Expand description
Chrono-TZ
Chrono-TZ
is a library that provides implementors of the
TimeZone
trait for chrono
. The
impls are generated by a build script using the IANA database
and zoneinfo_parse
.
Examples
Create a time in one timezone and convert it to UTC
use chrono::{TimeZone, Utc};
use chrono_tz::US::Pacific;
let pacific_time = Pacific.ymd(1990, 5, 6).and_hms(12, 30, 45);
let utc_time = pacific_time.with_timezone(&Utc);
assert_eq!(utc_time, Utc.ymd(1990, 5, 6).and_hms(19, 30, 45));
Create a naive datetime and convert it to a timezone-aware datetime
use chrono::{TimeZone, NaiveDate};
use chrono_tz::Africa::Johannesburg;
let naive_dt = NaiveDate::from_ymd(2038, 1, 19).and_hms(3, 14, 08);
let tz_aware = Johannesburg.from_local_datetime(&naive_dt).unwrap();
assert_eq!(tz_aware.to_string(), "2038-01-19 03:14:08 SAST");
London and New York change their clocks on different days in March so only have a 4-hour difference on certain days.
use chrono::TimeZone;
use chrono_tz::Europe::London;
use chrono_tz::America::New_York;
let london_time = London.ymd(2016, 3, 18).and_hms(3, 0, 0);
let ny_time = london_time.with_timezone(&New_York);
assert_eq!(ny_time, New_York.ymd(2016, 3, 17).and_hms(23, 0, 0));
Adding 24 hours across a daylight savings change causes a change in local time
use chrono::{TimeZone, Duration};
use chrono_tz::Europe::London;
let dt = London.ymd(2016, 10, 29).and_hms(12, 0, 0);
let later = dt + Duration::hours(24);
assert_eq!(later, London.ymd(2016, 10, 30).and_hms(11, 0, 0));
And of course you can always convert a local time to a unix timestamp
use chrono::TimeZone;
use chrono_tz::Asia::Kolkata;
let dt = Kolkata.ymd(2000, 1, 1).and_hms(0, 0, 0);
let timestamp = dt.timestamp();
assert_eq!(timestamp, 946665000);
Pretty-printing a string will use the correct abbreviation for the timezone
use chrono::TimeZone;
use chrono_tz::Europe::London;
let dt = London.ymd(2016, 5, 10).and_hms(12, 0, 0);
assert_eq!(dt.to_string(), "2016-05-10 12:00:00 BST");
assert_eq!(dt.to_rfc3339(), "2016-05-10T12:00:00+01:00");
You can convert a timezone string to a timezone using the FromStr trait
use chrono::TimeZone;
use chrono_tz::Tz;
use chrono_tz::UTC;
let tz: Tz = "Antarctica/South_Pole".parse().unwrap();
let dt = tz.ymd(2016, 10, 22).and_hms(12, 0, 0);
let utc = dt.with_timezone(&UTC);
assert_eq!(utc.to_string(), "2016-10-21 23:00:00 UTC");
If you need to iterate over all variants you can use the TZ_VARIANTS array
use chrono_tz::{TZ_VARIANTS, Tz};
assert!(TZ_VARIANTS.iter().any(|v| *v == Tz::UTC));