golang http连接复用方法

 package main import (	"fmt"	"io/ioutil"	"log"	"net/http"	"os"	"strconv"	"strings"	"time" ) func connHandler(w http.ResponseWriter, r *http.Request) {	// parse	r.ParseForm()	response_time := r.Header.Get("sleep-time")	// <= NOTE	if _, err := ioutil.ReadAll(r.Body); err != nil {	http.Error(w, err.Error(), 500)	return	}	defer r.Body.Close()	// sleep for some time	resp_time := 1	if response_time != "" {	ms, _ := strconv.ParseFloat(response_time, 64)	resp_time = (int)(ms * 1000)	}	time.Sleep(time.Duration(resp_time) * time.Millisecond)	// parepare response	status := 200	body := ""	w.Header().Set("Content-Type", "text/plain")	w.Header().Set("Content-Length", strconv.Itoa(len(body)))	w.WriteHeader(status)	w.Write([]byte(body)) } func main() {	http.HandleFunc("/", connHandler)	if err := http.ListenAndServe(":server_port", nil); err != nil {	log.Fatal("ListenAndServe: ", err)	} } 

 package main import ( "bytes" "fmt" "io" "io/ioutil" "log" "net/http" "time" ) var ( httpClient *http.Client ) const ( MaxIdleConnections int = 20 RequestTimeout int = 30 ) // init HTTPClient func init() { httpClient = createHTTPClient() } // createHTTPClient for connection re-use func createHTTPClient() *http.Client { client := &http.Client{ Transport: &http.Transport{ MaxIdle ConnsPerHost: MaxIdleConnections, }, Timeout: time.Duration(RequestTimeout) * time.Second, } return client } func conn_reuse_post(conn_reuse_times int) { var endPoint string = "http://server_ip:server_port/" data := []byte{} // fill data for i := 0; i < conn_reuse_times; i++ { // use global httpClient to send request resp, err := httpClient.Post(endPoint, "application/x-www-form-urlencoded", bytes.NewBuffer([]byte(data))) fmt.Println(resp) if err != nil { log.Println("err", err) return } io.Copy(ioutil.Discard, resp.Body) // <= NOTE resp.Body.Close() // <= NOTE } } func main() { conn_reuse_post(5) }