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
- 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
see more example
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)
}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)
...
}cron := cronlib.New()
...
cron.StopService(srvName)spec := "*/3 * * * * *"
srv := "risk.scan.total.5s.to.3s"
job, _ := cronlib.NewJobModel(
spec,
func() {
stdout(srv, spec)
},
)
err := cron.UpdateJobModel(srv, job)
...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)
}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
