prometheus-client-webapp

A simple WAR wrapper for instrumenting your app server and exposing metrics.

This is an alternative to the usually preferred jmx_exporter and suitable when you have minimal access to your app server, e.g. in a large centrally managed setup splitting operations and development responsiblities.

The WAR

• registers JVM DefaultExports
• registers JmxCollector
• exposes metrics via MetricsServlet

Configuration

You can configure the JmxCollector

1. by setting system property jmx_collector_config_file pointing to a local file
2. by setting in your web.xml a context parameter pointing to a local file

   <context-param>
        <param-name>jmx_collector_config_file</param-name>
        <param-value>/PATH/TO/CONFIGFILE</param-value>
    </context-param>
   

3. by setting the default config directly in the web.xml (default config!)

    <context-param>
        <param-name>jmx_collector_config</param-name>
        <param-value>
            ---
            # Default config embedded in web.xml
            rules:
            - pattern: ".*"
        </param-value>
    </context-param>
   

This last setting is the default config. First configuration found wins. So you can always override via system property.

Metrics

Metric names	Type	Descriptions
prometheus_webapp_build_info{version, buildTime, buildScmVersion, buildScmBranch}	Info	Build info of this WAR
jvm_*		Default JVM metrics, see Prometheus client hotpot
jmx_*		Default JMX Collector metrics, see Prometheus jmx_exporter

Building

mvn clean install

A simple test run

mvn jetty:run
open http://localhost:8080/

Requirements

For building:

• JDK 8
• Maven 3.6.x