SpringCloud学习笔记之服务容错保护Hystrix

程序员文章站 2022-06-12 15:23:13

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SpringCloud学习笔记之服务容错保护Hystrix.md

前言

在分布式架构中，当某个服务单元发生故障之后，通过断路器的故障监控，向调用方法返回一个错误响应，而不是长时间的等待。这样就不会使得线程因调用故障服务被长时间占用不释放，避免了故障在分布式系统中的蔓延。

Hystrix 具备服务降级、服务熔断、线程和信号隔离、请求缓存、请求合并以及服务监控等强大功能。

快速入门

断路器在客户端配置（消费者）

pom.xml 依赖

<?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">
    <modelVersion>4.0.0</modelVersion>

    <groupId>top.simba1949</groupId>
    <artifactId>spring-cloud-hystrix-consumer</artifactId>
    <version>1.0-SNAPSHOT</version>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.5.RELEASE</version>
        <relativePath /> <!-- lookup parent from repository -->
    </parent>

    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>Greenwich.RELEASE</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>

    <dependencies>
        <!--spring boot starter : Core starter, including auto-configuration support, logging and YAML-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
        </dependency>
        <!--spring boot starter test : Starter for testing Spring Boot applications with libraries including JUnit, Hamcrest and Mockito-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <!--spring boot starter actuator:
            Starter for using Spring Boot’s Actuator which provides production ready features to help you monitor and manage your application
        -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
        </dependency>
        <!--spring boot starter web : Starter for building web, including RestFul, applications using Spring MVC. Uses Tomcat as the default embedded container-->
        <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-ribbon</artifactId>
        </dependency>
        <!-- hystrix dependency -->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-hystrix</artifactId>
        </dependency>

    </dependencies>

    <build>
        <plugins>
            <!--编译插件-->
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <configuration>
                    <!-- 配置使用的 jdk 版本 -->
                    <target>1.8</target>
                    <source>1.8</source>
                </configuration>
            </plugin>
            <!--springboot-maven打包插件 和 热部署配置-->
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <configuration>
                    <fork>true</fork> <!-- 如果没有该配置，devtools不会生效 -->
                    <executable>true</executable><!--将项目注册到linux服务上，可以通过命令开启、关闭以及伴随开机启动等功能-->
                </configuration>
            </plugin>
            <!--资源拷贝插件-->
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-resources-plugin</artifactId>
                <configuration>
                    <encoding>UTF-8</encoding>
                </configuration>
            </plugin>
        </plugins>
        <!--IDEA是不会编译src的java目录的xml文件，如果需要读取，则需要手动指定哪些配置文件需要读取-->
        <resources>
            <resource>
                <directory>src/main/java</directory>
                <includes>
                    <include>**/*.xml</include>
                </includes>
            </resource>
            <resource>
                <directory>src/main/resources</directory>
                <includes>
                    <include>**/*</include>
                </includes>
            </resource>
        </resources>
    </build>
</project>

application.properties

注意：hystrix 可能会出现服务能够调用成功但是还会调用熔断回调方法，配置熔断时间即可

server.port=7000
spring.application.name=spring-cloud-hystrix-consumer

eureka.instance.hostname=localhost
eureka.client.service-url.defaultZone=http://${eureka.instance.hostname}:8081/eureka
# hystrix 可能会出现服务能够调用成功但是还会调用熔断回调方法，这里需要配置熔断时间
hystrix.command.default.execution.isolation.thread.timeoutInMilliseconds=10000

logging.level.root=debug

Ribbon 配置类

package top.simba1949.config;

import org.springframework.cloud.client.loadbalancer.LoadBalanced;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.client.RestTemplate;

/**
 * @author SIMBA1949
 * @date 2019/7/13 20:07
 */
@Configuration
public class RibbonConfig {

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

请求服务类

package top.simba1949.service;

import com.netflix.hystrix.contrib.javanica.annotation.HystrixCommand;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.ResponseEntity;
import org.springframework.stereotype.Service;
import org.springframework.web.client.RestTemplate;

/**
 * @author SIMBA1949
 * @date 2019/7/13 20:51
 */
@Service
public class HelloService {
    private static final String SERVICE_NAME = "http://SPRING-CLOUD-HYSTRIX-PROVIDER";
    @Autowired
    private RestTemplate restTemplate;

