problems with developing with libical

[Patrick Ohly]

On Wed, 2014-10-15 at 21:59 +1300, Michael Cree wrote:
> On Thu, Oct 09, 2014 at 11:27:27AM -0400, Ken Murchison wrote:
> > On 10/03/2014 10:12 PM, Michael Cree wrote:
> > >Now I am trying to write VCALENDARs with both VTIMEZONEs and VEVENTS
> > >and using the TZID on DTSTARTs, etc.  I am currently using the builtin
> > >"Pacific/Auckland" timezone and if I create a VTIMEZONE for a calendar
> > >by:
> > >
> > >vtimezone = icalcomponent_new_clone(icaltimezone_get_component(tz));
> > >
> > >  Why doesn't it use a RRULE?  That's what the
> > >original builtin timezone in the zoneinfo directory has.  So I am
> > >wondering what is the best why to get a compact VTIMEZONE written
> > >out to an icalendar event file, and with the tzname of the VTIMEZONE
> > >matching the tzid value of the DTSTART parameter (as I presume they
> > >should)?
> > 
> > libical uses the vzic tool for creating VTIMEZONE components from the IANA
> > tzdata.  As you noted, its over use of RDATEs is annoying. I have local
> > changes to vzic that I'm using to create VTIMEZONE components for my
> > implementation of a Time Zone Distribution Service
> > <http://tools.ietf.org/html/draft-ietf-tzdist-service-01> and Time Zones by
> > Reference
> > <http://tools.ietf.org/html/draft-ietf-tzdist-caldav-timezone-ref-00>.  The
> > major changes are better use of RRULEs and sub-components sorted by DTSTART.
> > I will look at integrating my changes in libical.
> 
> That would be nice.

See also http://sourceforge.net/p/freeassociation/bugs/95/

+1 for enhancing VTIMEZONE definitions in libical again. A SyncEvolution
user recently complained about excessive network traffic when syncing a
calendar hosted on Radicale:
https://bugs.freedesktop.org/show_bug.cgi?id=86335

He pointed out that it takes 26MB to transfer the items which fit into a
300KB .ics file.

I haven't checked whether Radicale really uses libical, but from a log
that I was sent it looks like including historic VTIMEZONEs in each
VEVENT is to blame for the inflation.

Bye, Patrick