服务容错保护SpringCloud Hystrix

不念不忘少年蓝@ 2022-05-09 04:16 300阅读 0赞

# 服务容错保护SpringCloud Hystrix #

### 文章目录 ###

*  服务容错保护SpringCloud Hystrix
 *   *  一、快速入门
     *  二、请求合并
     *  三、Hystrix 仪表盘
     *  四、Turbine 集群监控

## 一、快速入门 ##

eureka 9001  
userservice 9003  
userservice 9006  
ribbonconsumer 9005

在 ribbonconsumer 中加入 pom 依赖

<dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-hystrix</artifactId>
        <version>1.4.5.RELEASE</version>
    </dependency>

在 ribbonconsumer 工程的主类 SpringcloudRibbonConsumerApplication 中使用 @EnableCircuitBreaker 注解开启断路器功能

@SpringBootApplication @EnableDiscoveryClient @EnableCircuitBreaker public class SpringcloudRibbonConsumerApplication { @Bean @LoadBalanced RestTemplate restTemplate(){ return new RestTemplate(); } public static void main(String[] args) { SpringApplication.run(SpringcloudRibbonConsumerApplication.class, args); } }

还可以使用 SpringCloud 应用中的 @SpringCloudApplication 注解来修饰应用主类，该注解中包含了上述所引用的三个注解

@SpringCloudApplication public class SpringcloudRibbonConsumerApplication { @Bean @LoadBalanced RestTemplate restTemplate(){ return new RestTemplate(); } public static void main(String[] args) { SpringApplication.run(SpringcloudRibbonConsumerApplication.class, args); } }

改造服务消费方式，在 helloService 函数上增加 @HystrixCommand 注解来指定回调方法

@Service public class HelloService { @Autowired RestTemplate restTemplate; @HystrixCommand(fallbackMethod = "helloFallback") public String helloService(){ long start = System.currentTimeMillis(); String result = restTemplate.exchange("http://SERIVCE-USER/hello", HttpMethod.GET, null, String.class).getBody(); System.out.println("spend time :" + (System.currentTimeMillis() - start)); return result; } public String helloFallback(){ return "error"; } }

@RestController public class ConsumerController { @Autowired RestTemplate restTemplate; @Autowired HelloService helloService; @GetMapping(value = "ribbon-consumer") public Object helloConsumer(){ return helloService.helloService(); //return restTemplate.exchange("http://SERIVCE-USER/hello", HttpMethod.GET, null, String.class).getBody(); //return restTemplate.getForEntity("http://SERIVCE-USER/hello",String.class).getBody(); } }

修改 userservice 9003

@RestController @Slf4j public class HelloController { @GetMapping(value = "/hello") public String hello() throws InterruptedException { int sleepTime = new Random().nextInt(3000); log.info("sleepTime:"+sleepTime); Thread.sleep(sleepTime); return "Hello World 9003"; } }

重启 userservice 9003 和 ribbonconsumer 9005 后，连续访问 [http://localhost:9005/ribbon-consumer][http_localhost_9005_ribbon-consumer] 几次，当 userservice 9003 Spend time 大于 2000 的时候，就会返回 error，即服务消费者因调用的服务潮湿从而触发熔断请求，并调用回调逻辑返回结果。

Hystrix 默认超时时间为 2000 毫秒

## 二、请求合并 ##

[Spring Cloud中Hystrix的请求合并][Spring Cloud_Hystrix]

服务提供者 SERIVCE-USER 9003 修改

@GetMapping(value = "/getUserInfo/{id}") public User getUserInfo(@PathVariable String id){ return new User("张三","123"); } @GetMapping(value = "/getUserInfos/{ids}") public List<User> getUserInfos(@PathVariable String ids){ System.out.println("getUserInfos---------"+ids+"Thread.currentThread().getName():" + Thread.currentThread().getName()); List<User> list = new ArrayList<>(); list.add(new User("张三","123")); list.add(new User("李四","1234")); list.add(new User("王五","12345")); return list; }

