高并发项目-分布式Session解决方案

分布式Session解决方案

1.保存Session，进入商品列表页面

1.保存Session

1.编写工具类

1.MD5Util.java

package com.sxs.seckill.utils;import org.apache.commons.codec.digest.DigestUtils;/*** Description: MD5加密工具类** @Author sun* @Create 2024/5/5 14:23* @Version 1.0*/
public class MD5Util {/*** 将一个字符串转换为MD5* @param src* @return*/public static String md5(String src) {return DigestUtils.md5Hex(src);}// 固定的saltpublic static final String SALT = "4tIY5VcX";// 第一次加密加盐public static String inputPassToMidPass(String inputPass) {// 加盐String str = SALT.charAt(0) + inputPass + SALT.charAt(6);return md5(str);}/*** 第二次加密加盐* @param midPass* @param salt* @return*/public static String midPassToDBPass(String midPass, String salt) {String str = salt.charAt(0) + midPass + salt.charAt(5);return md5(str);}/*** 两次加密* @param input* @param saltDB* @return*/public static String inputPassToDBPass(String input, String saltDB) {String midPass = inputPassToMidPass(input);String dbPass = midPassToDBPass(midPass, saltDB);return dbPass;}
}

2.CookieUtil.java

package com.sxs.seckill.utils;import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.UnsupportedEncodingException;
import java.net.URLDecoder;
import java.net.URLEncoder;/*** Description: Cookie工具类** @Author sun* @Create 2024/5/6 16:04* @Version 1.0*/public class CookieUtil {/*** 得到 Cookie 的值, 不编码** @param request* @param cookieName* @return*/public static String getCookieValue(HttpServletRequest request, StringcookieName) {return getCookieValue(request, cookieName, false);}/*** 得到 Cookie 的值, *** @param request* @param cookieName* @return*/public static String getCookieValue(HttpServletRequest request, StringcookieName, boolean isDecoder) {Cookie[] cookieList = request.getCookies();if (cookieList == null || cookieName == null) {return null;}String retValue = null;try {for (int i = 0; i < cookieList.length; i++) {if (cookieList[i].getName().equals(cookieName)) {if (isDecoder) {retValue = URLDecoder.decode(cookieList[i].getValue(), "UTF-8");} else {retValue = cookieList[i].getValue();}break;}}} catch (UnsupportedEncodingException e) {e.printStackTrace();}return retValue;}/*** 得到 Cookie 的值, *** @param request* @param cookieName* @param encodeString* @return*/public static String getCookieValue(HttpServletRequest request, StringcookieName, String encodeString) {Cookie[] cookieList = request.getCookies();if (cookieList == null || cookieName == null) {return null;}String retValue = null;try {for (int i = 0; i < cookieList.length; i++) {if (cookieList[i].getName().equals(cookieName)) {retValue = URLDecoder.decode(cookieList[i].getValue(), encodeString);break;}}} catch (UnsupportedEncodingException e) {e.printStackTrace();}return retValue;}/*** 设置 Cookie 的值 不设置生效时间默认浏览器关闭即失效,也不编码*/public static void setCookie(HttpServletRequest request, HttpServletResponseresponse, String cookieName, String cookieValue) {setCookie(request, response, cookieName, cookieValue, -1);}/*** 设置 Cookie 的值 在指定时间内生效,但不编码*/public static void setCookie(HttpServletRequest request, HttpServletResponseresponse, String cookieName, String cookieValue, int cookieMaxage) {setCookie(request, response, cookieName, cookieValue, cookieMaxage,false);}/*** 设置 Cookie 的值 不设置生效时间,但编码*/public static void setCookie(HttpServletRequest request, HttpServletResponseresponse, String cookieName, String cookieValue, boolean isEncode) {setCookie(request, response, cookieName, cookieValue, -1, isEncode);}/*** 