前言
我們本次要解決的問題有兩個大點
一、每次用戶請求都需要判斷其是否身份驗證過
解決方案:使用Aop來爲每一個需要進行身份驗證後才能調用的方法寫一個註解
思路:每次調用方法前都先判斷這個方法是否攜帶註解,如果沒攜帶則需要驗證。
二、頁面緩存,對象緩存,頁面僞靜態化(應對秒殺)
①頁面緩存:在一般的情況下,就比如說整個頁面的框架不變,就數據發生了改變的情況下,可以使用頁面緩存來加大反應速率。
②對象緩存:比如在每次用戶的請求下都需要判斷,所以我們直接通過根據在登錄時存在redis值的用戶進行判斷就行,
③頁面僞靜態化,因爲秒殺不同於普通的頁面(比如每個博客),它是需要進行數據的一個交互
一、Aop處理Token令牌
這個處理aop其實是涉及到很多的一個知識點,
所以用兩個案例來講吧:
先把代碼放着,注意此代碼僅僅只是一部分,並不全,想要源代碼的可以私聊
@Aspect
@Component
@Slf4j
public class MiaoshaUserTokenAspect {
@Autowired
MiaoshaUserService userService;
@Pointcut("execution( * com.javaxl.miaosha_05.controller.*.*(..))")
public void miaoshaUserTokenCut() {
}
@Around("miaoshaUserTokenCut()")
public Object doAround(ProceedingJoinPoint pjp) throws Throwable {
//獲取方法的參數
Object[] args = pjp.getArgs();
Signature s = pjp.getSignature();//獲取簽名
MethodSignature ms = (MethodSignature)s;//簽名轉方法簽名
Method m = ms.getMethod();//跟據簽名獲取方法
Annotation[] annotations = m.getAnnotations();//獲取註解
for (Annotation annotation : annotations) {
// 如果在方法上添加了DisableToken註解,那麼此方法是不需要token令牌就能訪問的
if(annotation instanceof DisableToken){
return pjp.proceed(args);//就直接運行
}
}
int count = 0;
HttpServletRequest request = null;
HttpServletResponse response = null;
MiaoshaUser miaoshaUser = null;
// 主要是對參數數組的中的秒殺User做封裝處理
int loop = 0;
for (int i = 0; i < args.length; i++) {//遍歷調用的這個方法的參數
if(args[i] instanceof HttpServletRequest){
count ++;
request = (HttpServletRequest)args[i];
}else if(args[i] instanceof HttpServletResponse){
count ++;
response = (HttpServletResponse)args[i];
}else if(args[i] instanceof MiaoshaUser){//找到其中的MiaoshaUser
count ++;
miaoshaUser = (MiaoshaUser)args[i];//放入到我們準備的容器
loop = i;
}
}
if(count == 3){//如果request,response,miaoshaUser,三個基本參數都有,則進行去Redis查找,前臺傳過來的token是否能在Redis中找到
String paramToken = request.getParameter(MiaoshaUserService.COOKI_NAME_TOKEN);
String cookieToken = getCookieValue(request, MiaoshaUserService.COOKI_NAME_TOKEN);
if(StringUtils.isEmpty(cookieToken) && StringUtils.isEmpty(paramToken)) {//如果兩個都爲空,就代表着前端的token既沒有傳參數過來,也沒有通過請求頭傳過來
throw new GlobalException(CodeMsg.SESSION_ERROR);
}
String token = StringUtils.isEmpty(paramToken)?cookieToken:paramToken;//如果參數不爲空就用參數傳過來的,反之使用請求頭裏的cookieToken
miaoshaUser = userService.getByToken(response, token);//這個方法是被封裝過的,就是從Redis獲取token相應的User對象
args[loop] = miaoshaUser;//給我們的參數裏的User賦值
}
Object ob = pjp.proceed(args);// ob 爲方法的返回值
return ob;
}
private String getCookieValue(HttpServletRequest request, String cookiName) {//判斷請求頭中是否有token的頭,如果有則獲取
Cookie[] cookies = request.getCookies();
if(cookies == null || cookies.length <= 0){//沒有cookies
return null;
}
for(Cookie cookie : cookies) {//有則獲取相應的值
if(cookie.getName().equals(cookiName)) {
return cookie.getValue();
}
}
return null;
}
}
1、如果不需要驗證身份信息
就比如我們的登錄:
在切面中的走向:
2、如果需要驗證身份信息
其他的業務方法:
接下來的走向:
二、頁面緩存,頁面僞靜態化(應對秒殺)
1、頁面緩存
其實按理來說大部分的博客,或者說一些相似的商品頁面都可以做到使用這種方式。
把整個頁面存放到redis中
OK,先放代碼
/**
* QPS:1267 load:15 mysql
* 5000 * 10
* QPS:2884, load:5
*
* 利用redis緩存整個商品列表
* */
@RequestMapping(value="/to_list", produces="text/html")
@ResponseBody
public String list(HttpServletRequest request, HttpServletResponse response, Model model, MiaoshaUser user) {
model.addAttribute("user", user);
//取緩存
String html = redisService.get(GoodsKey.getGoodsList, "", String.class);
if(!StringUtils.isEmpty(html)) {//如果自己渲染的html不爲空的話則直接返回
return html;
}
List<GoodsVo> goodsList = goodsService.listGoodsVo();
model.addAttribute("goodsList", goodsList);
// return "goods_list";
IWebContext ctx = new WebContext(request,response,
request.getServletContext(),request.getLocale(), model.asMap() );//把我們的基本商品信息放到web上下文裏
//手動渲染
html = thymeleafViewResolver.getTemplateEngine().process("goods_list", ctx);///跳轉到goods_list.html頁面
if(!StringUtils.isEmpty(html)) {
redisService.set(GoodsKey.getGoodsList, "", html);
}
return html;
}
講解:
或者說,這個展示詳情的也是一個意思:
/**
* 單個頁面詳情頁放到redis緩存中,1min後過期
* @param request
* @param response
* @param model
* @param user
* @param goodsId
* @return
*/
@RequestMapping(value="/to_detail2/{goodsId}",produces="text/html")
@ResponseBody
public String detail2(HttpServletRequest request, HttpServletResponse response, Model model,MiaoshaUser user,
@PathVariable("goodsId")long goodsId) {
model.addAttribute("user", user);
//取緩存
String html = redisService.get(GoodsKey.getGoodsDetail, ""+goodsId, String.class);
if(!StringUtils.isEmpty(html)) {
return html;
}
//手動渲染
GoodsVo goods = goodsService.getGoodsVoByGoodsId(goodsId);
model.addAttribute("goods", goods);
long startAt = goods.getStartDate().getTime();
long endAt = goods.getEndDate().getTime();
long now = System.currentTimeMillis();
int miaoshaStatus = 0;
int remainSeconds = 0;
if(now < startAt ) {//秒殺還沒開始,倒計時
miaoshaStatus = 0;
remainSeconds = (int)((startAt - now )/1000);
}else if(now > endAt){//秒殺已經結束
miaoshaStatus = 2;
remainSeconds = -1;
}else {//秒殺進行中
miaoshaStatus = 1;
remainSeconds = 0;
}
model.addAttribute("miaoshaStatus", miaoshaStatus);
model.addAttribute("remainSeconds", remainSeconds);
// return "goods_detail";
IWebContext ctx = new WebContext(request,response,
request.getServletContext(),request.getLocale(), model.asMap() );
html = thymeleafViewResolver.getTemplateEngine().process("goods_detail", ctx);
if(!StringUtils.isEmpty(html)) {
redisService.set(GoodsKey.getGoodsDetail, ""+goodsId, html);
}
return html;
}
2、頁面僞靜態化(應對秒殺)
goods_detail.htm代碼:
<!DOCTYPE HTML>
<html >
<head>
<title>商品詳情</title>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
<!-- jquery -->
<script type="text/javascript" src="/js/jquery.min.js"></script>
<!-- bootstrap -->
<link rel="stylesheet" type="text/css" href="/bootstrap/css/bootstrap.min.css" />
<script type="text/javascript" src="/bootstrap/js/bootstrap.min.js"></script>
<!-- jquery-validator -->
<script type="text/javascript" src="/jquery-validation/jquery.validate.min.js"></script>
<script type="text/javascript" src="/jquery-validation/localization/messages_zh.min.js"></script>
<!-- layer -->
<script type="text/javascript" src="/layer/layer.js"></script>
<!-- md5.js -->
<script type="text/javascript" src="/js/md5.min.js"></script>
<!-- common.js -->
<script type="text/javascript" src="/js/common.js"></script>
<style type="text/css">
html,body{
height:100%;
width:100%;
}
body{
background:url('/img/bg2.jpg') no-repeat;
background-size:100% 100%;
}
#goodslist td{
border-top:1px solid #39503f61;
}
</style>
</head>
<body>
<div class="panel panel-default" style="height:100%;background-color:rgba(222,222,222,0.8)" >
<div class="panel-heading">秒殺商品詳情</div>
<div class="panel-body">
<span id="userTip"> 您還沒有登錄,請登陸後再操作<br/></span>
<span>沒有收貨地址的提示。。。</span>
</div>
<table class="table" id="goodslist">
<tr>
<td>商品名稱</td>
<td colspan="3" id="goodsName"></td>
</tr>
<tr>
<td>商品圖片</td>
<td colspan="3"><img id="goodsImg" width="200" height="200" /></td>
</tr>
<tr>
<td>秒殺開始時間</td>
<td id="startTime"></td>
<td >
<input type="hidden" id="remainSeconds" />
<span id="miaoshaTip"></span>
</td>
<td>
<!--
<form id="miaoshaForm" method="post" action="/miaosha/do_miaosha">
<button class="btn btn-primary btn-block" type="submit" id="buyButton">立即秒殺</button>
<input type="hidden" name="goodsId" id="goodsId" />
</form>-->
<div class="row">
<div class="form-inline">
<img id="verifyCodeImg" width="80" height="32" style="display:none" onclick="refreshVerifyCode()"/>
<input id="verifyCode" class="form-control" style="display:none"/>
<button class="btn btn-primary" type="button" id="buyButton"οnclick="getMiaoshaPath()">立即秒殺</button>
</div>
</div>
<input type="hidden" name="goodsId" id="goodsId" />
</td>
</tr>
<tr>
<td>商品原價</td>
<td colspan="3" id="goodsPrice"></td>
</tr>
<tr>
<td>秒殺價</td>
<td colspan="3" id="miaoshaPrice"></td>
</tr>
<tr>
<td>庫存數量</td>
<td colspan="3" id="stockCount"></td>
</tr>
</table>
</div>
</body>
<script>
function render(detail){
var miaoshaStatus = detail.miaoshaStatus;
var remainSeconds = detail.remainSeconds;
var goods = detail.goods;
var user = detail.user;
if(user){
$("#userTip").hide();
}
$("#goodsName").text(goods.goodsName);
$("#goodsImg").attr("src", goods.goodsImg);
$("#startTime").text(new Date(goods.startDate).format("yyyy-MM-dd hh:mm:ss"));
$("#remainSeconds").val(remainSeconds);
$("#goodsId").val(goods.id);
$("#goodsPrice").text(goods.goodsPrice);
$("#miaoshaPrice").text(goods.miaoshaPrice);
$("#stockCount").text(goods.stockCount);
countDown();
}
$(function(){
//countDown();
getDetail();
});
function getDetail(){
var goodsId = g_getQueryString("goodsId");
$.ajax({
url:"/goods/detail/"+goodsId,
type:"GET",
success:function(data){
if(data.code == 0){
render(data.data);
}else{
layer.msg(data.msg);
}
},
error:function(){
layer.msg("客戶端請求有誤");
}
});
}
function countDown(){
var remainSeconds = $("#remainSeconds").val();
var timeout;
if(remainSeconds > 0){//秒殺還沒開始,倒計時
$("#buyButton").attr("disabled", true);
$("#miaoshaTip").html("秒殺倒計時:"+remainSeconds+"秒");
timeout = setTimeout(function(){
$("#countDown").text(remainSeconds - 1);
$("#remainSeconds").val(remainSeconds - 1);
countDown();
},1000);
}else if(remainSeconds == 0){//秒殺進行中
$("#buyButton").attr("disabled", false);
if(timeout){
clearTimeout(timeout);
}
$("#miaoshaTip").html("秒殺進行中");
$("#verifyCodeImg").attr("src", "/miaosha/verifyCode?goodsId="+$("#goodsId").val());
$("#verifyCodeImg").show();
$("#verifyCode").show();
}else{//秒殺已經結束
$("#buyButton").attr("disabled", true);
$("#miaoshaTip").html("秒殺已經結束");
$("#verifyCodeImg").hide();
$("#verifyCode").hide();
}
}
function refreshVerifyCode(){
$("#verifyCodeImg").attr("src", "/miaosha/verifyCode?goodsId="+$("#goodsId").val()+"×tamp="+new Date().getTime());
}
</script>
</html>
這樣可能就直接放兩個代碼,一個前端,一個後端,
1、在點擊時
2、點擊後跳轉到goods_detail.htm
3、調用的後臺代碼(基礎代碼,不過多講):
/**
* 在html頁面上做ajax異步刷新,達到頁面僞靜態的效果
* @param request
* @param response
* @param model
* @param user
* @param goodsId
* @return
*/
@RequestMapping(value="/detail/{goodsId}")
@ResponseBody
public Result<GoodsDetailVo> detail(HttpServletRequest request, HttpServletResponse response, Model model, MiaoshaUser user,
@PathVariable("goodsId")long goodsId) {
GoodsVo goods = goodsService.getGoodsVoByGoodsId(goodsId);
long startAt = goods.getStartDate().getTime();
long endAt = goods.getEndDate().getTime();
long now = System.currentTimeMillis();
int miaoshaStatus = 0;
int remainSeconds = 0;
if(now < startAt ) {//秒殺還沒開始,倒計時
miaoshaStatus = 0;
remainSeconds = (int)((startAt - now )/1000);
}else if(now > endAt){//秒殺已經結束
miaoshaStatus = 2;
remainSeconds = -1;
}else {//秒殺進行中
miaoshaStatus = 1;
remainSeconds = 0;
}
GoodsDetailVo vo = new GoodsDetailVo();
vo.setGoods(goods);
vo.setUser(user);
vo.setRemainSeconds(remainSeconds);
vo.setMiaoshaStatus(miaoshaStatus);
return Result.success(vo);
}
後言
看代碼慢慢琢磨,因爲這是簡單案例,不適合直接使用,僅僅只是給一個思路而已,
並且在前後端分離的項目中也可能有不同,
項目代碼:
鏈接:https://pan.baidu.com/s/1lLuT_BdfpdYxuKSGe_TQqw
提取碼:iqeb