[uf-discuss] UTC Datetime formats & Google calendar

Rebecca Cox lists at reb.net.nz
Thu Jul 19 19:06:46 PDT 2007

Hi all,

Apologies if this has previously been asked.

I've been trying out hcalendar and been having some issues with the
datetime format.

I'm in New Zealand (UTC +12), am using Operator to add my hcalendar
events to Google calendar.

If I use the hcalendar creator
http://microformats.org/code/hcalendar/creator - this puts in the time
format with offset from UTC appended, like so:

<abbr class="dtstart" title="20070720T0900+1200">July 20, 2007  9am</abbr>

All good, but Google Calendar doesn't like it, gives an error when you
try to add an event to your calendar via Operator.

If I markup times with no UTC offset, ie in my local time:

<abbr class="dtstart" title="20070720T0900">July 20, 2007  9am</abbr>

Google Calendar will grab the event OK, all good under the assumption
that the time is given for timezone of the event's location. Not so
useful if the event is online or otherwise more than one timezone.

If I markup times in UTC time, but display the NZ time eg:

<abbr class="dtstart" title="20070719T2100Z">July 20, 2007  9am NZT</abbr>

Google Calendar also likes this one, and will convert the UTC time to
my local time. Useful, but perhaps doesn't give the user enough
control over how the timezones are handled?

Perhaps this is a non issue. Say someone in the UK added my event, to
be held in New Zealand, to their Google Calendar. It would get
displayed to them in UK time. Then say they travelled for the event,
and switched their calendar timezone to NZ time while they were here,
so keeping to the correct time for the event. I guess the issue is
making it clear to the user that this is what will happen?

My thoughts are, for an event located in New Zealand perhaps do something like:

<abbr class="dtstart" title="20070719T2100Z">July 20, 2007  9am NZT,
(July 19, 2007  9pm UTC)</abbr>

What are people's thoughts on giving times, would you normally just
give the local time and not worry about timezones? What about for
online events where the timezone does matter?

Also wondering if any of the other hcalendar - using applications or
services have problems when times are given with the offset?


More information about the microformats-discuss mailing list