用Golang搭建简易代理服务器教程

package main

import (
    "log"
    "net/http"
    "net/http/httputil"
    "net/url"
)

type Proxy struct {
    target *url.URL
    proxy  *httputil.ReverseProxy
}

func NewProxy(targetHost string) (*Proxy, error) {
    targetURL, err := url.Parse(targetHost)
    if err != nil {
        return nil, err
    }

    proxy := httputil.NewSingleHostReverseProxy(targetURL)

    return &Proxy{target: targetURL, proxy: proxy}, nil
}

func (p *Proxy) ServeHTTP(w http.ResponseWriter, r *http.Request) {
    // 修改请求头，设置正确的转发信息
    r.Host = p.target.Host
    r.URL.Host = p.target.Host
    r.URL.Scheme = p.target.Scheme

    // 可选：添加自定义头信息
    r.Header.Set("X-Forwarded-Host", r.Header.Get("Host"))
    r.Header.Set("X-Origin-Host", p.target.Host)

    // 转发请求
    p.proxy.ServeHTTP(w, r)
}

func main() {
    // 设置你要代理的目标地址，例如：https://httpbin.org
    proxy, err := NewProxy("https://httpbin.org")
    if err != nil {
        log.Fatal("代理初始化失败：", err)
    }

    // 设置路由
    http.Handle("/", proxy)

    log.Println("代理服务器启动，监听 :8080")
    log.Fatal(http.ListenAndServe(":8080", nil))
}

go run proxy.go