SpringCloud-----zuul网关过滤

版权声明：本文为博主原创文章，未经博主允许不得转载。 https://blog.csdn.net/zhangminemail/article/details/83585320

1、概念

什么是网关

Zuul的主要功能是路由转发和过滤器。路由功能是微服务的一部分，比如／api/user转发到到user服务，/api/shop转发到到shop服务。zuul默认和Ribbon结合实现了负载均衡的功能， 类似于nginx转发。

2、继承ZuulFilter，重写run接口

package com.cloud.zuul;

import javax.servlet.http.HttpServletRequest;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Component;

import com.netflix.zuul.ZuulFilter;
import com.netflix.zuul.context.RequestContext;

@Component
public class MyFilter extends ZuulFilter {

	private static Logger log = LoggerFactory.getLogger(MyFilter.class);

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

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

	public boolean shouldFilter() {
		return true;
	}

	public Object run() {
		RequestContext ctx = RequestContext.getCurrentContext();
		HttpServletRequest request = ctx.getRequest();
		log.info(String.format("%s >>> %s", request.getMethod(), request.getRequestURL().toString()));
		Object accessToken = request.getParameter("token");
		if (accessToken != null) {
			return null;
		}
		log.warn("token is empty");
		ctx.setSendZuulResponse(false);
		ctx.setResponseStatusCode(401);
		try {
			ctx.getResponse().getWriter().write("token is empty");
		} catch (Exception e) {
		}
		return null;

	}


}