Daily Archives: 2003/09/15

RDF Forms

I’m pleased to announce the release of the first draft of RDF Forms. This is the first usable specification to emerge from some ideas that have been floating around in my head for a couple of years (in various guises). It looks brain-dead simple now, so I think (hope?!) that means that I probably got it right.

As an example of an RDF Form, here’s a query (aka GET) based one for the “Top downloads” service of Mark’s RESTful MS Web services front end;

<rf:Indexable xmlns:rf="http://www.markbaker.ca/2003/rdfforms/"
               xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
               rdf:about="http://www.diveintomark.org/msweb/TopDownloads">
  <rf:indexedBy rdf:resource="http://diveintomark.org/msweb/?WSDL#topType" rf:shortName="topType"/>
  <rf:indexedBy rdf:resource="http://diveintomark.org/msweb/?WSDL#topN" rf:shortName="topN"/>
  <rf:indexedBy rdf:resource="http://diveintomark.org/msweb/?WSDL#cultureID" rf:shortName="cultureID"/>
</rf:Indexable>

Thanks to Jan Algermissen and Aaron Swartz for their help (though Aaron didn’t know he was helping on this when he answered a question for me 8-).

feed://?

Greg’s asking for comments on the using a feed URI scheme to identify a subscription action for the feed, e.g. “feed://http://example.org/rss.xml”.

I think we can do better. Here’s two big reasons why I don’t like this proposal;

  • “Clicking” on a URI should always be safe, and provide information about the identified resource, not take an action upon it. This enables humans and automata to be able to trust that they’re not entering into an obligation by dereferencing a URI (any URI, not just http URIs).
  • The resource really is “http://example.org/rss.xml”, and putting “feed://” on the front obfuscates that from parties who don’t know what “feed://” means.

So what’s the better proposal? For one, get folks to start using an RSS-specific media type so that the client knows it’s RSS. Then you just need to register your aggregator as the application that handles that media type. Within the aggregator, I would expect to see that feed after clicking on the URI, but with a BIG “SUBSCRIBE” button in plain site when it realizes that I’m not already subscribed to that feed. As a bonus, there’s no need for a different “subscription URI”.