rfyiamcool / cronlib

🐤 🐤 🐤 golang crontab scheduler

cronlib

Cronlib is easy golang crontab library, support parse crontab and schedule cron jobs.

cron_parser.go import https://github.com/robfig/cron/blob/master/parser.go, thank @robfig

Feature

• thread safe
• add try catch mode
• dynamic modify job cron
• dynamic add job
• stop service job
• add Wait method for waiting all job exit
• async & sync mode

Usage

see more example

quick run

package main

import (
	"log"

	"github.com/rfyiamcool/cronlib"
)

var (
	cron = cronlib.New()
)

func main() {
	handleClean()
	go start()

	// cron already start, dynamic add job
	handleBackup()

	select {}
}

func start() {
	cron.Start()
	cron.Wait()
}

func handleClean() {
	job, err := cronlib.NewJobModel(
		"*/5 * * * * *",
		func() {
			pstdout("do clean gc action")
		},
	)
	if err != nil {
		panic(err.Error())
	}

	err = cron.Register("clean", job)
	if err != nil {
		panic(err.Error())
	}
}

func handleBackup() {
	job, err := cronlib.NewJobModel(
		"*/5 * * * * *",
		func() {
			pstdout("do backup action")
		},
	)
	if err != nil {
		panic(err.Error())
	}

	err = cron.DynamicRegister("backup", job)
	if err != nil {
		panic(err.Error())
	}
}

func pstdout(srv string) {
	log.Println(srv)
}

set job attr

open async mode and try catch mode

func run() error {
	cron := cronlib.New()

	// set async mode
	job, err = cronlib.NewJobModel(
		"0 * * * * *",
		func(),
		cronlib.AsyncMode(),
		cronlib.TryCatchMode(),
	)

	...
}

other method

func run() error {
	cron := cronlib.New()

	// set async mode
	job, err = cronlib.NewJobModel(
		"0 * * * * *",
		func(),
	)

	...

	job.SetTryCatch(cronlib.OnMode)
	job.SetAsyncMode(cronlib.OnMode)

	...
}

stop job

cron := cronlib.New()
...
cron.StopService(srvName)

update job

spec := "*/3 * * * * *"
srv := "risk.scan.total.5s.to.3s"

job, _ := cronlib.NewJobModel(
	spec,
	func() {
		stdout(srv, spec)
	},
)

err := cron.UpdateJobModel(srv, job)
...

Example

package main

// test for crontab spec

import (
	"log"
	"time"

	"github.com/rfyiamcool/cronlib"
)

func main() {
	cron := cronlib.New()

	specList := map[string]string{
		"risk.scan.total.1s":       "*/1 * * * * *",
		"risk.scan.total.2s":       "*/2 * * * * *",
		"risk.scan.total.3s":       "*/3 * * * * *",
		"risk.scan.total.4s":       "*/4 * * * * *",
		"risk.scan.total.5s.to.3s": "*/5 * * * * *",
	}

	for srv, spec := range specList {
		tspec := spec // copy
		ssrv := srv   // copy
		job, err := cronlib.NewJobModel(
			spec,
			func() {
				stdout(ssrv, tspec)
			},
		)
		if err != nil {
			panic(err.Error())
		}

		err = cron.Register(srv, job)
		if err != nil {
			panic(err.Error())
		}
	}

	// update test
	time.AfterFunc(10*time.Second, func() {
		spec := "*/3 * * * * *"
		srv := "risk.scan.total.5s.to.3s"
		log.Println("reset 5s to 3s", srv)
		job, _ := cronlib.NewJobModel(
			spec,
			func() {
				stdout(srv, spec)
			},
		)
		cron.UpdateJobModel(srv, job)
		log.Println("reset finish", srv)

	})

	// kill test
	time.AfterFunc(3*time.Second, func() {

		srv := "risk.scan.total.1s"
		log.Println("stoping", srv)
		cron.StopService(srv)
		log.Println("stop finish", srv)

	})

	time.AfterFunc(11*time.Second, func() {

		srvPrefix := "risk"
		log.Println("stoping srv prefix", srvPrefix)
		cron.StopServicePrefix(srvPrefix)

