Extend annotation io.micrometer.core.annotation.Timed

I'm using @Timed in Spring Boot app for collecting metrics from methods and it works:

@Timed(percentiles = {0.95, 0.99}, histogram = true, extraTags = {"slice", "client"})

Since I'm using this annotation in the different places I decided to create custom annotation TimedExtended:

import io.micrometer.core.annotation.Timed;

import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

@Target({ElementType.METHOD, ElementType.TYPE})
@Retention(RetentionPolicy.RUNTIME)
@Timed(percentiles = {0.95, 0.99}, histogram = true, extraTags = {"slice", "client"})
public @interface TimedExtended {
}

But this new one doesn't work, metrics are not being sent to Influx. Do you have idea what should be done for fixing it?

Solution

If you’re using a custom annotation that wraps @Timed (a meta-annotation), such as @TimedExtended, the pointcut from io.micrometer.core.aop.TimedAspect "execution (@io.micrometer.core.annotation.Timed * .(..))" won't match it directly. This is because the execution expression looks only for methods explicitly annotated with @Timed, and it won’t recognise methods annotated with @TimedExtended.

For solving this problem I created my own Aspect, took as a base io.micrometer.core.aop.TimedAspect:

@Aspect
public class TimedExtendedAspect {
...
  @Around("execution (@com.test.metrics.TimedExtended * *.*(..))")
  @Nullable
  public Object timedMethod(ProceedingJoinPoint pjp) throws Throwable {
    if (shouldSkip.test(pjp)) {
      return pjp.proceed();
    }

    Method method = ((MethodSignature) pjp.getSignature()).getMethod();
    TimedExtended timed = method.getAnnotation(TimedExtended.class);
    if (timed == null) {
      method = pjp.getTarget().getClass().getMethod(method.getName(), method.getParameterTypes());
      timed = method.getAnnotation(TimedExtended.class);
    }

    return perform(pjp, timed, method);
  }
...
}

Also I modified my annotation in the next way:

import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

@Target({ElementType.METHOD, ElementType.TYPE})
@Retention(RetentionPolicy.RUNTIME)
public @interface TimedExtended {

  String value() default "";

  boolean longTask() default false;

  String description() default "";

  String[] extraTags() default {"slice", "client"};

  boolean histogram() default true;

  double[] percentiles() default {0.95, 0.99};
}

Last step - create bean for new Aspect:

@Bean
    TimedExtendedAspect timedExtendedAspect(InfluxMeterRegistry influxMeterRegistry) {
        return new TimedExtendedAspect(influxMeterRegistry);
    }