    @HystrixCommand(fallbackMethod = "sayFallback")
    public String say(String name) {
        ResponseEntity<String> resp = restTemplate.getForEntity(SERVICE_NAME + "/hello/" + name, String.class);
        String body = resp.getBody();
        return body;
    }

    /**
	 * 异常处理/熔断处理 需要添加 Throwable 对象来接收异常信息
	 *
	 * @param name
	 * @param e
	 * @return
	 */
    public String sayFallback(String name, Throwable e){
        return "Dear " + name +", This is error result : " + e.getMessage();
    }
}

控制层

package top.simba1949.controller;

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.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import top.simba1949.service.HelloService;

/**
 * @author SIMBA1949
 * @date 2019/7/13 20:05
 */
@RestController
@RequestMapping("hello")
public class HelloController {

    @Autowired
    private HelloService helloService;

    @GetMapping("{name}")
    public String say(@PathVariable(value = "name")String name){
        String result = helloService.say(name);
        return result;
    }
}

启动类

package top.simba1949;

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

/**
 * @EnableHystrix 开启断路器功能
 *
 * @author SIMBA1949
 * @date 2019/7/13 19:45
 */
@EnableHystrix
@EnableDiscoveryClient
@SpringBootApplication
public class Application {
    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }
}

Hystrix Dashboard 仪表盘

Hystrix Dashboard 主要用于实时监控 Hystrix 的各项指标信息。通过 Hystrix Dashboard 反馈的实时信息，可以帮助我们快速发现系统存在的问题，从而及时的采取措施。

Hystrix Dashboard 共支持三种不同的监控方式

默认的集群监控：通过 URL http://turbine-hostname:port/turbine.stream 开启，实现对默认集群的监控
指定的集群监控：通过 URL http://turbine-hostname:port/turbine.stream?cluster=[clusterName] 开启，实现对 clusterName 集群的监控
单体应用的监控：通过 URL http://hystrix-app:port/hystrix.stream 开启，实现对具体的某个服务实例的监控

1 和 2 都是对集群的监控，需要整合 Turbine 才能实现

单体应用的监控 Hystrix Dashboard

重要依赖

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-actuator</artifactId>
</dependency>
<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-netflix-hystrix</artifactId>
</dependency>
<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-netflix-hystrix-dashboard</artifactId>
</dependency>

pom.xml 依赖

<?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">
    <modelVersion>4.0.0</modelVersion>

    <groupId>top.simba1949</groupId>
    <artifactId>spring-cloud-hystrix-dashboard</artifactId>
    <version>1.0-SNAPSHOT</version>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.5.RELEASE</version>
        <relativePath /> <!-- lookup parent from repository -->
    </parent>

    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>Greenwich.RELEASE</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>

    <dependencies>
        <!--spring boot starter : Core starter, including auto-configuration support, logging and YAML-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
        </dependency>
        <!--spring boot starter test : Starter for testing Spring Boot applications with libraries including JUnit, Hamcrest and Mockito-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
        </dependency>
        <!--spring boot starter web : Starter for building web, including RestFul, applications using Spring MVC. Uses Tomcat as the default embedded container-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>


        <!--spring boot starter actuator:
            Starter for using Spring Boot’s Actuator which provides production ready features to help you monitor and manage your application
        -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.springframework.cloud/spring-cloud-starter-netflix-hystrix -->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-hystrix</artifactId>
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.springframework.cloud/spring-cloud-starter-netflix-hystrix-dashboard -->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-hystrix-dashboard</artifactId>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <!--编译插件-->
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <configuration>
                    <!-- 配置使用的 jdk 版本 -->
                    <target>1.8</target>
                    <source>1.8</source>
                </configuration>
            </plugin>
            <!--springboot-maven打包插件 和 热部署配置-->
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <configuration>
                    <fork>true</fork> <!-- 如果没有该配置，devtools不会生效 -->
                    <executable>true</executable><!--将项目注册到linux服务上，可以通过命令开启、关闭以及伴随开机启动等功能-->
                </configuration>
            </plugin>
            <!--资源拷贝插件-->
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-resources-plugin</artifactId>
                <configuration>
                    <encoding>UTF-8</encoding>
                </configuration>
            </plugin>
        </plugins>
        <!--IDEA是不会编译src的java目录的xml文件，如果需要读取，则需要手动指定哪些配置文件需要读取-->
        <resources>
            <resource>
                <directory>src/main/java</directory>
                <includes>
                    <include>**/*.xml</include>
                </includes>
            </resource>
            <resource>
                <directory>src/main/resources</directory>
                <includes>
                    <include>**/*</include>
                </includes>
            </resource>
        </resources>
    </build>
</project>