设置 Cookie 的值 在指定时间内生效, 编码参数*/public static void setCookie(HttpServletRequest request, HttpServletResponseresponse, String cookieName, String cookieValue, int cookieMaxage, booleanisEncode) {doSetCookie(request, response, cookieName, cookieValue, cookieMaxage,isEncode);}/*** 设置 Cookie 的值 在指定时间内生效, 编码参数(指定编码)*/public static void setCookie(HttpServletRequest request, HttpServletResponseresponse, String cookieName, String cookieValue, int cookieMaxage, StringencodeString) {doSetCookie(request, response, cookieName, cookieValue, cookieMaxage, encodeString);}/*** 删除 Cookie 带 cookie 域名*/public static void deleteCookie(HttpServletRequest request, HttpServletResponse response, String cookieName) {doSetCookie(request, response, cookieName, "", -1, false);}/*** 设置 Cookie 的值，并使其在指定时间内生效** @param cookieMaxage cookie 生效的最大秒数*/private static final void doSetCookie(HttpServletRequest request, HttpServletResponse response, String cookieName, String cookieValue,int cookieMaxage, boolean isEncode) {try {if (cookieValue == null) {cookieValue = "";} else if (isEncode) {cookieValue = URLEncoder.encode(cookieValue, "utf-8");}Cookie cookie = new Cookie(cookieName, cookieValue);if (cookieMaxage > 0) {cookie.setMaxAge(cookieMaxage);}// if (null != request) {// 设置域名的 cookie// String domainName = getDomainName(request);// if (!"localhost".equals(domainName)) {// cookie.setDomain(domainName);// }// }cookie.setPath("/");response.addCookie(cookie);} catch (Exception e) {e.printStackTrace();}}/*** 设置 Cookie 的值，并使其在指定时间内生效** @param cookieMaxage cookie 生效的最大秒数*/private static final void doSetCookie(HttpServletRequest request,HttpServletResponse response, String cookieName, String cookieValue,int cookieMaxage, String encodeString) {try {if (cookieValue == null) {cookieValue = "";} else {cookieValue = URLEncoder.encode(cookieValue, encodeString);}Cookie cookie = new Cookie(cookieName, cookieValue);if (cookieMaxage > 0) {cookie.setMaxAge(cookieMaxage);}if (null != request) {// 设置域名的 cookieString domainName = getDomainName(request);System.out.println(domainName);if (!"localhost".equals(domainName)) {cookie.setDomain(domainName);}}cookie.setPath("/");response.addCookie(cookie);} catch (Exception e) {e.printStackTrace();}}/*** 得到 cookie 的域名*/private static final String getDomainName(HttpServletRequest request) {String domainName = null;// 通过 request 对象获取访问的 url 地址String serverName = request.getRequestURL().toString();if ("".equals(serverName)) {domainName = "";} else {// 将 url 地下转换为小写serverName = serverName.toLowerCase();// 如果 url 地址是以 http://开头 将 http://截取if (serverName.startsWith("http://")) {serverName = serverName.substring(7);}int end = serverName.length();// 判断 url 地址是否包含"/"if (serverName.contains("/")) {// 得到第一个"/"出现的位置end = serverName.indexOf("/");}// 截取serverName = serverName.substring(0, end);// 根据"."进行分割final String[] domains = serverName.split("\\.");int len = domains.length;if (len > 3) {// www.abc.com.cndomainName = domains[len - 3] + "." + domains[len - 2] + "." +domains[len - 1];} else if (len > 1) {// abc.com or abc.cndomainName = domains[len - 2] + "." + domains[len - 1];} else {domainName = serverName;}}if (domainName.indexOf(":") > 0) {String[] ary = domainName.split("\\:");domainName = ary[0];}return domainName;}
}

2.关于session和cookie关系的回顾

• 当浏览器请求到服务端时cookie会携带sessionid
• 然后在服务端getSession时会得到当前用户的session
• cookie-sessionid 连接到session

