Golang如何实现HTTP请求转发_Golang代理请求与处理示例

package main

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

func main() {
    // 目标服务器地址
    target, _ := url.Parse("http://httpbin.org")

    // 创建反向代理
    proxy := httputil.NewSingleHostReverseProxy(target)

    // 设置处理函数
    http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
        // 可选：修改请求头
        r.Header.Set("X-Forwarded-Host", r.Host)
        r.Header.Set("X-Origin-Method", r.Method)

        // 执行转发
        proxy.ServeHTTP(w, r)
    })

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

director := func(req *http.Request) {
    target, _ := url.Parse("http://httpbin.org")
    
    // 更新请求的目标地址
    req.URL.Scheme = target.Scheme
    req.URL.Host = target.Host
    req.URL.Path = target.Path + req.URL.Path

    // 防止 Host 被保留为原始值
    if _, ok := req.Header["User-Agent"]; !ok {
        req.Header.Set("User-Agent", "my-proxy-agent")
    }
}

proxy := &httputil.ReverseProxy{Director: director}

transport := &http.Transport{}

proxy := &httputil.ReverseProxy{
    Director: func(req *http.Request) {
        target, _ := url.Parse("http://httpbin.org")
        req.URL.Scheme = target.Scheme
        req.URL.Host = target.Host
        req.URL.Path = target.Path + req.URL.Path
    },
    ModifyResponse: func(resp *http.Response) error {
        // 添加自定义响应头
        resp.Header.Set("X-Proxy-Status", "modified")
        
        // 示例：可在此读取 resp.Body 并替换
        return nil
    },
    Transport: transport,
}