Micrometer ile Metrik Yazmak

Giriş

Metric'leri loglamak için io.micrometer.core.instrument.logging.LoggingMeterRegistry sınıfı kullanılır. Açıklaması şöyle

To be able to send custom metrics we need to import MeterRegistry from the Micrometer library and inject it into our class. 

It is possible to instantiate these types of meters from MeterRegistry:

- Counter: reports merely a count over a specified property of an application

- Gauge: shows the current value of a meter

- Timers: measures latencies or frequency of events

- DistributionSummary: provides distribution of events and a simple summary

Counter vs. gauge, summary vs. histogram yazısına bakabilirsiniz

Gradle

Şöyle yaparız

implementation 'org.springframework.boot:spring-boot-starter-actuator:2.6.3'
implementation 'io.micrometer:micrometer-registry-atlas:1.8.2'
implementation 'io.micrometer:micrometer-registry-prometheus:1.8.2'

MeterRegistryCustomizer Sınıfı

Örnek

Şöyle yaparız

@Configuration
public class MicroSvcMeterRegistryConfig {
  @Value("${spring.application.name}")
  String appName;

  @Value("${env}")
  String environment;

  @Value("${instanceId}")
  String instanceId;

  @Bean
  MeterRegistryCustomizer<PrometheusMeterRegistry> configureMetricsRegistry() {
    return registry -> registry.config()
      .commonTags("appName", appName, 
                  "env", environment, 
                   "instanceId", instanceId);
  }
}

@TimedAspect Anotasyonu

Örnek

Şöyle yaparız

import org.springframework.boot.actuate.autoconfigure.metrics.MeterRegistryCustomizer;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import io.micrometer.core.aop.TimedAspect;
import io.micrometer.core.instrument.MeterRegistry;

@Configuration
public class RegistryConfig {
  @Bean
  MeterRegistryCustomizer<MeterRegistry> metricsCommonTags() {
    return registry -> registry.config().commonTags("region", "someRegionName");
  }
  
  @Bean
  TimedAspect timedAspect(MeterRegistry registry) {
    return new TimedAspect(registry);
  }
}

@Timed Anotasyonu

Açıklaması şöyle

The quickest and easiest way to instrument REST controllers is to use the @Timed annotation on the controller or on individual methods of the controller. @Timed automatically adds these tags to the timer: exception, method, outcome, status, uri. It is also possible to supply additional tags to the @Timed annotation.

extraTags Alanı

Örnek

Şöyle yaparız

import io.micrometer.annotation.Timed;

@Slf4j
@RestController
public class DemoController {
  @GetMapping("/push-log")
  @ResponseStatus(HttpStatus.NO_CONTENT)
  @Timed(extraTags = {"demo-tag", "test-val"})
  public void pushLog() {
    log.debug("...");
  }
}

percentiles Alanı

Açıklaması şöyle

The '@Timed' annotation tells mirometer to record the percentiles of the method run times.

Şöyle yaparız

@Scheduled(cron = "0 10 2 ? * ?")
@SchedulerLock(name = "coinbase_avg_scheduledTask", 
        lockAtLeastFor = "PT1M", lockAtMostFor = "PT23H")
@Timed(value = "create.cb.avg", percentiles = { 0.5, 0.95, 0.99 })
public void createCbHAvg() {
  this.coinbaseService.createCbAvg();
}

MeterRegistry Sınıfı

Şu satırı dahil ederiz

import io.micrometer.core.instrument.MeterRegistry;

counter metodu - Sayaç

Counter nesnesi döndürür.

gauge metodu

gauge().set() şeklinde kullanılır

Örnek

Şöyle yaparız

@Component
public class Scheduler {

  private final AtomicInteger testGauge;
  private final Counter testCounter;

  public Scheduler(MeterRegistry meterRegistry) {
    testGauge = meterRegistry.gauge("custom_gauge", new AtomicInteger(0));
    testCounter = meterRegistry.counter("custom_counter");
  }

  @Scheduled(fixedRateString = "1000", initialDelayString = "0")
  public void schedulingTask() {
    testGauge.set(Scheduler.getRandomNumberInRange(0, 100));

    testCounter.increment();
  }

  private static int getRandomNumberInRange(int min, int max) {
    if (min >= max) {
      throw new IllegalArgumentException("max must be greater than min");
    }

    Random r = new Random();
    return r.nextInt((max - min) + 1) + min;
  }
}

Counter Sınıfı

Şu satırı dahil ederiz

import io.micrometer.core.instrument.Counter;

increment metodu

Örnek

Şöyle yaparız

import io.micrometer.core.instrument.MeterRegistry;

@RestController
@RequestMapping("/")
public class PrometheusSpringBoot {

  private final MeterRegistry meterRegistry;

  public PrometheusSpringBoot(MeterRegistry meterRegistry) {
    this.meterRegistry = meterRegistry;
  }

  @GetMapping("/2xx")
  public String simulate2xxResponse() {
    meterRegistry.counter("orders.2xx","status","OK").increment();
    return "...";
  }

  @GetMapping("/5xx")
  public String simulate5xxResponse() {
    meterRegistry.counter("orders.5xx","status","NOTOK").increment();
    return "...";
  }
	
  @PostMapping("/alert-hook")
  public void receiveAlertHook(@RequestBody Map request) throws Exception {
    System.out.println(request);
  }
}

Örnek

Şöyle yaparız

import io.micrometer.core.instrument.MeterRegistry;

@GetMapping("/2xx")
public String simulate2xxResponse() {
  meterRegistry.counter("orders.2xx","status","OK").increment();
  return "Got 2xx Response";
}

Örnek

Şöyle yaparız

import io.micrometer.core.instrument.Counter;
import io.micrometer.core.instrument.MeterRegistry;
import java.util.Random;
import java.util.concurrent.atomic.AtomicInteger;
import org.springframework.scheduling.annotation.Scheduled;
import org.springframework.stereotype.Component;

@Component
public class Scheduler {

  private final AtomicInteger testGauge;
  private final Counter testCounter;

  public Scheduler(MeterRegistry meterRegistry) {
    testGauge = meterRegistry.gauge("custom_gauge", new AtomicInteger(0));
    testCounter = meterRegistry.counter("custom_counter");
  }

  @Scheduled(fixedDelay=1000) // delay per 1 seconds
  public void schedulingTask() {
    testGauge.set(Scheduler.getRandomNumberInRange(0, 100));

    testCounter.increment();
  }

  private static int getRandomNumberInRange(int min, int max) {
    if (min >= max) {
      throw new IllegalArgumentException("max must be greater than min");
    }

    Random r = new Random();
    return r.nextInt((max - min) + 1) + min;
  }
}