router.POST("/api", func(c *gin.Context) {
proxy := httputil.ReverseProxy{Director: func(request *http.Request) {
request = c.Request
proxy.ServeHTTP(c.Writer, c.Request)
转发指定路径给后端服务
router.POST("/api/v1/backend", ReverseProxy())
func ReverseProxy() gin.HandlerFunc {
host := "backend_server_host"
return func(c *gin.Context) {
uri := "http://" + host
remote, err := url.Parse(uri) // backend server
if err != nil {
log.Fatal(err)
proxy := httputil.NewSingleHostReverseProxy(remote)
proxy.ServeHTTP(c.Writer, c.Request)
将所有路径都转发
router.Any("/*path", ReverseProxy)
func ReverseProxy(c *gin.Context) {
host := "backend_server_host"
proxy := &httputil.ReverseProxy{}
proxy.Director = func(req *http.Request) {
req.Header = c.Request.Header
req.Host = c.Request.Host // 使用客户端Host,避免301重定向问题
req.URL.Scheme = "http"
req.URL.Host = host
req.URL.Path = c.Param("path") // 请求路径地址,或者直接使用c.Request.URL.Path
proxy.ModifyResponse = func(resp *http.Response) error {
// NOTE 修改响应给客户端的response, 或者用于统计响应时间
return nil
proxy.ServeHTTP(c.Writer, c.Request)
官方代理示例
package main
import (
"bufio"
"log"
"net/http"
"net/url"
"github.com/gin-gonic/gin"
const (
// this is our reverse server ip address
ReverseServerAddr = "127.0.0.1:2002"
// maybe we can have many real server addresses and do some load balanced strategy.
var RealAddr = []string{
"http://127.0.0.1:2003",
// a fake function that we can do strategy here.
func getLoadBalanceAddr() string {
return RealAddr[0]
func main() {
r := gin.Default()
r.GET("/:path", func(c *gin.Context) {
// step 1: resolve proxy address, change scheme and host in requets
req := c.Request
proxy, err := url.Parse(getLoadBalanceAddr())
if err != nil {
log.Printf("error in parse addr: %v", err)
c.String(500, "error")
return
req.URL.Scheme = proxy.Scheme
req.URL.Host = proxy.Host
// step 2: use http.Transport to do request to real server.
transport := http.DefaultTransport
resp, err := transport.RoundTrip(req)
if err != nil {
log.Printf("error in roundtrip: %v", err)
c.String(500, "error")
return
// step 3: return real server response to upstream.
for k, vv := range resp.Header {
for _, v := range vv {
c.Header(k, v)
defer resp.Body.Close()
bufio.NewReader(resp.Body).WriteTo(c.Writer)
return
if err := r.Run(ReverseServerAddr); err != nil {
log.Printf("Error: %v", err)
reverse-proxy example
golang gin 代理和改包