Shiro权限框架-Realm缓存机制（6）

1、Realm缓存机制意义

在上面我们自定了自己的realm，但是我们发现

在认证和授权的时候，程序需要频繁的访问数据库，这样对于数据库的压力可想而知，那我们怎么处理呢？

2、Realm缓存机制实现思路

【1】缓存机制图解

【2】原理分析

此时我们对UserBridgeServiceImpl的实现类里面的逻辑加入了自定义的SimpleCacheService缓存服务接口，简单来说实现了在认证和鉴权时不需要每次都去查询数据库，而是把认证和鉴权信息放入到redis缓存中，以减低数据库的访问压力

1、集成redis服务器，作为集中存储认证和鉴权信息
2、改写UserBridgeServiceImpl使其优先从缓存中读取

3、redission集成

【1】添加ShiroRedisProperties

此类主要负责yaml文件的配置类

package com.newbies.shiro.config;

import lombok.Data;
import org.springframework.boot.context.properties.ConfigurationProperties;

import java.io.Serializable;

/**
 * @Description  redis配置文件
 */
@Data
@ConfigurationProperties(prefix = "itheima.framework.shiro.redis")
public class ShiroRedisProperties implements Serializable {

	/**
	 * redis连接地址
	 */
	private String nodes ;

	/**
	 * 获取连接超时时间
	 */
	private int connectTimeout ;

	/**
	 * 连接池大小
	 */
	private int connectPoolSize;

	/**
	 * 初始化连接数
	 */
	private int connectionMinimumidleSize ;

	/**
	 * 等待数据返回超时时间
	 */
	private int timeout ;

	/**
	 *  全局超时时间
	 */
	private long globalSessionTimeout;

}

【2】编辑ShiroConfig

集成redisson的相关配置，同时启用ShiroRedisProperties的配置

package com.newbies.shiro.config;


import com.newbies.shiro.core.ShiroDbRealm;
import com.newbies.shiro.core.impl.ShiroDbRealmImpl;
import com.newbies.shiro.filter.RolesOrAuthorizationFilter;
import com.newbies.shiro.properties.PropertiesUtil;
import lombok.extern.log4j.Log4j2;
import org.apache.shiro.spring.LifecycleBeanPostProcessor;
import org.apache.shiro.spring.security.interceptor.AuthorizationAttributeSourceAdvisor;
import org.apache.shiro.spring.web.ShiroFilterFactoryBean;
import org.apache.shiro.web.mgt.DefaultWebSecurityManager;
import org.apache.shiro.web.servlet.SimpleCookie;
import org.apache.shiro.web.session.mgt.DefaultWebSessionManager;
import org.redisson.Redisson;
import org.redisson.api.RedissonClient;
import org.redisson.config.Config;
import org.springframework.aop.framework.autoproxy.DefaultAdvisorAutoProxyCreator;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.context.properties.EnableConfigurationProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.DependsOn;

import javax.servlet.Filter;
import java.util.HashMap;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;

/**
 * @Description 权限配置类
 */
@Configuration
@ComponentScan(basePackages = "com.itheima.shiro.core")
@EnableConfigurationProperties({ShiroRedisProperties.class})
@Log4j2
public class ShiroConfig {

    @Autowired
    private ShiroRedisProperties shiroRedisProperties;

    /**
     * @Description redission客户端
     */
    @Bean("redissonClientForShiro")
    public RedissonClient redissonClient() {
        log.info("=====初始化redissonClientForShiro开始======");
        String[] nodeList = shiroRedisProperties.getNodes().split(",");
        Config config = new Config();
        if (nodeList.length == 1) {
            config.useSingleServer().setAddress(nodeList[0])
                    .setConnectTimeout(shiroRedisProperties.getConnectTimeout())
                    .setConnectionMinimumIdleSize(shiroRedisProperties.getConnectionMinimumidleSize())
                    .setConnectionPoolSize(shiroRedisProperties.getConnectPoolSize()).setTimeout(shiroRedisProperties.getTimeout());
        } else {
            config.useClusterServers().addNodeAddress(nodeList)
                    .setConnectTimeout(shiroRedisProperties.getConnectTimeout())
                    .setMasterConnectionMinimumIdleSize(shiroRedisProperties.getConnectionMinimumidleSize())
                    .setMasterConnectionPoolSize(shiroRedisProperties.getConnectPoolSize()).setTimeout(shiroRedisProperties.getTimeout());
        }
        RedissonClient redissonClient =  Redisson.create(config);
        log.info("=====初始化redissonClientForShiro完成======");
        return redissonClient;
    }

    /**
     * @Description 创建cookie对象
     */
    @Bean(name="sessionIdCookie")
    public SimpleCookie simpleCookie(){
        SimpleCookie simpleCookie = new SimpleCookie();
        simpleCookie.setName("ShiroSession");
        return simpleCookie;
    }

    /**
     * @Description 权限管理器
     * @param
     * @return
     */
    @Bean(name="securityManager")
    public DefaultWebSecurityManager defaultWebSecurityManager(){
        DefaultWebSecurityManager securityManager = new DefaultWebSecurityManager();
        securityManager.setRealm(shiro