3.修改UserServiceImpl.java的doLogin方法，增加保存信息到session的逻辑

4.测试，用户票据成功保存到cookie中

2.访问到商品列表页面

1.编写GoodsController.java 验证用户登录后进入商品列表页

package com.sxs.seckill.controller;import com.sxs.seckill.pojo.User;
import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.CookieValue;
import org.springframework.web.bind.annotation.RequestMapping;import javax.servlet.http.HttpSession;/*** Description:** @Author sun* @Create 2024/5/6 18:16* @Version 1.0*/
@Controller
@Slf4j
@RequestMapping("/goods")
public class GoodsController {// 进入到商品首页@RequestMapping("/toList")public String toList(HttpSession session, Model model, @CookieValue("userTicket") String ticket) {// 首先判断是否有票据if (null == ticket) {return "login";}// 根据票据来获取用户信息User user = (User) session.getAttribute(ticket);if (null == user) {return "login";}// 将用户信息存入model中，返回到前端model.addAttribute("user", user);return "goodsList";}
}

2.商品列表页goodsList.html

<!DOCTYPE html>
<html lang="en" xmlns:th="http://www.thymeleaf.org">
<head><meta charset="UTF-8"><title>商品列表</title>
</head>
<body>
<h1>商品列表</h1>
<p th:text="'hi: ' + ${user.nickname}"></p>
</body>
</html>

3.测试登录成功后进入商品列表页

2.分布式session解决方案

1.session绑定/粘滞（不常用）

2.session复制

3.前端存储

4.后端集中存储

3.方案一：SpringSession实现分布式Session

1.安装使用redis-desktop-manager

1.一直下一步，安装到D盘

2.首先要确保redis集群的端口是开放的并使其支持远程访问（之前配置过）

3.使用telnet指令测试某个服务是否能够连接成功

telnet 140.143.164.206 7489

4.连接Redis，先测试连接然后确定

5.在redis命令行设置两个键

6.在可视化工具查看

2.项目整合Redis并配置分布式session

1.pom.xml引入依赖

        <!--spring data redis 依赖, 即 spring 整合 redis--><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-data-redis</artifactId><version>2.4.5</version></dependency><!--pool2 对象池依赖--><dependency><groupId>org.apache.commons</groupId><artifactId>commons-pool2</artifactId><version>2.9.0</version></dependency><!--实现分布式 session, 即将 Session 保存到指定的 Redis--><dependency><groupId>org.springframework.session</groupId><artifactId>spring-session-data-redis</artifactId></dependency>

2.application.yml配置Redis

spring:redis:password:  # Redis服务器密码database: 0 # 默认数据库为0号timeout: 10000ms # 连接超时时间是10000毫秒lettuce:pool:max-active: 8 # 最大活跃连接数,使用负值表示没有限制，最佳配置为核数*2max-wait: 10000ms # 最大等待时间,单位为毫秒,使用负值表示没有限制，这里设置为10秒max-idle: 200 # 最大空闲连接数min-idle: 5 # 最小空闲连接数cluster:nodes:- - 