服务消费者

RIBBON-CONSUMER 9005

UserService

@Service public class UserService { @Autowired RestTemplate restTemplate; public String getUserInfo(Long id) { return restTemplate.exchange("http://SERIVCE-USER/getUserInfo/1", HttpMethod.GET, null, String.class).getBody(); } public String getUserInfos(List<Long> ids) { String usr = "http://SERIVCE-USER/getUserInfos/"+ids.toString(); String result = restTemplate.exchange(usr, HttpMethod.GET, null, String.class).getBody(); return result; } }

UserBatchCommand 批处理命令，继承自HystrixCommand，用来处理合并之后的请求

public class UserBatchCommand extends HystrixCommand<List<User>> { private List<Long> ids; @Autowired UserService userService; public UserBatchCommand(List<Long> ids, UserService userService) { super(Setter.withGroupKey(HystrixCommandGroupKey.Factory.asKey("CollapsingGroup")) .andCommandKey(HystrixCommandKey.Factory.asKey("CollapsingKey"))); this.ids = ids; this.userService = userService; } @Override protected List<User> run(){ String result = userService.getUserInfos(ids); List<User> users = JSONObject.parseArray(result,User.class); return users; } }

UserCollapseCommand 继承自HystrixCollapser来实现请求合并

public class UserCollapseCommand extends HystrixCollapser<List<User>, User, Long> { private UserService userService; private Long id; public UserCollapseCommand(UserService userService, Long id) { super(Setter.withCollapserKey(HystrixCollapserKey.Factory.asKey("userCollapseCommand")).andCollapserPropertiesDefaults(HystrixCollapserProperties.Setter().withTimerDelayInMilliseconds(100))); this.userService = userService; this.id = id; } @Override public Long getRequestArgument() { return id; } @Override protected HystrixCommand<List<User>> createCommand(Collection<CollapsedRequest<User, Long>> collapsedRequests) { List<Long> ids = new ArrayList<>(collapsedRequests.size()); ids.addAll(collapsedRequests.stream().map(CollapsedRequest::getArgument).collect(Collectors.toList())); UserBatchCommand userBatchCommand = new UserBatchCommand(ids, userService); return userBatchCommand; } @Override protected void mapResponseToRequests(List<User> batchResponse, Collection<CollapsedRequest<User, Long>> collapsedRequests) { System.out.println("mapResponseToRequests"); int count = 0; for (CollapsedRequest<User, Long> collapsedRequest : collapsedRequests) { User user = batchResponse.get(count++); collapsedRequest.setResponse(user); } } }

*  1.首先在构造方法中，我们设置了请求时间窗为100ms，即请求时间间隔在100ms之内的请求会被合并为一个请求。
 *  2.createCommand方法主要用来合并请求，在这里获取到各个单个请求的id，将这些单个的id放到一个集合中，然后再创建出一个BookBatchCommand对象，用该对象去发起一个批量请求。
 *  3.mapResponseToRequests方法主要用来为每个请求设置请求结果。该方法的第一个参数batchResponse表示批处理请求的结果，第二个参数collapsedRequests则代表了每一个被合并的请求，然后我们通过遍历batchResponse来为collapsedRequests设置请求结果。

测试

@RequestMapping("/test7") public void getUserBatchTest() throws ExecutionException, InterruptedException { HystrixRequestContext context = HystrixRequestContext.initializeContext(); UserCollapseCommand bc1 = new UserCollapseCommand(userService, 1l); UserCollapseCommand bc2 = new UserCollapseCommand(userService, 2l); UserCollapseCommand bc3 = new UserCollapseCommand(userService, 3l); UserCollapseCommand bc4 = new UserCollapseCommand(userService, 4l); Future<User> q1 = bc1.queue(); Future<User> q2 = bc2.queue(); Future<User> q3 = bc3.queue(); User user1 = q1.get(); User user2 = q2.get(); User user3 = q3.get(); Thread.sleep(3000); Future<User> q4 = bc4.queue(); User user4 = q4.get(); System.out.println("user1>>>"+user1); System.out.println("user2>>>"+user2); System.out.println("user3>>>"+user3); System.out.println("user4>>>"+user4); context.close(); }

