[FIXED] Configure distribution statistic for http.server.requests in spring-boot

Issue

Is there a way to configure distribution statistic expiry and buffer length for http.server.requests metrics?

I need to increase the expiry and couldn't find the proper way of doing this with spring boot actuator. Is it possible to configure these settings?

Solution

You should look at DistributionStatisticConfig. The creation of DEFAULT instance shows how to set expiry and bufferLength.

All you have to do in Spring Boot is register a bean MeterRegistryCustomizer in your @SpringBootApplication or @Configuration class.

import org.springframework.boot.actuate.autoconfigure.metrics.MeterRegistryCustomizer;

@Bean
public MeterRegistryCustomizer<MeterRegistry> metricsCommonTags() {
    return registry -> registry.config()
        .commonTags("myTag", myTagValue)
        .meterFilter(new MeterFilter() {

            @Override
            public DistributionStatisticConfig configure(Meter.Id id,
                                                         DistributionStatisticConfig config) {
                if (id.getName().startsWith("http.server.requests")) {
                    return config.merge(DistributionStatisticConfig.builder()
                        .percentilesHistogram(true)
                        .percentiles(0.5, 0.9, 0.99)
                        .percentilePrecision(1)
                        .minimumExpectedValue(1L)
                        .maximumExpectedValue(Long.MAX_VALUE)
                        .expiry(Duration.ofMinutes(1))
                        .bufferLength(2)
                        .build());
                }
                return config;
            }
        });
}

You can also ask on Micrometer's Slack channel.

Answered By - lu_ko
Answer Checked By - Cary Denson (JavaFixing Admin)