go使用第三方库解析cron表达式

曾经终败给现在 2022-09-16 08:50 217阅读 0赞

## 第三方库 ##

[cronexpr的github地址][cronexpr_github]

## 代码演示 ##

package main
    
    import (
    	"fmt"
    	"github.com/gorhill/cronexpr"
    	"time"
    )
    
    /**
     * @author micro.cloud.fly
     * @date 2021/10/15 5:57 下午
     * @desc 演示调度协程
     */
    
    type Job struct {
        
    	conExpre *cronexpr.Expression
    	nextTime time.Time
    }
    
    func main() {
        
    
    	//定义两个Job
    	con1 := cronexpr.MustParse("*/3 * * * * * *")
    	now := time.Now()
    	job1 := Job{
        
    		conExpre: con1,
    		nextTime: con1.Next(now),
    	}
    	con2 := cronexpr.MustParse("*/5 * * * * * *")
    
    	job2 := Job{
        
    		conExpre: con2,
    		nextTime: con1.Next(now),
    	}
    
    	//定义一个map，用来存储这两个job
    	m := make(map[string]*Job)
    	m["job1"] = &job1
    	m["job2"] = &job2
    
    	//拉起一个协程，监控这两个任务
    	go func() {
        
    		for {
        
    
    			curr := time.Now()
    			for jobName, job := range m {
        
    				if job.nextTime.Before(curr) || job.nextTime.Equal(curr) {
        
    					//注意这里需要将变量复制过去，传到这个方法中
    					go func(jobname string) {
        
    						fmt.Println(curr, " 执行任务:", jobname)
    					}(jobName)
    					//重置下次执行时间
    					job.nextTime = job.conExpre.Next(curr)
    					fmt.Println(jobName, "下次执行时间为：", job.nextTime)
    				}
    			}
    			time.Sleep(100 * time.Millisecond)
    		}
    
    	}()
    
    	time.Sleep(20 * time.Second)
    }

执行输出

job1 下次执行时间为： 2021-10-15 18:07:51 +0800 CST
    job2 下次执行时间为： 2021-10-15 18:07:50 +0800 CST
    2021-10-15 18:07:48.015409 +0800 CST m=+1.232900015  执行任务: job1
    2021-10-15 18:07:48.015409 +0800 CST m=+1.232900015  执行任务: job2
    job2 下次执行时间为： 2021-10-15 18:07:55 +0800 CST
    2021-10-15 18:07:50.061674 +0800 CST m=+3.279103272  执行任务: job2
    job1 下次执行时间为： 2021-10-15 18:07:54 +0800 CST
    2021-10-15 18:07:51.09857 +0800 CST m=+4.315968560  执行任务: job1
    job1 下次执行时间为： 2021-10-15 18:07:57 +0800 CST
    2021-10-15 18:07:54.08335 +0800 CST m=+7.300659041  执行任务: job1
    job2 下次执行时间为： 2021-10-15 18:08:00 +0800 CST
    2021-10-15 18:07:55.009302 +0800 CST m=+8.226583525  执行任务: job2
    job1 下次执行时间为： 2021-10-15 18:08:00 +0800 CST
    2021-10-15 18:07:57.049528 +0800 CST m=+10.266748115  执行任务: job1
    job1 下次执行时间为： 2021-10-15 18:08:03 +0800 CST
    job2 下次执行时间为： 2021-10-15 18:08:05 +0800 CST
    2021-10-15 18:08:00.01745 +0800 CST m=+13.234580215  执行任务: job1
    2021-10-15 18:08:00.01745 +0800 CST m=+13.234580215  执行任务: job2
    job1 下次执行时间为： 2021-10-15 18:08:06 +0800 CST
    2021-10-15 18:08:03.075889 +0800 CST m=+16.292927628  执行任务: job1
    job2 下次执行时间为： 2021-10-15 18:08:10 +0800 CST
    2021-10-15 18:08:05.017993 +0800 CST m=+18.234974031  执行任务: job2
    job1 下次执行时间为： 2021-10-15 18:08:09 +0800 CST
    2021-10-15 18:08:06.038355 +0800 CST m=+19.255304875  执行任务: job1

[cronexpr_github]: http://github.com/gorhill/cronexpr