./configure --with-http_secure_link_module #编译nginx时加入

nginx -V

server {
   listen    80;
   server_name download.52itstyle.com;
   charset utf-8;
   location / {
     #这里配置了2个参数一个是md5，一个是expires
     secure_link $arg_md5,$arg_expires;
     #md5的哈希格式为 secret+url+expires,expires为时间戳单位s，url为请求地址
     secure_link_md5 52itstyle$uri$arg_e;
     #这里我们的md5是我们按照secure_link_md5的方式计算的哈希，secure_link会比对它计算的哈希值是否与我们的md5参数一致
     if ($secure_link = "") {
       #资源不存在或哈希比对失败
       return 402;
     }
     if ($secure_link = "0") {
       #失效超时
       return 405;
     }
     #重命名文件名
     add_header Content-Disposition "attachment;filename=$arg_f";
     alias /data/site/down.52itstyle.com/;
   }
   error_page  500 502 503 504 /50x.html;
   error_page  402 405 /40x.html;
   location = /50x.html {
     root  html;
   }
   location = /40x.html {
     root  html;
   }
}

import org.apache.commons.codec.binary.Base64;
import org.apache.commons.codec.digest.DigestUtils;
/**
 * 生成加密連接
 */
public class SecureLink {
  private static String site = "https://down.52itstyle.com/";
  private static String secret = "52itstyle";
  public static String createLink(String path,String fileName){
    String time = String.valueOf((System.currentTimeMillis() / 1000) + 300); // 5分钟有效
    String md5 = Base64.encodeBase64URLSafeString(DigestUtils.md5(secret + path + time));
    String url = site + path + "" + md5 + "&expires=" + time + "&f="+fileName;
    return url;
  }
  public static void main(String[] args) {
    //https://down.52itstyle.com/2018101025689452.pdf"2018101025689452.pdf","分布式秒杀架构.pdf"));
  }
}