API服务网关（Zuul）

zuul:
  SendResponseFilter:
    post:
      disable: true

public class MyFilter extends ZuulFilter {
    @Override
    String filterType() {
        return "pre"; // 定义filter的类型，有pre、route、post、error四种
    }

    @Override
    int filterOrder() {
        return 5; // 定义filter的顺序，数字越小表示顺序越高，越先执行
    }

    @Override
    boolean shouldFilter() {
        return true; // 表示是否需要执行该filter，true表示执行，false表示不执行
    }

    @Override
    Object run() {
        return null; // filter需要执行的具体操作
    }
}

4.0.0org.springframework.boot
        spring-boot-starter-parent
        2.0.4.RELEASEcom.louis
    spring-cloud-consul-zuul
    ${project.version}jarspring-cloud-consul-zuulspring-cloud-consul-zuulUTF-8UTF-81.0.01.8Finchley.RELEASEorg.springframework.cloud
            spring-cloud-starter-netflix-zuul
        org.springframework.cloud
            spring-cloud-starter-consul-discovery
        org.springframework.cloud
                spring-cloud-dependencies
                ${spring-cloud.version}pomimportorg.springframework.boot
                spring-boot-maven-plugin
            

package com.louis.spring.cloud.consul.zuul;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.zuul.EnableZuulProxy;

@EnableZuulProxy
@SpringBootApplication
public class ZuulApplication {

    public static void main(String[] args) {
        SpringApplication.run(ZuulApplication.class, args);
    }
}

server:
  port: 8541
spring:
  application:
    name: spring-cloud-consul-zuul
  cloud:
    consul:
      host: localhost
      port: 8500
      discovery:
        serviceName: ${spring.application.name}    # 注册到consul的服务名称
zuul:
  routes:
    ribbon:
      path: /ribbon/**
      serviceId: spring-cloud-consul-consumer  # 转发到消费者 /ribbon/
    feign:
      path: /feign/**
      serviceId: spring-cloud-consul-consumer  # 转发到消费者 /feign/

zuul:
  prefix: /v1
  routes:
    ribbon:
      path: /ribbon/**
      serviceId: spring-cloud-consul-consumer  # 转发到消费者 /ribbon/
    feign:
      path: /feign/**
      serviceId: spring-cloud-consul-consumer  # 转发到消费者 /feign/

zuul:
  routes:
    ribbon:
      path: /ribbon/**
      serviceId: spring-cloud-consul-consumer  # 转发到消费者 /ribbon/
    feign:
      path: /feign/**
      serviceId: spring-cloud-consul-consumer  # 转发到消费者 /feign/

package com.louis.spring.cloud.consul.zuul;

import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;

import org.springframework.cloud.netflix.zuul.filters.route.FallbackProvider;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpStatus;
import org.springframework.http.MediaType;
import org.springframework.http.client.ClientHttpResponse;
import org.springframework.stereotype.Component;

@Component
public class MyFallbackProvider implements FallbackProvider {
    @Override
    public String getRoute() {
        return "spring-cloud-consul-consumer";
    }

    @Override
    public ClientHttpResponse fallbackResponse(String route, Throwable cause) {
        System.out.println("route:"+route);
        System.out.println("exception:"+cause.getMessage());
        return new ClientHttpResponse() {
            @Override
            public HttpStatus getStatusCode() throws IOException {
                return HttpStatus.OK;
            }

            @Override
            public int getRawStatusCode() throws IOException {
                return 200;
            }

            @Override
            public String getStatusText() throws IOException {
                return "ok";
            }

            @Override
            public void close() {

            }

            @Override
            public InputStream getBody() throws IOException {
                return new ByteArrayInputStream("Sorry, the service is unavailable now.".getBytes());
            }

            @Override
            public HttpHeaders getHeaders() {
                HttpHeaders headers = new HttpHeaders();
                headers.setContentType(MediaType.APPLICATION_JSON);
                return headers;
            }
        };
    }
}

package com.louis.spring.cloud.consul.zuul;

import java.io.IOException;

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;
import com.netflix.zuul.exception.ZuulException;

@Component
public class MyFilter extends ZuulFilter {

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

    @Override
    public String filterType() {
        return "pre"; // 定义filter的类型，有pre、route、post、error四种
    }

    @Override
    public int filterOrder() {
        return 0; // 定义filter的顺序，数字越小表示顺序越高，越先执行
    }

    @Override
    public boolean shouldFilter() {
        return true; // 表示是否需要执行该filter，true表示执行，false表示不执行
    }

    @Override
    public Object run() throws ZuulException {
        // filter需要执行的具体操作
        RequestContext ctx = RequestContext.getCurrentContext();
        HttpServletRequest request = ctx.getRequest();
        String token = request.getParameter("token");
        System.out.println(token);
        if(token==null){
            log.warn("there is no request token");
            ctx.setSendZuulResponse(false);
            ctx.setResponseStatusCode(401);
            try {
                ctx.getResponse().getWriter().write("there is no request token");
            } catch (IOException e) {
                e.printStackTrace();
            }
            return null;
        }
        log.info("ok");
        return null;
    }
}