thr3ads.net - icalendar devel - [iCalendar-devel] Handling start and duration but no end for Events [Mar 2007]

If this information is useful, please help other people find it:
Share via:

Eric Pugh

2007-Mar-30 14:57 UTC

[iCalendar-devel] Handling start and duration but no end for Events

Hi all,

I''ve got an event that looks like:

BEGIN:VEVENT
DTSTART;TZID=US/Eastern:20070402T140000
SUMMARY:Call Robert
UID:A11B2175-8082-4839-B253-74D1A6CACBA9
SEQUENCE:4
DTSTAMP:20070329T150439Z
DESCRIPTION:Call to find out about bringing in Window guys......   \n\n4
34-962-7950
DURATION:PT1H
BEGIN:VALARM
ACTION:AUDIO
TRIGGER:-PT15M
X-WR-ALARMUID:76466515-A5C5-41C1-AECF-BF8C8BF972E0
X-ICF-AUTOALARM:TRUE
ATTACH;VALUE=URI:Basso
END:VALARM
END:VEVENT

It has a start time, but no end time.  However, it does have a  
duration of PT1H.   My app is failing cause I have no end time.   
Should the iCalendar parser handle the fact that the end time isn''t  
definined, and supply it based on the start time + duration?  Or is  
this the responsibility of the user of the parser???

I''m asking more from an understanding point of view?  Seeing if I  
should patch icalendar parser or deal with it in my code.

Eric


-------------------------------------------------------
Principal
OpenSource Connections
Site: http://www.opensourceconnections.com
Blog: http://blog.opensourceconnections.com
Cell: 1-434-466-1467

Rob Kaufman

2007-Apr-02 17:39 UTC

head link

[iCalendar-devel] Handling start and duration but no end for Events

According to the icalendar spec, you must specify EITHER duration or
end, so it would make a lot of since for setting duration to
implicitly set end in the parser and vis-versa.  You are correct that
the parser does not currently handle the case where there is no end.

Rob Kaufman

On 3/30/07, Eric Pugh <epugh at opensourceconnections.com>
wrote:> Hi all,
>
> I''ve got an event that looks like:
>
> BEGIN:VEVENT
> DTSTART;TZID=US/Eastern:20070402T140000
> SUMMARY:Call Robert
> UID:A11B2175-8082-4839-B253-74D1A6CACBA9
> SEQUENCE:4
> DTSTAMP:20070329T150439Z
> DESCRIPTION:Call to find out about bringing in Window guys......   \n\n4
> 34-962-7950
> DURATION:PT1H
> BEGIN:VALARM
> ACTION:AUDIO
> TRIGGER:-PT15M
> X-WR-ALARMUID:76466515-A5C5-41C1-AECF-BF8C8BF972E0
> X-ICF-AUTOALARM:TRUE
> ATTACH;VALUE=URI:Basso
> END:VALARM
> END:VEVENT
>
> It has a start time, but no end time.  However, it does have a
> duration of PT1H.   My app is failing cause I have no end time.
> Should the iCalendar parser handle the fact that the end time
isn''t
> definined, and supply it based on the start time + duration?  Or is
> this the responsibility of the user of the parser???
>
> I''m asking more from an understanding point of view?  Seeing if I
> should patch icalendar parser or deal with it in my code.
>
> Eric
>
>
> -------------------------------------------------------
> Principal
> OpenSource Connections
> Site: http://www.opensourceconnections.com
> Blog: http://blog.opensourceconnections.com
> Cell: 1-434-466-1467
>
>
>
>
> _______________________________________________
> icalendar-devel mailing list
> icalendar-devel at rubyforge.org
> http://rubyforge.org/mailman/listinfo/icalendar-devel
>

Eric Pugh

2007-Apr-02 18:53 UTC

head link

[iCalendar-devel] Handling start and duration but no end for Events

I''ve been going over this in my mind...  If you assume that the  
iCalendar tool is purely a "parser" then maybe it works the way you  
would expect, returning nil for the end, instead of figuring it out.   
Because that is what the "parsed" data says.  However, if you think  
there should be some handholding from the parser, or that you have  
two layers, the low level data and higher level user objects, then  
the higher level user objects should handle this then!

I think I may just add a layer to my app that adds those sorts of  
higher level "convenience" methods.  argh...

