I hadn’t really looked, but it turns out that Mastodon has incorporated microformats. It has h-feed and h-card, h-entry (a status), and h-cite (a boost). Plaint text properties (p-), e-content, and link properties (u-) are implemented. Indeed, they all surface when looking at a profile’s HTML source. This is what makes it possible to e.g. follow Mastodon feeds as h-feed, next to the existing RSS output and ActivityPub, and that e.g. Brid.gy can do its work to carry over any interaction on a Mastodon post to a blogpost here.

What I haven’t found was what I was looking for.
The ActivityPub protocol in its specs has several so-called Activity Types that drew my attention:

In short ActivityPub supports FourSquare and Dopplr like check-ins and travel plans. I’ve recently added that to my site in terms of microformats and was still wondering how to create a useful stream for it. I’ve been thinking about an OPML outline with schema.org attributes, or a dedicated RSS feed or h-feed. An ActivityPub stream might be of interest too, or even more. There’s a PHP implementation of ActivityPub that includes these Activity Types as well, meaning there’s potential to experiment for me.

I wonder, are there any actual implementations of these ActivityPub types currently?

21 reactions on “Mastodon Does Microformats, ActivityPub Does Check-Ins and Travel Plans

  1. @ton oh I’d love that. You’d still need to somehow de-duplicate places people ‘check in’ to. Just coordinates would likely not be enough. Tough to federate?

  2. I’ve started on a range of location-based services in (streams). Provided a proof of concept demo just a few weeks ago of posts sorted by distance from a given spot. Will add the relevant activities as this moves forward.

  3. @ton@m.tzyl.nl https://unfediverse.com/item/b5f6174b-76aa-44a0-8d43-302e6a479441 mike wrote the following post Sun, 02 Oct 2022 12:01:10 +1100 Here’s a proof of concept for geotagged posts. Note: Very few fediverse projects support geotagged posts and very few people have location tagging enabled even if their platform provides it. But here’s a screenshot of my stream sorted by distance from somewhere in Australia (the nearest post was tagged from Thailand 2 years ago on Pixelfed) , followed by the same stream sorted by distance from New York City (the nearest post is from Pennsylvania). Please note that this feature is still in its infancy clearly we need wider adoption to make it useful. I intentionally did not use any proprietary database functions so that you can use it with any SQL backend. When completed, we’re hoping to be able to provide a distance sort of geotagged content from either your current device location or an arbitrary location you provide.

  4. Sadly the timing here is a bit off. Mastodon added microformats2 years ago; they’re actually now in the process of removing them in the 4.0.0 release. May not be intentional, may just be a casualty of switching the whole app to be an SPA that requires JavaScript (aka JS;DR), which kills their IndieWeb compatibility, since it means other web sites and IndieWeb tools can’t fetch Mastodon posts over HTTP directly any more. Sad.


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