Spring Actuator Metrics preserve "dot" in tags

Question

I'm creating tags in my metrics exporter, in this way:

  metrics:
    export:
      elastic:
        host: "xx"
        index: "metricbeat-k8s-apps"
        user-name: "elastic"
        password: "xx"
        step: 30s
        connect-timeout: 10s
    tags:
      cluster: ${CLUSTER}
      kubernetes.pod.name: ${POD_NAME}
      kubernetes.namespace: ${POD_NAMESPACE}

But I don't know why "kubernetes.pod.name" is converted to "kubernetes_pod_name", how can I preserve the dots ?

Answer 1

The word separator in Micrometer is 'dot' (see docs), according to the Elastic naming conventions, the word separator is 'underscore' in Elastic. In Micrometer, every registry has a NamingConvention. For Elastic, it is ElasticNamingConvention.

As you can see in that class, the default naming convention is snake_case:

public ElasticNamingConvention() {
    this(NamingConvention.snakeCase);
}

You can see how ElasticMeterRegistry uses this naming convention, but you can provide your own, please check the docs.