springboot接入Prometheus實現自定義指標

前言

目前翻閱了網上的各種代碼集成Prometheus的demo，千篇一律，基本都是復制粘貼，均是1.x版本的springboot且代碼都是跑不通的。現根據開源依賴debug源碼，實踐出可用版本。
完整代碼地址 gitee-yonyong/my-prometheus
此代碼親測可用。

版本

io.micrometer 1.2.1
springboot 2.0.5.RELEASE

本代碼實現功能

1.Java接入Prometheus，提供JVM監控及自定義指標監控
2.實現自定義指標的接入功能
3.實現指標label動態賦值功能

代碼片段

build.gradle

    compile "io.prometheus:simpleclient_hotspot:0.0.24"
    compile "io.micrometer:micrometer-registry-prometheus:1.2.1"
    compile "io.micrometer:micrometer-core:1.2.1"

注冊MeterRegistry

 @Bean(value = "meterRegistryCustomizer")
    MeterRegistryCustomizer<MeterRegistry> meterRegistryCustomizer() {
        return meterRegistry -> meterRegistry.config()
                .commonTags("application", "springboot-app");
    }

MyMetrics 自定義指標

    /**
     * 計數器可以用於記錄只會增加不會減少的指標類型，比如記錄應用請求的總量(http_requests_total)，
     * cpu使用時間(process_cpu_seconds_total)等。 一般而言，Counter類型的metrics指標在命名中
     * 我們使用_total結束。
     */
    public static Counter requestCounter = Counter.build()
            .name("io_namespace_http_requests_total")
            .labelNames("path", "method", "code")
            .help("Total requests.").register();

注冊自定義指標

@Component
public class InitPrometheus implements ApplicationListener<ContextRefreshedEvent> {

    @Resource
    PrometheusMeterRegistry meterRegistry;

    @Override
    public void onApplicationEvent(ContextRefreshedEvent event) {
        new MyMetrics();

        CollectorRegistry prometheusRegistry = meterRegistry.getPrometheusRegistry();

        prometheusRegistry.register(MyMetrics.requestCounter);
        prometheusRegistry.register(MyMetrics.inprogressRequests);
        prometheusRegistry.register(MyMetrics.requestLatencyHistogram);
        prometheusRegistry.register(MyMetrics.requestLatency);
    }
}

使用

配置攔截器

@Configuration
public class AppConfig extends WebMvcConfigurationSupport {

    @Override
    protected void addInterceptors(InterceptorRegistry registry) {

        registry.addInterceptor(new PrometheusMetricsInterceptor()).addPathPatterns("/**");
        super.addInterceptors(registry);
    }
}

攔截器為指標賦值

public class PrometheusMetricsInterceptor extends HandlerInterceptorAdapter {


    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        String requestURI = request.getRequestURI();
        String method = request.getMethod();
        int status = response.getStatus();

        MyMetrics.inprogressRequests.labels(requestURI,method).inc();

        MyMetrics.histogramRequestTimer = MyMetrics.requestLatencyHistogram.labels(requestURI, method, String.valueOf(status)).startTimer();

        MyMetrics.requestTimer = MyMetrics.requestLatency.labels(requestURI, method, String.valueOf(status)).startTimer();
        return super.preHandle(request, response, handler);
    }

    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
        String requestURI = request.getRequestURI();
        String method = request.getMethod();
        int status = response.getStatus();

        MyMetrics.requestCounter.labels(requestURI, method, String.valueOf(status)).inc();

        MyMetrics.inprogressRequests.labels(requestURI,method).dec();

        MyMetrics.histogramRequestTimer.observeDuration();

        MyMetrics.requestTimer.observeDuration();

        super.afterCompletion(request, response, handler, ex);
    }
}

啟動項目，查看服務指標信息

http://localhost:8502/metrics/prometheus