Expressing date range in coverage

["Bill Kearney" <wkearney99@hotmail.com>]

Hi all,

I think I've found something that might be useful when added to an RSS feed.

The Dublin Core supports an element called "coverage".  It can be used to
express a range of time.  At it's most basic this could be used to indicate what
range of time the items within the feed instance cover.

This could be formed using DCSV formatting:
<dc:coverage>start=2002-09-20T20:01:19Z; end=2002-11-01T23:39:19Z;</dc:coverage>

Or as:
<dc:coverage start="2002-09-20T20:01:19Z" end="2002-11-01T23:39:19Z" />

Or even:
<dc:coverage>
    <start>2002-09-20T20:01:19Z</start>
    <end>2002-11-01T23:39:19Z</end>
</dc:coverage>

DCMI Period using coverage allows for a lot more than just timestamp ranges.
There's a way to express schemes as well.  I'm not terribly interested in the
alternative scheme possibilities as they're not terribly likely to be useful in
a newsfeed context.  I suppose the Caesar weblog might use another one. But for
the staggering majority just using W3CDTF (the default) scheme is quite
adequate.

The expectation here is this would be contained within the channel context.  I
suppose it could be contained within the items context (the rdf:Seq) but that's
probably more trouble than it's worth.  Semantically this would indicate that
this particular channel instance contains elements spanning from the start to
the end timestamps.  This could be quite useful to something looking to 'keep
current' with a feed.  It'd also be a possible step toward doing fractional
retreival of feeds.  As in, you could ask a mythical dynamic feed server to hand
you a feed "covering" a given start/end range.

I'm sure there's even several other ways to express it.  I'm wondering what most
developers would consider to be the 'least painful' way to format it?  What's
the consensus on formatting it for good RDF-ness?

-Bill Kearney


http://dublincore.org/documents/dcmi-period/#dcsv