package main

import (
    "context"
    "crypto/md5"
    "fmt"
    "log"
    "net/http"
    "os"
    "os/signal"
    "strings"
    "syscall"
)

func main() {
    mux := http.NewServeMux()
    mux.Handle("/access_log/post", &logHandler{})

    server := &http.Server{
        Addr:    ":5000",
        Handler: mux,
    }

    // 创建系统信号接收器
    done := make(chan os.Signal)
    signal.Notify(done, os.Interrupt, syscall.SIGINT, syscall.SIGTERM)
    go func() {
        <-done

        if err := server.Shutdown(context.Background()); err != nil {
            log.Fatal("Shutdown server:", err)
        }
    }()

    err := server.ListenAndServe()
    if err != nil {
        if err == http.ErrServerClosed {
            log.Print("Server closed under request")
        } else {
            log.Fatal("Server closed unexpected")
        }
    }
}

type logHandler struct{}

func (*logHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
    if r.Method == "POST" {
        query := r.URL.Query()
        authKey := query.Get("auth_key")
        accessKey := query.Get("access_key")//access_key 即您提供的SecretId
        authKeys := strings.Split(authKey, "-")
        if len(authKeys) == 3 {
            currentTimeTs := authKeys[0]
            
            //进行时间戳有效期判断
            RandNum := authKeys[1]
            md5Hash := authKeys[2]
            secretKey := getSecretKey(accessKey)
            authStr := fmt.Sprintf("%s-%s-%s-%s", "/access_log/post", currentTimeTs, RandNum, secretKey)
            data := []byte(authStr)
            has := md5.Sum(data)
            authMd5 := fmt.Sprintf("%x", has) //转换成字符串进行比较
            if authMd5 == md5Hash {
                // todo 认证成功
                if r.Header.Get("Content-Encoding") == "gzip" {
                    //解压数据
                }
                //数据处理
            }
        } else {
            //异常处理
        }
    }
}

// 获取SecretKey
func getSecretKey(accessKey string) string {
    if accessKey != "" {
        // 通过Access_key(SecretI)获取Secret_Key
        return "secret_key"
    }
    return ""
}