[horde] Can't add Outlook meeting request to Kronolith

Michael M Slusarz slusarz at horde.org
Thu Jan 10 00:38:30 UTC 2013

Quoting Michael J Rubinsky <mrubinsk at horde.org>:

> Quoting Michael M Slusarz <slusarz at horde.org>:
>> 1) The code is released under GPL.  However, the two most logical  
>> places to put something like this (Horde and/or a framework  
>> library) are released under LGPL.  So we'd have to do some annoying  
>> packaging tricks to work around this.
>> 2) It seems to me the proper solution would be to ignore the TZID  
>> information when the Icalendar data contains the timezone offsets  
>> (as in this case).  But I will defer to our ical experts to comment  
>> on this.
> This won't work for importing the iCal. Since the RFC does not  
> specify that the TZID need to conform to any standard, nor does it  
> state that the timezone rules specified need to actually match an  
> existing valid OLSEN/TZDB timezone (which is the cause of this  
> problem to begin with), we can't simply convert the provided  
> timezone rules/offsets into a known TZID - we would have to store  
> the entire VTIMEZONE component with the event data then EVERY time  
> we need the event's time we would need to use the VTIMEZONE to run  
> an algorithm to determine the current time we want. This would be a  
> nightmare. So, option (2) is not desirable.

Nevermind - I was reading the data/spec wrong.  There should be  
absolutely no reason we are parsing the timezone string in this case  
via PHP's DateTime since the timezone identification is explicitly  
defined elsewhere in the data (VTIMEZONE block).

So it looks like the Icalendar parser is not correctly parsing the  
VTIMEZONE block and using this defined timezone later in the VEVENT  
data (e.g. DTSTART/DTEND).  This indeed looks like a bug.


Michael Slusarz [slusarz at horde.org]

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