Grafana+Prometheus係統監控之SpringBoot

前言

前一段時間使用SpringBoot創建了一個webhook項目，由於近期項目中也使用了不少SpringBoot相關的項目，趁著周末，配置一下使用prometheus監控微服務Springboot。

項目配置

引入坐標

<!-- 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("項目啟動 ");
    }
}

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(計數)：

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(統計請求時間)：

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

主要是為了測試攔截器的效果

@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));
     }
}

以上都配置完成後啟動項目即可。

配置Prometheus

vi prometheus.yml

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

保存後重新啟動Prometheus即可。

訪問https://ip/targets 服務State 為up說明配置成功，查閱很多教程都說需要配置 spring.metrics.servo.enabled=false，否則在prometheus的控製台的targets頁簽裏，會一直顯示此endpoint為down狀態，然貌似並沒有配置也是ok的。