Handling Daylight Saving Time

Question

In Python 3.x, I want to capture current time along with its timezone and then convert it into Unix timestamp and sent to a server.

I have tried various libraries like pytz, arrow, moment, pendulum, but I am not sure how to deal with daylight saving time (DST). Currently, I am using time.tzname to get timezone information but it specifically showing India in DST. In reality India never follows DST.

Unix timestamps are always UTC based. Thus, if you just want the current time as a Unix timestamp, just get the current UTC time directly. No need to involve time zones or DST. See https://stackoverflow.com/q/16755394/634824 — Matt Johnson-Pint, Aug 09 '19 at 14:10

Csaba Németh · Answer 1 · 2019-08-09T16:19:32.450

1

The library pytz should work pretty well. You need to use the function dst() from that library to check if a timezone is under daylight savings influence.

https://medium.com/@nqbao/python-timezone-and-daylight-savings-e511a0093d0

From the link above:

>>> import pytz
>>> pst = pytz.timezone("US/Pacific")
>>> pst.localize(datetime(2017, 10, 1)).dst()
datetime.timedelta(0, 3600)
>>> pst.localize(datetime(2017, 12, 1)).dst()
datetime.timedelta(0)

Understanding offset naive and offset aware date times will make your life much easier.

edited Aug 09 '19 at 16:19

answered Aug 08 '19 at 18:58

Csaba Németh

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1
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@Csaba_Nemeth Thanks for your input. Please edit your answer and quote the essential parts from the website you cited. It might also help, if you add a minimal working code snippet. – B--rian Aug 09 '19 at 08:30

score 0 · Accepted Answer · answered Dec 09 '20 at 17:08

This helped me in resolving the issue using time.tzname

    if time.tzname[1] is None or time.tzname[0] == time.tzname[1]:
        timezone = time.localtime().tm_zone
            # no DST
            timezone = time.tzname[0]
        else:

            # we're in DST
            timezone = time.tzname[1]

Handling Daylight Saving Time

2 Answers2