Bug：SpringBoot整合SpringCache与Redis踩过的坑-蒲公英云

Bug：SpringBoot整合SpringCache与Redis踩过的坑

1 场景回现

今天在做项目的时候需要使用SpringCache与Redis作为缓存
但是在，配置完成后，发现并没有达到目的

1.1 无法连接到远程的Redis

org.springframework.data.redis.RedisConnectionFailureException: Unable to 
connect to Redis;

1.2 无法实现缓存

在排查完无法连接到Redis之后，以为项目能够正常运行，结果发现前端无法访问到数据
后台直接报错

Bean named**is expected to be of type**but 
was actually of type ‘com.sun.proxy.$Proxy**

2 SpringBoot整合SpringCache与Redis步骤

整合步骤：

①导入依赖

<!-- redis -->
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-data-redis</artifactId>
</dependency>
<!-- spring2.X集成redis所需common-pool2-->
<dependency>
    <groupId>org.apache.commons</groupId>
    <artifactId>commons-pool2</artifactId>
    <version>2.6.0</version>
</dependency>

②application.properties配置文件

spring.redis.host=192.168.145.13
spring.redis.port=6379
spring.redis.database= 0
spring.redis.timeout=1800000
spring.redis.lettuce.pool.max-active=20
spring.redis.lettuce.pool.max-wait=-1
#最大阻塞等待时间(负数表示没限制)
spring.redis.lettuce.pool.max-idle=5
spring.redis.lettuce.pool.min-idle=0

③Redis配置类【自定义key规则、缓存规则、转换问题（序列化）】
RedisConfig:

/**
 * @author 夏末
 * @description TODO
 * @date 2022/10/1 10:11
 */
@Configuration
@EnableCaching
public class RedisConfig {
    /**
     * 自定义key规则
     * @return
     */
    @Bean
    public KeyGenerator keyGenerator() {
        return new KeyGenerator() {
            @Override
            public Object generate(Object target, Method method, Object... params) {
                StringBuilder sb = new StringBuilder();
                sb.append(target.getClass().getName());
                sb.append(method.getName());
                for (Object obj : params) {
                    sb.append(obj.toString());
                }
                return sb.toString();
            }
        };
    }
    /**
     * 设置RedisTemplate规则
     * @param redisConnectionFactory
     * @return
     */
    @Bean
    public RedisTemplate<Object, Object> redisTemplate(RedisConnectionFactory redisConnectionFactory) {
        RedisTemplate<Object, Object> redisTemplate = new RedisTemplate<>();
        redisTemplate.setConnectionFactory(redisConnectionFactory);
        Jackson2JsonRedisSerializer jackson2JsonRedisSerializer = new Jackson2JsonRedisSerializer(Object.class);
        //解决查询缓存转换异常的问题
        ObjectMapper om = new ObjectMapper();
        // 指定要序列化的域，field,get和set,以及修饰符范围，ANY是都有包括private和public
        om.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.ANY);
        // 指定序列化输入的类型，类必须是非final修饰的，final修饰的类，比如String,Integer等会跑出异常
        om.enableDefaultTyping(ObjectMapper.DefaultTyping.NON_FINAL);
        jackson2JsonRedisSerializer.setObjectMapper(om);
        //序列号key value
        redisTemplate.setKeySerializer(new StringRedisSerializer());
        redisTemplate.setValueSerializer(jackson2JsonRedisSerializer);
        redisTemplate.setHashKeySerializer(new StringRedisSerializer());
        redisTemplate.setHashValueSerializer(jackson2JsonRedisSerializer);
        redisTemplate.afterPropertiesSet();
        return redisTemplate;
    }
    /**
     * 设置CacheManager缓存规则
     * @param factory
     * @return
     */
    @Bean
    public CacheManager cacheManager(RedisConnectionFactory factory) {
        RedisSerializer<String> redisSerializer = new StringRedisSerializer();
        Jackson2JsonRedisSerializer jackson2JsonRedisSerializer = new Jackson2JsonRedisSerializer(Object.class);
        //解决查询缓存转换异常的问题
        ObjectMapper om = new ObjectMapper();
        om.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.ANY);
        om.enableDefaultTyping(ObjectMapper.DefaultTyping.NON_FINAL);
        jackson2JsonRedisSerializer.setObjectMapper(om);
        // 配置序列化（解决乱码的问题）,过期时间600秒
        RedisCacheConfiguration config = RedisCacheConfiguration.defaultCacheConfig()
                .entryTtl(Duration.ofSeconds(600))
                .serializeKeysWith(RedisSerializationContext.SerializationPair.fromSerializer(redisSerializer))
                .serializeValuesWith(RedisSerializationContext.SerializationPair.fromSerializer(jackson2JsonRedisSerializer))
                .disableCachingNullValues();
        RedisCacheManager cacheManager = RedisCacheManager.builder(factory)
                .cacheDefaults(config)
                .build();
        return cacheManager;
    }
}

④在service的对应实现类中添加相应注解

/**
     * 根据id查询子数据列表
     * @param id
     * @return
     */
    @Override
    @Cacheable(value = "dict",keyGenerator = "keyGenerator")
    public List<Dict> findChildData(Long id) {
        QueryWrapper<Dict> wrapper = new QueryWrapper<>();
        wrapper.eq("parent_id", id);
        List<Dict> dicts = dictMapper.selectList(wrapper);
        for(Dict dict : dicts){
            Long dictId = dict.getId();
            dict.setHasChildren(hasChild(dictId));
        }
        return dicts;
    }
/**
     * 导入数据
     * allEntries = true: 方法调用后清空所有缓存
     */
    @Override
    @CacheEvict(value = "dict", allEntries=true)
    public void importDictData(MultipartFile file) {
        try{
            EasyExcel.read(file.getInputStream(), DictEeVo.class, new DictListener(dictMapper))
                    .sheet().doRead();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

⑤在启动类上开启扫描（扫描RedisConfig配置类）

@SpringBootApplication
@EnableSwagger2
@ComponentScan(basePackages = {
    "com.zi"})
public class ServiceCmnApplication {
    public static void main(String[] args) {
        SpringApplication.run(ServiceCmnApplication.class);
    }
}

3 原因排查

3.1 无法连接到远程Redis

①配置文件端口配错
②远程Redis的保护模式打开了

"修改redis.conf文件"，将protected-mode配置设置为no

③bind绑定问题

"redis.conf文件"，bind设置为了只允许本机访问。
将该行注释，或者将项目运行的服务器地址配置上去

④设置了访问密码

"redis.conf文件"，在配置文件中将密码去掉或者在SpringBoot的application.yml中添加正确密码

3.2 无法实现缓存

①检查对应注解的value值是否正确
如：
Redis配置类的键生成器：
在这里插入图片描述
对应注解上的value值是否为类名首字母小写

②是否在配置类上开启注解，是否将配置类作为Bean交给Spring管理

@Configuration
@EnableCaching
public class RedisConfig {
    ...
}

③如果是多个模块的话，是否在启动类上添加了注解扫描

@SpringBootApplication
@EnableSwagger2
@ComponentScan(basePackages = {
    "com.zi"})
public class ServiceCmnApplication {
    public static void main(String[] args) {
        SpringApplication.run(ServiceCmnApplication.class);
    }
}