前言
项目地址:https://github.com/SunSmileAZY/anzy-master-v1
![Spring Cloud Hystrix 断路器容错保护快速入门](http://p2.ttnews.xyz/loading.gif)
用的模块:service-eruka、demo-cloud-01、demo-hystrix
一、新建一个Eureka Server服务
核心依赖包:
<code> <dependencies>
<dependency>
<groupid>org.springframework.cloud/<groupid>
<artifactid>spring-cloud-starter-netflix-eureka-server/<artifactid>
/<dependency>
/<dependencies>/<code>
启动类:
<code>package com.anzy.cloud.eruka;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.autoconfigure.amqp.RabbitAutoConfiguration;
import org.springframework.boot.autoconfigure.data.elasticsearch.ElasticsearchAutoConfiguration;
import org.springframework.boot.autoconfigure.data.mongo.MongoDataAutoConfiguration;
import org.springframework.boot.autoconfigure.data.redis.RedisAutoConfiguration;
import org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration;
import org.springframework.boot.autoconfigure.mongo.MongoAutoConfiguration;
import org.springframework.boot.autoconfigure.orm.jpa.HibernateJpaAutoConfiguration;
import org.springframework.cloud.netflix.eureka.server.EnableEurekaServer;
/**
* ServerEurekaApplication
*
* @author anzy
* @date 2018-05-01
*/
@SpringBootApplication(exclude = {
DataSourceAutoConfiguration.class,
HibernateJpaAutoConfiguration.class,
ElasticsearchAutoConfiguration.class,
RabbitAutoConfiguration.class,
RedisAutoConfiguration.class,
MongoAutoConfiguration.class,
MongoDataAutoConfiguration.class})
@EnableEurekaServer
public class ServerEurekaApplication {
public static void main(String[] args) {
SpringApplication.run(ServerEurekaApplication.class, args);
}
}/<code>
启动项目:
浏览器输入127.0.0.1:20000
![Spring Cloud Hystrix 断路器容错保护快速入门](http://p2.ttnews.xyz/loading.gif)
二、创建服务提供端demo-cloud-01
提供服务接口:
<code>package com.anzy.cloud.cloud01.product;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.cloud.client.ServiceInstance;
import org.springframework.cloud.client.discovery.DiscoveryClient;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.client.RestTemplate;
import java.util.List;
import java.util.Random;
/**
* @author anzy
* @version 1.0
* @date 2020/3/11 20:50
**/
@RestController
@RequestMapping(value = "/product")
public class ProductController {
@Autowired
RestTemplate restTemplate;
@Autowired
private DiscoveryClient discoveryClient;
@GetMapping("/list")
public String list(){
List<serviceinstance> serviceInstance = discoveryClient.getInstances("DEMO-CLOUD-01");
System.out.println(serviceInstance);
\t\t\t // 随机睡眠模拟超时,断路器默认2000ms
int sleepTime = new Random().nextInt(3000);
System.out.println("======== sleepTime: " + sleepTime);
try {
Thread.sleep(sleepTime);
} catch (InterruptedException e) {
e.printStackTrace();
}
return "成功调用demo-cloud-01 服务,我是商品列表";
}
}
/<serviceinstance>/<code>
三、创建服务调用者demo-hystrix
断路器需要引入spring-cloud-starter-netflix-hystrix包
<code>
<dependency>
<groupid>org.springframework.cloud/<groupid>
<artifactid>spring-cloud-starter-netflix-hystrix/<artifactid>
/<dependency>/<code>
开启断路器,在main类中开启@EnableCircuitBreaker
<code>import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.autoconfigure.amqp.RabbitAutoConfiguration;
import org.springframework.boot.autoconfigure.data.elasticsearch.ElasticsearchAutoConfiguration;
import org.springframework.boot.autoconfigure.data.mongo.MongoDataAutoConfiguration;
import org.springframework.boot.autoconfigure.data.redis.RedisAutoConfiguration;
import org.springframework.boot.autoconfigure.mongo.MongoAutoConfiguration;
import org.springframework.cloud.client.circuitbreaker.EnableCircuitBreaker;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
import org.springframework.cloud.client.loadbalancer.LoadBalanced;
import org.springframework.cloud.openfeign.EnableFeignClients;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.transaction.annotation.EnableTransactionManagement;
import org.springframework.web.client.RestTemplate;
/**
* ServerEurekaApplication
*
* @author anzy
* @date 2018-05-01
*/
@SpringBootApplication(exclude = {
ElasticsearchAutoConfiguration.class,
RabbitAutoConfiguration.class,
RedisAutoConfiguration.class,
MongoAutoConfiguration.class,
MongoDataAutoConfiguration.class})
@EnableTransactionManagement // 事务
//@EnableEurekaClient // @EnableEurekaClient只适用于Eureka作为注册中心,@EnableDiscoveryClient 可以是其他注册中心。
@EnableDiscoveryClient
@EnableCircuitBreaker
@EnableFeignClients(basePackages = {"com.anzy.cloud"})
@ComponentScan(basePackages = {"com.anzy.cloud"})
public class DemoHystrixApplication {
public static void main(String[] args) {
SpringApplication.run(DemoHystrixApplication.class, args);
}
@Bean
@LoadBalanced
RestTemplate restTemplate(){
return new RestTemplate();
}
}/<code>
<code>package com.anzy.cloud.hystrix.user;
import com.netflix.hystrix.contrib.javanica.annotation.HystrixCommand;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.client.RestTemplate;
/**
* 断路器使用
* @author anzy
* @version 1.0
* @date 2020/1/18 20:51
**/
@RestController
@RequestMapping(value = "/user")
public class UserController {
@Autowired
RestTemplate restTemplate;
@HystrixCommand(fallbackMethod = "productListFallback")
@GetMapping("/product/list")
public String productList(){
return restTemplate.getForEntity("http://DEMO-CLOUD-01/product/list",String.class).getBody().toString();
}
// 服务不可能或者超时调用此方法
public String productListFallback(){
return "DEMO-CLOUD-01 服务崩掉了";
}
}
/<code>
四、进行测试
打开postman调用 /user/product/list 接口
调用成功未超时
调用失败
具体代码可以看一下项目地址,直接运行service-eruka、demo-cloud-01、demo-hystrix三个项目即可,自己可以修改一下对应的配置。
本文主要是做一个断路器的入门认识一下hystrix,后面将会讲解具体的原理。
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