Astrolabe

Overview

Astrolabe is a date and time library for Rust which aims to be feature rich, lightweight (zero dependencies) and easy-to-use. It implements formatting, parsing and manipulating functions for date and time values.

Features

• Formatting and parsing with format strings based on Unicode Date Field Symbols
• RFC 3339 timestamp parsing and formatting
• Manipulation functions to add, subtract, set and clear date units
• Cron expression parser
• Timezone offset
• Local timezone on UNIX platforms
• Zero dependencies
• Serde serializing and deserializing (With feature flag serde)
• sqlx postgres encoding and decoding (With feature flag sqlx-postgres)

Examples

Basic

A basic example which demonstrates creating, formatting and manipulating a DateTime instance.

use astrolabe::{DateTime, TimeUtilities, Precision};

// Create a DateTime instance from year, month, and days (day of month)
let date_time = DateTime::from_ymd(2022, 5, 2).unwrap();

// Use the format function to freely format your DateTime instance
assert_eq!("2022/05/02", date_time.format("yyyy/MM/dd"));

// Create a new instance with a modified DateTime
// The previous instance is not modified and is still in scope
let modified_dt = date_time.add_hours(11).add_minutes(23);

assert_eq!("2022/05/02 11:23:00", modified_dt.format("yyyy/MM/dd HH:mm:ss"));
assert_eq!("2022-05-02T11:23:00Z", modified_dt.format_rfc3339(Precision::Seconds));

To see all implementations for the DateTime struct, check out it's documentation.

Local timezone (UNIX systems only)

Astrolabe can parse the timezone from /etc/localtime to get the local UTC offset. This only works on UNIX systems.

use astrolabe::{DateTime, Offset, OffsetUtilities, Precision};

// Equivalent to `DateTime::now().set_offset(Offset::Local)`
let now = DateTime::now_local();

// Prints for example:
// 2023-10-08T08:30:00+02:00
println!("{}", now.format_rfc3339(Precision::Seconds));
assert_eq!(Offset::Local, now.get_offset());

See Offset

CRON parsing

use astrolabe::CronSchedule;

// Every 5 minutes
let schedule = CronSchedule::parse("*/5 * * * *").unwrap();
for date in schedule.take(3) {
   println!("{}", date);
}
// Prints for example:
// 2022-05-02 16:15:00
// 2022-05-02 16:20:00
// 2022-05-02 16:25:00

// Every weekday at 10:00
let schedule = CronSchedule::parse("0 10 * * Mon-Fri").unwrap();
for date in schedule.take(3) {
   println!("{}", date.format("yyyy-MM-dd HH:mm:ss eeee"));
}
// Prints for example:
// 2022-05-03 10:00:00 Tuesday
// 2022-05-04 10:00:00 Wednesday
// 2022-05-05 10:00:00 Thursday

See CronSchedule

MSRV

This crate uses the Rust 2021 Edition and requires at least version 1.60. When using features that require third-party crates (serde or sqlx), please refer to their MSRV.

License

Licensed under either of

• Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)

at your option.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.