Eric Pugh




On Apr 2, 2007, at 1:39 PM, Rob Kaufman wrote:
> According to the icalendar spec, you must specify EITHER duration or
> end, so it would make a lot of since for setting duration to
> implicitly set end in the parser and vis-versa.  You are correct that
> the parser does not currently handle the case where there is no end.
>
> Rob Kaufman
>
> On 3/30/07, Eric Pugh <epugh at opensourceconnections.com> wrote:
>> Hi all,
>>
>> I''ve got an event that looks like:
>>
>> BEGIN:VEVENT
>> DTSTART;TZID=US/Eastern:20070402T140000
>> SUMMARY:Call Robert
>> UID:A11B2175-8082-4839-B253-74D1A6CACBA9
>> SEQUENCE:4
>> DTSTAMP:20070329T150439Z
>> DESCRIPTION:Call to find out about bringing in Window guys......    
>> \n\n4
>> 34-962-7950
>> DURATION:PT1H
>> BEGIN:VALARM
>> ACTION:AUDIO
>> TRIGGER:-PT15M
>> X-WR-ALARMUID:76466515-A5C5-41C1-AECF-BF8C8BF972E0
>> X-ICF-AUTOALARM:TRUE
>> ATTACH;VALUE=URI:Basso
>> END:VALARM
>> END:VEVENT
>>
>> It has a start time, but no end time.  However, it does have a
>> duration of PT1H.   My app is failing cause I have no end time.
>> Should the iCalendar parser handle the fact that the end time
isn''t
>> definined, and supply it based on the start time + duration?  Or is
>> this the responsibility of the user of the parser???
>>
>> I''m asking more from an understanding point of view?  Seeing
if I
>> should patch icalendar parser or deal with it in my code.
>>
>> Eric
>>
>>
>> -------------------------------------------------------
>> Principal
>> OpenSource Connections
>> Site: http://www.opensourceconnections.com
>> Blog: http://blog.opensourceconnections.com
>> Cell: 1-434-466-1467
>>
>>
>>
>>
>> _______________________________________________
>> icalendar-devel mailing list
>> icalendar-devel at rubyforge.org
>> http://rubyforge.org/mailman/listinfo/icalendar-devel
>>
> _______________________________________________
> icalendar-devel mailing list
> icalendar-devel at rubyforge.org
> http://rubyforge.org/mailman/listinfo/icalendar-devel
-------------------------------------------------------
Principal
OpenSource Connections
Site: http://www.opensourceconnections.com
Blog: http://blog.opensourceconnections.com
Cell: 1-434-466-1467

Larry Karnowski

2007-Apr-02 19:10 UTC

head link

[iCalendar-devel] Handling start and duration but no end for Events

Eric,
Could you incorporate both into the parser with a "lenient" flag?  I
can see both uses, but I would think the "happy path" of leniency
would suit most users better.

Larry

On 4/2/07, Eric Pugh <epugh at opensourceconnections.com>
wrote:> I''ve been going over this in my mind...  If you assume that the
> iCalendar tool is purely a "parser" then maybe it works the way
you
> would expect, returning nil for the end, instead of figuring it out.
> Because that is what the "parsed" data says.  However, if you
think
> there should be some handholding from the parser, or that you have
> two layers, the low level data and higher level user objects, then
> the higher level user objects should handle this then!
>
> I think I may just add a layer to my app that adds those sorts of
> higher level "convenience" methods.  argh...
>
> Eric Pugh
>
>
>
>
> On Apr 2, 2007, at 1:39 PM, Rob Kaufman wrote:
>
> > According to the icalendar spec, you must specify EITHER duration or
> > end, so it would make a lot of since for setting duration to
> > implicitly set end in the parser and vis-versa.  You are correct that
> > the parser does not currently handle the case where there is no end.
> >
> > Rob Kaufman
> >
> > On 3/30/07, Eric Pugh <epugh at opensourceconnections.com>
wrote:
> >> Hi all,
> >>
> >> I''ve got an event that looks like:
> >>
> >> BEGIN:VEVENT
> >> DTSTART;TZID=US/Eastern:20070402T140000
> >> SUMMARY:Call Robert
> >> UID:A11B2175-8082-4839-B253-74D1A6CACBA9
> >> SEQUENCE:4
> >> DTSTAMP:20070329T150439Z
> >> DESCRIPTION:Call to find out about bringing in Window guys......
> >> \n\n4
> >> 34-962-7950
> >> DURATION:PT1H
> >> BEGIN:VALARM
> >> ACTION:AUDIO
> >> TRIGGER:-PT15M
> >> X-WR-ALARMUID:76466515-A5C5-41C1-AECF-BF8C8BF972E0
> >> X-ICF-AUTOALARM:TRUE
> >> ATTACH;VALUE=URI:Basso
> >> END:VALARM
> >> END:VEVENT
> >>
> >> It has a start time, but no end time.  However, it does have a
> >> duration of PT1H.   My app is failing cause I have no end time.
> >> Should the iCalendar parser handle the fact that the end time
isn''t
> >> definined, and supply it based on the start time + duration?  Or
is
> >> this the responsibility of the user of the parser???
> >>
> >> I''m asking more from an understanding point of view? 
Seeing if I
> >> should patch icalendar parser or deal with it in my code.
> >>
> >> Eric
> >>
> >>
> >> -------------------------------------------------------
> >> Principal
> >> OpenSource Connections
> >> Site: http://www.opensourceconnections.com
> >> Blog: http://blog.opensourceconnections.com
> >> Cell: 1-434-466-1467
> >>
> >>
> >>
> >>
> >> _______________________________________________
> >> icalendar-devel mailing list
> >> icalendar-devel at rubyforge.org
> >> http://rubyforge.org/mailman/listinfo/icalendar-devel
> >>
> > _______________________________________________
> > icalendar-devel mailing list
> > icalendar-devel at rubyforge.org
> > http://rubyforge.org/mailman/listinfo/icalendar-devel
>
> -------------------------------------------------------
> Principal
> OpenSource Connections
> Site: http://www.opensourceconnections.com
> Blog: http://blog.opensourceconnections.com
> Cell: 1-434-466-1467
>
>
>
>
> _______________________________________________
> icalendar-devel mailing list
> icalendar-devel at rubyforge.org
> http://rubyforge.org/mailman/listinfo/icalendar-devel
>

