Time - Speaker Deck

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Time Dirkjan Bussink! @dbussink

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Time is hard

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Basics

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Timezones

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http://momentjs.com/

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http://momentjs.com/

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Storing

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UTC

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Why?

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2014-10-26 02:34

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A bit more! complicated

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Group! by date

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Who’s date?

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http://pellepim.bitbucket.org/jstz/

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Calculations

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Perspective

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UTC loses data

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UTC + offset

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2014-08-19 16:12:50 +0200

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Time as a feature

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Calendars

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DST

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amsterdam = ActiveSupport::TimeZone["Europe/Amsterdam"] time = amsterdam.parse("2014-08-19 17:15") => Tue, 19 Aug 2014 17:15:00 CEST +02:00

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sydney = ActiveSupport::TimeZone[“Australia/Sydney"] ! time => Tue, 19 Aug 2014 17:15:00 CEST +02:00 time.in_time_zone(sydney) => Wed, 20 Aug 2014 01:15:00 EST +10:00

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later = time + 6.months => Thu, 19 Feb 2015 17:15:00 CET +01:00 ! later.in_time_zone(sydney) => Fri, 20 Feb 2015 03:15:00 EST +11:00

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Our recurring meeting! just moved 2 hours!

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UTC + offset! isn’t good enough

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Time & time zone Europe/Amsterdam Tue, 19 Aug 2014 17:15:00 CEST +02:00

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Time tracking

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Check in & check out

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125% 22:00 00:00 150% Break 150% 01:00 01:30 06:00

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DST

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125% 150% Break 150% 01:30 02:00 02:59 02:00 03:00

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9 hours from 22:00 until 06:00

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Very speciﬁc! storage format

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Day!! ! ! ! ! ! ! 2014-10-26! Start!! ! ! ! ! ! 79200!! ! ! End!! ! ! ! ! ! ! 108000! Duration!! ! 32400