1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 <2022> 2023 2024 2025 | Index | 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 <2022> 2023 2024 2025 |
<== Date ==> | <== Thread ==> |
---|
Subject: | RE: Epics Archiver Appliance requests and DST/Timezones |
From: | "Manoussakis, Adamandios via Tech-talk" <tech-talk at aps.anl.gov> |
To: | Ralph Lange <ralph.lange at gmx.de>, EPICS Tech Talk <tech-talk at aps.anl.gov> |
Date: | Tue, 15 Nov 2022 19:37:58 +0000 |
Hi Abdalla/Ralph, Thanks for the responses and sorry for my naïve questions as this has been confusing for me. Ralph just to clarify the part about “clients should formulate their requests in UTC”, that means that I do need to account for the proper offset based off my time zone (and DST) to get the proper UTC timestamp correct for the URL request?
I think that matches what Abdalla had mentioned about the client application grabbing the offset as well. Example If I have a PV that is stored at 10am PST, the IOC time stamp stores it at UTC but it has to get the offset from the system clock to go from PST to UTC right (-8 in this case to get to UTC)? Now if I want to get the PV in the archiver
that was stored at 10am PST, it seems I have two choices I either request it in UTC (had to add in the offset 10am + 8) 2012-012-27T18:00:00.000-000Z or have the offset in the request 2012-012-27T10:00:00.000-800Z.
But either way it looks like I need to account timezone/dst for the request, unless I am misunderstanding something horribly. Thanks, Adam From: Tech-talk <tech-talk-bounces at aps.anl.gov> On Behalf Of
Ralph Lange via Tech-talk I agree with Abdalla. The idea is: IOC timestamps are UTC (= no timezone, no DST). The archive engine puts those IOC timestamps into the archive, without changing them. Clients should formulate their requests in UTC. The returned data will have the UTC timestamps from the archive. In other words: The times are in UTC; any conversion to local time needs to happen at the client. Cheers, |