*  1.首先要初始化 HystrixRequestContext
 *  2.创建 UserCollapseCommand 类的实例来发起请求，先发送3个请求，然后睡眠3秒钟，再发起1个请求，这样，前3个请求就会被合并为一个请求，第四个请求因为间隔的时间比较久，所以不会被合并，而是单独创建一个线程去处理。

控制台输出

getUserInfos---------[1, 2, 3]Thread.currentThread().getName():http-nio-9003-exec-2
    getUserInfos---------[4]Thread.currentThread().getName():http-nio-9003-exec-3

通过注解实现请求合并

在UserService中添加两个方法，如下：

@HystrixCollapser(batchMethod = "test11",collapserProperties = { @HystrixProperty(name ="timerDelayInMilliseconds",value = "100")}) public Future<User> test10(Long id) { return null; } @HystrixCommand public List<User> test11(List<Long> ids) { String usr = "http://SERIVCE-USER/getUserInfos/"+ids.toString(); String result = restTemplate.exchange(usr, HttpMethod.GET, null, String.class).getBody(); List<User> users = JSONObject.parseArray(result,User.class); return users; }

在test10方法上添加@HystrixCollapser注解实现请求合并，用batchMethod属性指明请求合并后的处理方法，collapserProperties属性指定其他属性。

调用

@RequestMapping("/test8") @ResponseBody public void test8() throws ExecutionException, InterruptedException { HystrixRequestContext context = HystrixRequestContext.initializeContext(); Future<User> f1 = userService.test10(1l); Future<User> f2 = userService.test10(2l); Future<User> f3 = userService.test10(3l); User b1 = f1.get(); User b2 = f2.get(); User b3 = f3.get(); Thread.sleep(3000); Future<User> f4 = userService.test10(4l); User b4 = f4.get(); System.out.println("b1>>>"+b1); System.out.println("b2>>>"+b2); System.out.println("b3>>>"+b3); System.out.println("b4>>>"+b4); context.close(); }

执行结果同之前一样

getUserInfos---------[1, 3, 2]Thread.currentThread().getName():http-nio-9003-exec-1
    getUserInfos---------[4]Thread.currentThread().getName():http-nio-9003-exec-2

## 三、Hystrix 仪表盘 ##

[解决Hystrix Dashboard 一直是Loading …的情况][Hystrix Dashboard _Loading]

[Hystrix仪表盘监控单实例节点][Hystrix]

[spring cloud2 hystrix没有hystrix.stream路径解决方案][spring cloud2 hystrix_hystrix.stream]

构建 hystrix-dashboard 9007

pom 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>com.zk.springcloud</groupId>
        <artifactId>springcloud-hystrix-dashboard</artifactId>
        <version>0.0.1-SNAPSHOT</version>
        <packaging>jar</packaging>
    
        <name>springcloud-hystrix-dashboard</name>
        <description>Demo project for Spring Boot</description>
    
        <parent>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-parent</artifactId>
            <version>2.0.5.RELEASE</version>
            <relativePath/> 
        </parent>
    
        <properties>
            <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
            <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
            <java.version>1.8</java.version>
            <spring-cloud.version>Finchley.SR1</spring-cloud.version>
        </properties>
    
        <dependencies>
            <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>
    
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-test</artifactId>
                <scope>test</scope>
            </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>

为应用主类加上 @EnableHystrixDashboard ， 启用 Hystrix Dashboard 功能

spring.application.name=hystrix-dashboard
    server.port=9007

启动该应用，访问 [http://localhost:9007/hystrix/][http_localhost_9007_hystrix] 可以看到 Hystrix Dashboard

在 ribbon-consumer 9005 的 dependencies 节点新增 spring-boot-starter-actuator 监控模块以开启监控相关的端点，并确保已经引入断路器的依赖  
spring-cloud-starter-hystrix

<dependency>
               <groupId>org.springframework.cloud</groupId>
               <artifactId>spring-cloud-starter-hystrix</artifactId>
               <version>1.4.5.RELEASE</version>
           </dependency>
    
           <dependency>
               <groupId>org.springframework.boot</groupId>
               <artifactId>spring-boot-starter-actuator</artifactId>
           </dependency>

