From: e2 [mailto:e2@sympatico.ca] Sent: Thursday, February 23, 2006 11:22 AM
I've looked and cannot find a web service (e.g. SOAP) for providing local time conversion using Arthur Olsen's up-to-date timezone/daylight savings data.
I don't know of anything specific to SOAP, no. For at least five years the XML guys have attempted to redo the iCal format in XML, which sort of sounds like what you're interested in. See <ftp://ftp.rfc-editor.org/internet-drafts/draft-royer-calsch-xcal-03.txt> for their latest attempt. So far, those attempts have not succeeded: the calendaring guys continue to prefer straight iCal. We tz maintainers have stuck with Arthur David Olson's circa-1986 text format, under the "why fix what ain't broken?" theory. If all the iCal/SOAP/XML/whatever guys got their act together and defined a common format that in practice worked better than the traditional one, I'd be all ears. So far, though, that hasn't happened. I have asked for better-than-Olson-format features (e.g., enough primitives to support standard time in the Netherlands from 1835 to 1937), but without success; this is not a good sign. You might want to be aware of the Calendar Access Protocal (CAP) described in Internet RFC 4323 <http://www.ietf.org/rfc/rfc4324.txt> (December 2005). It describes a protocol whereby a client can get up-to-date data in VTIMEZONE format. This protocol is still experimental, but its authors expect it to evolve into something that's actually supported by vendors. My guess is that they're aiming to drop support for time zone data via CAP, substituting FTP to acquire time zone data in iCal format. See <ftp://ftp.rfc-editor.org/internet-drafts/draft-royer-timezone-registry-03.txt>. I don't know how well that's progressing, though.