How to measure service methods using spring boot 2 and micrometer

Question

I started my first project on Spring Boot 2 (RC1). Thanks to the already good documentation this has not been to hard coming from Spring Boot 1.x.

However now that I

Answer 1

Here's a little sample which should get you going. There's more variants to Timer.record() which aren't shown here. (Also: Field injection only used for brevity.) You don't have to put the called methods name into a tag. You can also make it part of the metric name itself. Just wanted to show what you could do.

Update 2018-03-12: As of Micrometer 1.0.0 a TimedAspect has been introduced so that you can also use the @Timed annotation. For now you need to register the Bean yourself. (You need to be cautious though when you have custom @Timed annotations on your Spring-MVC or Jersey resources.) This was already mentioned by Michal Stepan in a follow-up answer.

package io.github.mweirauch.micrometered.eval;

import java.util.concurrent.TimeUnit;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.EnableAspectJAutoProxy;
import org.springframework.scheduling.annotation.Scheduled;
import org.springframework.stereotype.Service;

import io.micrometer.core.annotation.Timed;
import io.micrometer.core.aop.TimedAspect;
import io.micrometer.core.instrument.MeterRegistry;
import io.micrometer.core.instrument.Timer;
import io.micrometer.core.instrument.Timer.Sample;

@Configuration
@EnableAspectJAutoProxy
public class TimingStuff {

    @Service
    static class MyService {

        @Autowired
        private MeterRegistry registry;

        public void helloManual() {
            // you can keep a ref to this; ok to call multiple times, though
            Timer timer = Timer.builder("myservice").tag("method", "manual").register(registry);

            // manually do the timing calculation
            long start = System.nanoTime();
            doSomething();
            timer.record(System.nanoTime() - start, TimeUnit.NANOSECONDS);
        }

        public void helloSupplier() {
            Timer timer = Timer.builder("myservice").tag("method", "supplier").register(registry);

            // execution of the method is timed internally
            timer.record(() -> doSomething());
        }

        public void helloSample() {
            Timer timer = Timer.builder("myservice").tag("method", "sample").register(registry);

            // records time taken between Sample creation and registering the
            // stop() with the given Timer
            Sample sample = Timer.start(registry);
            doSomething();
            sample.stop(timer);
        }

        // TimedAspect adds "class" and "method" tags
        @Timed(value = "myservice.aspect")
        public void helloAspect() {
            doSomething();
        }

        private void doSomething() {
            try {
                Thread.sleep(50);
            } catch (InterruptedException e) {
                //
            }
        }

    }

    @Autowired
    private MyService myService;

    @Bean
    TimedAspect timedAspect(MeterRegistry registry) {
        return new TimedAspect(registry);
    }

    @Scheduled(fixedRate = 1000)
    public void postConstruct() {
        myService.helloManual();
        myService.helloSupplier();
        myService.helloSample();
        myService.helloAspect();
    }

}

In case you go for Prometheus, you'd end up with something like that:

# HELP myservice_seconds  
# TYPE myservice_seconds summary
myservice_seconds_count{application="micrometered",method="manual",} 4.0
myservice_seconds_sum{application="micrometered",method="manual",} 0.200378014
myservice_seconds_max{application="micrometered",method="manual",} 0.050115291
myservice_seconds_count{application="micrometered",method="supplier",} 4.0
myservice_seconds_sum{application="micrometered",method="supplier",} 0.200393455
myservice_seconds_max{application="micrometered",method="supplier",} 0.05011635
myservice_seconds_count{application="micrometered",method="sample",} 4.0
myservice_seconds_sum{application="micrometered",method="sample",} 0.200527005
myservice_seconds_max{application="micrometered",method="sample",} 0.050250191
# HELP myservice_aspect_seconds  
# TYPE myservice_aspect_seconds summary
myservice_aspect_seconds_count{application="micrometered",class="io.github.mweirauch.micrometered.eval.TimingStuff$MyService",method="helloAspect",} 4.0
myservice_aspect_seconds_sum{application="micrometered",class="io.github.mweirauch.micrometered.eval.TimingStuff$MyService",method="helloAspect",} 0.201824272
myservice_aspect_seconds_max{application="micrometered",class="io.github.mweirauch.micrometered.eval.TimingStuff$MyService",method="helloAspect",} 0.051014296