Eric Pugh

2007-Apr-03 19:17 UTC

head link

[iCalendar-devel] Handling start and duration but no end for Events

I don''t have commit privileges on the underlying icalendar project,  
so right now I am trying to not change anything there, I''ll probably  
be playing around with layering on other stuff...

If you are interested, monitor novo.rubyforge.org, and look at  
"sync_gcal.rb" script..   It''s all a bit icky, unorganized,
but I''m
learning a lot out of this project.

I do like the "lenient" idea!

I discoved in "parser.rb" that the developer didn''t know how
to parse
duration which is in an odd standard formation.  However, turns out  
the the Vpim::Calendar project can handle it!  gem install vpim and  
run this unit test:

   # Test that Vpim library will do the duration conversion we need!
   def test_vpim_library
     result = Vpim::Icalendar.decode_duration(''PT1H'')
     assert_equal 3600, result

     result = Vpim::Icalendar.decode_duration(''PT2H10M'')
     assert_equal 7800, result

   end

I''ll try and use this, and then layer in populating the end method....

ERic


On Apr 2, 2007, at 3:10 PM, Larry Karnowski wrote:
> Eric,
> Could you incorporate both into the parser with a "lenient" flag?
I
> can see both uses, but I would think the "happy path" of leniency
> would suit most users better.
>
> Larry
>
> On 4/2/07, Eric Pugh <epugh at opensourceconnections.com> wrote:
>> I''ve been going over this in my mind...  If you assume that
the
>> iCalendar tool is purely a "parser" then maybe it works the
way you
>> would expect, returning nil for the end, instead of figuring it out.
>> Because that is what the "parsed" data says.  However, if you
think
>> there should be some handholding from the parser, or that you have
>> two layers, the low level data and higher level user objects, then
>> the higher level user objects should handle this then!
>>
>> I think I may just add a layer to my app that adds those sorts of
>> higher level "convenience" methods.  argh...
>>
>> Eric Pugh
>>
>>
>>
>>
>> On Apr 2, 2007, at 1:39 PM, Rob Kaufman wrote:
>>
>>> According to the icalendar spec, you must specify EITHER duration
or
>>> end, so it would make a lot of since for setting duration to
>>> implicitly set end in the parser and vis-versa.  You are correct  
>>> that
>>> the parser does not currently handle the case where there is no
end.
>>>
>>> Rob Kaufman
>>>
>>> On 3/30/07, Eric Pugh <epugh at opensourceconnections.com>
wrote:
>>>> Hi all,
>>>>
>>>> I''ve got an event that looks like:
>>>>
>>>> BEGIN:VEVENT
>>>> DTSTART;TZID=US/Eastern:20070402T140000
>>>> SUMMARY:Call Robert
>>>> UID:A11B2175-8082-4839-B253-74D1A6CACBA9
>>>> SEQUENCE:4
>>>> DTSTAMP:20070329T150439Z
>>>> DESCRIPTION:Call to find out about bringing in Window
guys......
>>>> \n\n4
>>>> 34-962-7950
>>>> DURATION:PT1H
>>>> BEGIN:VALARM
>>>> ACTION:AUDIO
>>>> TRIGGER:-PT15M
>>>> X-WR-ALARMUID:76466515-A5C5-41C1-AECF-BF8C8BF972E0
>>>> X-ICF-AUTOALARM:TRUE
>>>> ATTACH;VALUE=URI:Basso
>>>> END:VALARM
>>>> END:VEVENT
>>>>
>>>> It has a start time, but no end time.  However, it does have a
>>>> duration of PT1H.   My app is failing cause I have no end time.
>>>> Should the iCalendar parser handle the fact that the end time
isn''t
>>>> definined, and supply it based on the start time + duration? 
Or is
>>>> this the responsibility of the user of the parser???
>>>>
>>>> I''m asking more from an understanding point of view? 
Seeing if I
>>>> should patch icalendar parser or deal with it in my code.
>>>>
>>>> Eric
>>>>
>>>>
>>>> -------------------------------------------------------
>>>> Principal
>>>> OpenSource Connections
>>>> Site: http://www.opensourceconnections.com
>>>> Blog: http://blog.opensourceconnections.com
>>>> Cell: 1-434-466-1467
>>>>
>>>>
>>>>
>>>>
>>>> _______________________________________________
>>>> icalendar-devel mailing list
