Go语言例子：带有超时的Http请求

代码如下，实现功能：80毫秒候HTTP请求 超时，自动取消。

package main

import "net/http"
import "log"
import "io/ioutil"
import "context"
import "time"

func main () {
  req, err := http.NewRequest(http.MethodGet, "http://httpbin.org/get", nil)
  if err != nil {
    log.Fatal(err)
  }
  ctx, cancel := context.WithTimeout(context.Background(), time.Duration(time.Millisecond*80))
  defer cancel()
  req = req.WithContext(ctx)
  c := &http.Client{}
  res, err := c.Do(req)
  if err != nil {
    log.Fatal(err)
  }
  defer res.Body.Close()
  out, err := ioutil.ReadAll(res.Body)
  if err != nil {
    log.Fatal(err)
  }
  log.Println(string(out))
}

This will automatically timeout and cancel the request after 80 milliseconds