Grafana+Prometheus系统监控之SpringBoot

前言

前一段时间使用SpringBoot创建了一个webhook项目，由于近期项目中也使用了不少SpringBoot相关的项目，趁着周末，配置一下使用prometheus监控微服务Springboot。

项目配置

引入坐标

<!-- Exposition spring_boot -->
<dependency>
	<groupId>io.prometheus</groupId>
	<artifactId>simpleclient_spring_boot</artifactId>
	<version>0.1.0</version>
</dependency>
<!-- Hotspot JVM metrics -->
<dependency>
	<groupId>io.prometheus</groupId>
	<artifactId>simpleclient_hotspot</artifactId>
	<version>0.1.0</version>
</dependency>
<!-- Exposition servlet -->
<dependency>
	<groupId>io.prometheus</groupId>
	<artifactId>simpleclient_servlet</artifactId>
	<version>0.1.0</version>
</dependency>

配置Application

@SpringBootApplication
@EnablePrometheusEndpoint
@EnableSpringBootMetricsCollector
public class Application  {
	private static final Logger logger = LoggerFactory.getLogger(Application.class);
	public static void main(String[] args) throws InterruptedException {
		SpringApplication.run(Application.class, args);
		logger.info("项目启动 ");
	}
}

配置MonitoringConfig

@Configuration
class MonitoringConfig {
    @Bean
    SpringBootMetricsCollector springBootMetricsCollector(Collection<PublicMetrics> publicMetrics) {

        SpringBootMetricsCollector springBootMetricsCollector = new SpringBootMetricsCollector(publicMetrics);
        springBootMetricsCollector.register();
        return springBootMetricsCollector;
    }

    @Bean
    ServletRegistrationBean servletRegistrationBean() {
        DefaultExports.initialize();
        return new ServletRegistrationBean(new MetricsServlet(), "/prometheus");
    }
}

配置Interceptor

RequestCounterInterceptor(计数)：

public class RequestCounterInterceptor extends HandlerInterceptorAdapter {

    // @formatter:off
    // Note (1)
    private static final Counter requestTotal = Counter.build()
         .name("http_requests_total")
         .labelNames("method", "handler", "status")
         .help("Http Request Total").register();
    // @formatter:on

    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception e)
                                                                                                         throws Exception {
         // Update counters
         String handlerLabel = handler.toString();
         // get short form of handler method name
         if (handler instanceof HandlerMethod) {
              Method method = ((HandlerMethod) handler).getMethod();
              handlerLabel = method.getDeclaringClass().getSimpleName() + "." + method.getName();
         }
         // Note (2)
         requestTotal.labels(request.getMethod(), handlerLabel, Integer.toString(response.getStatus())).inc();
    }
}

RequestTimingInterceptor(统计请求时间)：

package com.itstyle.webhook.interceptor;
import java.lang.reflect.Method;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import io.prometheus.client.Summary;
import org.springframework.web.method.HandlerMethod;
import org.springframework.web.servlet.handler.HandlerInterceptorAdapter;

public class RequestTimingInterceptor extends HandlerInterceptorAdapter {

    private static final String REQ_PARAM_TIMING = "timing";

    // @formatter:off
    // Note (1)
    private static final Summary responseTimeInMs = Summary
         .build()
         .name("http_response_time_milliseconds")
         .labelNames("method", "handler", "status")
         .help("Request completed time in milliseconds")
         .register();
    // @formatter:on

    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
         // Note (2)
         request.setAttribute(REQ_PARAM_TIMING, System.currentTimeMillis());
         return true;
    }

    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex)throws Exception {
         Long timingAttr = (Long) request.getAttribute(REQ_PARAM_TIMING);
         long completedTime = System.currentTimeMillis() - timingAttr;
         String handlerLabel = handler.toString();
         // get short form of handler method name
         if (handler instanceof HandlerMethod) {
              Method method = ((HandlerMethod) handler).getMethod();
              handlerLabel = method.getDeclaringClass().getSimpleName() + "." + method.getName();
         }
       // Note (3)
       responseTimeInMs.labels(request.getMethod(), handlerLabel, 
    		                   Integer.toString(response.getStatus())).observe(completedTime);
    }
}

配置Controller

主要是为了测试拦截器的效果

@RestController
public class HomeController {
     private static final Logger logger = LoggerFactory.getLogger(HomeController.class);
 
     @RequestMapping("/endpointA")
     public void handlerA() throws InterruptedException {
          logger.info("/endpointA");
          Thread.sleep(RandomUtils.nextLong(0, 100));
     }
 
     @RequestMapping("/endpointB")
     public void handlerB() throws InterruptedException {
          logger.info("/endpointB");
          Thread.sleep(RandomUtils.nextLong(0, 100));
     }
}

以上都配置完成后启动项目即可。

配置Prometheus

vi prometheus.yml

  - job_name: webhook
    metrics_path: '/prometheus'
    static_configs:
     - targets: ['localhost:8080']
       labels:
         instance: webhook

保存后重新启动Prometheus即可。

访问http://ip/targets 服务State 为up说明配置成功，查阅很多教程都说需要配置 spring.metrics.servo.enabled=false，否则在prometheus的控制台的targets页签里，会一直显示此endpoint为down状态，然貌似并没有配置也是ok的。