一:框架
springboot、hystrix、maven
二:depend
[html] view plain copy print ? <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> <version>${springboot.version}</version> </dependency> <dependency> <groupId>com.netflix.hystrix</groupId> <artifactId>hystrix-core</artifactId> <version>${hystrix.version}</version> </dependency> <dependency> <groupId>com.netflix.hystrix</groupId> <artifactId>hystrix-metrics-event-stream</artifactId> <version>${hystrix.version}</version> </dependency> <dependency> <groupId>com.netflix.hystrix</groupId> <artifactId>hystrix-javanica</artifactId> <version>${hystrix.version}</version> </dependency> 三:下载hystrix-dashboard-1.5.5.war
地址:http://search.maven.org/remotecontent?filepath=com/netflix/hystrix/hystrix-dashboard/1.5.5/hystrix-dashboard-1.5.5.war
然后部署到tomcat容器中,此处省略步骤,不会的找块豆腐撞死TAT
部署完成后访问http://127.0.0.1:8080/hystrix-dashboard-1.5.5/,可以看到如下图
四:部署一个web应用
此处用springboot开发了一个简单的ok web应用,起主要作用的有两个类HystrixConfiguration.Java和MainServer.java
HystrixConfiguration:注册spring bean和servlet
MainServer:服务应用入口
代码如下:
[java] view plain copy print ? package com.eden.main; import java.util.Random; import java.util.concurrent.TimeUnit; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RequestMethod; import org.springframework.web.bind.annotation.RestController; import com.netflix.hystrix.contrib.javanica.annotation.HystrixCommand; import com.netflix.hystrix.contrib.javanica.annotation.HystrixProperty; /** * @author eden.ding1991@gmail.com 2016年8月31日 上午10:02:06 */ @SpringBootApplication @RestController public class MainServer { private static final Logger LOG = LoggerFactory.getLogger(MainServer.class); public static void main(String[] args) { SpringApplication.run(MainServer.class, args); } @RequestMapping(value = "/ok", method = RequestMethod.GET) @HystrixCommand(fallbackMethod = "okFallback", threadPoolProperties = { @HystrixProperty(name = "coreSize", value = "30"), @HystrixProperty(name = "maxQueueSize", value = "100"), @HystrixProperty(name = "queueSizeRejectionThreshold", value = "20") }, commandProperties = { @HystrixProperty(name = "execution.isolation.thread.timeoutInMilliseconds", value = "100"), @HystrixProperty(name = "circuitBreaker.requestVolumeThreshold", value = "50") }) public String ok() throws Exception { int l = new Random().nextInt(200); LOG.info(String.format("l=%s", l)); TimeUnit.MILLISECONDS.sleep(l); return "ok"; } public String okFallback(Throwable e) { System.out.println("execute okFallback!" + e.getMessage()); LOG.error("error", e); return "fallback"; } } [java] view plain copy print ? package com.eden.main.hystrix; import org.springframework.boot.web.servlet.ServletRegistrationBean; import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.Configuration; import com.netflix.hystrix.contrib.javanica.aop.aspectj.HystrixCommandAspect; import com.netflix.hystrix.contrib.metrics.eventstream.HystrixMetricsStreamServlet; /** * * @author eden.ding1991@gmail.com 2016年8月31日 上午11:14:16 */ @Configuration public class HystrixConfiguration { //注册Hystrix框架的拦截器,使得框架的注解能够生效 @Bean public HystrixCommandAspect hystrixAspect() { return new HystrixCommandAspect(); } //注入servlet,拦截url="/hystrix.stream" //测试git dev commit @Bean public ServletRegistrationBean hystrixMetricsStreamServlet() { ServletRegistrationBean registration = new ServletRegistrationBean(new HystrixMetricsStreamServlet()); registration.addUrlMappings("/hystrix.stream"); return registration; } }
@HystrixProperty这个部分注解的含义请参考hystrix的github https://github.com/Netflix/Hystrix/wiki/Configuration
五:启动这个简单的web应用,访问http://127.0.0.1:8081/ok
端口号是8081,这个地方注意,为了防止与dashboard冲突,所以在web应用的application.yml将端口号改成了8081
上面注册的spring bean中有一个servlet是HystrixMetricsStreamServlet,拦截的url是/hystrix.stream,这个地方主要是生成监控需要的数据,可以直接访问这个url:http://127.0.0.1:8081/hystrix.stream 你会看到不停生成一个json格式的数据,里面全是监控的服务的各项metrics
六:开启监控上述web应用
七:监控界面
上述界面是用的测试案例中模拟的,并发60个线程访问,超时时间随机数0-200,系统设计的阈值是100ms,所以看到上图中有28个请求超出阈值导致熔断器打开,然后从界面中也能看到多少请求成功,多少失败,错误率,活跃线程数,排队线程数等