Make an API of your website

Lately I’ve been thinking a lot about data portability in terms of API’s, microformats and standards like SIOC, FOAF, OWL and APML. What fascinates me is that data portability enables people to share and move their data around the web seamlessly. I wrote about some microformats and standards for the semantic web a few days ago, but what about the API’s?

Nowadays, an API most often comes in the form of a REST service that returns JSON or XML, so that both JavaScript and server-side technologies can use them. It makes sense and it promote data portability. Then think about a website. Some parts of it are tagged up with various microformats like XFN, hCard and hCalendar, but what about the rest of the content?

My idea is to render any webpage in either XML or JSON if a certain parameter is added to the URL. It could look like this:

www.example.com/about.aspx?format=xml

Then the about.aspx page would render the output as XML for machines to read and thereby have some sort of read-only API. The standard could be RSS or ATOM or both. Now any machine can read the content of your website easily. Think about how easy it must be for search engines to index an RSS representation of a webpage instead of going through all the excess mark-up and style information.

If any webpage could be served as RSS, ATOM and JSON then the content of that page could be consumed in a multitude of ways. The best thing is that it is relatively easy to implement. Because it is so easy I can’t stop wondering if there is a reason no one has done it before.

The question is who would use this and does it make any sense to begin with?