2021-11-11Springboot实现分布式session

2021-11-11Springboot实现分布式session

Springboot集成redis实现分布式session

• • 步骤

步骤

1。导入相关依赖，配置yml

            org.springframework.boot
            spring-boot-starter-data-redis
        
        
            org.springframework.boot
            spring-boot-starter-test
        
        
            org.springframework.session
            spring-session-core
        
        
            org.springframework.session
            spring-session-data-redis
        

  redis:
    host: localhost
    port: 6379
    jedis.pool.max-idle: 100
    jedis.pool.max-wait: -1ms
    jedis.pool.min-idle: 2
    timeout: 2000m

2.启动类上加入注解
@EnableRedisHttpSession

import org.springframework.session.data.redis.config.annotation.web.http.EnableRedisHttpSession;
import springfox.documentation.swagger2.annotations.EnableSwagger2;
import tk.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;

import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
@MapperScan("com.fzw.dao")
@EnableSwagger2
@EnableRedisHttpSession
public class Application {
    public static void main(String[] args) {
        SpringApplication.run(Application.class,args);}
}

3.在controller的方法上传入HttpServletRequest对象，例如本例中希望实现第一次登录是从数据库中查询数据，但是后面再次访问时，从redis缓存中获取数据，这样减少数据库的压力

@ApiOperation(value = "登录 ",notes = "登录 ")
@PostMapping("/login")
public Result login(@RequestBody BookUser bookUser, HttpServletRequest request) {
    List list=bookUserService.select(bookUser);
    if(list.size()>0){
        if(request.getAttribute("flag")==null){ //第一次登录
            request.getSession().setAttribute("flag","true");
            System.out.println(request.getSession().getAttribute("flag"));
        }
        return new Result(true,200,"登录成功");
    }else{

        return new Result(true,500,"用户名或密码错误");
    }
}
}

service层

  public PageInfo findAllByPage(Integer currentPage, Integer pageSize, HttpServletRequest request) {
       PageHelper.startPage(currentPage, pageSize);
       PageInfo pageInfo = new PageInfo<>();
       Object flag = request.getSession().getAttribute("flag");
       System.out.println(request.getSession().getAttribute("flag"));
       if (flag==null|| "true".equals(flag)) {  //第一次 登录
           // 通过数据库查询
           List bookList = bookMapper.selectAll();
           pageInfo = new PageInfo(bookList);
           System.out.println("走数据库");
           request.getSession().setAttribute("booklist", bookList);
           request.getSession().setAttribute("flag", "false");
       } else {
           //通过 redis查询
           // 封装PageInfo 对象
           pageInfo = new PageInfo((List) request.getSession().getAttribute("booklist"));
           System.out.println("走redis");
       }
       System.out.println("pageInfo的 值" + pageInfo);
       return pageInfo;
   }

在访问到该地址后，redis会自动创建redis对象

同时启动多个Springboot应用测试

本例中通过nginx实现负载均衡，nginx配置如下
nginx.conf

代码还是有些问题的，欢迎大家评论交流。