spring-session解决session一致性问题

1.新建Maven项目，pom.xml加入如下：

		org.springframework.boot
		spring-boot-starter-parent
		2.0.0.RELEASE
		 
	
	
	
		2.8.0
		1.8
		1.8
		UTF-8
		UTF-8
		zh_CN
	

	
		
			org.projectlombok
			lombok
		
		
			org.springframework.boot
			spring-boot-starter-web
			
		
		
		
			com.alibaba
			fastjson
			1.2.47
		
		
		
			org.springframework.boot
			spring-boot-starter-test
			test
		
		
			org.springframework.boot
			spring-boot-starter-data-redis
		
		
		
			org.springframework.session
			spring-session-data-redis
		
		
			org.apache.commons
			commons-pool2
		
		
			redis.clients
			jedis
		

	
	
		
			
				org.apache.maven.plugins
				maven-compiler-plugin
				
					1.8
					1.8
				
			
			
				org.springframework.boot
				spring-boot-maven-plugin
				
					com.meiteedu.WxMpApplication
				
				
					
						
							repackage
						
					
				

			
		
	

2.新建redis的配置类

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
 * 
 * @author mayn
 *
 */
// 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}")
	int port;
	
	@Value("${redis.password}")
	String password;

	@SuppressWarnings("deprecation")
	@Bean
	public JedisConnectionFactory connectionFactory() {
		JedisConnectionFactory connection = new JedisConnectionFactory();
		connection.setPort(port);
		connection.setHostName(hostName);
		connection.setPassword(password);
		return connection;
	}
}

3.新建初始化redis配置类

import org.springframework.session.web.context.AbstractHttpSessionApplicationInitializer;

//初始化Session配置
public class SessionInitializer extends AbstractHttpSessionApplicationInitializer{
    public SessionInitializer() {
        super(SessionConfig.class);
    }
}

4.新建一个启动类

@SpringBootApplication
@RestController
public class TestSessionApp {
	
	@Value("${server.port}")
	private String serverPort;

	// 创建session 会话
	// http://127.0.0.1:8080/createSession?name=aaa
	@RequestMapping("/createSession")
	public String createSession(HttpServletRequest request, String name) {
		HttpSession session = request.getSession();
		System.out.println("存入Session sessionid:信息" + session.getId() + ",name:" + name + ",serverPort:" + serverPort);
		session.setAttribute("name", name);
		return serverPort + "success";
	}

	// 获取session 会话
	@RequestMapping("/getSession")
	public Object getSession(HttpServletRequest request) {
		// 参数为true的情况下，客户端使用对应的sessionid查不到对应的session，会创建一个新的session
		// 参数为false的情况下，客户端使用对应的sessionid查不到对应的session，不会创建一个新的session
		HttpSession session = request.getSession(false);
		
		if (session == null) {
			return serverPort + "服务器上没有session...";
		}
		
		System.out.println("获取Session sessionid:信息" + session.getId() + ",serverPort:" + serverPort);
		Object value = session.getAttribute("name");
		return serverPort + "-" + value;
	}
	
	@RequestMapping("/getServerPort")
	public String getServerPort () {
		return serverPort;
	}

	public static void main(String[] args) {
		SpringApplication.run(TestSessionApp.class, args);
	}
}

5.启动两个集群环境，端口号分别为8080和8081

访问http://127.0.0.1:8080/createSession?name=aaa，往8080服务器session上存取数据

此时8081服务器的session也可以拿到8080服务器存取的数据了

查看redis，session保存在redis里面