一、首先Session
Session 是客户端与服务器通讯会话技术, 比如浏览器登陆、记录整个浏览会话信息。session存放在服务器,关闭浏览器不会失效。
Session实现原理
客户对向服务器端发送请求后,Session 创建在服务器端,返回Sessionid给客户端浏览器保存在本地,当下次发送请求的时候,在请求头中传递sessionId获取对应的从服务器上获取对应的Sesison
请求过程:
服务器端接受到客户端请求,会创建一个session,使用响应头返回 sessionId给客户端。客户端获取到sessionId后,保存到本地。
下次请求:客户端将本地的sessionId通过请求头发送到服务器。服务器从请求头获取到对应的sessionId,使用sessionId在本地session内存中查询。
HttpSession session = request.getSession(); //默认创建一个session 默认值为true 没有找到对应的session 自动创建session
HttpSession session = request.getSession(false) //true的情况是 客户端使用对应的sessionId查询不到对应的session 会直接创建一个新的session 如果有的话直接覆盖之前的
//false 客户端使用对应的sessionId查询不到对应的session 不会创建新的session
session 包括 sessionId和sessionValue
session本身是临时的 token(令牌)与 sessionId很相似 保证了临时且唯一
玩下session:
前提需要安装nginx
配置如下:
host文件:c:/windows/system32/drivers/etc
访问 blog.ytso.com时候 走的nginx的服务器域名 然后默认监听的端口号80。 进而通过配置upstream 负载均衡!
lz在玩时候,弄到了半夜,也没排查出来原因,妈的气死了! 地址写成了 127.0.0.1
yml:
server: port: 8080
pom:
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>com.toov5.loveCode</groupId> <artifactId>loveCode</artifactId> <version>0.0.1-SNAPSHOT</version> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.0.0.RELEASE</version> <relativePath /> <!-- lookup parent from repository --> </parent> <properties> <weixin-java-mp.version>2.8.0</weixin-java-mp.version> <maven.compiler.source>1.8</maven.compiler.source> <maven.compiler.target>1.8</maven.compiler.target> <maven.compiler.encoding>UTF-8</maven.compiler.encoding> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> <project.build.locales>zh_CN</project.build.locales> </properties> <dependencies> <dependency> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> <!-- <exclusions> <exclusion> <groupId>com.fasterxml.jackson.core</groupId> <artifactId>jackson-databind</artifactId> </exclusion> </exclusions> --> </dependency> <!-- https://mvnrepository.com/artifact/com.alibaba/fastjson --> <dependency> <groupId>com.alibaba</groupId> <artifactId>fastjson</artifactId> <version>1.2.47</version> </dependency> <!-- Testing Dependencies --> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-redis</artifactId> </dependency> <!--spring session 与redis应用基本环境配置,需要开启redis后才可以使用,不然启动Spring boot会报错 --> <!-- <dependency> <groupId>org.springframework.session</groupId> <artifactId>spring-session-data-redis</artifactId> </dependency> --> <dependency> <groupId>org.apache.commons</groupId> <artifactId>commons-pool2</artifactId> </dependency> <dependency> <groupId>redis.clients</groupId> <artifactId>jedis</artifactId> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-compiler-plugin</artifactId> <configuration> <source>1.8</source> <target>1.8</target> </configuration> </plugin> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> <configuration> <maimClass>com.meiteedu.WxMpApplication</maimClass> </configuration> <executions> <execution> <goals> <goal>repackage</goal> </goals> </execution> </executions> </plugin> </plugins> </build> </project>
服务器端代码:
package com.toov5.loveCode; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpSession; import org.springframework.beans.factory.annotation.Value; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RestController; @SpringBootApplication @RestController public class TestSessionController { @Value("${server.port}") private String serverPort; @RequestMapping("/") public String index() { return serverPort; } // 创建session 会话 @RequestMapping("/createSession") public String createSession(HttpServletRequest request, String nameValue) { // 默认 创建一个session, HttpSession session = request.getSession(); System.out.println( "存入Session sessionid:信息" + session.getId() + ",nameValue:" + nameValue + ",serverPort:" + serverPort); session.setAttribute("name", nameValue); return "success-" + serverPort; } // 获取session 会话 @RequestMapping("/getSession") public Object getSession(HttpServletRequest request) { // 设置为true 情况下的时候,客户端使用对应的sessionid 查询不到对应的sesison 会直接创建一个新的session // 设置为false 情况下的时候,客户端使用对应的sessionid 查询不到对应的sesison 不 会直接创建一个新的session HttpSession session = request.getSession(true); if (session == null) { return serverPort + " 该服务器上没有存放对应的session值"; } System.out.println("获取Session sessionid:信息" + session.getId() + "serverPort:" + serverPort); Object value = session.getAttribute("name"); return serverPort + "-" + value; } }
启动类:启动两次 端口号修改8080、 8081
package com.toov5.loveCode; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.EnableAutoConfiguration; import org.springframework.boot.autoconfigure.SpringBootApplication; @EnableAutoConfiguration @SpringBootApplication public class AppSession { public static void main(String[] args) { SpringApplication.run(AppSession.class, args); } }
运行结果:8080 和 8081来回切换 负载均衡
调用服务器端方法: fist 存放在8080
查询不到哦!
8081 没有 就创建新的session 覆盖原来的sessionId true没有就创建
下次 又去8080 又没有 又创建 来回折腾…………..
此时:
修改false 没有时候不创建
然后传入 value 然后继续轮训访问;
二、分布式Session
1、直接使用cookie替代session 不安全(存客户端)
2、Nginx的IP绑定 目的是同一个IP只能指定同一个机器访问(相当于没做集群了)
3、 使用数据库(效率低)
4、tomcat内置Session同步,通过广播可能产生延迟,占用带宽
5、使用 Spring-Session框架,相当于把session缓存缓存到redis中 ( 缓存框架,缓存Session的值 )
6、可以使用token替代session功能。自定义令牌替代session
Spring-Session 重写httpsession框架,将对应的值缓存到redis中,有点类似于一级、二级缓存。
必须要有的!
yml文件:
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>com.toov5.loveCode</groupId> <artifactId>loveCode</artifactId> <version>0.0.1-SNAPSHOT</version> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.0.0.RELEASE</version> <relativePath /> <!-- lookup parent from repository --> </parent> <properties> <weixin-java-mp.version>2.8.0</weixin-java-mp.version> <maven.compiler.source>1.8</maven.compiler.source> <maven.compiler.target>1.8</maven.compiler.target> <maven.compiler.encoding>UTF-8</maven.compiler.encoding> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> <project.build.locales>zh_CN</project.build.locales> </properties> <dependencies> <dependency> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> <!-- <exclusions> <exclusion> <groupId>com.fasterxml.jackson.core</groupId> <artifactId>jackson-databind</artifactId> </exclusion> </exclusions> --> </dependency> <!-- https://mvnrepository.com/artifact/com.alibaba/fastjson --> <dependency> <groupId>com.alibaba</groupId> <artifactId>fastjson</artifactId> <version>1.2.47</version> </dependency> <!-- Testing Dependencies --> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-redis</artifactId> </dependency> <!--spring session 与redis应用基本环境配置,需要开启redis后才可以使用,不然启动Spring boot会报错 --> <dependency> <groupId>org.springframework.session</groupId> <artifactId>spring-session-data-redis</artifactId> </dependency> <dependency> <groupId>org.apache.commons</groupId> <artifactId>commons-pool2</artifactId> </dependency> <dependency> <groupId>redis.clients</groupId> <artifactId>jedis</artifactId> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-compiler-plugin</artifactId> <configuration> <source>1.8</source> <target>1.8</target> </configuration> </plugin> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> <configuration> <maimClass>com.meiteedu.WxMpApplication</maimClass> </configuration> <executions> <execution> <goals> <goal>repackage</goal> </goals> </execution> </executions> </plugin> </plugins> </build> </project>
非常非常重要的:一定要jredis引入 同时这个对session提供了大力支持哈哈
yml 的redis配置文件:
server: port: 8080 redis: hostname: 192.168.91.3 port: 6379 password: 123
后台业务逻辑:
package com.toov5.loveCode; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpSession; import org.springframework.beans.factory.annotation.Value; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RestController; @SpringBootApplication @RestController public class TestSessionController { @Value("${server.port}") private String serverPort; @RequestMapping("/") public String index() { return serverPort; } // 创建session 会话 @RequestMapping("/createSession") public String createSession(HttpServletRequest request, String nameValue) { // 默认 创建一个session, HttpSession session = request.getSession(); System.out.println( "存入Session sessionid:信息" + session.getId() + ",nameValue:" + nameValue + ",serverPort:" + serverPort); session.setAttribute("name", nameValue); return "success-" + serverPort; } // 获取session 会话 @RequestMapping("/getSession") public Object getSession(HttpServletRequest request) { // 设置为true 情况下的时候,客户端使用对应的sessionid 查询不到对应的sesison 会直接创建一个新的session // 设置为false 情况下的时候,客户端使用对应的sessionid 查询不到对应的sesison 不 会直接创建一个新的session HttpSession session = request.getSession(false); if (session == null) { return serverPort + " 该服务器上没有存放对应的session值"; } System.out.println("获取Session sessionid:信息" + session.getId() + "serverPort:" + serverPort); Object value = session.getAttribute("name"); return serverPort + "-" + value; } }
配置:
package com.toov5.loveCode; import org.springframework.beans.factory.annotation.Value; import org.springframework.context.annotation.Bean; import org.springframework.data.redis.connection.jedis.JedisConnectionFactory; import org.springframework.session.data.redis.config.annotation.web.http.EnableRedisHttpSession; //这个类用配置redis服务器的连接 //maxInactiveIntervalInSeconds为SpringSession的过期时间(单位:秒) @EnableRedisHttpSession(maxInactiveIntervalInSeconds = 1800) public class SessionConfig { // 冒号后的值为没有配置文件时,制动装载的默认值 @Value("${redis.hostname:localhost}") String HostName; @Value("${redis.port:6379}") int Port; @Value("${redis.password}") String password; @Bean public JedisConnectionFactory connectionFactory() { JedisConnectionFactory connection = new JedisConnectionFactory(); connection.setPort(Port); connection.setHostName(HostName); connection.setPassword(password); return connection; } }
初始化:
package com.toov5.loveCode; import org.springframework.session.web.context.AbstractHttpSessionApplicationInitializer; //初始化Session配置 public class SessionInitializer extends AbstractHttpSessionApplicationInitializer{ public SessionInitializer() { super(SessionConfig.class); } }
启动类:
package com.toov5.loveCode; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.EnableAutoConfiguration; import org.springframework.boot.autoconfigure.SpringBootApplication; @EnableAutoConfiguration @SpringBootApplication public class AppSession { public static void main(String[] args) { SpringApplication.run(AppSession.class, args); } }
虽然是存放在8081,但是访问时候 都有哦~ 大家试试玩玩吧~~
引入的jar包重写了 HttpSession类 去解决Session共享问题
而此时的:redis
控制台:
补充:
Spring Boot 整合redis:
server: port: 8080 spring: redis: database: 0 host: 192.168.91.3 port: 6379 password: 123 jedis: pool: max-active: 8 max-wait: -1 max-idle: 8 min-idle: 0 timeout: 10000 redis: hostname: 192.168.91.3 port: 6379 password: 123
原创文章,作者:奋斗,如若转载,请注明出处:https://blog.ytso.com/16141.html