Golang: Implementing a cron / executing tasks at a specific time
In case someone drops in on this question searching for a quick solution. I found a neat library that makes it really easy to schedule jobs.
Link: https://github.com/jasonlvhit/gocron
The API is pretty straightforward:
import (
"fmt"
"github.com/jasonlvhit/gocron"
)
func task() {
fmt.Println("Task is being performed.")
}
func main() {
s := gocron.NewScheduler()
s.Every(2).Hours().Do(task)
<- s.Start()
}
This is a general implementation, which lets you set:
- interval period
- hour to tick
- minute to tick
- second to tick
UPDATED: (the memory leak was fixed)
import (
"fmt"
"time"
)
const INTERVAL_PERIOD time.Duration = 24 * time.Hour
const HOUR_TO_TICK int = 23
const MINUTE_TO_TICK int = 00
const SECOND_TO_TICK int = 03
type jobTicker struct {
timer *time.Timer
}
func runningRoutine() {
jobTicker := &jobTicker{}
jobTicker.updateTimer()
for {
<-jobTicker.timer.C
fmt.Println(time.Now(), "- just ticked")
jobTicker.updateTimer()
}
}
func (t *jobTicker) updateTimer() {
nextTick := time.Date(time.Now().Year(), time.Now().Month(),
time.Now().Day(), HOUR_TO_TICK, MINUTE_TO_TICK, SECOND_TO_TICK, 0, time.Local)
if !nextTick.After(time.Now()) {
nextTick = nextTick.Add(INTERVAL_PERIOD)
}
fmt.Println(nextTick, "- next tick")
diff := nextTick.Sub(time.Now())
if t.timer == nil {
t.timer = time.NewTimer(diff)
} else {
t.timer.Reset(diff)
}
}