Spring MVC服务器端防止重复提交

时间：2016-10-14 18:19:57 阅读：484 评论：0 收藏：0 [点我收藏+]

标签：druid springmvc mybatis maven bootstrap

实现机制是使用token,简单说下:

(a)进入下单页,会生成一个token,同时存在两个地方:session(或redis也可以)和页面

(b)提交时,服务器接收到页面的token后,会和session中的token比较,相同则允许提交,同时删除session中的token;

(c)如果重复提交,则session中已经没有token(已被步骤b删除),那么校验不通过,则不会真正提交.

拦截器代码:下载

Java代码

package com.chanjet.gov.filter;
import org.apache.log4j.Logger;
import org.springframework.web.method.HandlerMethod;
import org.springframework.web.servlet.handler.HandlerInterceptorAdapter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.lang.reflect.Method;
import java.util.UUID;
/**
* Created by 黄威 on 9/20/16.<br >
* 防止下单页重复提交
*/
public class RepeatTokenInterceptor extends HandlerInterceptorAdapter {
private static Logger log = Logger.getLogger(RepeatTokenInterceptor.class);
@Override
public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
if (handler instanceof HandlerMethod) {
HandlerMethod handlerMethod = (HandlerMethod) handler;
Method method = handlerMethod.getMethod();
RepeatSubmitToken annotation = method.getAnnotation(RepeatSubmitToken.class);
if (annotation != null) {
boolean needSaveSession = annotation.save();
if (needSaveSession) {
request.getSession(true).setAttribute("repeattoken", UUID.randomUUID().toString());
}
boolean needRemoveSession = annotation.remove();
if (needRemoveSession) {
if (isRepeatSubmit(request)) {
log.warn("please don‘t repeat submit,url:" + request.getServletPath());
response.sendRedirect("/warn.html?code=repeatSubmitOrder&orgId="+request.getParameter("orgId"));
return false;
}
request.getSession(true).removeAttribute("repeattoken");
}
}
return true;
} else {
return super.preHandle(request, response, handler);
}
}
private boolean isRepeatSubmit(HttpServletRequest request) {
String serverToken = (String) request.getSession(true).getAttribute("repeattoken");
if (serverToken == null) {
return true;
}
String clinetToken = request.getParameter("repeattoken");
if (clinetToken == null) {
return true;
}
if (!serverToken.equals(clinetToken)) {
return true;
}
return false;
}
}

但是--

如果打开两个标签页,则这两个页面分别有一个token,并且是不同的(理论上是不同的),但是session中只有一份,

其中一个提交后,就会删除session中的token,那么另外一个页面提交时session中的token已为空,那么一定校验不通过.

根本原因:

在同一时刻,session中只存了一份token,而页面上可能有多个token(有n个页签,就会有n个不同的token).

既然找到了根本原因,那么也就自然而然产生了解决方案.

思路:session中不能只存储一份token,而是支持存储多个token

具体技术方案:下载

(1)每次进入下单页都会产生一个新的token,这个token都进入两个数据流:

--(a)传到页面,key是repeattoken

前端页面引用方式:

Html代码下载

<input type="hidden" name="repeattoken" value="${Session.repeattoken!}" >

--(b)存储到session(现在是增量,不会把原来的token替换掉)

(2)存储到session中的key应该与页面的key区分开来,使用"tokenpool"

优化之后的过滤器:下载

Java代码

package com.chanjet.gov.filter;
import com.chanjet.gov.util.StringUtil;
import org.apache.log4j.Logger;
import org.springframework.web.method.HandlerMethod;
import org.springframework.web.servlet.handler.HandlerInterceptorAdapter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.lang.reflect.Method;
import java.util.UUID;
/**
* Created by 黄威 on 9/20/16.<br >
* 防止下单页重复提交
*/
public class RepeatTokenInterceptor extends HandlerInterceptorAdapter {
/***
* 用于前端页面接收服务器端的token
*/
public static final String SESSION_KEY_REPEATTOKEN="repeattoken";
/***
* 用于session存储n个token
*/
public static final String SESSION_KEY_REPEATTOKEN_POOL = "tokenpool";
private static Logger log = Logger.getLogger(RepeatTokenInterceptor.class);
private void addRepeatToken(HttpServletRequest request, HttpServletResponse response){
HttpSession httpSession = request.getSession(true);
String token = (String) httpSession.getAttribute(SESSION_KEY_REPEATTOKEN_POOL);
System.out.println("addRepeatToken token:"+token);
String createdToken = UUID.randomUUID().toString();
httpSession.setAttribute(SESSION_KEY_REPEATTOKEN, createdToken);//给前端页面用的
if(StringUtil.isNullOrEmpty(token)){
httpSession.setAttribute(SESSION_KEY_REPEATTOKEN_POOL, createdToken);
}else{
httpSession.setAttribute(SESSION_KEY_REPEATTOKEN_POOL, createdToken + "###" + token);
}
}
private void removeRepeatToken(HttpServletRequest request, HttpServletResponse response){
HttpSession httpSession = request.getSession(true);
String token = (String) httpSession.getAttribute(SESSION_KEY_REPEATTOKEN_POOL);
System.out.println("removeRepeatToken token:"+token);
if(!StringUtil.isNullOrEmpty(token)){
String clientToken = (String) request.getParameter(SESSION_KEY_REPEATTOKEN);
System.out.println("removeRepeatToken serverToken:"+clientToken);
if (clientToken == null) {
return;
}
token = token.replace(clientToken, "").replace("######", "###");
System.out.println("token:"+token);
httpSession.setAttribute(SESSION_KEY_REPEATTOKEN_POOL, token);
}
}
@Override
public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
if (handler instanceof HandlerMethod) {
HandlerMethod handlerMethod = (HandlerMethod) handler;
Method method = handlerMethod.getMethod();
RepeatSubmitToken annotation = method.getAnnotation(RepeatSubmitToken.class);
if (annotation != null) {
boolean needSaveSession = annotation.save();
if (needSaveSession) {
addRepeatToken(request,response);
}
boolean needRemoveSession = annotation.remove();
if (needRemoveSession) {
if (isRepeatSubmit(request)) {
log.warn("please don‘t repeat submit,url:" + request.getServletPath());
response.sendRedirect("/warn.html?code=repeatSubmitOrder&orgId="+request.getParameter("orgId"));
return false;
}
removeRepeatToken(request,response);
}
}
return true;
} else {
return super.preHandle(request, response, handler);
}
}
private boolean isRepeatSubmit(HttpServletRequest request) {
//从池子里面获取token
String serverToken = (String) request.getSession(true).getAttribute(SESSION_KEY_REPEATTOKEN_POOL);
if (serverToken == null||"###".equals(serverToken)) {
return true;
}
String clinetToken = request.getParameter(SESSION_KEY_REPEATTOKEN);//请求要素
if (StringUtil.isNullOrEmpty(clinetToken)) {
return true;
}
System.out.println("clinetToken:"+clinetToken);
if (!serverToken.contains(clinetToken)) {
return true;
}
return false;
}
}

日志: