本項目中只是簡單的實現頁面靜態化:將頁面直接緩存到用戶的瀏覽器上面
好處:用戶訪問數據的時候,不用去請求服務器,直接在本地緩存中取得需要的頁面緩存
未作頁面靜態化時的請求過程:請求某一個頁面,訪問緩存,查看緩存中是否有,緩存中有直接返回,緩存中沒有的話,將數據渲染到HTML頁面再存到緩存,再將整個HTML頁面返回給客戶端顯示
做了頁面靜態化的請求過程:第一次是去請求後臺渲染好的HTML頁面,之後的請求都是直接訪問用戶本地瀏覽器緩存的HTML頁面 和靜態資源,然後前端通過ajax來訪問後端,只去獲取頁面需要顯示的數據返回即可
對商品詳情頁面進行靜態化
在先前的操作中我們將商品詳情頁面進行了redis緩存,因爲這個接口只是展示相應產品詳情和秒殺倒計時等信息,只要顯示幾個關鍵信息即可,所以其他的都可以實行靜態化。這種技術,實際就是將前端分爲兩部分,一部分是不改變的HTML塊,還有一塊就是數據,它只要後端傳數據到前端即可,用到ajax技術來請求數據
- 爲了在瀏覽器端進行緩存,以及控制緩存時間,在application.properties裏面添加配置靜態資源配置項:
#static 靜態資源配置,設置靜態文件路徑css、js、圖片等
spring.resources.add-mappings=true
spring.resources.cache.period=3600
spring.resources.chain.cache=true
spring.resources.chain.enabled=true
spring.resources.chain.gzipped=true
spring.resources.chain.html-application-cache=true
spring.resources.static-locations=classpath:/static/
- 在static資源文件夾下面新建靜態資源頁面文件(以.htm格式結尾),這裏爲什麼不能用.html文件結尾是因爲如果不修改繼續用.html後綴,系統會默認去找templates下面的同名文件,所以修改它以示區別:
- 定義一個GoodsDetailVo類來專門給頁面傳值:
package com.javaxl.miaosha_05.vo;
import com.javaxl.miaosha_05.domain.MiaoshaUser;
public class GoodsDetailVo {
//秒殺狀態量初始值
private int miaoshaStatus = 0;
//開始時間倒計時
private int remainSeconds = 0;
private GoodsVo goods;
private MiaoshaUser user;
public int getMiaoshaStatus() {
return miaoshaStatus;
}
public void setMiaoshaStatus(int miaoshaStatus) {
this.miaoshaStatus = miaoshaStatus;
}
public int getRemainSeconds() {
return remainSeconds;
}
public void setRemainSeconds(int remainSeconds) {
this.remainSeconds = remainSeconds;
}
public GoodsVo getGoods() {
return goods;
}
public void setGoods(GoodsVo goods) {
this.goods = goods;
}
public MiaoshaUser getUser() {
return user;
}
public void setUser(MiaoshaUser user) {
this.user = user;
}
}
- 改造商品列表頁面(goods_list.html)裏面的跳轉邏輯,修改跳轉請求:
使用頁面靜態化後不需要再去服務端請求跳轉,可以直接去客戶端靜態資源裏面請求商品詳情靜態頁面goods_detail.htm,這裏注意修改一下後綴名稱
- 修改之前的商品詳情頁面,刪除thymeleaf具有的標籤,讓它成爲最初始的HTML靜態頁面(現在靜態頁面不需要thymeleaf),修改使其都使用id來標識各個組件:
- 一跳轉到goods_detail.htm頁面時,js初始化,調後端的接口請求數據渲染到頁面:
goods_detail.htm靜態頁面完整代碼:
<!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"
οnclick="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 getMiaoshaPath() {
var goodsId = $("#goodsId").val();
g_showLoading();
$.ajax({
url: "/miaosha/path",
type: "GET",
data: {
goodsId: goodsId,
verifyCode: $("#verifyCode").val()
},
success: function (data) {
if (data.code == 0) {
var path = data.data;
doMiaosha(path);
} else {
layer.msg(data.msg);
}
},
error: function () {
layer.msg("客戶端請求有誤");
}
});
}
function getMiaoshaResult(goodsId) {
g_showLoading();
$.ajax({
url: "/miaosha/result",
type: "GET",
data: {
goodsId: $("#goodsId").val(),
},
success: function (data) {
if (data.code == 0) {
var result = data.data;
if (result < 0) {
layer.msg("對不起,秒殺失敗");
} else if (result == 0) {//繼續輪詢
setTimeout(function () {
getMiaoshaResult(goodsId);
}, 200);
} else {
layer.confirm("恭喜你,秒殺成功!查看訂單?", {btn: ["確定", "取消"]},
function () {
window.location.href = "/order_detail.htm?orderId=" + result;
},
function () {
layer.closeAll();
});
}
} else {
layer.msg(data.msg);
}
},
error: function () {
layer.msg("客戶端請求有誤");
}
});
}
function doMiaosha(path) {
$.ajax({
url: "/miaosha/" + path + "/do_miaosha",
type: "POST",
data: {
goodsId: $("#goodsId").val()
},
success: function (data) {
if (data.code == 0) {
//window.location.href="/order_detail.htm?orderId="+data.data.id;
getMiaoshaResult($("#goodsId").val());
} else {
layer.msg(data.msg);
}
},
error: function () {
layer.msg("客戶端請求有誤");
}
});
}
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 () {
getDetail();
});
function getDetail() {
var goodsId = g_getQueryString("goodsId");//獲取請求路徑中的參數
$.ajax({
url: "/goods/detail/" + goodsId,
type: "GET",
success: function (data) {
if (data.code == 0) {
render(data.data);//使用render方法渲染頁面
} 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>
後端相關接口代碼:
/**
* 在html頁面上做ajax異步刷新,達到頁面僞靜態的效果
*/
@RequestMapping(value = "/detail/{goodsId}")
@ResponseBody
public Result<GoodsDetailVo> detail(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);
}