SecKillShop

主要实现一个商品秒杀的功能，梳理如何应对高并发的的技术的思路。

所用技术

1.后端：SpringBoot、JSR303、MyBatis

2.前端：Thymeleaf、BootStrap、Jquery

3.中间件：RabbitMQ、Redis、Druid

项目搭建

1.搭建SpringBoot

1.添加maven
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.5.9.RELEASE</version>
    </parent>
    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
    </dependencies>

2.集成thymeleaf

    1.导入依赖
        <dependency>
              <groupId>org.springframework.boot</groupId>
              <artifactId>spring-boot-starter-thymeleaf</artifactId>
        </dependency>

    2.添加配置项：
      spring.thymeleaf.cache=false
      spring.thymeleaf.content-type=text/html
      spring.thymeleaf.enabled=true
      spring.thymeleaf.encoding=UTF-8
      spring.thymeleaf.mode=HTML5
      spring.thymeleaf.prefix=classpath:/templates/
      spring.thymeleaf.suffix=.html

    3.添加thymeleaf模版
      <!DOCTYPE HTML>
      <html xmlns:th="http://www.thymeleaf.org">
      <head>
        <title>hello</title>
        <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
      </head>
      <body>
        <p th:text="'hello:'+${name}" ></p>
      </body>
      </html>

3.集成MyBatis

  1.添加依赖
    <dependency>
      <groupId>org.mybatis.spring.boot</groupId>
      <artifactId>mybatis-spring-boot-starter</artifactId>
      <version>1.3.1</version>
    </dependency>
  2.添加配置
    # mybatis
    mybatis.type-aliases-package=com.chengxiaoxiao.seckillshop.domain
    mybatis.configuration.map-underscore-to-camel-case=true
    mybatis.configuration.default-fetch-size=100
    mybatis.configuration.default-statement-timeout=3000
    mybatis.mapperLocations = classpath:com/chengxiaoxiao/seckillshop/dao/*.xml

4.添加MySql和Druid

    1.添加依赖
        <dependency>
          <groupId>mysql</groupId>
          <artifactId>mysql-connector-java</artifactId>
        </dependency>

        <dependency>
          <groupId>com.alibaba</groupId>
          <artifactId>druid</artifactId>
          <version>1.0.5</version>
        </dependency>
    2.添加配置
        spring.datasource.url=jdbc:mysql://localhost:3306/miaosha?useUnicode=true&characterEncoding=utf-8&allowMultiQueries=true&useSSL=false&serverTimezone=GMT%2B8
        spring.datasource.username=root
        spring.datasource.password=123456
        spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
        spring.datasource.type=com.alibaba.druid.pool.DruidDataSource
        spring.datasource.filters=stat
        spring.datasource.maxActive=2
        spring.datasource.initialSize=1
        spring.datasource.maxWait=60000
        spring.datasource.minIdle=1
        spring.datasource.timeBetweenEvictionRunsMillis=60000
        spring.datasource.minEvictableIdleTimeMillis=300000
        spring.datasource.validationQuery=select 'x'
        spring.datasource.testWhileIdle=true
        spring.datasource.testOnBorrow=false
        spring.datasource.testOnReturn=false
        spring.datasource.poolPreparedStatements=true
        spring.datasource.maxOpenPreparedStatements=20
        logging.leve.com.chengxiaoxiao.seckillshop=debug

5.安装redis

    1.官网：https://redis.io/download
   2.解压安装：
      1.解压文件：tar -zxvf redis-5.0.0.tar.gz
      2.移动到安装目录：mv redis-5.0.0 /usr/local/redis
      3.编译一下：make -j 4
        编译依赖gcc，安装如下：
          1.yum  install  gcc
          2.验证是否安装成功：rpm -qa |grep gcc
      4.make install
      5.修改配置文件
        vi redis.config
          1.修改可访问IP：修改bind 127.0.0.1  为bind 0.0.0.0
          2.修改后台启用：daemonize yes
          3.添加密码：requirepass
      6.运行：redis-server ./redis.conf
      7.重启：redis-cli     shutdown save
      8.命令行登录：auth password
      9.修改redis为系统服务
        1.cd utils
        2.  ./install_server.sh
        
        config:  /usr/local/redis/redis.config
        log:	/usr/local/redis/redis.log
        data:	/usr/local/redis/data
      10.查看后台进程是否存在
        1.查看进程：ps -ef |grep redis
        2.端口是否在监听：netstat -lntp | grep 6379
    3.添加依赖
          <dependency>
            <groupId>redis.clients</groupId>
            <artifactId>jedis</artifactId>
          </dependency>

          <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.2.38</version>
          </dependency>
    4.添加配置：
          #redis            
          redis.host=192.168.220.128
          redis.port=6379
          redis.timeout=3
          redis.password=123456
          redis.poolMaxTotal=10
          redis.poolMaxIdle=10
          redis.poolMaxWait=3

6.防火墙开启端口

获取zone名称：firewall-cmd --get-active-zones
执行防火墙开启端口：firewall-cmd --zone=public --add-port=6379/tcp --permanent
重启防火墙：firewall-cmd --reload
查看端口是否开启：firewall-cmd --query-port=6379/tcp
查看服务：chkconfig --list | grep redis

7.添加集成MD5加密

添加依赖：

<dependency>
    <groupId>commons-codec</groupId>
    <artifactId>commons-codec</artifactId>
</dependency>
<dependency>
    <groupId>org.apache.commons</groupId>
    <artifactId>commons-lang3</artifactId>
    <version>3.6</version>
</dependency>

2.调用方法：

DigestUtils.md5Hex(src);

