Golang http代理

话不多说 直接上代码

package main

  import (
"fmt"
"io"
"net"
"net/http"
"strings"
  )

  type Pxy struct{}

  func (p *Pxy) ServeHTTP(rw http.ResponseWriter, req *http.Request) {
fmt.Printf("Received request %s %s %s\n", req.Method, req.Host, req.RemoteAddr)
fmt.Println(req.RequestURI)
transport := http.DefaultTransport
// step 1，浅拷贝对象，然后就再新增属性数据
outReq := new(http.Request)
*outReq = *req
if clientIP, _, err := net.SplitHostPort(req.RemoteAddr); err == nil {
if prior, ok := outReq.Header["X-Forwarded-For"]; ok {
clientIP = strings.Join(prior, ", ") + ", " + clientIP
}
outReq.Header.Set("X-Forwarded-For", clientIP)
}

// step 2, 请求下游
res, err := transport.RoundTrip(outReq)
if err != nil {
rw.WriteHeader(http.StatusBadGateway)
return
}

// step 3, 把下游请求内容返回给上游
for key, value := range res.Header {
for _, v := range value {
rw.Header().Add(key, v)
}
}
rw.Header().Set("aaaaaaaaaa","aaaaaaa")
rw.WriteHeader(res.StatusCode)
io.Copy(rw, res.Body)
res.Body.Close()
  }

  func main() {
fmt.Println("Serve on :8080")
http.Handle("/", &Pxy{})
http.ListenAndServe("0.0.0.0:8080", nil)
  }