JMX Service for Moleculer

A Moleculer Service that bridges a local or remote JMX registry into the Moleculer for Java framework. With it, any node in the cluster — including Node.js nodes — can query Java-specific runtime data (JVM memory usage, thread counts, and the low-level statistics exposed by servers such as Cassandra, Apache Kafka, or Elasticsearch). The service can also watch MBean attributes and broadcast a Moleculer event whenever a value changes, so any subscribed node is notified.

Documentation

Download

<dependency>
    <groupId>com.github.berkesa</groupId>
    <artifactId>moleculer-java-jmx</artifactId>
    <version>2.0.0</version>
</dependency>

Quick start

Add the service to a broker and call its actions (here over the local platform MBean server):

ServiceBroker broker = new ServiceBroker("node-1");
broker.createService(new JmxService());   // exposes jmx.* actions
broker.start();

// e.g. list MBean ObjectNames, or read one attribute
broker.call("jmx.listObjectNames");
broker.call("jmx.getAttribute",
    new Tree().put("objectName", "java.lang:type=Memory").put("attribute", "HeapMemoryUsage"));

The same jmx.* actions are callable remotely from any other node in the cluster.

Requirements

Java 17 or newer.

License

JMX Service for Moleculer is available under the MIT license.