Last REST Post of 2007

Here's the take-away from the past year's discussion about REST and geospatial. My own take, that is. There are differences of opinion among the participants of the Geo-Web-REST group.

REST is an architectural style, not an API. When you hear or read "... REST API ...", that's a smell, a signal that something might not be quite right inside.

REST is the architectural style of the World Wide Web. "Web API" is a more meaningful term, although not all Web APIs are RESTful. Some are GETSful.

The OGC service architecture is not RESTful. The style of the OGC architecture is non-RESTful CGI/RPC. Feature, map, and coverage resources are kept hidden behind service endpoints. We're still partying like it's 1999.

GML is compatible with REST, but XML Schema is still a wretched beast and there are no XLink-traversing GeoWeb browsers of note.

Look to Google Earth and KML for REST inspiration. It's about the links. Also look to Google's AtomPub-ish APIs for YouTube, Picasa, and OpenSocial. There's no transactional WFS involved there, and that's something to think about. Google chose AtomPub for wider interoperability.

REST is not a silver bullet. Distributed applications are hard.

These are the tenets of REST:

• Give every “thing” an ID

• Link things together

• Use standard methods

• Resources with multiple representations

• Communicate statelessly

Do read and recommend Stefan Tilkov's Brief Introduction to REST, from which the tenets above are taken. It's excellent.

Disregard the Emerging Technology: Geospatial Web Services and REST article in Directions. I don't care who linked you to it; they probably didn't read it very closely. This sounds mean, but that article will make you dumber about REST.