SpringCloud-Zuul的回退

最新推荐文章于 2024-10-30 14:19:18 发布

shenzhen_zsw

最新推荐文章于 2024-10-30 14:19:18 发布

阅读量406

点赞数

CC 4.0 BY-SA版权

分类专栏：【微服务/SpringCloud】

本文链接：https://blog.youkuaiyun.com/shenzhen_zsw/article/details/81009237

【微服务/SpringCloud】专栏收录该内容

233 篇文章

订阅专栏

概述

创建工程microservice-gateway-zuul-fallback

访问服务microservice-provider-user

将服务microservice-provider-user停掉

概述

在Spring Cloud, Zuul默认已经整合了Hystrix, 而且如果启动了Dashborad，也可以知道Zuul对Hystrix监控的粒度是微服务，而不是某一个API; 同时也说明所有经过Zuul的请求都会被Hystrix保护起来。

创建工程microservice-gateway-zuul-fallback

pom.xml

microservice-gateway-zuul-fallback/pom.xml

<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>

MyFallbackProvider

com.itmuch.cloud.fallback.MyFallbackProvider

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;

@Component
public class MyFallbackProvider implements ZuulFallbackProvider {
  @Override
  public String getRoute() {
    // 指定为哪一个微服务提供回退
    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;
      }
    };
  }
}

说明：

1）想要为Zuul添加回退，需要实现ZuulFallbackProvider接口。

2）在实现类中，指定为哪一个微服务提供回退，并且提供一个ClientHttpResponse作为回退响应。

application.yml

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

ZuulApplication

com.itmuch.cloud.ZuulApplication

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);
  }
}