在 ribbon-consumer 9005 确保在服务实例的主类中已经使用 @EnableCircuitBreaker 注解，开启了断路器功能，在启动类中加入如下代码

@Bean public ServletRegistrationBean getServlet(){ HystrixMetricsStreamServlet streamServlet = new HystrixMetricsStreamServlet(); ServletRegistrationBean registrationBean = new ServletRegistrationBean(streamServlet); registrationBean.setLoadOnStartup(1); //系统启动时加载顺序 registrationBean.addUrlMappings("/hystrix.stream");//路径 registrationBean.setName("HystrixMetricsStreamServlet"); return registrationBean; }

这样就可以直接使用 [http://localhost:9005/hystrix.stream][http_localhost_9005_hystrix.stream] 查看监控信息

重启 ribbon-consumer ，在 Hystrix Dashboard 的首页输入 [http://localhost:9005/hystrix.stream][http_localhost_9005_hystrix.stream] 就是用于 Hystrix Dashboard 来占线监控信息的接口

## 四、Turbine 集群监控 ##

[Spring Cloud：Turbine监控数据聚合【Finchley 版】Could not initiate connection to host, giving up: \[xxx\]][Spring Cloud_Turbine_Finchley _Could not initiate connection to host_ giving up_ _xxx]

创建 turbine 项目

pom 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>com.zk.springcloud.turbie</groupId>
        <artifactId>springcloud-turbie</artifactId>
        <version>0.0.1-SNAPSHOT</version>
        <packaging>jar</packaging>
    
        <name>springcloud-turbie</name>
        <description>Demo project for Spring Boot</description>
    
        <parent>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-parent</artifactId>
            <version>2.0.5.RELEASE</version>
            <relativePath/> 
        </parent>
    
        <properties>
            <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
            <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
            <java.version>1.8</java.version>
            <spring-cloud.version>Finchley.SR1</spring-cloud.version>
        </properties>
    
        <dependencies>
    
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-starter-hystrix</artifactId>
                <version>1.4.5.RELEASE</version>
            </dependency>
    
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-starter-hystrix-dashboard</artifactId>
                <version>1.4.5.RELEASE</version>
            </dependency>
    
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-actuator</artifactId>
            </dependency>
    
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-actuator</artifactId>
            </dependency>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-starter-netflix-turbine</artifactId>
            </dependency>
    
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-test</artifactId>
                <scope>test</scope>
            </dependency>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-netflix-hystrix-dashboard</artifactId>
                <version>2.0.1.RELEASE</version>
                <scope>compile</scope>
            </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>

在 application.properties 中加入 Eureka 和 Turbine 的相关配置

spring.application.name=turbie
    server.port=9008
    management.server.port=9009
    
    eureka.client.service-url.defaultZone=http://localhost:9001/eureka/,http://localhost:9004/eureka/
    
    turbine.app-config=RIBBON-CONSUMER
    turbine.cluster-name-expression="default"
    turbine.combine-host-port=true
    turbine.instanceUrlSuffix.default = /hystrix.stream

访问 [http://localhost:9008/hystrix/][http_localhost_9008_hystrix] 开启对 [http://localhost:9008/turbine.stream][http_localhost_9008_turbine.stream] 的监控

[http_localhost_9005_ribbon-consumer]: http://localhost:9005/ribbon-consumer
[Spring Cloud_Hystrix]: https://segmentfault.com/a/1190000011468804
[Hystrix Dashboard _Loading]: https://www.cnblogs.com/hejianjun/p/8670693.html
[Hystrix]: https://blog.csdn.net/chengqiuming/article/details/81583994
[spring cloud2 hystrix_hystrix.stream]: https://www.jianshu.com/p/4cb1c48a9053
[http_localhost_9007_hystrix]: http://localhost:9007/hystrix/
[http_localhost_9005_hystrix.stream]: http://localhost:9005/hystrix.stream
[Spring Cloud_Turbine_Finchley _Could not initiate connection to host_ giving up_ _xxx]: https://blog.csdn.net/Keith_Walker/article/details/80579190
[http_localhost_9008_hystrix]: http://localhost:9008/hystrix/
[http_localhost_9008_turbine.stream]: http://localhost:9008/turbine.stream