1.背景

上次发了这篇文章《Spring Boot集成Shiro快速入门Demo》后,有网友“just.blue”后台反馈集成redis有点问题,今天特地把集成过程发出来

2.为什么要使用cache

用来减轻数据库的访问压力,从而提升查询效率。

3.Shiro使用Redis做缓存

redis环境准备

参照代码工程li面redis模块里面docker,按照要求启动即可

引入pom,xml

<!-- https://mvnrepository.com/artifact/org.springframework.boot/spring-boot-starter-data-redis -->
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-data-redis</artifactId>
</dependency>

redis配置

spring:
  redis:
    database: 0
    port: 6379
    host: 127.0.0.1
    password: 123456
    timeout=3000:
    jedis:
      pool:
        max-active: 8
        max-idle: 8
        max-wait: -1
        min-idle: 0

cache接口实现

创建RedisCacheManager实现CacheManager接口

package com.et.shiro.cache;

import org.apache.shiro.cache.Cache;
import org.apache.shiro.cache.CacheException;
import org.apache.shiro.cache.CacheManager;

public class RedisCacheManager implements CacheManager {
    @Override
    public <K, V> Cache<K, V> getCache(String cacheKey) throws CacheException {
        return new RedisCache<>(cacheKey);
    }
}

创建RedisCache实现Cache接口

package com.et.shiro.cache;

import org.apache.shiro.cache.Cache;
import org.apache.shiro.cache.CacheException;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.data.redis.serializer.StringRedisSerializer;

import java.util.Collection;
import java.util.Set;

public class RedisCache<K, V> implements Cache<K, V> {
    private String cacheName;

    public RedisCache() {
    }

    public RedisCache(String cacheName) {
        this.cacheName = cacheName;
    }


    private RedisTemplate getRedisTemplate() {
        RedisTemplate redisTemplate = (RedisTemplate) ApplicationContextUtil.getBean("redisTemplate");
        redisTemplate.setKeySerializer(new StringRedisSerializer());
        redisTemplate.setHashKeySerializer(new StringRedisSerializer());
        return redisTemplate;
    }

    @Override
    public V get(K k) throws CacheException {

        return (V) getRedisTemplate().opsForHash().get(this.cacheName,k.toString());

    }

    @Override
    public V put(K k, V v) throws CacheException {

        getRedisTemplate().opsForHash().put(this.cacheName,k.toString(), v);
        return null;
    }

     @Override
    public V remove(K k) throws CacheException {

        return (V) getRedisTemplate().opsForHash().delete(this.cacheName,k.toString());
    }

    @Override
    public void clear() throws CacheException {
        getRedisTemplate().opsForHash().delete(this.cacheName);
    }

    @Override
    public int size() {
        return getRedisTemplate().opsForHash().size(this.cacheName).intValue();
    }

    @Override
    public Set<K> keys() {
        return getRedisTemplate().opsForHash().keys(this.cacheName);
    }

    @Override
    public Collection<V> values() {
        return getRedisTemplate().opsForHash().values(this.cacheName);
    }
}

获取bean工具类

package com.et.shiro.cache;

import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.stereotype.Component;

@Component
public class ApplicationContextUtil implements ApplicationContextAware {

    private static ApplicationContext applicationContext;

    @Override
    public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
        this.applicationContext = applicationContext;
    }

    public static <T> T getBean(String beanName) {
        return (T)applicationContext.getBean(beanName);
    }

    public static <T> T getBean(Class<T> className) {
        return applicationContext.getBean(className);
    }
}

由于自定义realm中认证所需要的盐值内部并没有实现序列化接口,所以我们需要自己定一个MyByteSource继承SimpleByteSource并实现Serializable接口

package com.et.shiro.config;

import org.apache.shiro.util.SimpleByteSource;

import java.io.Serializable;

public class MyByteSource extends SimpleByteSource implements Serializable {
    public MyByteSource(String string) {
        super(string);
    }
}

在自定义的Realm中需要在认证的方法中,改写salt的处理。

@Override
protected AuthenticationInfo doGetAuthenticationInfo(AuthenticationToken token)
        throws AuthenticationException {
    System.out.println("MyShiroRealm.doGetAuthenticationInfo()");
    String username = (String)token.getPrincipal();
    System.out.println(token.getCredentials());
    //query user by username
    //in here ,you can cache some data for efficient
    UserInfo userInfo = userInfoService.findByUsername(username);
    System.out.println("----->>userInfo="+userInfo);
    if(userInfo == null){
        return null;
    }
    SimpleAuthenticationInfo authenticationInfo = new SimpleAuthenticationInfo(
            userInfo, //username
            userInfo.getPassword(), //password
            new MyByteSource(userInfo.getCredentialsSalt()),
            //ByteSource.Util.bytes(userInfo.getCredentialsSalt()),//salt=username+salt
            getName()  //realm name
    );
    return authenticationInfo;
}

注意实体类(角色类,用户类,权限类)要记得实现Serializable接口 最后在Shiro配置类中开启缓存,使用我们自己定义的RedisManager

@Bean
public MyShiroRealm myShiroRealm(){
   MyShiroRealm myShiroRealm = new MyShiroRealm();
   myShiroRealm.setCredentialsMatcher(hashedCredentialsMatcher());// 设置解密规则
   // 开启全局缓存
   myShiroRealm.setCachingEnabled(true);
   // 开启认证缓存
   myShiroRealm.setAuthenticationCachingEnabled(true);
   // 设置认证缓存管理的名字
   myShiroRealm.setAuthenticationCacheName("authenticationCache");
   // 开启授权缓存管理
   myShiroRealm.setAuthorizationCachingEnabled(true);
   // 设置授权缓存管理的名字
   myShiroRealm.setAuthorizationCacheName("authorizationCache");
   // 开启Redis缓存
   myShiroRealm.setCacheManager(new RedisCacheManager());
   return myShiroRealm;
}

以上只是一些关键代码,所有代码请参见下面代码仓库

代码仓库

4.测试

启动项目,访问http://127.0.0.1:8088/userInfo/userAdd,会跳转到登录页,输入admin 123456,查看redis是否缓存了

538

登录用户,第一次会从数据库中查询,并通过RedisTemplate的put方法将用户信息装入缓存,下次再刷新首页就会从redis中查询权限,授权等信息。退出时会调用RedisTemplate中的remove方法清除向对应的用户缓存。

5.引用

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