RE: Epics Archiver Appliance requests and DST/Timezones

["Manoussakis, Adamandios via Tech-talk" <tech-talk@aps.anl.gov>]

Thank you all for the suggestions, I think I have a better understanding now. 

-----Original Message-----
From: Michael Davidsaver <mdavidsaver@gmail.com> 
Sent: Wednesday, November 16, 2022 9:06 PM
To: Manoussakis, Adamandios <manoussakis1@llnl.gov>
Cc: Ralph Lange <ralph.lange@gmx.de>; EPICS Tech Talk <tech-talk@aps.anl.gov>; Jemian, Pete R. <jemian@anl.gov>; Abdalla Ahmad <abdalla.ahmad@sesame.org.jo>
Subject: Re: Epics Archiver Appliance requests and DST/Timezones

On 11/15/22 11:37, Manoussakis, Adamandios via Tech-talk wrote:
> 2012-012-27*T18:00:00.000-000Z *or have the offset in the request 2012-012-27*T10:00:00.000-800Z. *But either way it looks like I need to account timezone/dst for the request, unless I am misunderstanding something horribly.

When providing an offset, leave off the trailing "Z".

On a Linux host, run:

> $ date -Isec
> 2022-11-16T20:50:55-08:00

to see an example for your currently configured place and time.

As others have said, I think you would do better to delegate this conversion to a timezone database, as accessed through your API of choice, and send only UTC times over the wire.

fyi. On Linux, it is easy enough to override timezone on a per-process basis with the $TZ environment variable.

> $ TZ=Brazil/East date -Isec
> 2022-11-17T01:55:20-03:00

cf. /usr/share/zoneinfo/ and "man tzset"