3.启动测试

1.登录

2.Redis可视化工具发现session成功存到redis

4.方案二：统一存放用户信息到Redis

1.修改pom.xml，去掉分布式springsession的依赖

2.将用户信息放到Redis

1.添加Redis配置类 com/sxs/seckill/config/RedisConfig.java

package com.sxs.seckill.config;import com.fasterxml.jackson.annotation.JsonAutoDetect;
import com.fasterxml.jackson.annotation.JsonTypeInfo;
import com.fasterxml.jackson.annotation.PropertyAccessor;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.jsontype.impl.LaissezFaireSubTypeValidator;
import org.springframework.cache.CacheManager;
import org.springframework.cache.annotation.CachingConfigurerSupport;
import org.springframework.cache.annotation.EnableCaching;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.redis.cache.RedisCacheConfiguration;
import org.springframework.data.redis.cache.RedisCacheManager;
import org.springframework.data.redis.connection.RedisConnectionFactory;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.data.redis.serializer.Jackson2JsonRedisSerializer;
import org.springframework.data.redis.serializer.RedisSerializationContext;
import org.springframework.data.redis.serializer.RedisSerializer;
import org.springframework.data.redis.serializer.StringRedisSerializer;import java.time.Duration;/*** Description:** @Author sun* @Create 2024/4/29 21:29* @Version 1.0*/
@EnableCaching
@Configuration
public class RedisConfig extends CachingConfigurerSupport {@Beanpublic RedisTemplate<String, Object> redisTemplate(RedisConnectionFactory factory) {RedisTemplate<String, Object> template =new RedisTemplate<>();System.out.println("template=>" + template);RedisSerializer<String> redisSerializer =new StringRedisSerializer();Jackson2JsonRedisSerializer jackson2JsonRedisSerializer =new Jackson2JsonRedisSerializer(Object.class);ObjectMapper om = new ObjectMapper();om.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.ANY);om.activateDefaultTyping(LaissezFaireSubTypeValidator.instance, ObjectMapper.DefaultTyping.NON_FINAL, JsonTypeInfo.As.WRAPPER_ARRAY);jackson2JsonRedisSerializer.setObjectMapper(om);template.setConnectionFactory(factory);// key 序列化方式template.setKeySerializer(redisSerializer);// value 序列化template.setValueSerializer(jackson2JsonRedisSerializer);// value hashmap 序列化template.setHashValueSerializer(jackson2JsonRedisSerializer);return template;}@Beanpublic CacheManager cacheManager(RedisConnectionFactory factory) {RedisSerializer<String> redisSerializer =new StringRedisSerializer();Jackson2JsonRedisSerializer jackson2JsonRedisSerializer = newJackson2JsonRedisSerializer(Object.class);// 解决查询缓存转换异常的问题ObjectMapper om = new ObjectMapper();om.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.ANY);om.activateDefaultTyping(LaissezFaireSubTypeValidator.instance, ObjectMapper.DefaultTyping.NON_FINAL, JsonTypeInfo.As.WRAPPER_ARRAY);jackson2JsonRedisSerializer.setObjectMapper(om);// 配置序列化（解决乱码的问题）,过期时间 600 秒RedisCacheConfiguration config = RedisCacheConfiguration.defaultCacheConfig().entryTtl(Duration.ofSeconds(600)).serializeKeysWith(RedisSerializationContext.SerializationPair.fromSerializer(redisSerializer)).serializeValuesWith(RedisSerializationContext.SerializationPair.fromSerializer(jackson2JsonRedisSerializer)).disableCachingNullValues();RedisCacheManager cacheManager = RedisCacheManager.builder(factory).cacheDefaults(config).build();return cacheManager;}
}

2.修改 com/sxs/seckill/service/impl/UserServiceImpl.java

1.注入RedisTemplate

2.修改doLogin方法，将用户信息放到Redis中

3.启动测试

1.登录

2.可视化工具查看用户信息

3.实现使用Redis + Cookie实现登录，可以访问商品列表页面

1.刚才已经实现了Redis记录信息的功能，但是校验还没实现，修改GoodsController.java完成校验

1.注入RedisTemplate

2.从Redis中获取校验信息，进行校验

2.测试

1.登录成功后访问商品列表页面

5.扩展：自定义参数解析器，直接获取User

1.修改 com/sxs/seckill/controller/GoodsController.java 使参数直接为User

    // 进入到商品首页@RequestMapping("/toList")public String toList(Model model, User user) {// 判断是否有用户信息if (null == user) {return "login";}// 将用户信息存入model中，返回到前端model.addAttribute("user", user);return "goodsList";}

2.service层添加方法，通过票据从Redis中获取User对象

1.UserService.java

    /*** 根据cookie获取用户* @param userTicket* @param request* @param response* @return*/public User getUserByCookie(String userTicket, HttpServletRequest request, HttpServletResponse response);

2.UserServiceImpl.java

• 这里需要注意，每次获取完User，需要重新设置Cookie，来刷新Cookie的时间
• 原因是，调用这个的目的是为了校验，而用户访问每个页面都要进行校验，如果每次校验之后都不刷新Cookie的时间，一旦Cookie失效了，用户就要重新登陆