>>>> icalendar-devel at rubyforge.org
>>>> http://rubyforge.org/mailman/listinfo/icalendar-devel
>>>>
>>> _______________________________________________
>>> icalendar-devel mailing list
>>> icalendar-devel at rubyforge.org
>>> http://rubyforge.org/mailman/listinfo/icalendar-devel
>>
>> -------------------------------------------------------
>> Principal
>> OpenSource Connections
>> Site: http://www.opensourceconnections.com
>> Blog: http://blog.opensourceconnections.com
>> Cell: 1-434-466-1467
>>
>>
>>
>>
>> _______________________________________________
>> icalendar-devel mailing list
>> icalendar-devel at rubyforge.org
>> http://rubyforge.org/mailman/listinfo/icalendar-devel
>>
> _______________________________________________
> icalendar-devel mailing list
> icalendar-devel at rubyforge.org
> http://rubyforge.org/mailman/listinfo/icalendar-devel
-------------------------------------------------------
Principal
OpenSource Connections
Site: http://www.opensourceconnections.com
Blog: http://blog.opensourceconnections.com
Cell: 1-434-466-1467

Jeff Rose

2007-Apr-03 23:22 UTC

head link

[iCalendar-devel] Handling start and duration but no end for Events

Eric Pugh wrote:> I don''t have commit privileges on the underlying icalendar
project,
> so right now I am trying to not change anything there, I''ll
probably
> be playing around with layering on other stuff...
Please feel free to propose changes to the library and/or submit patches 
to the list.  I''m using git for the repository, so I can give out the 
URL so people can grab the latest source and patch locally if you are 
interested in doing that.
> I discoved in "parser.rb" that the developer didn''t know
how to parse
> duration which is in an odd standard formation. 
What do you mean odd formation?  If you can post an example of a 
calendar that breaks the parser I''d like to fix any problems.
>> On 4/2/07, Eric Pugh <epugh at opensourceconnections.com> wrote:
>>> I''ve been going over this in my mind...  If you assume
that the
>>> iCalendar tool is purely a "parser" then maybe it works
the way you
>>> would expect, returning nil for the end, instead of figuring it
out.
>>> Because that is what the "parsed" data says.  However, if
you think
>>> there should be some handholding from the parser, or that you have
>>> two layers, the low level data and higher level user objects, then
>>> the higher level user objects should handle this then!
You are very correct, but my hope is that we can add helpful bits and 
pieces like this over time to make it easier to use.  It ends up being 
mostly policy decisions about how things should work, but we should be 
able to come to consensus on what is reasonable for most of these cases.
>>>>> It has a start time, but no end time.  However, it does
have a
>>>>> duration of PT1H.   My app is failing cause I have no end
time.
>>>>> Should the iCalendar parser handle the fact that the end
time isn''t
>>>>> definined, and supply it based on the start time +
duration?  Or is
>>>>> this the responsibility of the user of the parser???
In this type of situation, what do you guys think about having the 
library compute whichever property is missing (dtend or duration), and 
then when writing out just always write the end time?  If it seemed 
necessary maybe there could be an option for writing duration instead...

-Jeff

icalendar devel - Mar 2007 - Handling start and duration but no end for Events

[iCalendar-devel] Handling start and duration but no end for Events

[iCalendar-devel] Handling start and duration but no end for Events

[iCalendar-devel] Handling start and duration but no end for Events

[iCalendar-devel] Handling start and duration but no end for Events

[iCalendar-devel] Handling start and duration but no end for Events

[iCalendar-devel] Handling start and duration but no end for Events