启动类

package top.simba1949;

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

/**
 * @EnableHystrixDashboard 开启监控面板
 * 
 * @author SIMBA1949
 * @date 2019/7/18 22:05
 */
@EnableHystrixDashboard
@SpringBootApplication
public class Application {
    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }
}

配置文件

server.port=8010
spring.application.name=spring-cloud-hystrix-dashboard
# 释放 hystrix.stream 端点
management.endpoints.web.exposure.include=hystrix.stream
# 可以注册到 eureka 中，示例没有注册到 eureka

访问测试

访问 http:// IP:PORT/hystrix

SpringCloud学习笔记之服务容错保护Hystrix

在 Hystrix Dashboard 查看三种方式

# 1
Cluster via Turbine (default cluster): http://turbine-hostname:port/turbine.stream 
# 2
Cluster via Turbine (custom cluster): http://turbine-hostname:port/turbine.stream?cluster=[clusterName]
# 3
Single Hystrix App: http://hystrix-app:port/actuator/hystrix.stream

问题及解决方案

# 问题一：Unable to connect to Command Metric Stream
需要在配置文件释放 hystrix.stream 端点，即在配置文件添加如下
management.endpoints.web.exposure.include=hystrix.stream

# 问题二：如果页面一直  loading 或者访问 http://IP:PORT/hystrix.stream 一直 ping
需要至少访问一次 @HystrixCommand 修饰的URL

使用 Turbine 聚合监控数据

上一篇：搭建K8s集群

下一篇： Linux下的crontab定时执行任务命令详解

SpringCloud学习笔记之服务容错保护Hystrix

SpringCloud学习笔记之服务容错保护Hystrix.md

前言

快速入门

pom.xml 依赖

application.properties

Ribbon 配置类

请求服务类

控制层

启动类

Hystrix Dashboard 仪表盘

单体应用的监控 Hystrix Dashboard

重要依赖

pom.xml 依赖

启动类

配置文件

访问测试

在 Hystrix Dashboard 查看三种方式

问题及解决方案

使用 Turbine 聚合监控数据

springcloud学习之路: (四) springcloud集成Hystrix服务保护

微服务架构实战学习笔记第五章 Spring Cloud Netflix Hystrix与服务容错

SpringCloud学习笔记之服务容错保护Hystrix

十、SpringCloud学习笔记之hystrix服务降级

springcloud学习之路: (四) springcloud集成Hystrix服务保护

Kite的学习历程SpringCloud之Hystrix服务降级

微服务架构实战学习笔记第五章 Spring Cloud Netflix Hystrix与服务容错

九、SpringCloud学习笔记之hystrix案例-Jmeter测试高并发访问

SpringCloud学习笔记之服务容错保护Hystrix

SpringCloud学习笔记之服务容错保护Hystrix.md

前言

快速入门

pom.xml 依赖

application.properties

Ribbon 配置类

请求服务类

控制层

启动类

Hystrix Dashboard 仪表盘

单体应用的监控 Hystrix Dashboard

重要依赖

pom.xml 依赖

启动类

配置文件

访问测试

在 Hystrix Dashboard 查看三种方式

问题及解决方案

使用 Turbine 聚合监控数据

springcloud学习之路: (四) springcloud集成Hystrix服务保护

微服务架构实战学习笔记 第五章 Spring Cloud Netflix Hystrix与服务容错

SpringCloud学习笔记之服务容错保护Hystrix

十、SpringCloud学习笔记之hystrix服务降级

springcloud学习之路: (四) springcloud集成Hystrix服务保护

Kite的学习历程SpringCloud之Hystrix服务降级

微服务架构实战学习笔记 第五章 Spring Cloud Netflix Hystrix与服务容错

九、SpringCloud学习笔记之hystrix案例-Jmeter测试高并发访问

微服务架构实战学习笔记第五章 Spring Cloud Netflix Hystrix与服务容错

微服务架构实战学习笔记第五章 Spring Cloud Netflix Hystrix与服务容错