Springboot过滤器禁止ip频繁访问功能实现

在开发 Web 项目的时候，经常需要过滤器来处理一些请求，包括字符集转换什么的，记录请求日志什么的等等。在之前的 Web 开发中，我们习惯把过滤器配置到 web.xml 中，但是在 SpringBoot 中，兵没有这个配置文件，该如何操作呢？

1.编写一个过滤器：

import lombok.extern.slf4j.Slf4j;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.Iterator;
import java.util.Set;
import java.util.concurrent.ConcurrentHashMap;

@Slf4j
@WebFilter(urlPatterns="/dyflight/*")
public class IpFilter implements Filter{

  /**
   * 默认限制时间（单位：ms）3600000,3600(s),
   */
  private static final long LIMITED_TIME_MILLIS = 10 * 1000;

  /**
   * 用户连续访问最高阀值，超过该值则认定为恶意操作的IP，进行限制
   */
  private static final int LIMIT_NUMBER = 5;

  /**
   * 用户访问最小安全时间，在该时间内如果访问次数大于阀值，则记录为恶意IP，否则视为正常访问
   */
  private static final int MIN_SAFE_TIME = 5000;

  private FilterConfig config;

  @Override
  public void init(FilterConfig filterConfig) throws ServletException {
    this.config = filterConfig;  //设置属性filterConfig
  }

  /* (non-Javadoc)
   * @see javax.servlet.Filter#doFilter(javax.servlet.ServletRequest, javax.servlet.ServletResponse, javax.servlet.FilterChain)
   */
  @SuppressWarnings("unchecked")
  @Override
  public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain chain)
      throws IOException, ServletException {
    HttpServletRequest request = (HttpServletRequest) servletRequest;
    HttpServletResponse response = (HttpServletResponse) servletResponse;
    ServletContext context = config.getServletContext();
    // 获取限制IP存储器：存储被限制的IP信息
    //Map<String, Long> limitedIpMap = (Map<String, Long>) context.getAttribute("limitedIpMap");
    ConcurrentHashMap<String ,Long> limitedIpMap = (ConcurrentHashMap<String, Long>) context.getAttribute("limitedIpMap");
    // 过滤受限的IP
    filterLimitedIpMap(limitedIpMap);
    // 获取用户IP
    String ip = IPUtil.getRemoteIpAddr(request);
    System.err.println("ip:"+ip);
    // 判断是否是被限制的IP，如果是则跳到异常页面
    if (isLimitedIP(limitedIpMap, ip)) {
      long limitedTime = limitedIpMap.get(ip) - System.currentTimeMillis();
      // 剩余限制时间(用为从毫秒到秒转化的一定会存在些许误差，但基本可以忽略不计)
      request.setAttribute("remainingTime", ((limitedTime / 1000) + (limitedTime % 1000 > 0 ? 1 : 0)));
      System.err.println("ip访问过于频繁："+ip);
      throw new RuntimeException("ip访问过于频繁");
    }
    // 获取IP存储器
    ConcurrentHashMap<String, Long[]> ipMap = (ConcurrentHashMap<String, Long[]>) context.getAttribute("ipMap");
    // 判断存储器中是否存在当前IP，如果没有则为初次访问，初始化该ip
    // 如果存在当前ip，则验证当前ip的访问次数
    // 如果大于限制阀值，判断达到阀值的时间，如果不大于[用户访问最小安全时间]则视为恶意访问，跳转到异常页面
    if (ipMap.containsKey(ip)) {
      Long[] ipInfo = ipMap.get(ip);
      ipInfo[0] = ipInfo[0] + 1;
      log.debug("当前第[" + (ipInfo[0]) + "]次访问");
      if (ipInfo[0] > LIMIT_NUMBER) {
        Long ipAccessTime = ipInfo[1];
        Long currentTimeMillis = System.currentTimeMillis();

        log.debug("ip访问过于频繁：currentTimeMillis: "+currentTimeMillis+" - ipAccessTime:"+ipAccessTime+" : " + (currentTimeMillis - ipAccessTime) + "<="+ MIN_SAFE_TIME);

        if (currentTimeMillis - ipAccessTime <= MIN_SAFE_TIME) {
          limitedIpMap.put(ip, currentTimeMillis + LIMITED_TIME_MILLIS);
          request.setAttribute("remainingTime", LIMITED_TIME_MILLIS);

          log.debug("ip访问过于频繁：LIMITED_TIME_MILLIS:"+LIMITED_TIME_MILLIS);

          log.debug("ip访问过于频繁："+ip);
          throw new RuntimeException("ip访问过于频繁");
        } else {
          initIpVisitsNumber(ipMap, ip);
        }
      }
    } else {
      initIpVisitsNumber(ipMap, ip);
      System.out.println("您首次访问该网站");
    }
    context.setAttribute("ipMap", ipMap);
    chain.doFilter(request, response);
  }

