[kronolith] Date and Timezones..

[Simon Brereton]

On 9 January 2012 16:12, Michael J Rubinsky <mrubinsk at horde.org> wrote:
>
> Quoting Simon Brereton <simon.brereton at buongiorno.com>:
>
>> Hi
>>
>> I'm addressing this to Kronolith but for me it'a system-wide issue as
>> it affects sync as well.
>>
>> The specific issue is that I have a user complaining about an error -
>>
>> DateTime::_construct(): Failed to parse time string (-001-11-01) at
>> position 7 (-): Double timezone specificatio
>
>
> These errors are _probably_ not related to timezones at all. They are
> usually due to some non-standard or malformed datetime string being passed
> to DateTime's constructor (and it mistakes part of the string for a timezone
> specifier). Where do you see this? Creating an event from which interface?
>  If you can get a look at exactly where in the code and what the value is,
> we can try to help.

Creating an event in Kronolith by clicking on the day.  You'll have to
tell me where to look :)



>> when trying to create an appointment.
>>
>> More generally time zones are an issue that I can't get right.
>> Hopefully you can advise me how to fix this.
>>
>> The server is set to UTC. Most of the users are either UTC+1, GMT or
>> UTC-5.  What happens for the UTC-5 users (i.e. me) is that if I create
>> an all-day appointment or mark a contact with the a birthday), the
>> time is stored in UTC.  When this syncs to my device with activesync,
>> it shows up at 7pm on the preceding day even though in my Horde
>> Preferences I have my time-zone set to America/New York (i.e. UTC-5).
>> If I then go into the device and edit the time-zone to be EST then
>> when I log back into Horde, the appointment is now pushed over into a
>> second day.  I illustrate with a real-world numbers example...
>>
>> I have a contact with a birthday on the 11th of January.  In Horde, I
>> create the all-day appointment on the 11th (repeating yearly, etc).
>> The phone shows the appointment as starting on the 10th at 7pm (even
>> though it's all-day - i.e. it shows up at the top of both the 10th and
>> the 11th and I get the reminder (set to 5 minutes) at 6.55pm EST).  If
>> I then edit the appointment to be EST on the device this makes the
>> appointment correctly show up on the device only on the 11th (with the
>> reminder at 11.55pm on the 10th) but when I log into Horde the
>> appointment is now showing from the 11/01/2012 to 12/01/2012 and
>> appears in both days.
>>
>> Similarly the GMT and UTC+1 users have the reverse problem...
>>
>> They create the appointment but then appointment reminder is either
>> late or the appointment shows on the day AFTER.  If they edit it on
>> the device to be GMT (or UTC+1) then the appointment shows correctly
>> on the device but when they go back to Horde the appointment is now
>> showing on day before in Horde.
>>
>> To be clear, I don't think this is a Horde issue - I'm perfectly
>> willing to believe I've set something up incorrectly, but I'd be
>> grateful is someone could say what.
>>
>> Regular (i.e. 1 hour/12 hour/30 min) appointments don't have this issue.
>> But if it isn't me, then I think the solution would be as in other
>> PIMs to be able to set the time-zone for the appointments/contacts.
>
>
> First of all, I will assume you are running a released version. The
> 'develop' branch (which will be released as the x.1 releases) has the
> ability to set individual event's timezones. Though, in the examples you
> cite above, this feature really wouldn't help you. I am also going to assume
> that you have verified that all of your PEAR packages are up to date -
> espeically Horde_Date, Kronolith and Horde_ActiveSync. There were some
> not-so-long-ago fixes made related to datetime handling.

I have all but the most recent update..  I'll update and see what happens.


> I'm not entirely sure what may be causing the issues you are seeing so I
> will describe how it is *supposed* to work and we can go from there. For
> support across timezones you *must* store your events as UTC in the
> database. Otherwise, the events are "floating" and will always appear at the
> same physical time regardless of timezone. Let's assume your timezone in
> Horde is set to America/New_York. You create an event in Horde. Internally,
> the event is converted to UTC time and stored in the database. When you sync
> the event via ActiveSync, it is the UTC value that is sent to the device,
> along with some timezone inforation. The TZ information that is sent from
> Horde is actually only used by the device if it is a recurring event that
> crosses a DST transition. Otherwise, the datetime is converted to the
> device's configured timezone. So, for example, an event created at 5:00PM in
> a UTC-5 timezone would get stored in the database (and sent to the device)
> as 10:00PM on the same day. The device receives this value and (assuming the
> device's timezone is set to UTC-5), converts it back to 5:00PM.  In this
> scenerio it doesn't matter what timezone the physical server is set to. The
> important bits are the timezone prefs on both Horde and the device.

Yes, this was mentioned when I first moved the server to UTC - and I
ran the script to convert all appointment times to UTC.  I haven't
checked, but I assume that's still the case.

> Now, that being said, seeing how your "1 hour/12 Hour/30min" appointments
> *do* come across correctly, it sounds like there might be an issue with
> either how your device handles all day events or there is a bug in how Horde
> handles these events.
>
> I'm also unclear as to what is going on when you are setting the event to be
> UTC-5 on your device manually. You said your Horde prefs are UTC-5, right?
> So the event was converted from UTC-5 to UTC in Horde and then sent to the
> device. The device should convert this to it's configured timezone. Assuming
> your device is configured for the timezone you are in, it should have
> converted to UTC-5 on it's own. As explained above, the event is sent as UTC
> to the device and then converted to the device's timezone. It sounds to me
> as if the device either doesn't offer proper timezone support or the
> timezone is not set correctly. What timezone does the event show in prior to
> editing it?

On my device (which is definitely UTC-5) it always offers either GMT or CET.

Simon