springcloud hystrix 容错机制-爱代码爱编程

1.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>
        <artifactId>springcloudDemo</artifactId>
        <groupId>org.example</groupId>
        <version>1.0-SNAPSHOT</version>
    </parent>

    <groupId>com.weitao</groupId>
    <artifactId>springcloud-hystrix</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>springcloud-hystrix</name>
    <description>Demo project for Spring Boot</description>
    <properties>
        <java.version>1.8</java.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-openfeign</artifactId>
            <version>2.2.6.RELEASE</version>
        </dependency>

        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
            <version>2.2.6.RELEASE</version>
        </dependency>

        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-hystrix</artifactId>
            <version>2.2.6.RELEASE</version>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
            <version>2.2.6.RELEASE</version>
        </dependency>

        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-hystrix-dashboard</artifactId>
            <version>2.2.6.RELEASE</version>
        </dependency>

        <dependency>
            <groupId>org.example</groupId>
            <artifactId>springcloud-api</artifactId>
            <version>1.0-SNAPSHOT</version>
        </dependency>


    </dependencies>


    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>
    <repositories>
        <repository>
            <id>spring-snapshots</id>
            <name>Spring Snapshots</name>
            <url>https://repo.spring.io/snapshot</url>
            <releases>
                <enabled>false</enabled>
            </releases>
        </repository>
        <repository>
            <id>spring-milestones</id>
            <name>Spring Milestones</name>
            <url>https://repo.spring.io/milestone</url>
            <snapshots>
                <enabled>false</enabled>
            </snapshots>
        </repository>
    </repositories>

</project>

2.application.yml

server:
  port: 8060
spring:
  application:
    name: hystrix
eureka:
  client:
    service-url:
      defaultZone: http://localhost:8761/eureka/
  instance:
    prefer-ip-address: true
    instance-id: ${spring.application.name}:${server.port}
#断路器，起到降级作用，避免服务雪崩
feign:
  hystrix:
    enabled: true

management:
  endpoints:
    web:
      exposure:
        include: 'hystrix.stream'
hystrix:
  dashboard:
    proxy-stream-allow-list: localhost

3.代码结构

4.具体代码

package com.example.springcloud.controller;

import com.example.springcloud.fegin.FeginDept;
import com.example.springcloud.pojo.Dept;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;

import java.util.List;

@RestController
@RequestMapping("/hystrix")
public class HystrixController {

    @Autowired
    private FeginDept feginDept;

    @GetMapping("/select")
    public List<Dept> get() {
        return feginDept.selectAll();
    }

    @GetMapping("/select/{id}")
    public Dept selectByID(@PathVariable(name = "id") Long id) {
        return feginDept.selectByID(id);
    }

    @PostMapping(value = "/save", produces = "application/json")
    public boolean saveDept(@RequestBody Dept dept) {
        return feginDept.saveDept(dept);
    }

    //假如服务提供者没启动,直接访问/handle/getInfo 那么容错机制就会调用FeginDept  fallback属性设置FeginError 里的方法
    @GetMapping("/getInfo")
    public String getInfo() {
        return feginDept.getInfo();
    }
}

package com.example.springcloud.fegin;

import com.example.springcloud.pojo.Dept;
import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestBody;

import java.util.List;

/**
 * 接口注解方式
 * value="provider" 调用提供者的应用名称
 */
@FeignClient(value = "provider")
public interface FeginDept {

    @PostMapping(value = "/dept/save",produces = "application/json")
    boolean saveDept(@RequestBody  Dept dept);


    @GetMapping("/dept/select/{id}")
    Dept selectByID(@PathVariable("id") Long id);

    @GetMapping("/dept/select")
    List<Dept> selectAll();


    @GetMapping("/dept/getInfo")
    String getInfo();

}

package com.example.springcloud;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.hystrix.EnableHystrix;
import org.springframework.cloud.netflix.hystrix.dashboard.EnableHystrixDashboard;
import org.springframework.cloud.openfeign.EnableFeignClients;

@SpringBootApplication
@EnableFeignClients
@EnableHystrix
@EnableHystrixDashboard           //声明启用可视化数据监控
public class SpringcloudHystrixApplication {

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

}

5.运行注册中心，提供者，和 Hystrix模块入口

6.  http://localhost:8060/actuator/hystrix.stream 

这个界面一直ping输出
 

7.访问接口

http://localhost:8060/hystrix/select

8.  http://localhost:8060/hystrix  

这个打开hystrix仪表盘 ，可以输入http://localhost:8060/actuator/hystrix.stream 

9.跳转到页面