GMT offset in Google Calendars not being honored

[iancrew]

The iCal Feed dashlet doesn't appear to be honoring the timezone settings in an iCal feed from Google Calendar.

The events in the feed show as their GMT time, without taking into account the (currently GMT-7) offset to the PDT (Pacific Daylight Time) timezone. So, for example, an event entered for 5-6PM in Google shows up as being from midnight-1AM when viewed via the iCal Feed Dashlet.

See below for all the data. To me, this feels like a bug, but maybe I'm missing something settings-wise??

Thanks!

Ian Crew
UC Berkeley
http://directory.berkeley.edu/details.pl?uid=13442

Note the "Test 2" event in the following two screenshots:

vs:

The timezone is set correctly for the Alfresco server in the tomcat JAVA_OPTS via the "-Duser.timezone=PST" flag.

The timezone is set correctly for the calendar in Google:

As well as for the event itself:

An iPhone configured to read the same iCal feed shows the times correctly:

The start of the iCal Feed looks like:

BEGIN:VCALENDAR
PRODID:-//Google Inc//Google Calendar 70.9054//EN
VERSION:2.0
CALSCALE:GREGORIAN
METHOD:PUBLISH
X-WR-CALNAME:Hub Shared
X-WR-TIMEZONE:America/Los_Angeles
X-WR-CALDESC:
BEGIN:VTIMEZONE
TZID:America/Los_Angeles
X-LIC-LOCATION:America/Los_Angeles
BEGIN:DAYLIGHT
TZOFFSETFROM:-0800
TZOFFSETTO:-0700
TZNAME:PDT
DTSTART:19700308T020000
RRULE:FREQ=YEARLY;BYMONTH=3;BYDAY=2SU
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:-0700
TZOFFSETTO:-0800
TZNAME:PST
DTSTART:19701101T020000
RRULE:FREQ=YEARLY;BYMONTH=11;BYDAY=1SU
END:STANDARD
END:VTIMEZONE
BEGIN:VEVENT
DTSTART:20130426T230000Z
DTEND:20130427T000000Z
DTSTAMP:20130426T202743Z
UID:bn1j6ootlrr98mdmmtjprhppe8@google.com
CREATED:20130426T194225Z
DESCRIPTION:
LAST-MODIFIED:20130426T194225Z
LOCATION:
SEQUENCE:0
STATUS:CONFIRMED
SUMMARY:upcoming event (testing hub iCal dashlet)
TRANSP:OPAQUE
END:VEVENT

[wabson]

I can confirm this is a limitation of the current parsing, which does not take account of time zones. The parsing is done with the web script ical-feed-data.get.js, so either this would require extending, or replacing with a Java equivalent web script utilising a suitable library.

[iancrew]

Thanks Will. We (the University of California, Berkeley) are interested in this because it would be a simple way to integrate Google Calendar--which we use for all our scheduling on campus--into our Alfresco EE instance. I did a little poking around this morning, and I wonder if https://code.google.com/p/ijp/ might be useful as either a replacement for ical-feed-data.get.js, or as a guide to getting the timezone support working?

[wabson]

Thanks for the feedback. That's a really nicely-written little parser and also the best I could find out there, it's just a shame it doesn't support VTIMEZONE. Still, I'll create a separate branch and see if I can get that working, as the code looks to be pretty extendible.