/**
 * @package: com.technicalinterest.group.interceptor
 * @className: IpUrlLimitInterceptor
 * @description: ip+url重復(fù)請(qǐng)求現(xiàn)在攔截器
 * @author: Shuyu.Wang
 * @date: 2019-10-12 12:34
 * @since: 0.1
 **/
@Slf4j
public class IpUrlLimitInterceptor implements HandlerInterceptor {
 
 
    private RedisUtil getRedisUtil() {
        return  SpringContextUtil.getBean(RedisUtil.class);
    }
 
    private static final String LOCK_IP_URL_KEY="lock_ip_";
 
    private static final String IP_URL_REQ_TIME="ip_url_times_";
 
    private static final long LIMIT_TIMES=5;
 
    private static final int IP_LOCK_TIME=60;
 
    @Override
    public boolean preHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o) throws Exception {
        log.info("request請(qǐng)求地址uri={},ip={}", httpServletRequest.getRequestURI(), IpAdrressUtil.getIpAdrress(httpServletRequest));
        if (ipIsLock(IpAdrressUtil.getIpAdrress(httpServletRequest))){
            log.info("ip訪問(wèn)被禁止={}",IpAdrressUtil.getIpAdrress(httpServletRequest));
            ApiResult result = new ApiResult(ResultEnum.LOCK_IP);
            returnJson(httpServletResponse, JSON.toJSONString(result));
            return false;
        }
        if(!addRequestTime(IpAdrressUtil.getIpAdrress(httpServletRequest),httpServletRequest.getRequestURI())){
            ApiResult result = new ApiResult(ResultEnum.LOCK_IP);
            returnJson(httpServletResponse, JSON.toJSONString(result));
            return false;
        }
        return true;
    }
 
    @Override
    public void postHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, ModelAndView modelAndView) throws Exception {
 
    }
 
    @Override
    public void afterCompletion(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, Exception e) throws Exception {
 
    }
 
    /**
     * @Description: 判斷ip是否被禁用
     * @author: shuyu.wang
     * @date: 2019-10-12 13:08
     * @param ip
     * @return java.lang.Boolean
     */
    private Boolean ipIsLock(String ip){
        RedisUtil redisUtil=getRedisUtil();
        if(redisUtil.hasKey(LOCK_IP_URL_KEY+ip)){
            return true;
        }
        return false;
    }
    /**
     * @Description: 記錄請(qǐng)求次數(shù)
     * @author: shuyu.wang
     * @date: 2019-10-12 17:18
     * @param ip
     * @param uri
     * @return java.lang.Boolean
     */
    private Boolean addRequestTime(String ip,String uri){
        String key=IP_URL_REQ_TIME+ip+uri;
        RedisUtil redisUtil=getRedisUtil();
        if (redisUtil.hasKey(key)){
            long time=redisUtil.incr(key,(long)1);
            if (time>=LIMIT_TIMES){
                redisUtil.getLock(LOCK_IP_URL_KEY+ip,ip,IP_LOCK_TIME);
                return false;
            }
        }else {
            redisUtil.getLock(key,(long)1,1);
        }
        return true;
    }
 
    private void returnJson(HttpServletResponse response, String json) throws Exception {
        PrintWriter writer = null;
        response.setCharacterEncoding("UTF-8");
        response.setContentType("text/json; charset=utf-8");
        try {
            writer = response.getWriter();
            writer.print(json);
        } catch (IOException e) {
            log.error("LoginInterceptor response error ---> {}", e.getMessage(), e);
        } finally {
            if (writer != null) {
                writer.close();
            }
        }
    }
 
 
}

/**
?* @package: com.shuyu.blog.util
?* @className: RedisUtil
?* @description:
?* @author: Shuyu.Wang
?* @date: 2019-07-14 14:42
?* @since: 0.1
?**/
@Component
@Slf4j
public class RedisUtil {
?
?? ?private static final Long SUCCESS = 1L;
?
?? ?@Autowired
?? ?private RedisTemplate<String, Object> redisTemplate;
?? ?// =============================common============================
?
?? ?
?
?? ?/**
?? ? * 獲取鎖
?? ? * @param lockKey
?? ? * @param value
?? ? * @param expireTime：?jiǎn)挝?秒
?? ? * @return
?? ? */
?? ?public boolean getLock(String lockKey, Object value, int expireTime) {
?? ??? ?try {
?? ??? ??? ?log.info("添加分布式鎖key={},expireTime={}",lockKey,expireTime);
?? ??? ??? ?String script = "if redis.call('setNx',KEYS[1],ARGV[1]) then if redis.call('get',KEYS[1])==ARGV[1] then return redis.call('expire',KEYS[1],ARGV[2]) else return 0 end end";
?? ??? ??? ?RedisScript<String> redisScript = new DefaultRedisScript<>(script, String.class);
?? ??? ??? ?Object result = redisTemplate.execute(redisScript, Collections.singletonList(lockKey), value, expireTime);
?? ??? ??? ?if (SUCCESS.equals(result)) {
?? ??? ??? ??? ?return true;
?? ??? ??? ?}
?? ??? ?} catch (Exception e) {
?? ??? ??? ?e.printStackTrace();
?? ??? ?}
?? ??? ?return false;
?? ?}
?
?? ?/**
?? ? * 釋放鎖
?? ? * @param lockKey
?? ? * @param value
?? ? * @return
?? ? */
?? ?public boolean releaseLock(String lockKey, String value) {
?? ??? ?String script = "if redis.call('get', KEYS[1]) == ARGV[1] then return redis.call('del', KEYS[1]) else return 0 end";
?? ??? ?RedisScript<String> redisScript = new DefaultRedisScript<>(script, String.class);
?? ??? ?Object result = redisTemplate.execute(redisScript, Collections.singletonList(lockKey), value);
?? ??? ?if (SUCCESS.equals(result)) {
?? ??? ??? ?return true;
?? ??? ?}
?? ??? ?return false;
?? ?}
?
}

@Configuration
@Slf4j
public class MyWebAppConfig extends WebMvcConfigurerAdapter {
    @Bean
    IpUrlLimitInterceptor getIpUrlLimitInterceptor(){
        return new IpUrlLimitInterceptor();
    }
 
 @Override
    public void addInterceptors(InterceptorRegistry registry) {
        registry.addInterceptor(getIpUrlLimitInterceptor()).addPathPatterns("/**");
        super.addInterceptors(registry);
    }
}