Subject: [Ietf-calsify] DTSTART with assumed DTEND...

From: mgk at webfeet.co.uk (Martin Kiff)
Date: Mon Jan 29 10:30:57 2007

Hello list....

I've been following the recent discussion the archive and felt it was 
worth joining the list to contribute, if I cause waves let me know 
privately!

Re: DTSTART and DTEND, it seems we can:

* Specify an event with a given start and given end date and time, or 
start date and end date, where the booking is opaque. An event or an 
all-day event.
* Specify an event as above where the booking is transparent. Useful for 
anniveraries...

However how can we specify an event which we know is on a given day, but 
is _not_ an all day event, just that we don't have details of the times?

Giving just a
  DTSTART;VALUE=DATE:20070129
without a DTEND ought to be sufficient if it wasn't for the 'assumed' 
DTEND. Even then the assumed 'DTEND' would be no problem if UA's did not 
assume that a event with an assumed DTEND was a whole day event. Perhaps 
the spec can be clarified here...

Regards,
  Martin Kiff

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From: jeffrey at osafoundation.org (Jeffrey Harris)
Date: Mon Jan 29 11:09:35 2007

Hi Martin,

> the spec can be clarified here...

OSAF discovered that many people we surveyed wanted this distinction.
It's fairly subtle, but it appears there are lots of times all day and
transparent isn't quite right, it tends to suggest that the event won't
take any time.  So we added what we call an "anytime" status, which
leaves time fields visible but empty, ready to be filled out.

We serialize this distinction as an X-OSAF-ANYTIME-PARAM=TRUE parameter
in all day DTSTARTs.  We'd be delighted to do something more
standardized if there's broad interest in such a thing.

Sincerely,
Jeffrey

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From: Nigel.Swinson at rockliffe.com (Nigel Swinson)
Date: Mon Jan 29 11:18:21 2007

> standardized if there's broad interest in such a thing.

I'd like it too, but it does sound awkward to represent in a gui.  Until it has a time, you can only render it next to the day.  I'd opted for getting the user to supply a time and mark it as Tentative.

Nigel

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From: mikesamuel at gmail.com (Mike Samuel)
Date: Mon Jan 29 11:29:53 2007

Could this fit in with anything related to negotiating a time for a meeting?

It might be easier to do negotiation-based scheduling if it's explicit
that an event is tentative, but will probably fall within a range of
times.  That range of times could be successively winnowed until an
actual time is agred upon at which point it's DTSTART becomes a
date-time and it becomes opaque.

mike

On 29/01/07, Nigel Swinson <[email-masked]> wrote:
> _______________________________________________
> Ietf-calsify mailing list
> [email-masked]
> http://lists.osafoundation.org/mailman/listinfo/ietf-calsify
>

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From: mgk at webfeet.co.uk (Martin Kiff)
Date: Tue Jan 30 12:52:39 2007

>I'd like it too, but it does sound awkward to represent in a gui.  Until it has a time, you can only render it next to the day.  I'd opted for getting the user to supply a time and mark it as Tentat…
That might be ok when the user is noting the date (and time) in their 
own calendar, however there is also the case where the event is 
published on the web and the user wants to subscribe/copy it. If there 
was an event marked up with just:

I would expect to have _no_more_ information displayed by the UA; it 
should not give an end date, it should not show a flag saying 'all day 
event' and it should not force me to add a time. I'd also expect that if 
I saved this event elsewhere, _no_additional_information_ would be 
written (specifically it should not save 'an assumed' DTEND on my behalf)

However the above is describes the problems for the UA, I think where 
this affects this discussion is that the spec should not tempt people to 
believe that an event with simply a:

implies an all day event.

Regards, Martin