如何将Prometheus Metrics重定向到默认的spring boot服务器

Question

我正在尝试从我的Spring启动应用程序中公开自定义仪表指标。我正在使用千分尺和普罗米修斯注册表来做到这一点。我已经设置了普罗米修斯注册和配置根据 - 千分尺样本 - Github，但它创建了一个HTTP服务器来公开普罗米修斯指标。我需要将所有指标重定向或公开到Spring boot的默认上下文路径 - /actuator/prometheus，而不是新端口上的新上下文路径。到目前为止，我已经实现了以下代码 -

PrometheusRegistry.java-

package com.xyz.abc.prometheus;

import java.io.IOException;
import java.io.OutputStream;
import java.net.InetSocketAddress;
import java.time.Duration;

import com.sun.net.httpserver.HttpServer;

import io.micrometer.core.lang.Nullable;
import io.micrometer.prometheus.PrometheusConfig;
import io.micrometer.prometheus.PrometheusMeterRegistry;

public class PrometheusRegistry {

    public static PrometheusMeterRegistry prometheus() {
        PrometheusMeterRegistry prometheusRegistry = new PrometheusMeterRegistry(new PrometheusConfig() {
            @Override
            public Duration step() {
                return Duration.ofSeconds(10);
            }

            @Override
            @Nullable
            public String get(String k) {
                return null;
            }
        });

        try {
            HttpServer server = HttpServer.create(new InetSocketAddress(8081), 0);
            server.createContext("/sample-data/prometheus", httpExchange -> {
                String response = prometheusRegistry.scrape();
                httpExchange.sendResponseHeaders(200, response.length());
                OutputStream os = httpExchange.getResponseBody();
                os.write(response.getBytes());
                os.close();
            });

            new Thread(server::start).run();
        } catch (IOException e) {
            throw new RuntimeException(e);
        }

        return prometheusRegistry;
    }
    
}

MicrometerConfig.java-

package com.xyz.abc.prometheus;

import io.micrometer.core.instrument.MeterRegistry;


public class MicrometerConfig {

    public static MeterRegistry carMonitoringSystem() {
        // Pick a monitoring system here to use in your samples.
        return PrometheusRegistry.prometheus();
    }
}

代码段，我正在创建自定义仪表指标。截至目前，这是一个简单的REST API进行测试 - （请阅读中间的评论）

@SuppressWarnings({ "unchecked", "rawtypes" })
@RequestMapping(value = "/sampleApi", method= RequestMethod.GET)
@ResponseBody
//This Timed annotation is working fine and this metrics comes in /actuator/prometheus by default
@Timed(value = "car.healthcheck", description = "Time taken to return healthcheck")
public ResponseEntity healthCheck(){
    MeterRegistry registry = MicrometerConfig.carMonitoringSystem();
    AtomicLong n = new AtomicLong();
    //Starting from here none of the Gauge metrics shows up in /actuator/prometheus path instead it goes to /sample-data/prometheus on port 8081 as configured.
    registry.gauge("car.gauge.one", Tags.of("k", "v"), n);
    registry.gauge("car.gauge.two", Tags.of("k", "v1"), n, n2 -> n2.get() - 1);
    registry.gauge("car.help.gauge", 89);
    
    //This thing never works! This gauge metrics never shows up in any URI configured
    Gauge.builder("car.gauge.test", cpu)
         .description("car.device.cpu")
         .tags("customer", "demo")
         .register(registry);
    return new ResponseEntity("Car is working fine.", HttpStatus.OK);
}

我需要所有的指标都显示在-< code >/actuator/Prometheus 中，而不是创建一个新的HTTP服务器。我知道我正在显式地创建一个新的HTTP服务器，所以这里会出现一些指标。请告诉我如何避免创建一个新的HTTP服务器，并将所有prometheus指标重定向到默认路径-< code >/actuator/Prometheus 。此外，如果我使用< code>Gauge.builder来定义一个自定义的计量器指标，它永远不会工作。请解释我如何才能使这一工作。让我知道我哪里做错了。谢谢你。

Answer 1

每次调用＜code＞microConfig时。carMonitoringSystem（）它正在创建一个新的prometheus注册表（并尝试启动一个新服务器）

您需要在创建仪表的类中注入计量注册，并以这种方式使用注入的计量注册。