On Thu, Jun 10, 2010 at 15:43, James Snell <[email protected]> wrote:
> <link rel="..." href="..." > notbefore="2010-06-10T12:00:00-08:00" > notafter="2010-06-10T01:00:00-08:00" /> 'notbefore' and 'notafter' are pretty ideal. > I would have no problem including these in the link extensions spec if > the supporting use cases are sufficiently generic. > > However, it might make more sense to define these as extension > elements to the link or entry... hard to say for sure without knowing > more about the specific use case and how the your entries are being > modeled. Okay, bit of background: building a feed which contains information about TV (or radio) programmes. there's some extra stuff in there relating them to actual broadcasts (RFC4078 crid:// URIs), but principally, it boils down to the usual atom:entry elements - title, summary, id, published timestamp and links to resources. What I'd like to include in this feed is a particular class of link which refers to a resource (or set of resources of different types) where the programme can be downloaded or streamed, generally for a limited period - usually starting about half an hour after the on-air broadcast concludes (at some point along the way I'll need to come up with some link relations to indicate 'on-demand' vs. 'linear broadcast', but that's a separate issue entirely). The user agents can be quite a lot smarter if they can determine from the feed whether a given programme is available for on-demand viewing/listening at a given point in time (not all will be, due to rights constraints); if so, how long the user has access to the resource, and if not, whether it will be for the future or if the window has already passed. I must confess I haven't thought deeply about wider applications of a notbefore/notafter - obviously limited-time availability for resources isn't particularly uncommon, but the intersection of those and the set of resources you want to appear in a feed might well be a different matter. I'm happy enough to roll my own extension for this, but if it's something generic enough to end up in link-extensions, I'd obviously rather see that happen. Cheers, M.
