How to instrument Java application code metrics to Prometheus

Question

I am trying to export customized values metrics of my Java application to Prometheus. I have read that it could be done with Push Gateway, following an example I use the next method:

static void executeBatchJob() throws Exception {
     CollectorRegistry registry = new CollectorRegistry();
     Gauge duration = Gauge.build()
         .name("my_batch_job_duration_seconds").help("Duration of my batch job in seconds.").register(registry);
     Gauge.Timer durationTimer = duration.startTimer();
     try {
       // Your code here.
       myCode();
       // This is only added to the registry after success,
       // so that a previous success in the Pushgateway isn't overwritten on failure.
       Gauge lastSuccess = Gauge.build()
           .name("my_batch_job_last_success").help("Last time my batch job succeeded, in unixtime.").register(registry);
       lastSuccess.setToCurrentTime();
     } finally {
       durationTimer.setDuration();
       PushGateway pg = new PushGateway("172.16.124.40:9091");
       pg.pushAdd(registry, "my_batch_job");
     }
   }

But when I run the project I am having the next error: Exception in thread "main" java.lang.NoClassDefFoundError: io/prometheus/client/exporter/common/TextFormat at io.prometheus.client.exporter.PushGateway.doRequest(PushGateway.java:299) at io.prometheus.client.exporter.PushGateway.pushAdd(PushGateway.java:158) at nemshelloworld.NemsHelloWorld.executeBatchJob2(NemsHelloWorld.java:78) at nemshelloworld.NemsHelloWorld.main(NemsHelloWorld.java:33) Caused by: java.lang.ClassNotFoundException: io.prometheus.client.exporter.common.TextFormat at java.net.URLClassLoader.findClass(URLClassLoader.java:381) at java.lang.ClassLoader.loadClass(ClassLoader.java:424) at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:335) at java.lang.ClassLoader.loadClass(ClassLoader.java:357)

Answer 1

You're missing the simpleclient_common module, which is a listed dependency of simpleclient_pushgateway so it sounds like your pom.xml or equivalent isn't right.