25 zuul权限校验、接口限流

1，权限校验:


package com.taotao.steam.gateway.filter;

import com.netflix.zuul.ZuulFilter;
import com.netflix.zuul.context.RequestContext;
import com.netflix.zuul.exception.ZuulException;
import lombok.extern.slf4j.Slf4j;
import org.apache.logging.log4j.util.Strings;
import org.springframework.cloud.netflix.zuul.filters.support.FilterConstants;
import org.springframework.stereotype.Component;

import javax.servlet.http.HttpServletRequest;
/**
 * @author aping
 * @time 2020/5/3 11:28
 */
@Component
@Slf4j
public class TokenFilter  extends ZuulFilter {
    /**
     * 过滤类型 pre 表示在请求之前进行执行
     * @return
     */
    @Override
    public String filterType() {
        return "pre";
    }

    /**
     * 过滤器执行顺序 ，当一个请求在同一阶段的时候存在多个过滤器的时候，多个过滤器执行顺序
     * @return
     */
    @Override
    public int filterOrder() {
        return 0;
    }

    @Override
    public boolean shouldFilter() {
        //共享RequestContext，上下文对象
        RequestContext requestContext = RequestContext.getCurrentContext();
        HttpServletRequest request = requestContext.getRequest();

        System.out.println(request.getRequestURI());
        //需要权限校验URL
        if ("/swagger-ui.html/**".equalsIgnoreCase(request.getRequestURI())) {
            return true;
        } else if ("/api-aop/**".equalsIgnoreCase(request.getRequestURI())) {
            return true;
        }else if ("/api-backstage/**".equalsIgnoreCase(request.getRequestURI())) {
            return true;
        }else if ("/api-community/**".equalsIgnoreCase(request.getRequestURI())) {
            return true;
        }
        return  false;


    }

    /**
     * 编写业务逻辑代码
     * @return
     * @throws ZuulException
     */
    @Override
    public Object run() throws ZuulException {


        //获取所有的服务接口，判断服务是否有传递token
        //1获取上下文
        RequestContext currentcontext= RequestContext.getCurrentContext();
        //获取request
        HttpServletRequest request=currentcontext.getRequest();
        String token=request.getParameter("userToken");
        if(Strings.isBlank(token)){
            currentcontext.setSendZuulResponse(false);
            currentcontext.setResponseBody("token is null");
            currentcontext.setResponseStatusCode(401);
        }
        log.info("通过过滤");
        return null;

    }
}

2,接口限流：
集成guava

<!-- https://mvnrepository.com/artifact/com.google.guava/guava -->
<dependency>
    <groupId>com.google.guava</groupId>
    <artifactId>guava</artifactId>
    <version>29.0-jre</version>
</dependency>

接口限流可以在nginx层面做限流，也可以在网关层面做限流，这里在网关层面做限流，基于guava框架来做网关限流。

先对guava框架限流的概念进行讲解下：

1090617-20180906213610239-526459252.png

的大致意思就是每一个请求进来先到桶里去拿令牌，拿到令牌的请求放行，假设你设置了1000个令牌，如果拿完了，那么后面来调接口的请求就需要排队等有新的令牌才能调用该接口。


package com.taotao.steam.gateway.filter;

import com.google.common.util.concurrent.RateLimiter;
import com.netflix.zuul.ZuulFilter;
import com.netflix.zuul.context.RequestContext;
import com.netflix.zuul.exception.ZuulException;
import org.springframework.http.HttpStatus;
import org.springframework.stereotype.Component;

import javax.servlet.http.HttpServletRequest;

/**
* 接口限流
* @author aping
* @time 2020/5/3 16:02
*/
@Component
public class OrderRateLimiterFilter extends ZuulFilter {
  //每秒差生1000个令牌
  private  static  final RateLimiter RATE_LIMITER=RateLimiter.create(1);

  @Override
  public String filterType() {
      return "pre";
  }

  @Override
  public int filterOrder() {
      return 0;
  }

  @Override
  public boolean shouldFilter() {
      RequestContext requestContext=RequestContext.getCurrentContext();
      HttpServletRequest request =requestContext.getRequest();
      //只对特定接口限流
      if("/api-aop/**".equals(request.getRequestURI())){
          return  true;
      }

      return false;
  }

  @Override
  public Object run() throws ZuulException {
      RequestContext requestContext=RequestContext.getCurrentContext();
      //相当于每调用一次tryAcquire()方法。令牌数量减去1，当1000个令牌用完后，后面的接口不能访问呢进来
      //当然这里只写类上面一个接口，可以这么写，实际可以在这里要加一层接口判断。
      if(!RATE_LIMITER.tryAcquire()){
          requestContext.setSendZuulResponse(false);
          //HttpStatus.TOO_MANY_REQUESTS.value()
          requestContext.setResponseStatusCode(HttpStatus.TOO_MANY_REQUESTS.value());
      }
      return null;
  }
}