swys/goscheduler

schedule tasks in go on an interval

goscheduler

go program that takes a "task" function and a time.Duration interval and will call the task continuously until the program exists or Done() method is called on the scheduler object.

example

package main

import (
  "fmt"
  "time"
  "github.com/swys/goscheduler"
)

func task() {
  fmt.Printf("I am a task\n")
}

func main() {
  // setup interval
  interval := time.Duration(1) * time.Second
  // get scheduler object and schedulerFunc (go routine used to run the task based on interval)
  scheduler := goscheduler.NewScheduler(interval, task)
  // start the interval to run the tasks
  go scheduler.schedulerFunc()
  // sleep for 2 secs to simulate a later time when you want to stop the scheduler
  time.Sleep(2 * time.Second)
  // stop the scheduler
  scheduler.Done()
}

functions

NewScheduler(interval time.Duration, task func()) (*Scheduler, func())

this creates a new scheduler object. The object contains a schedulerFunc method which is the func() you passed into NewScheduler. You must start the scheduler by running this schedulerFunc method as a go routine like below :

// create scheduler object
scheduler := NewScheduler(interval, task)
// start the scheduler
go scheduler.schedulerFunc()

arguments:

argument	type	example	description
interval	time.Duration	time.Duration(1)*time.Second	how often should your task run?
task	func()	func task() {...}	function to run

return:

return	type	description
scheduler	*Scheduler	scheduler object with Done() method for stopping scheduler

methods

schedulerFunc()

This method runs the function that was originally passed into NewScheduler to create the scheduler object. You must call this method to start the scheduler interval.

Done()

call this method on the Scheduler object when you want to stop the scheduler from running. This method is safe to call as many time as you want, weather the Scheduler go routine is running or not or even if the scheduler has not been initialized yet with an interval and a task function.

scheduler := NewScheduler(interval, task)
go scheduler.schedulerFunc()
// some time in the future when you want to stop the scheduler
scheduler.Done()
// from this point on, the task will not be called anymore

IsRunning() int64

call this method when you want to find out if the Scheduler's go routine is running or not. This will return an int64 and a value of 0 means the scheduler is NOT running. A value of 1 means the scheduler is running.

scheduler := NewScheduler(interval, task)
go scheduler.schedulerFunc()
// find out if scheduler is running
isRunning := scheduler.IsRunning() // returns 1

test

make test

license

MIT