Comments on: Django, iCal and vObject

By: Paul

Paul — Sat, 18 Aug 2007 21:00:30 +0000

For what it’s worth, here’s my simple example of using vObject with Django to produce vCard output.

By: The Bitter Pill : » Stupidly simple microformat syncing with Django’s generic views.

Fri, 10 Aug 2007 21:10:41 +0000

[...] Via Jeff Croft I saw Derek Willis’ solution for doing this with vobject. Looks like a great solution for icalendar links, but vobject struggles a bit with vcard, and I couldn’t get it to install on my shared server, so I kept looking. [...]

By: Geoff

Geoff — Tue, 07 Aug 2007 11:36:50 +0000

Excellent Derek - you’ve done it properly. Much nicer than the hack that I came up with for mactactic.

By: Doug Napoleone

Doug Napoleone — Thu, 02 Aug 2007 20:10:59 +0000

Jeffrey,

I switched to UTC at the very end due to problems caused by the MS patch. It was the only thing I could get to work everywhere. The change history on the version which worked one day and stopped the next is here:

https://pycon.coderanger.net/changeset?new=django%2Ftrunk%2Fpycon%2Fschedule%2Ftemplates%2Fschedule%2Fsched.ics%40234&old=django%2Ftrunk%2Fpycon%2Fschedule%2Ftemplates%2Fschedule%2Fsched.ics%40193

By: Empty

Empty — Wed, 01 Aug 2007 22:59:56 +0000

This is great stuff and pretty timely for me. Thanks.

By: Jeffrey Harris

Jeffrey Harris — Wed, 01 Aug 2007 17:45:30 +0000

I’m glad you’ve found vobject useful.

I’ve considered serializing a default METHOD to make Outlook happy, but rfc2445 makes METHOD optional, and CalDAV specifically forbids it, so I decided not to.

Doug, it looks like your template is using UTC times. If you want to use UTC times with vobject, that ought to work, your datetimes just need a UTC tzinfo class.

It’s probably better to use non-UTC timezones in iCalendar though, because if Congress changes daylight savings time again consumers of your data have at least some hope of figuring out what local time was originally intended.

vobject ought to handle floating datetimes (no timezone), datetimes in UTC, or datetimes in a non-UTC timezone. In this last case, iCalendar requires a VTIMEZONE, which vobject should create for you automatically.

If you had trouble getting timezones to serialize, I’d be interested to hear more on the vobject mailing list. Timezones are a pain.

Jeffrey

By: Derek

Derek — Wed, 01 Aug 2007 15:54:35 +0000

Doug,

As far as I know that issue hasn’t been fixed. Due to a quirk of our app, which lists events in their local times around the country rather than standardize on a single timezone, we basically ignored that part of it (which obviously would not work for everyone).

In general, vObject worked great with Macs and Google Calendar, and less so with Outlook and, especially, IE. So I’m pretty sure your experience still holds.

Derek

By: Doug Napoleone

Doug Napoleone — Wed, 01 Aug 2007 15:30:51 +0000

Question:
Do you know if the problems with the active feed and timezone’s have been fixed? I plan on checking myself but people might be interested in this.

I ran into a problem where it does not support active iCal feeds (think iCal+RSS), which is supported by google, and Mac. This became a required feature for the PyCon schedule app. I also ran into problems with the timezone. Congress changes the daylight savings time in the middle of our development, and at one point vObject data worked, the next it stopped working because of a MS patch for dealing with daylight savings. (DTTimeZone stopped working).

In the end I made my own ical django template which worked everywhere, not the most elegant solution.
https://svn.python.org/conference/django/trunk/pycon/schedule/templates/schedule/sched.ics
http://us.pycon.org/apps07/schedule/

By: Jeff Croft

Jeff Croft — Wed, 01 Aug 2007 14:51:45 +0000

Wonderful! This will definitely come in handy. Thanks!

By: Lorenzo Bolognini

Lorenzo Bolognini — Wed, 01 Aug 2007 11:48:27 +0000

Please add it to DjangoSnippets!