Zuul自定义过滤器及熔断配置

2.2.2.RELEASEspring-cloud-netflix-zuul-2.2.2.RELEASE.jar!orgspringframeworkcloud etflixzuulfilterssupportFilterConstants.class

    public static final String ERROR_TYPE = "error";
    public static final String POST_TYPE = "post";
    public static final String PRE_TYPE = "pre";
    public static final String ROUTE_TYPE = "route";

Zuul过滤器有四种类型，pre前置和post后置都是相对于routing路由调用远程服务而言的，这三种过滤器不论哪一个出现异常都会到error过滤器，自定义过滤器可以是这四种过滤器之一

例子为前置过滤器

package com.company.filter;

import com.netflix.zuul.ZuulFilter;
import com.netflix.zuul.context.RequestContext;
import com.netflix.zuul.exception.ZuulException;
import org.apache.commons.lang.StringUtils;
import org.springframework.cloud.netflix.zuul.filters.support.FilterConstants;
import org.springframework.http.HttpStatus;
import org.springframework.stereotype.Component;

import javax.servlet.http.HttpServletRequest;

//必须注入sping容器，否则无效
@Component
public class LoginFilter extends ZuulFilter{
    @Override
    public String filterType() {
        //指定过滤器类型
        return FilterConstants.PRE_TYPE;
    }

    @Override
    public int filterOrder() {
        //指定优先级，越小优先级越高
        return FilterConstants.PRE_DECORATION_FILTER_ORDER-1;
    }

    @Override
    public boolean shouldFilter() {
        //是否启用过滤
        return true;
    }

    @Override
    public Object run() throws ZuulException {
        //过滤逻辑
        //获取Zuul中的request上下文对象
        RequestContext ctx = RequestContext.getCurrentContext();
        //获取request对象
        HttpServletRequest request = ctx.getRequest();
        //简单demo，判断是否带有token参数
        String token = request.getParameter("token");
        if(StringUtils.isBlank(token)){
            //setSendZuulResponse方法传入false表示拦截，默认true放行。
            ctx.setSendZuulResponse(false);
            //响应403状态码
            ctx.setResponseStatusCode(HttpStatus.FORBIDDEN.value());
        }
        return null;
    }
}

 熔断配置

　Ribbon超时计算公式：（连接时长+读取时长）*(当前实例重试次数+1)*(切换实例重试次数+1)

zuul:
  retryable: true
ribbon:
  ConnectTimeout: 250 # 连接超时时间(ms)[默认1秒]
  ReadTimeout: 2000 # 通信超时时间(ms)[默认1秒]
  OkToRetryOnAllOperations: true # 是否对所有操作重试
  MaxAutoRetriesNextServer: 1 # 同一服务不同实例的重试次数[默认是1次]
  MaxAutoRetries: 0 # 同一实例的重试次数[默认是0次]
hystrix:
  command:
   default:
        execution:
          isolation:
            thread:
              timeoutInMillisecond: 6000 # 熔断超时时长：6000ms[默认是1秒]