Job-processor which allows pending jobs to be superceded by newer jobs based on an arbitrary key associated with each job.
func main() {
js := jobmap.New()
ctx, cancelFunc := signal.NotifyContext(context.Background(), os.Interrupt)
defer cancelFunc()
go pumpJobs(js, cancelFunc)
js.Run(ctx)
}
func pumpJobs(js *jobmap.JobMap, cancelFunc context.CancelFunc) {
defer cancelFunc()
js.TakeJob("Apple", func(ctx context.Context) { fmt.Println("Apple has been bought."); time.Sleep(time.Second) })
js.TakeJob("Cheese", func(ctx context.Context) { fmt.Println("Cheese has been bought."); time.Sleep(time.Second) })
js.TakeJob("Apple", func(ctx context.Context) { fmt.Println("Apple has been peeled.") })
js.TakeJob("Cheese", func(ctx context.Context) { fmt.Println("Cheese has been cut.") })
js.TakeJob("Apple", func(ctx context.Context) { fmt.Println("Apple has been eaten.") })
js.TakeJob("Cheese", func(ctx context.Context) { fmt.Println("Cheese has been eaten.") })
time.Sleep(time.Second * 2)
}Output:
Apple has been bought.
Cheese has been bought.
Apple has been eaten.
Cheese has been eaten.
Two jobs with information about Apple and Cheese having been eaten do arrive before the first job for either finishes, so the two jobs containing information about their intermediate states (peeled and cut) are effectively skipped.