    @Overridepublic User getUserByCookie(String userTicket, HttpServletRequest request, HttpServletResponse response) {// 判断是否有票据if (null == userTicket) {return null;}// 根据票据来获取用户信息，从redis中获取User user = (User) redisTemplate.opsForValue().get("user:" + userTicket);if (null == user) {return null;}// 重新设置cookie的有效时间CookieUtil.setCookie(request, response, "userTicket", userTicket);return user;}

3.编写自定义参数解析器对User类型参数进行解析 config/UserArgumentResolver.java

package com.sxs.seckill.config;import com.sxs.seckill.pojo.User;
import com.sxs.seckill.service.UserService;
import com.sxs.seckill.utils.CookieUtil;
import org.springframework.core.MethodParameter;
import org.springframework.stereotype.Component;
import org.springframework.web.bind.support.WebDataBinderFactory;
import org.springframework.web.context.request.NativeWebRequest;
import org.springframework.web.method.support.HandlerMethodArgumentResolver;
import org.springframework.web.method.support.ModelAndViewContainer;import javax.annotation.Resource;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;/*** Description: 自定义参数解析器** @Author sun* @Create 2024/5/7 14:39* @Version 1.0*/
@Component
public class UserArgumentResolver implements HandlerMethodArgumentResolver {@Resourceprivate UserService userService;/** 判断是否支持要转换的参数类型，简单来说，就是在这里设置要解析的参数类型*/@Overridepublic boolean supportsParameter(MethodParameter methodParameter) {// 如果参数类型是User，则进行解析Class<?> parameterType = methodParameter.getParameterType();if (parameterType == User.class) {return true;}return false;}/*** 编写参数解析的逻辑** @param methodParameter* @param modelAndViewContainer* @param nativeWebRequest* @param webDataBinderFactory* @return* @throws Exception*/@Overridepublic Object resolveArgument(MethodParameter methodParameter, ModelAndViewContainer modelAndViewContainer, NativeWebRequest nativeWebRequest, WebDataBinderFactory webDataBinderFactory) throws Exception {// 首先获取request和responseHttpServletRequest request = nativeWebRequest.getNativeRequest(HttpServletRequest.class);HttpServletResponse response = nativeWebRequest.getNativeResponse(HttpServletResponse.class);// 从cookie中获取票据String userTicket = CookieUtil.getCookieValue(request, "userTicket");// 如果票据为空，则返回nullif (null == userTicket) {return null;}// 如果票据不为空，则根据票据获取用户信息User user = this.userService.getUserByCookie(userTicket, request, response);return user;}
}

4.编写config/WebConfig.java 将自定义参数解析器放到 resolvers 才能生效

package com.sxs.seckill.config;import org.springframework.context.annotation.Configuration;
import org.springframework.web.method.support.HandlerMethodArgumentResolver;
import org.springframework.web.servlet.config.annotation.EnableWebMvc;
import org.springframework.web.servlet.config.annotation.ResourceHandlerRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;import javax.annotation.Resource;
import java.util.List;/*** Description:** @Author sun* @Create 2024/5/7 14:53* @Version 1.0*/
@Configuration
// @EnableWebMvc 使用这个注解会导致SpringBoot的自动配置失效，一切都要自己配置，所以建议不要使用这个注解
public class WebConfig implements WebMvcConfigurer {// 注入自定义参数解析器@Resourceprivate UserArgumentResolver userArgumentResolver;/*** 静态资源加载，静态资源放在哪里就怎么配置* @param registry*/@Overridepublic void addResourceHandlers(ResourceHandlerRegistry registry) {registry.addResourceHandler("/**").addResourceLocations("classpath:/static/");}/*** 添加自定义参数解析器到resolvers中，才能生效* @param resolvers*/@Overridepublic void addArgumentResolvers(List<HandlerMethodArgumentResolver> resolvers) {resolvers.add(userArgumentResolver);}
}

5.测试

1.在登录之后，可以正常访问商品列表页面