springboot 自定义拦截器 防止恶意请求

该例子需要用到 redis 

在applocation.properties中加入redis的配置信息

server.port=8030

# Redis数据库索引（默认为0）
spring.redis.database=0 
# Redis服务器地址
spring.redis.host=localhost
# Redis服务器连接端口
spring.redis.port=6379 
# Redis服务器连接密码（默认为空）
spring.redis.password=
#连接池最大连接数（使用负值表示没有限制）
spring.redis.jedis.pool.max-idle=8 
# 连接池最大阻塞等待时间（使用负值表示没有限制）
spring.redis.jedis.pool.max-wait=
# 连接池中的最大空闲连接
spring.redis.jedis..pool.max-idle=8 
# 连接池中的最小空闲连接
spring.redis.jedis.pool.min-idle=0 
# 连接超时时间（毫秒）
spring.redis.timeout=300

RedisConfig.java

package cn.rc.config;

import org.springframework.cache.annotation.CachingConfigurerSupport;
import org.springframework.cache.annotation.EnableCaching;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.redis.connection.RedisConnectionFactory;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.data.redis.serializer.Jackson2JsonRedisSerializer;
import org.springframework.data.redis.serializer.StringRedisSerializer;

import com.fasterxml.jackson.annotation.JsonAutoDetect;
import com.fasterxml.jackson.annotation.PropertyAccessor;
import com.fasterxml.jackson.databind.ObjectMapper;

@Configuration
@EnableCaching // 开启注解
public class RedisConfig extends CachingConfigurerSupport {

    @Bean
    public RedisTemplate<String, Object> redisTemplate(RedisConnectionFactory factory) {

        RedisTemplate<String, Object> template = new RedisTemplate<>();
        // 配置连接工厂
        template.setConnectionFactory(factory);

        // 使用Jackson2JsonRedisSerializer来序列化和反序列化redis的value值（默认使用JDK的序列化方式）
        Jackson2JsonRedisSerializer jacksonSeial = new Jackson2JsonRedisSerializer(Object.class);

        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);
        jacksonSeial.setObjectMapper(om);

        // 值采用json序列化
        template.setValueSerializer(jacksonSeial);
        // 使用StringRedisSerializer来序列化和反序列化redis的key值
        template.setKeySerializer(new StringRedisSerializer());

        // 设置hash key 和value序列化模式
        template.setHashKeySerializer(new StringRedisSerializer());
        template.setHashValueSerializer(jacksonSeial);
        template.afterPropertiesSet();

        return template;
    }
}

需要先启动redis功能

一、声明一个自定义的注解类

AccessLimit.java

@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.METHOD)
public @interface AccessLimit {
    int seconds();
    int maxCount();
    boolean needLogin() default true;
}

二、声明一个自定义的拦截器：

AccessLimtInterceptor.java 

@Component
public class AccessLimtInterceptor implements HandlerInterceptor {

    @Autowired
    private RedisTemplate redisTemplate;

    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {

        if (handler instanceof HandlerMethod) {
            HandlerMethod hm = (HandlerMethod) handler;
            AccessLimit accessLimit = hm.getMethodAnnotation(AccessLimit.class);
            if (null == accessLimit) {
                return true;
            }
            int seconds = accessLimit.seconds();
            int maxCount = accessLimit.maxCount();
            boolean needLogin = accessLimit.needLogin();

            if (needLogin) {
                //判断是否登录
            }
            String ip=request.getRemoteAddr();
            String key = request.getServletPath() + ":" + ip ;
            Integer count = (Integer) redisTemplate.opsForValue().get(key);

            if (null == count || -1 == count) {
                redisTemplate.opsForValue().set(key, 1,seconds, TimeUnit.SECONDS);
                return true;
            }

            if (count < maxCount) {
                count = count+1;
                redisTemplate.opsForValue().set(key, count,0);
                return true;
            }

            if (count >= maxCount) {
//                response 返回 json 请求过于频繁请稍后再试
                response.setCharacterEncoding("UTF-8");
                response.setContentType("application/json; charset=utf-8");
                JsonResponse  result = new JsonResponse<>();
                result.setCode(9999);
                result.setMessage("操作过于频繁");
                Object obj = JSONObject.toJSON(result);
                response.getWriter().write(JSONObject.toJSONString(obj));
                return false;
            }
        }

        return true;
    }
}

将 拦截器 注册到容器：WebMvcConfig.java

/**
 * MVC 设置
 *
 */
@Configuration
public class WebMvcConfig extends WebMvcConfigurerAdapter {
    @Autowired
    private AccessLimtInterceptor accessLimtInterceptor;
    @Bean
    public AccessTokenVerifyInterceptor tokenVerifyInterceptor() {
        return new AccessTokenVerifyInterceptor();
    }

    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        registry.addInterceptor(accessLimtInterceptor);
        registry.addInterceptor(tokenVerifyInterceptor()).addPathPatterns("/**");
        super.addInterceptors(registry);
    }

}

进行测试接口:

使用 @AccessLimit(seconds = 15, maxCount = 3)  注解 修饰接口 , 15秒 只允许访问3次

@RestController
@RequestMapping("test")
public class TestAccessLimitController {

    @GetMapping("accessLimit")
    @AccessLimit(seconds = 15, maxCount = 3) //15秒内 允许请求3次
    public String testAccessLimit() {

        return "success";
    }
}

浏览器请求：http://localhost:8030/test/accessLimit

　　返回: success 

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