micrometer-pekko-sample

This sample demonstrates how to add Micrometer-Pekko metrics to your application.

This sample is based on https://github.com/pjfanning/micrometer-akka-sample

Micrometer Metrics compares itself to SLF4J, but for metrics.

All you need to do is add a dependency on the micrometer-pekko jar, add some configuration to your application.conf and to enable aspectjweaver.

This sample uses micrometer-registry-prometheus to have the metrics registered as Prometheus client metrics. This is setup in Main.scala.

sbt clean run

This sample uses sbt-javaagent to enable aspectjweaver. This plugin basically adds this to the java runtime command.

-javaagent:/path/to/aspectjweaver-1.9.21.2.jar

If you want to use micrometer-pekko with your own application, ensure that you startup script adds something like this:

JAVA_AGENT="-javaagent:$BASE/lib/aspectjweaver-1.9.21.2.jar"
$JAVA_HOME/bin/java $JAVA_AGENT -cp $CP $JVM_OPTS $CLASS_NAME

To query the metrics endpoint, use:

curl http://localhost:12345/metrics

Running with Java 16 and above

Note that the build.sbt has this:

//uncomment this add-opens -- needed for Java 16 and above runtimes -- will cause issues if used with Java 8 runtime
run / javaOptions ++= Seq("--add-opens", "java.base/java.lang=ALL-UNNAMED")

If you use micrometer-pekko in your own application, you will need to add an equivalent --add-opens configuration.

Grafana

If you want to visualise the metrics, you could try Grafana. The Prometheus website has a page about setting up Prometheus Server to scrape your metrics and how to integrate this with Grafana.