Over the last year, we’ve made some changes to how Calagator works with tags. Events have them, and venues have them, but they aren’t very useful if you can’t use them to link to other things. So we’ve been working on that.

Popular tags for events are displayed in the left sidebar of the main page:

Calagator: Portland's Tech Calendar

If you go to an event page that has tags, you will see something like this:

Calagator Code Sprint » Calagator: Portland's Tech Calendar

Click on any tag’s link and it will take you to a search page with all events (or venues, if you’re on a venue page) that share that tag name.

Calagator also recognizes a special kind of tag, known as a machine tag. Machine tags are a way of providing short pieces of structured data. In our case, we’re using them to link to the Plancast or Upcoming pages for an event, letting you see who else you know might be attending.

Lunch 2.0 at the Portland Development Commission » Calagator: Portland's Tech Calendar

Not only that, but thanks to a contribution by Max Ogden, Plancast tags do one more thing:

Portland Ruby Brigade monthly meeting » Calagator: Portland's Tech Calendar

All attendees for that plan are displayed on the Calagator event page. Pretty neat.

The basic format for a machine tag is ‘source_name:reference_type=reference_id’. For Plancast, that looks like ‘plancast:plan=plan_id’ (you can get the plan id from the url on their site).

Our tag model includes a list of sources and types of links currently supported. In addition to the two sources mentioned above, useful for events, you can tag venues with the relevant Foursquare, Gowalla, and Shizzow links. We also have support for ePDX tags, which can be used to link to things like a sponsoring company, the person who’s organizing an event, or the user group the event is part of.