Wednesday, September 24, 2003
RSS spec needs an expiration element
I'm new to RSS, having only given in to the nagging suspicion that I should look into it last week, so take this comment with a grain of salt, but the RSS spec(s, choose your favorite) need a way to indicate that the feed is no longer active. This would allow feeds to be auto-removed from a consuming application (be it a web aggregator or computer-installed RSS reader), potentially alerting the user that the feed is no longer available.
This is certainly useful for stopping feed readers from repeatedly visiting a server that no longer hosts a feed (come to think of it, is there a way to indicate that an RSS feed has moved?), but, more interestingly, this would allow ad hoc RSS subscription communities around transient topics. For example, one could subscribe to the comments for a particular entry on someone's blog. The server might have a rule that if no new comments are posted in 5 days to expire the feed for that set of comments. It could also be used to subscribe to a particular topic (and that topic only) on a bulletin board.
I can't count the number of times (in the last week) that I ran across an particularly interesting blog entry somewhere, and wanted to read the comments as they were posted (due to the nature of RSS, it's possible to view a comment as it's posted so that no one has had a chance to comment yet). This dovetails in with my desire to get bulletin board updates on a particular topic via email as well.
Now that I think of it, if you could subscribe to comments (which an expiration attribute helps make more feasible) AND you could indicate that the feed location has moved, you could get ad hoc groups of interest chatting about a thing spawned by a blog entry, and then move the whole thing to its own board or feed. Now THAT would be truly taking advantage of the power of the Internet.