  @Override
  public void destroy() {
    // TODO Auto-generated method stub
  }

  /**
   * @Description 过滤受限的IP，剔除已经到期的限制IP
   * @param limitedIpMap
   */
  private void filterLimitedIpMap(ConcurrentHashMap<String, Long> limitedIpMap) {
    if (limitedIpMap == null) {
      return;
    }
    Set<String> keys = limitedIpMap.keySet();
    Iterator<String> keyIt = keys.iterator();
    long currentTimeMillis = System.currentTimeMillis();
    while (keyIt.hasNext()) {
      long expireTimeMillis = limitedIpMap.get(keyIt.next());
      log.debug("expireTimeMillis <= currentTimeMillis:"+ expireTimeMillis+" <="+ currentTimeMillis);
      if (expireTimeMillis <= currentTimeMillis) {
        keyIt.remove();
      }
    }
  }

  /**
   * @Description 是否是被限制的IP
   * @param limitedIpMap
   * @param ip
   * @return true : 被限制 | false : 正常
   */
  private boolean isLimitedIP(ConcurrentHashMap<String, Long> limitedIpMap, String ip) {
    if (limitedIpMap == null || ip == null) {
      // 没有被限制
      return false;
    }
    Set<String> keys = limitedIpMap.keySet();
    Iterator<String> keyIt = keys.iterator();
    while (keyIt.hasNext()) {
      String key = keyIt.next();
      if (key.equals(ip)) {
        // 被限制的IP
        return true;
      }
    }
    return false;
  }

  /**
   * 初始化用户访问次数和访问时间
   *
   * @param ipMap
   * @param ip
   */
  private void initIpVisitsNumber(ConcurrentHashMap<String, Long[]> ipMap, String ip) {
    Long[] ipInfo = new Long[2];
    ipInfo[0] = 0L;// 访问次数
    ipInfo[1] = System.currentTimeMillis();// 初次访问时间
    ipMap.put(ip, ipInfo);
  }
}

2. 创建一个监听器：需要初始化俩个容器：

import lombok.extern.slf4j.Slf4j;

import javax.servlet.ServletContext;
import javax.servlet.ServletContextEvent;
import javax.servlet.ServletContextListener;
import javax.servlet.annotation.WebListener;
import java.util.concurrent.ConcurrentHashMap;

@Slf4j
@WebListener
public class MyApplicationListener implements ServletContextListener {

  @Override
  public void contextInitialized(ServletContextEvent sce) {
    log.debug("liting: contextInitialized");
    log.debug("MyApplicationListener初始化成功");
    ServletContext context = sce.getServletContext();
    // IP存储器
    ConcurrentHashMap<String, Long[]> ipMap = new ConcurrentHashMap<>();
    context.setAttribute("ipMap", ipMap);
    // 限制IP存储器：存储被限制的IP信息
    ConcurrentHashMap<String, Long> limitedIpMap = new ConcurrentHashMap<String, Long>();
    context.setAttribute("limitedIpMap", limitedIpMap);
    log.debug("ipmap："+ipMap.toString()+";limitedIpMap:"+limitedIpMap.toString()+"初始化成功。。。。。");
  }
  @Override
  public void contextDestroyed(ServletContextEvent sce) {
    // TODO Auto-generated method stub
  }
}

3.iputil

import javax.servlet.http.HttpServletRequest;
import java.net.InetAddress;
import java.net.UnknownHostException;

public class IPUtil {

  public static String getRemoteIpAddr(HttpServletRequest request) {
    String ip = request.getHeader("x-forwarded-for");
    if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
      ip = request.getHeader("Proxy-Client-IP");
    }
    if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
      ip = request.getHeader("WL-Proxy-Client-IP");
    }
    if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
      ip = request.getHeader("HTTP_CLIENT_IP");
    }
    if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
      ip = request.getHeader("HTTP_X_FORWARDED_FOR");
    }
    if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
      ip = request.getRemoteAddr();
      if("127.0.0.1".equals(ip)||"0:0:0:0:0:0:0:1".equals(ip)){
        //根据网卡取本机配置的IP
        InetAddress inet=null;
        try {
          inet = InetAddress.getLocalHost();
        } catch (UnknownHostException e) {
          e.printStackTrace();
        }
        ip= inet.getHostAddress();
      }
    }
    return ip;
  }

}

4配置

springboot启动类中添加过滤器和监听器的包扫描

@ServletComponentScan(basePackages="cn.xxx.common")

spring web.xml

过滤器

<filter>
    <filter-name>ipFilter</filter-name>
    <filter-class>com.xxxx.common.filter.IpFilter</filter-class>
  </filter>
  <filter-mapping>
    <filter-name>ipFilter</filter-name>
    <url-pattern>/dyflight/**</url-pattern>
  </filter-mapping>

监听器：

<listener>
    <listener-class>com.xxxx.common.Listener.MyApplicationListener</listener-class>
  </listener>

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持我们。

时间：2020-04-13