In looking over Yahoo's DataRSS spec (part of SearchMonkey), and after thinking about Bill DeHora's recent blog posts about JSON and Atom, I am reminded again how useful it might be to have a simple mechanism to add arbitrary metadata to an atom:feed, atom:entry, or atom:link. I realize this has been addressed in various ways before (esp. James Snell's link extensions proposal), but deconstructing/simplifying DataRSS just a bit, we could arrive at a metadata extension:
<x:meta property="[property name -- maybe a CURIE?]">value of the property</x:meta> This element would make an assertion about it's containing element, any of: feed, entry or link. The property value is always a simple string. The property attribute should , I suppose, be a CURIE, but I'd guess it could be a simple string as well. In DataRSS they have an optional "datatype" attribute, that holds a CURIE -- potentially useful, although I'd probably not use that. DataRSS uses a containing "adjunct" element, but I'd be happy to leave that out and assume that metadata assertions are being made by the creator of the atom feed or entry. The "item" element in DataRSS is (as far as I can tell) a surrogate for atom:link, so we don't need that. The other element DataRSS uses is "type," which this proposal doesn't address since there are other possible ways to do that in atom (or not do at all). It's apparent in the DataRSS docs that they realize the complexity comes not in the syntax, but in encouraging standard vocabularies and standard constructs for similar content types. As people standardize, more interop results. In the mean time, Atom can be all that much more useful for simple applications that just need a bit more metadata for a specific use case. I'd be curious to hear thoughts/opinions on this. --peter keane
