1 内部服务器代码

package main
import (
    "fmt"
    "io"
    "log"
    "net/http"
    "os"
    "os/signal"
    "syscall"
    "time"
)
type RealServer struct {
    Addr string
}
func (this *RealServer) Run() {
    log.Println("真实服务器启动:" + this.Addr)
    mux := http.NewServeMux()
    mux.HandleFunc("/", this.Hello)
    server := &http.Server{
        Addr: this.Addr,
        WriteTimeout: time.Second * 3,
        Handler: mux,
    }
    go func() {
        log.Fatal(server.ListenAndServe())
    }()
}
func (this *RealServer) Hello(w http.ResponseWriter, r *http.Request) {
    // 127.0.0.1:8008/abc?sd=1
    // this.Addr = 127.0.0.1:8008
    // r.URL.Path = /abc
    urlPath := fmt.Sprintf("http://%s%s\n", this.Addr, r.URL.Path)
    _, _ = io.WriteString(w, urlPath)
}
func main() {
    rs1 := &RealServer{Addr: "127.0.0.1:2003"}
    rs1.Run()
    rs2 := &RealServer{Addr: "127.0.0.1:2004"}
    rs2.Run()
    quit := make(chan os.Signal)
    signal.Notify(quit, syscall.SIGINT, syscall.SIGTERM)
    <-quit
}

2 反向代理服务器代码

package main
import (
    "bufio"
    "log"
    "net/http"
    "net/url"
)
var (
    proxy_addr = "http://127.0.0.1:2003"  // 内部服务器IP和地址
    port = "2002"  // nginx反向代理服务器的端口为2002,  作为服务器2003的代理
)
func handler(w http.ResponseWriter, r *http.Request) {
    // 解析代理地址, 更改请求体的协议和主机
    proxy, err := url.Parse(proxy_addr)
    r.URL.Scheme = proxy.Scheme
    r.URL.Host = proxy.Host
    // 请求下游
    transport := http.DefaultTransport
    resp, err := transport.RoundTrip(r)
    if err != nil {
        log.Print(err)
        return
    }
    for k, vv := range resp.Header {
        for _, v := range vv {
            w.Header().Add(k, v)
        }
    }
    defer resp.Body.Close()
    _, _ = bufio.NewReader(resp.Body).WriteTo(w)
}
func main() {
    http.HandleFunc("/", handler)
    log.Println("start serving on port "+ port)
    err := http.ListenAndServe(":"+port, nil)
    if err != nil {
        log.Fatal(err)
    }
}