Task Scheduler in Go (Golang): cron, gocron and robfig/cron

Task Scheduler in Go (Golang): cron, gocron and robfig/cron

A task scheduler is an indispensable tool for automating periodic operations in applications: from cache cleaning and sending notifications to launching background data processors. In the Go (Golang) ecosystem, there are several popular libraries for implementing cron-like behavior. In this article, we will look at three main approaches: the built-in cron package, the lightweight gocron, and the de facto standard robfig/cron.

1. Built-in cron package (experimental)

Starting with Go 1.19, the standard library introduced an experimental cron package in golang.org/x/exp/cron. It provides basic functionality for running tasks on a schedule. However, in practice it is rarely used due to limited functionality and lack of support for complex cron expressions (e.g., with seconds).

package main

import (    "context"    "fmt"    "golang.org/x/exp/cron"    "time")

func main() {    sched := cron.New()    // Run every 10 seconds    sched.Add("*/10 * * * * *", func() {        fmt.Println("Task executed:", time.Now())    })    sched.Start()    time.Sleep(30 * time.Second)    sched.Stop()}

2. robfig/cron library — the gold standard

The github.com/robfig/cron/v3 library is the most popular and mature implementation of a task scheduler in Go. It supports:

• Standard cron expressions (5 fields) with an optional seconds field
• Predefined schedules: @yearly, @monthly, @weekly, @daily, @hourly
• Intervals: @every 5m (every 5 minutes)
• Time zones
• Panic handling via a Recovery logger
• Flexible logging system through the Logger interface

Installation

go get github.com/robfig/cron/v3

Basic example

package main

import (    "fmt"    "github.com/robfig/cron/v3"    "time")

func main() {    c := cron.New(cron.WithSeconds()) // Enable seconds support

    // Every minute at 30 seconds    c.AddFunc("30 * * * * *", func() {        fmt.Println("Every minute at 30 seconds:", time.Now().Format("15:04:05"))    })

    // Every day at 8:00 AM    c.AddFunc("0 0 8 * * *", func() {        fmt.Println("Daily at 8:00")    })

    // Every 2 hours    c.AddFunc("@every 2h", func() {        fmt.Println("Every 2 hours")    })

    // Monday at 9:30    c.AddFunc("30 9 * * 1", func() {        fmt.Println("Every Monday at 9:30")    })

    c.Start()    defer c.Stop()

    // Wait 1 minute to see execution    time.Sleep(70 * time.Second)}

Cron expression syntax in robfig/cron

A standard expression consists of 5 fields (minutes, hours, day of month, month, day of week). When the cron.WithSeconds() option is enabled, a sixth field — seconds (0-59) — is added.

• * — any value
• */5 — every 5 units
• 1,15,30 — specific values
• 1-10 — range
• L — last (e.g., last day of the month)

3. gocron library — simplicity and readability

github.com/go-co-op/gocron offers a higher-level, fluent interface for creating schedules. It is ideal if you do not need complex cron expressions and simple intervals are sufficient.

Installation

go get github.com/go-co-op/gocron/v2

Usage example

package main

import (    "fmt"