name": "@manton@indieweb.social"
      }
    ],
    "content": "<p>Testing a mention to Mastodon. Hi <a href=\"https://indieweb.social/users/manton\">@manton@indieweb.social</a>. \ud83d\udc4b</p>",
    "attachment": [],
    "to": [
      "https://www.w3.org/ns/activitystreams#Public"
    ],
    "cc": [
      "https://micro.blog/activitypub/mantondroid/followers",
      "https://indieweb.social/users/manton"
    ]
  }
}

[manton]

This is also a new post, not a reply to anything specific, so I don't include inReplyTo. Pretty similar for replies to a post, though. I think only inReplyTo is different.

[manton]

Not sure if this matters, but why have the empty link username for the second Mastodon user that is mentioned?

[snarfed]

Woo, this is working! I honestly don't know what fixed it, but I won't argue. Docs are deploying now. Thank you @manton!

(Re your q's, I'd tried with Create too, and the empty second link was just a quirk of my site, unrelated to BF.)

[snarfed]

One silver lining of Mastodon's support here is that the AS2 Mention tag href isn't absolutely required to be the AP actor id, eg https://indieweb.social/users/snarfed. Mastodon also accepts the frontend URL that users see, eg https://indieweb.social/@snarfed.

[snarfed]

Reopening, this isn't working with Friendica groups, eg https://venera.social/profile/activitypubblueskybridge , which repost (Announce) your posts when you mention them. Sent this (trimmed here) to https://venera.social/inbox/activitypubblueskybridge a bit ago but it didn't work.

{
  "@context": "https://www.w3.org/ns/activitystreams",
  "type": "Create",
  "id": "https://fed.brid.gy/r/https://snarfed.org/2023-10-20_51173#bridgy-fed-create",
  "actor": "https://fed.brid.gy/snarfed.org",
  "published": "2023-10-20T19:27:57.093008+00:00",
  "object": {
    "type": "Note",
    "id": "https://fed.brid.gy/r/https://snarfed.org/2023-10-20_51173",
    "url": "https://fed.brid.gy/r/https://snarfed.org/2023-10-20_51173",
    "published": "2023-10-20T12:01:27-07:00",
    "content": "... cc <a href=\"https://venera.social/profile/activitypubblueskybridge\">@activitypubblueskybridge@venera.social</a>.</p>",
    "attributedTo": "https://fed.brid.gy/snarfed.org",
    "tag": [
      {
        "type": "Mention",
        "name": "@activitypubblueskybridge@venera.social",
        "href": "https://venera.social/profile/activitypubblueskybridge"
      }
    ],
    "cc": ["https://venera.social/profile/activitypubblueskybridge"],
    "to": ["https://www.w3.org/ns/activitystreams#Public"]
    "...",
  },
  "to": ["https://www.w3.org/ns/activitystreams#Public"]
}

[snarfed]

Here's the most recent post to that group, also trimmed a bit. I don't see an obvious difference yet: the Mention tags are identical, and the HTML mention links in content are a bit different, but their hrefs are also identical.

You evidently have to follow the group before you can post to it, which I did a while back, but maybe that follow didn't take?

{
  "id": "https://indieweb.social/users/tchambers/statuses/111048163021099999",
  "type": "Note",
  "summary": null,
  "published": "2023-09-11T19:28:15Z",
  "url": "https://indieweb.social/@tchambers/111048163021099999",
  "attributedTo": "https://indieweb.social/users/tchambers",
  "to": ["https://www.w3.org/ns/activitystreams#Public"],
  "cc": [
    "https://indieweb.social/users/tchambers/followers",
    "https://venera.social/profile/activitypubblueskybridge",
    "https://venera.social/followers/activitypubblueskybridge",
    "https://fed.brid.gy/snarfed.org"
  ],
  "conversation": "tag:indieweb.social,2023-09-11:objectId=76434671:objectType=Conversation",
  "content": "<p>important work from <span class=\"h-card\" translate=\"no\"><a href=\"https://fed.brid.gy/r/https://snarfed.org/\" class=\"u-url mention\">@<span>snarfed.org</span></a></span> as part of his AP to BlueSky/AT bridge... comparing Nostr, AP, and AT Protocols.... Chime in if anything here needs tweaking or fixing...  cc: <span class=\"h-card\" translate=\"no\"><a href=\"https://venera.social/profile/activitypubblueskybridge\" class=\"u-url mention\">@<span>activitypubblueskybridge</span></a></span></p>",
  "tag": [
    {
      "type": "Mention",
      "href": "https://fed.brid.gy/snarfed.org",
      "name": "@snarfed.org@snarfed.org"
    },
    {
      "type": "Mention",
      "href": "https://venera.social/profile/activitypubblueskybridge",
      "name": "@activitypubblueskybridge@venera.social"
    }
  ],
  "..."
}

[snarfed]

Haven't found anything in Friendica's docs or GitHub issues so far:

• https://wiki.friendi.ca/docs/groups-and-privacy https://wiki.friendi.ca/docs/forums
• https://github.com/friendica/friendica/issues?q=group+mention+tag
• https://github.com/friendica/friendica/issues?q=groups+mention+activitypub

[snarfed]

Hmm, that group actually did end up reposting my mention post after all, just a while later, at 21:36:12 UTC, or at least I'm guessing based on this HTML in the repost:

<span class="commented" style="display: none;">2023-10-22 02:16:53</span>
<span class="received" style="display: none;">2023-10-20 21:36:12</span>
<span class="created" style="display: none;">2023-10-20 19:01:27</span>

Not sure why the delay. But maybe this is working and I can close again after all.

[snarfed]

Following up here. Did some tests, turns out Mastodon's incoming mention handling is pretty relaxed.

• The Mention tag's href can be either the actor id (eg https://indieweb.social/users/snarfed ) or url (eg https://indieweb.social/@snarfed ).
• name isn't required at all.
• The mentioned actor doesn't need to be in cc.
• No HTML link in content is required.

So I'm relaxing BF's mention detection in #760.