cron 中开启协程执行任务

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package cron

import (
	"project/internal/jobs"

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

func Run() {
	c := cron.New(cron.WithSeconds())

    // 每分钟的第 40 秒执行
	c.AddJob("40, * * * * *", jobs.OneMinuteJob{})

	// 启动一个 goroutine 去执行的
	c.Start()

	// 阻止主线程停止
	select {}
}

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package jobs

import (
	"fmt"
	"sync"
	"time"
)

var fullTimeFormat = "2006-01-02 15:04:05"

type OneMinuteJob struct {
}

var wg sync.WaitGroup

func (om OneMinuteJob) Run() {
    // 缓冲通道
	ch := make(chan int, 3)
	for i := 0; i < 10; i++ {
		ch <- i
		wg.Add(1)
		go test(ch)
	}

	close(ch)
	wg.Wait()
}

func test(ch chan int) {
	defer wg.Done()

	time.Sleep(time.Second * 3)
	i := <-ch
	fmt.Println("i =", i, time.Now().Format(fullTimeFormat))
}

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zhpj@localhost project % go run main.go cron
i = 0 2024-03-27 20:31:43
i = 1 2024-03-27 20:31:43
i = 2 2024-03-27 20:31:43

i = 3 2024-03-27 20:31:46
i = 4 2024-03-27 20:31:46
i = 5 2024-03-27 20:31:46

i = 6 2024-03-27 20:31:49
i = 7 2024-03-27 20:31:49
i = 8 2024-03-27 20:31:49

i = 9 2024-03-27 20:31:52



i = 0 2024-03-27 20:32:43
i = 1 2024-03-27 20:32:43
i = 2 2024-03-27 20:32:43

i = 3 2024-03-27 20:32:46
i = 4 2024-03-27 20:32:46
i = 5 2024-03-27 20:32:46

i = 6 2024-03-27 20:32:49
i = 7 2024-03-27 20:32:49
i = 8 2024-03-27 20:32:49

i = 9 2024-03-27 20:32:52

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参考文章：

Go 并发编程（一）：协程 goroutine、channel、协程池

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