	})

	cron.Start()
	cron.Wait()
}

func stdout(srv, spec string) {
	log.Println(srv, spec)
}

Time Format Usage:

cronlib has second field, cronlibs contains six fields, first field is second than linux crontab

every 2 seconds

*/2 * * * * *

every hour on the half hour

0 30 * * * *

detail field desc

Field name   | Mandatory? | Allowed values  | Allowed special characters
----------   | ---------- | --------------  | --------------------------
Seconds      | Yes        | 0-59            | * / , -
Minutes      | Yes        | 0-59            | * / , -
Hours        | Yes        | 0-23            | * / , -
Day of month | Yes        | 1-31            | * / , - ?
Month        | Yes        | 1-12 or JAN-DEC | * / , -
Day of week  | Yes        | 0-6 or SUN-SAT  | * / , - ?

cron parse doc: https://github.com/robfig/cron

cronlib's Issues

gracefull exit?

It looks like when call CronSchduler.Stop() ,some job may still running

调度器似乎有 DATA RACE?

==================
WARNING: DATA RACE
Write at 0x00c000152b38 by goroutine 101:
  github.com/rfyiamcool/cronlib.(*CronSchduler).UnRegister()
      /home/espush/golang/pkg/mod/github.com/rfyiamcool/[email protected]/scheduler.go:435 +0x102
  gateway/modules/crontab.RemoveCronItem()
      /home/espush/light/gateway/modules/crontab/entry.go:60 +0xbc
... ... ... ... more stack.
  github.com/rfyiamcool/cronlib.(*JobModel).run.func1()
      /home/espush/golang/pkg/mod/github.com/rfyiamcool/[email protected]/scheduler.go:349 +0x35c

Previous read at 0x00c000152b38 by goroutine 91:
  github.com/rfyiamcool/cronlib.(*JobModel).run()
      /home/espush/golang/pkg/mod/github.com/rfyiamcool/[email protected]/scheduler.go:395 +0x420

Goroutine 101 (running) created at:
  github.com/rfyiamcool/cronlib.(*JobModel).run()
      /home/espush/golang/pkg/mod/github.com/rfyiamcool/[email protected]/scheduler.go:411 +0x7ce

Goroutine 91 (running) created at:
  github.com/rfyiamcool/cronlib.(*JobModel).runLoop()
      /home/espush/golang/pkg/mod/github.com/rfyiamcool/[email protected]/scheduler.go:332 +0x56
==================

留意到代码里 UnRegister 是有使用 lock && unlock 的，所以外面是直接使用的，使用race 编译时提示 DATA race，两个goroutine 可能同时读写了 running 变量，是否是正常现象，这里用 atomic 来解决？

timer stop

https://github.com/rfyiamcool/cronlib/blob/master/scheduler.go#L339

timer没有进行stop操作，这个出于什么考虑？

Add an open source license

Is the project open source? Can you add an open source license file?

dynamic add job but not run

My sample code:

func RegisterCrontabController(c *gin.Context) {
var inputs APIRegisterCrontab
if err := c.Bind(&inputs); err != nil {
h.RespondHandler(400, err.Error(), c, "")
return
}

spec := inputs.SchedueTime
log.Println(spec, inputs.Guid)
// */2 * * * * *  biq5i2ickkuogr133b6g-1555323146
cron := g.CrontabSet.Get()
f := func() {
	log.Println("新增的任务,等待管理员分配机器~")
}
job, err := cronlib.NewJobModel(spec, f)
if err != nil {
	msg := fmt.Sprintf("init new job model failed: %s", err.Error())
	log.Printf(msg)
	h.RespondHandler(400, msg, c, "")
	return
}
err = cron.Register(inputs.Guid, job)
if err != nil {
	msg := fmt.Sprintf("register failed: %s", err.Error())
	log.Println(msg)
	h.RespondHandler(400, msg, c, "")
	return
}
msg := fmt.Sprintf("agent execute register job success")
log.Println(msg)
h.RespondHandler(200, msg, c, "")
return

}