七牛时间戳防盗链go语言实现

package main

import (
    "crypto/md5"
    "flag"
    "fmt"
    "net/url"
    "strings"
)

func main() {
    var t int64
    var key string
    var resUrl string

    flag.Int64Var(&t, "t", 0, "expire timestamp")
    flag.StringVar(&key, "key", "", "encrypt key")
    flag.StringVar(&resUrl, "url", "", "resource url")
    flag.Parse()

    if t == 0 || key == "" || resUrl == "" {
        return
    }

    expireTime := fmt.Sprintf("%x", t)

    resUri, pErr := url.Parse(resUrl)
    if pErr != nil {
        return
    }

    path := resUri.Path

    rawStr := fmt.Sprintf("%s%s%s", key, path, expireTime)

    md5H := md5.New()
    md5H.Write([]byte(rawStr))

    sign := fmt.Sprintf("%x", md5H.Sum(nil))

    var newUrl string
    if strings.Contains(resUrl, "?") {
        newUrl = fmt.Sprintf("%s&sign=%s&t=%s", resUrl, sign, expireTime)
    } else {
        newUrl = fmt.Sprintf("%s?sign=%s&t=%s", resUrl, sign, expireTime)
    }

    fmt.Println(newUrl)
}