cron

Cron expression parsing and next-fire-time calculation with standard 5-field syntax, optional seconds, and descriptors.

Supported syntax

• Standard 5-field: minute hour day-of-month month day-of-week
• Optional 6-field: second minute hour day-of-month month day-of-week
• *, literal values, comma lists (1,3,5), ranges (1-5), steps (*/2, 1-10/3)
• 5L (last weekday of month), 15W (nearest weekday)
• Descriptors: @hourly, @daily, @every 10s, etc.

Key types

• Expression -- a parsed cron expression

Key functions

• Parse(expr) -- parse a cron expression string
• MustParse(expr) -- parse, panicking on error
• Expression.Next(t) -- compute the next fire time after t
• Expression.HasSeconds() / Expression.IsEvery() / Expression.EveryDuration()

Quick start

import (
    "time"
    "github.com/LingByte/ling-base/common/cron"
)

expr, err := cron.Parse("*/5 * * * *")
if err != nil {
    log.Fatal(err)
}
next := expr.Next(time.Now())
fmt.Println("next fire:", next)

// 6-field with seconds
expr2, _ := cron.Parse("0 */30 * * * *")

// Descriptor
expr3, _ := cron.Parse("@every 10s")

License

MIT