【汇智学堂】SpringCloud-Hystrix服务容错保护的调用

application.yml

server:
  port: 8030
spring:
  application:
    name: user-hystrix
eureka:
  instance:
    prefer-ip-address: true
  client:
    service-url:
      defualtZone: http://localhost:8761/eureka/

UserController:

package com.huizhi.userhystrix.controller;

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.PathVariable;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.client.RestTemplate;

@RestController
public class UserController {
    @Autowired
    private RestTemplate restTemplate;
    /**
     * 查找与用户相关的订单
     */
    @GetMapping("/findOrderByUser/{id}")
    @HystrixCommand(fallbackMethod = "fallbackInfo")
    public String findOrderByUser(@PathVariable String id){
        //假设用户只有一个订单，并且订单id为123
        int orderid=123;
        //直接使用IP
        //return this.restTemplate.getForObject("http://localhost:8763/order/"+orderid,String.class);
        //使用服务提供者的实例名称来执行已注册服务列表中实例的方法
        return this.restTemplate.getForObject("http://order/order/"+orderid,String.class);
     }
    /**
     * 返回信息方法,方法中的参数类型与原方法保持一致
     */
    public String fallbackInfo(@PathVariable String id){
        return "服务不可用，请稍后再试！";
    }
}

UserHystrixApplication:

package com.huizhi.userhystrix;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.circuitbreaker.EnableCircuitBreaker;
import org.springframework.cloud.client.loadbalancer.LoadBalanced;
import org.springframework.cloud.netflix.eureka.EnableEurekaClient;
import org.springframework.context.annotation.Bean;
import org.springframework.web.client.RestTemplate;

@SpringBootApplication
@EnableCircuitBreaker
@EnableEurekaClient
public class UserhystrixApplication {

    @Bean
    @LoadBalanced
    public RestTemplate restTemplate(){
        return new RestTemplate();
    }

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

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.2.2.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.huizhi</groupId>
    <artifactId>userhystrix</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>userhystrix</name>
    <description>Demo project for Spring Boot</description>

    <properties>
        <java.version>1.8</java.version>
        <spring-cloud.version>Hoxton.SR1</spring-cloud.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-hystrix</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
            <exclusions>
                <exclusion>
                    <groupId>org.junit.vintage</groupId>
                    <artifactId>junit-vintage-engine</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
    </dependencies>

    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>${spring-cloud.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

OrderController；

package com.huizhi.order2.controller;

import com.huizhi.order2.po.Order;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class OrderController {
    @GetMapping("/order/{id}")
    public String findOrderById(@PathVariable String id){
        Order order=new Order();
        order.setId("123");
        order.setPrice(25.5);
        order.setReceiverAddress("beijing");
        order.setReceiverName("xiaowang");
        order.setReceiverPhone("18900001234");
        System.out.println("8764");
        return order.toString();
    }
}

application.yml

server:
  port: 8764
spring:
  application:
    name: order
eureka:
  instance:
    prefer-ip-address: true
  client:
    service-url:
      defualtZone: http://localhost:8761/eureka/~

Order:

package com.huizhi.order2.po;

public class Order {

    private String id;
    private Double price;
    private String receiverName;
    private String receiverAddress;
    private String receiverPhone;

    public String getId() {
        return id;
    }

    public void setId(String id) {
        this.id = id;
    }

    public Double getPrice() {
        return price;
    }

    public void setPrice(Double price) {
        this.price = price;
    }

    public String getReceiverName() {
        return receiverName;
    }

    public void setReceiverName(String receiverName) {
        this.receiverName = receiverName;
    }

    public String getReceiverAddress() {
        return receiverAddress;
    }

    public void setReceiverAddress(String receiverAddress) {
        this.receiverAddress = receiverAddress;
    }

    public String getReceiverPhone() {
        return receiverPhone;
    }

    public void setReceiverPhone(String receiverPhone) {
        this.receiverPhone = receiverPhone;
    }

    @Override
    public String toString(){
        return "Order[id="+id+",price="+price+"," +
                "receiverName="+receiverName+"," +
                "receiverAddress="+receiverAddress+"," +
                "receiverPhone="+receiverPhone+"]";
    }
}