8.添加JSR303校验

1.添加依赖

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-validation</artifactId>
</dependency>

2.Controller中Vo上添加注解@Valid

3.自定义注解

1.添加注解类实现方法，注解类模板：

@Target({ METHOD, FIELD, ANNOTATION_TYPE, CONSTRUCTOR, PARAMETER })
@Retention(RUNTIME)
@Documented
@Constraint(validatedBy = {IsMobileValidator.class })
public @interface IsMobile {

    String message() default "手机号码格式错误";

    Class<?>[] groups() default { };

    Class<? extends Payload>[] payload() default { };

}

2.添加注解校验规则类

public class IsMobileValidator implements ConstraintValidator<IsMobile, String> {
    @Override
    public void initialize(IsMobile constraintAnnotation) {
        
    }

    @Override
    public boolean isValid(String s, ConstraintValidatorContext constraintValidatorContext) {
        return true;
    }
}

2.使用

Vo对应属性上增加注解，实现校验

9.优化登录成功后，需要多次获取Cookie

1.自定义类，继承自WebMvcConfigurerAdapter，并添加@Configuration注解,使用参数解析器，重写addArgumentResolvers方法，添加自定义的解析器

2.自定义参数解析器，实现HandlerMethodArgumentResolver接口，重写supportsParameter和resolveArgument。

3.这样就可以直接在参数中增加对应的user，直接获取值了

Jemter压力测试

1.官网：http://jmeter.apache.org/

2.下载地址http://jmeter.apache.org/download_jmeter.cgi

3.修改界面为中文：

    找到jmeter下的bin目录，打开jmeter.properties 文件
    第三十七行修改为
    language=zh_CN

3.基本步骤：

    1.添加线程组
    2.添加HTTP请求配置器：

SpringBoot 打war包

1.添加依赖

    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-tomcat</artifactId>
        <scope>provided</scope>
    </dependency>

2.添加plugins

<build>
    <finalName>${project.artifactId}</finalName>
    <plugins>
        <plugin>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-maven-plugin</artifactId>
        </plugin>
    </plugins>
</build>

3.修改打包方式为war

<packaging>war</packaging>

4.mainApplication需要继承SpringBootServletInitializer,并重写configure方法

@Override
protected SpringApplicationBuilder configure(SpringApplicationBuilder builder) {
    return builder.sources(MainApplication.class);
}

5.项目根目录打包：mvn clean package 6.放tomcat目录下，启动（解决需要增加应用名） 1.可以把context设置为空 2.直接放到ROOT目录下

页面优化

一、页面缓存

把页面渲染好的页面缓存放入redis

实现代码：

1.SpringBoot 2.0写法

//取缓存
WebContext ctx = new WebContext(request, response, request.getServletContext(), request.getLocale(), model.asMap());
html = thymeleafViewResolver.getTemplateEngine().process("goodlist", ctx);
if (!StringUtils.isEmpty(html)) {
    redisService.set(GoodsKey.getGoodList, "", html);
}

2.SpringBoot 1.0写法

SpringWebContext context = new SpringWebContext(request,response,request.getServletContext(),request.getLocale(),model.asMap(),applicationContext);
String html = thymeleafViewResolver.getTemplateEngine().process("goods_list",context);

二、对象缓存

1.在Service中，取Dao的数据时，先取redis的数据，如果redis中没有才取数据库的数据。当数据库数据修改时，自动修改redis的数据

三、页面静态化

1.vue，angular进行页面静态化，减少服务器请求

热部署问题：

<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-devtools</artifactId>
        <optional>true</optional>
    </dependency>
</dependencies>

添加maven后，会自动添加热部署功能。但需要进行重新编译才可以实现更新

静态资源优化

1.JS/CSS压缩

2.多个CSS/JS合并，减少链接

集成RabbitMQ

1.安装erlong

1.安装依赖：

yum install ncurses-devel

2.下载erlang包，编译安装

1)http://www.erlang.org/downloads

2.安装RabbitMQ

1.下载地址：http://www.rabbitmq.com/install-generic-unix.html

错误记录

(1).报错

    An attempt was made to call the method javax.servlet.ServletContext.getVirtualServerName()Ljava/lang/String; but it does not exist. Its class, javax.servlet.ServletContext, is available from the following locations:

    jar:file:/Users/ac/.gradle/caches/modules-2/files-2.1/javax.servlet/servlet-api/2.4/3fc542fe8bb8164e8d3e840fe7403bc0518053c0/servlet-api-2.4.jar!/javax/servlet/ServletContext.class
    jar:file:/Users/ac/.gradle/caches/modules-2/files-2.1/org.apache.tomcat.embed/tomcat-embed-core/8.5.34/a038040d68a90397f95dd1e11b979fe364a5000f/tomcat-embed-core-8.5.34.jar!/javax/servlet/ServletContext.class

(2).解决：servlet-api版本太低，升级即可，
    1.下载tomcat.zip包（https://tomcat.apache.org/download-80.cgi），
    2.找到lib/servlet-api.jar，复制到java jdk目录下/jre/lib/ext下

iquanzhan/SecKillShop

SecKillShop

所用技术

项目搭建

1.搭建SpringBoot

2.集成thymeleaf

3.集成MyBatis

4.添加MySql和Druid

5.安装redis

6.防火墙开启端口

7.添加集成MD5加密

8.添加JSR303校验

1.添加依赖

2.Controller中Vo上添加注解@Valid

3.自定义注解

9.优化登录成功后，需要多次获取Cookie

Jemter压力测试

SpringBoot 打war包

页面优化

热部署问题：

静态资源优化

集成RabbitMQ

错误记录