package com.itmuch.cloud;

import org.springframework.boot.SpringApplication;

import org.springframework.boot.autoconfigure.SpringBootApplication;

import org.springframework.cloud.netflix.zuul.EnableZuulProxy;

@SpringBootApplication

@EnableZuulProxy

public class ZuulApplication {

  public static void main(String[] args) {

    SpringApplication.run(ZuulApplication.class, args);

  }

}

package com.itmuch.cloud.fallback;

import java.io.ByteArrayInputStream;

import java.io.IOException;

import java.io.InputStream;

import org.springframework.cloud.netflix.zuul.filters.route.ZuulFallbackProvider;

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;

//通过zuul（8040端口）访问user微服务http://localhost:8040/microservice-provider-user/simple/1

//如果此时user微服务停掉，就会返回"fallbackmicroservice-provider-user",(使用的是hysitrcs的断路器功能)

//feign的Fallback是针对一个类，zuul的Fallback是针对一个微服务。

@Component

public class MyFallbackProvider implements ZuulFallbackProvider {

  @Override

  public String getRoute() {

    return "microservice-provider-user";

  }

  @Override

  public ClientHttpResponse fallbackResponse() {

    return new ClientHttpResponse() {

      @Override

      public HttpStatus getStatusCode() throws IOException {

        return HttpStatus.BAD_REQUEST;

      }

      @Override

      public int getRawStatusCode() throws IOException {

        return HttpStatus.BAD_REQUEST.value();

      }

      @Override

      public String getStatusText() throws IOException {

        return HttpStatus.BAD_REQUEST.getReasonPhrase();

      }

      @Override

      public void close() {

      }

      @Override

      public InputStream getBody() throws IOException {

        return new ByteArrayInputStream(("fallback" + MyFallbackProvider.this.getRoute()).getBytes());

      }

      @Override

      public HttpHeaders getHeaders() {

        HttpHeaders headers = new HttpHeaders();

        headers.setContentType(MediaType.APPLICATION_JSON);

        return headers;

      }

    };

  }

}

spring:

  application:

    name: microservice-gateway-zuul

server:

  port: 8040

eureka:

  client:

    service-url:

      defaultZone: http://user:password123@localhost:8761/eureka

  instance:

    prefer-ip-address: true

hystrix.command.default.execution.isolation.thread.timeoutInMilliseconds: 60000

ribbon:

  ConnectTimeout: 3000

  ReadTimeout: 60000

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">

    <modelVersion>4.0.0</modelVersion>

    <parent>

        <groupId>com.itmuch.cloud</groupId>

        <artifactId>microservice-spring-cloud</artifactId>

        <version>0.0.1-SNAPSHOT</version>

    </parent>

    <artifactId>microservice-gateway-zuul-fallback</artifactId>

    <packaging>jar</packaging>

    <properties>

        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>

    </properties>

    <dependencies>

        <dependency>

            <groupId>org.springframework.cloud</groupId>

            <artifactId>spring-cloud-starter-zuul</artifactId>

        </dependency>

        <dependency>

            <groupId>org.springframework.cloud</groupId>

            <artifactId>spring-cloud-starter-eureka</artifactId>

        </dependency>

    </dependencies>

</project>