Hystrix快速搭建

Hystrix快速整合：

​ Hystrix在服务端和客户端都可以进行降级、熔断、限流

• POM依赖

        <!--netflix-hystrix-->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-hystrix</artifactId>
        </dependency>

• YML

  如果通过OpenFeign进行调用时，要开启Hystrix

feign:
  hystrix:
    enabled: true   # 在Feign中开启Hystix

• 主启动

@EnableCircuitBreaker或@EnableHystrix

@SpringBootApplication
@EnableDiscoveryClient
@EnableEurekaClient
@EnableCircuitBreaker
public class PaymentHystrixMain8001 {
    public static void main(String[] args) {
        SpringApplication.run(PaymentHystrixMain8001.class, args);
    }

    /**
     * 此配置是为了服务监控而配置，与服务容错本身无关，springcloud升级后的坑
     * ServletRegistrationBean因为springboot的默认路径不是"/hystrix.stream"
     * 只要在自己的项目里配置上下面的servlet就可以了
     *
     * @return
     */
    @Bean
    public ServletRegistrationBean getServlet() {
        HystrixMetricsStreamServlet streamServlet = new HystrixMetricsStreamServlet();
        ServletRegistrationBean registrationBean = new ServletRegistrationBean(streamServlet);
        registrationBean.setLoadOnStartup(1);
        registrationBean.addUrlMappings("/hystrix.stream");
        registrationBean.setName("HystrixMetricsStreamServlet");
        return registrationBean;
    }
}

服务端

• 业务类

  服务端进行处理： @HystrixCommand

    //===== 服务熔断
    @HystrixCommand(fallbackMethod = "paymentCircuitBreaker_fallback", commandProperties = {
            @HystrixProperty(name = "circuitBreaker.enabled", value = "true"),//开启断路器
            @HystrixProperty(name = "circuitBreaker.requestVolumeThreshold", value = "10"),//请求次数
            @HystrixProperty(name = "circuitBreaker.sleepWindowInMilliseconds", value = "10000"),//时间窗口期
            @HystrixProperty(name = "circuitBreaker.errorThresholdPercentage", value = "60")//失败率达到多少后跳闸
    })
    public String paymentCircuitBreaker(Integer id) {
        if (id < 0) {
            throw new RuntimeException("**** id 不能为负数 ***");
        }
        String serialNumber = IdUtil.simpleUUID();
        return Thread.currentThread().getName() + "\t" + "调用成功，流水号：" + serialNumber;
    }
    public String paymentCircuitBreaker_fallback(Integer id) {
        return "id 不能为负数，请稍后再试，id：" + id;
    }

客户端

结合feign进行客户端处理

@Service
@FeignClient(value = "CLOUD-PROVIDER-HYSTRIX-PAYMENT", fallback = PaymentFallbackService.class)
public interface PaymentHystrixService {

​ Controller进行全局处理

//@DefaultProperties(defaultFallback = "payment_Global_FallbackMethod")
public class OrderHystrixController {
    //下面是全局fallback方法
    public String payment_Global_FallbackMethod() {
        return "Global异常处理信息，请稍后重试";
    }
}

服务监控Hystrix Dashboard

搭建cloud-consumer-hystrix-dashboard9001

• POM

<?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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <parent>
        <artifactId>springcloud</artifactId>
        <groupId>com.example</groupId>
        <version>0.0.1-SNAPSHOT</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <artifactId>cloud-consumer-hystrix-dashboard9001</artifactId>

    <dependencies>
        <!--hystrix-dashboard 仪表盘图形化监控界面-->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-hystrix-dashboard</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <!--图形化监控-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>
        <!--devtools-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <scope>runtime</scope>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
        </dependency>
    </dependencies>
</project>

• yml

server:
  port: 9001

• 主启动

package com.example;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
import org.springframework.cloud.netflix.hystrix.dashboard.EnableHystrixDashboard;

@SpringBootApplication
@EnableDiscoveryClient
@EnableHystrixDashboard
public class HystrixDashboardMain9001 {
    public static void main(String[] args) {
        SpringApplication.run(HystrixDashboardMain9001.class, args);
    }
}

• 访问地址：http://localhost:9001/hystrix

9001监控8001

• 注意：新版本Hystrix需要在主启动类MainApplication中指定监控路径

@SpringBootApplication
@EnableDiscoveryClient
@EnableEurekaClient
@EnableCircuitBreaker
public class PaymentHystrixMain8001 {
    public static void main(String[] args) {
        SpringApplication.run(PaymentHystrixMain8001.class, args);
    }

    /**
     * 此配置是为了服务监控而配置，与服务容错本身无关，springcloud升级后的坑
     * ServletRegistrationBean因为springboot的默认路径不是"/hystrix.stream"
     * 只要在自己的项目里配置上下面的servlet就可以了
     *
     * @return
     */
    @Bean
    public ServletRegistrationBean getServlet() {
        HystrixMetricsStreamServlet streamServlet = new HystrixMetricsStreamServlet();
        ServletRegistrationBean registrationBean = new ServletRegistrationBean(streamServlet);
        registrationBean.setLoadOnStartup(1);
        registrationBean.addUrlMappings("/hystrix.stream");
        registrationBean.setName("HystrixMetricsStreamServlet");
        return registrationBean;
    }
}

• 在web界面填写监控地址：http://localhost:8001/hystrix.stream