init.go

package jobrunner

import (
	"fmt"
	"time"

	"github.com/robfig/cron/v3"
)

const DEFAULT_JOB_POOL_SIZE = 10

var (
	// Singleton instance of the underlying job scheduler.
	MainCron *cron.Cron

	// This limits the number of jobs allowed to run concurrently.
	workPermits chan struct{}

	// Is a single job allowed to run concurrently with itself?
	selfConcurrent bool

	IsStoreExecutionStatus  bool
	JobsExecutionStatusChan chan *JobStatus
)

var (
	green   = string([]byte{27, 91, 57, 55, 59, 52, 50, 109})
	magenta = string([]byte{27, 91, 57, 55, 59, 52, 53, 109})
	reset   = string([]byte{27, 91, 48, 109})

	functions = []interface{}{makeWorkPermits, isSelfConcurrent}
)

func makeWorkPermits(bufferCapacity int) {
	if bufferCapacity <= 0 {
		workPermits = make(chan struct{}, DEFAULT_JOB_POOL_SIZE)
	} else {
		workPermits = make(chan struct{}, bufferCapacity)
	}
}

func isSelfConcurrent(cocnurrencyFlag int) {
	if cocnurrencyFlag <= 0 {
		selfConcurrent = false
	} else {
		selfConcurrent = true
	}
}

func Start(loc *time.Location, isStoreExecutionStatus bool, v ...int) {
	if loc == nil {
		MainCron = cron.New(cron.WithParser(cron.NewParser(
			cron.SecondOptional | cron.Minute | cron.Hour | cron.Dom | cron.Month | cron.Dow | cron.Descriptor,
		)))
	} else {
		MainCron = cron.New(cron.WithLocation(loc), cron.WithParser(cron.NewParser(
			cron.SecondOptional|cron.Minute|cron.Hour|cron.Dom|cron.Month|cron.Dow|cron.Descriptor,
		)))
	}

	for i, option := range v {
		functions[i].(func(int))(option)
	}

	IsStoreExecutionStatus = isStoreExecutionStatus
	if IsStoreExecutionStatus {
		JobsExecutionStatusChan = make(chan *JobStatus)
	}

	MainCron.Start()

	fmt.Printf("%s[JobRunner] %v Started... %s \n",
		magenta, time.Now().Format("2006/01/02 - 15:04:05"), reset)

}