cron

cron is a Go library that parses a cron expression and outputs a human readable description of the cron schedule.
For example, given the expression "*/5 * * * *" it will output "Every 5 minutes".

Translated to Go from cron-expression-descriptor (C#) via cRonstrue (Javascript).
Original Author & Credit: Brady Holt (http://www.geekytidbits.com).

Features

• Zero dependencies
• Supports all cron expression special characters including * / , - ? L W, #
• Supports 5, 6 (w/ seconds or year), or 7 (w/ seconds and year) part cron expressions
• Supports Quartz Job Scheduler cron expressions
• i18n support with 25 languages

Installation

cron module can be used with Go >= 1.13.

go get github.com/lnquy/cron

Usage

// Init with default EN locale
exprDesc, _ := cron.NewDescriptor()

desc, _ := exprDesc.ToDescription("* * * * *", cron.Locale_en)
// "Every minute" 

desc, _ := exprDesc.ToDescription("0 23 ? * MON-FRI", cron.Locale_en)
// "At 11:00 PM, Monday through Friday" 

desc, _ := exprDesc.ToDescription("23 14 * * SUN#2", cron.Locale_en)
// "At 02:23 PM, on the second Sunday of the month"

// Init with custom configs
exprDesc, _ := cron.NewDescriptor(
    cron.Use24HourTimeFormat(true),
    cron.DayOfWeekStartsAtOne(true),
    cron.Verbose(true),
    cron.SetLogger(log.New(os.Stdout, "cron: ", 0)),
    cron.SetLocales(cron.Locale_en, cron.Locale_fr),
)

For more usage examples, including a demonstration of how cRonstrue can handle some very complex cron expressions, you can reference the unit tests or the example codes.

Demo

[...]

i18n

To use the i18n support, you must configure the locales when create a new ExpressionDescriptor via SetLocales() option.

exprDesc, _ := cron.NewDescriptor(
    cron.SetLocales(cron.Locale_en, cron.Locale_es, cron.Locale_fr),
)
// or load all cron.LocaleAll
exprDesc, _ := cron.NewDescriptor(cron.SetLocales(cron.LocaleAll))

desc, _ := exprDesc.ToDescription("* * * * *", cron.Locale_fr)
// Toutes les minutes

By default, ExpressionDescriptor always load the Locale_en. If you passes an unregistered locale into ToDescription() function, the result will be returned in English.

Supported Locales

• en - English
• cs - Czech
• es - Spanish
• da - Danish
• de - German
• fi - Finnish
• fr - French
• fa - Farsi
• he - Hebrew
• it - Italian
• ja - Japanese
• ko - Korean
• nb - Norwegian
• nl - Dutch
• pl - Polish
• pt_BR - Portuguese (Brazil)
• ro - Romanian
• ru - Russian
• sk - Slovakian
• sl - Slovenian
• sw - Swahili
• sv - Swedish
• tr - Turkish
• uk - Ukrainian
• zh_CN - Chinese (Simplified)
• zh_TW - Chinese (Traditional)
  [TODO]

Project status

• Port 1-1 code from cRonstrue Javascript
• Port and pass all test cases from cRonstrue
• i18n for 25 languages
• Test cases i18n
• Fix i18n issues of FA, HE, RO, RU, UK, ZH_CN and ZH_TW
• Performance improvement
• Release v1.0

License

This project is under the MIT License. See the LICENSE file for the full license text.