golang 速度限制，time.Tick(time.Second*2) channel，隔2秒后繼續執行

package main

import (
    "fmt"
    "time"
)

func main() {
    requests := make(chan int, 5)
    for i := 1; i <= 2; i++ {
        requests <- i
    }
    close(requests)
    limiter := time.Tick(time.Millisecond * 200)

    for req := range requests { //會循環兩次，前面往requests channel中發送了兩個值
        <-limiter  //執行到這里，需要隔 200毫秒才繼續往下執行，time.Tick(timer)上面已定義
        fmt.Println("request", req, time.Now())
    }

    burstyLimiter := make(chan time.Time, 3)

    for i := 0; i < 3; i++ {
        burstyLimiter <- time.Now()  //這里burstyLimiter channel 連續發送了三次值
    }

    go func() {
        for t := range time.Tick(time.Second * 2) {
            burstyLimiter <- t // 這里往burstyLimiter channel 循環發送time.Tick
        }
    }()
    burstyRequests := make(chan int, 5)

    for i := 1; i <= 5; i++ {
        burstyRequests <- i
        <-burstyLimiter  //前三次沒有速度限制，會直接打印出后面的println的內容
        fmt.Println("request", i, time.Now())
    }

    close(burstyRequests)
    for req := range burstyRequests {
        <-burstyLimiter  //繼續接收burstyLimiter值，除了前三次，后面的都是time.Tick進行速度限制,2秒打印一次，直到此次循環結束
        fmt.Println("request", req, time.Now())
    }
}

注，把time.Tick(time.Second)中的值改為秒會更容易查看效果