kennytm / tzfile Goto Github PK

this would enable more cases like accepting user provided timezone identifiers

Tz::named always loads its time zones from /usr/share/zoneinfo/, even if TZDIR is set. From what I can tell, glibc respects this variable.

This would be useful since NixOS uses a nonstandard time zone directory location (/etc/zoneinfo/ or /etc/static/zoneinfo/) which this library currently can't find.

Windows user here, is there a chance to use it?

According to https://www.freedesktop.org/software/systemd/man/localtime.html, if /etc/localtime is missing, the default UTC time zone should be used.
Currently, Tz::local() returns a No such file or directory error. It would be nice if Tz::local() defaults to parsing /usr/share/zoneinfo/UTC if /etc/localtime is not found.

Chrono's Serialize implementation uses Debug formatting for Serialize, and assumes that it will produce valid RFC 3339: https://docs.rs/chrono/0.4.19/src/chrono/datetime.rs.html#2066
https://docs.rs/chrono/0.4.19/src/chrono/datetime.rs.html#720

ArcTz's offset prints the time zone's name in Debug, not the offset, so DateTime serializes into an incorrect format.

For example:

use chrono::{DateTime, NaiveDate, TimeZone};
use serde::Serialize;
use tzfile::ArcTz;

#[derive(Debug, Serialize)]
pub struct Foo {
    pub date: DateTime<ArcTz>,
}

fn main() {
    let tz = ArcTz::named("Europe/Budapest").unwrap();
    let dt = tz.from_utc_datetime(&NaiveDate::from_ymd(2021, 3, 11).and_hms(17, 49, 32));
    println!("{:?}", dt.offset());
    let foo = Foo { date: dt };
    let j = serde_json::to_string(&foo).unwrap();
    println!("{}", j);
}

This prints {"date":"2021-03-11T18:49:32CET"}, which isn't valid RFC3339.

It would be nice to mirror the functionality from chrono_tz and, for example, make tzfile::Tz serializable.