Chrono-TZ 0.1.1
Chrono-TZ
is a library that provides implementors of the
TimeZone
trait for rust-chrono
. The
impls are generated by a build script using the IANA database
.
Usage
Put this in your Cargo.toml
:
[dependencies]
chrono = "0.2"
chrono-tz = "0.1"
Then you will need to write (in your crate root):
extern crate chrono;
extern crate chrono_tz;
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));
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");
Known Issues
The timezone info for Dushanbe is not parsed correctly by zoneinfo_parse
and so I have commented out a line from that file to work around it.
# Tajikistan
# From Shanks & Pottenger.
# Zone NAME GMTOFF RULES FORMAT [UNTIL]
Zone Asia/Dushanbe 4:35:12 - LMT 1924 May 2
5:00 - +05 1930 Jun 21
6:00 RussiaAsia +06/+07 1991 Mar 31 2:00s
# 5:00 1:00 +05/+06 1991 Sep 9 2:00s # FIXME: fails to parse
5:00 - +05
Strings cannot be parsed into appropriate datetimes currently, they can only be printed out. Chrono handles fixed offsets only for parsing.
Currently no rustc-serialize or serde support.