How to get UTC Offset as integer

[bryaan]

How can I get the current UTC offset from tz"America/New_York" ?

[omus]

You can use access the offset of a specific ZonedDateTime via:

julia> using TimeZones

julia> now(tz"America/New_York").zone.offset
UTC-5/+1

julia> string(ans)
"-04:00"

If this is something you're just wanting to view for yourself you can do:

julia> show_next_transition(tz"America/New_York")
Transition Date:   2021-11-07
Local Time Change: 02:00 → 01:00 (Backward)
Offset Change:     UTC-5/+1 → UTC-5/+0
Transition From:   2021-11-07T01:59:59.999-04:00 (EDT)
Transition To:     2021-11-07T01:00:00.000-05:00 (EST)

Which shows the current offset in "Offset Change" as well as a other information.

[bryaan]

@omus Thank you! Can we add an int(timezoneawaretime) to make integer conversion easier?

[ericphanson]

It would be nice to have something like

function get_offset_seconds(zdt)
    offset = FixedTimeZone(zdt).offset
    return offset.dst + offset.std
end

as part of the API. The issue with the string version is that it will show as eg "EDT":

julia> zdt1 = ZonedDateTime(2014, 5, 30, 21, tz"America/New_York")
2014-05-30T21:00:00-04:00

julia> string(FixedTimeZone(zdt1))
"EDT"

[omus]

I do think we can support a nice way of extracting the offset information than we currently have. Some considerations we need to keep in mind:

• We can't generally extract an offset from a time zone alone. This is possible for FixedTimeZone types but VariableTimeZones require an instance in time to determine what the offset would be. This means you would probably get the offset from a ZonedDateTime.
• We would want to keep track of units so this function would likely output the type Second
• The offsets are comprised of the standard offset and the daylight saving time offset. Most users will care about the sum of these values but this does mean we probably shouldn't use convert here as the conversion isn't lossless.

[langestefan]

Completely agree with above comments. This required some googling, and I ended up here. +1

The offsets are comprised of the standard offset and the daylight saving time offset.

If I understand correctly, the 'standard' offset would be referred to as the Meridian offset. For my specific application I need this value to compute the Local Standard Time Meridian.

[omus]

The terminology used in TimeZones.jl is mainly based upon https://data.iana.org/time-zones/code/theory.html. In most cases uses want the standard offset and daylight saving offset added together.