Tracer Implementation

A demo project that shows how to implement a tracer for the Liberty mpOpentracing-3.0 feature. Once implemented as an OSGI bundle, a tracer can be included as a user feature that will automatically pull the mpOpentracing-3.0 feature.

Building this project relies on the bnd-process plugin to process the bnd.bnd file which will generate the MANIFEST.MF to be included in the project. Additionally, annotations found in the OpentracingZipkinTracerFactory.java provide information for the manifest. If you decide to roll your own tracer, then you'll need to ensure your factory implementation provides these annotations to correctly generate the manifest file.

opentracingZipkin

To compile and package, run:

mvn package

This will build target/liberty-opentracing-zipkintracer-3.0-sample.zip. Copy this file to ${wlp.user.dir} and unzip it to install the feature extension:

$ cp target/liberty-opentracing-zipkintracer-3.0-sample.zip ${WLP}/usr/
$ cd ${WLP}/usr/
$ unzip liberty-opentracing-zipkintracer-3.0-sample.zip
$ ls -R extension/
extension/:
lib

extension/lib:
com.ibm.ws.io.opentracing.zipkintracer-0.33.jar  features

extension/lib/features:
opentracingZipkin-0.33.mf

Enable the feature in server.xml:

<featureManager>
  [...]
  <feature>usr:opentracingZipkin-0.33</feature>
</featureManager>

Finally, enable the tracer with a configuration element (this defaults to a server at http://zipkin:9411/):

<opentracingZipkin />

Configuring the tracer

The opentracingZipkin element supports configuration of the zipkin server host and port, and detailed configuration of the zipkin builder and reporter. This support is provided by the Config class in OpentracingZipkinTracerFactory.java. The options are localized and described in detail in metatype.properties.

For example, to specify a different host and port:

<opentracingZipkin host="myhost.com" port="4433" />

Publishing to Maven Central

This project uses the Maven Central Portal for publishing releases. The publishing process uses manual review and approval for maximum control.

Quick Start

1. Deploy to Central Portal:

   mvn clean deploy -P central-release

2. Review and Publish:

   • Log in to https://central.sonatype.com/
   • Navigate to "Deployments"
   • Review your deployment
   • Click "Publish" to release to Maven Central

Prerequisites

• Maven Central Portal account with verified namespace
• User token configured in ~/.m2/settings.xml
• GPG key for signing artifacts

For detailed instructions, see MIGRATION.md.

Maven Dependency

Once published, users can include this tracer in their projects:

<dependency>
    <groupId>net.wasdev.wlp.tracer</groupId>
    <artifactId>liberty-opentracing-zipkintracer</artifactId>
    <version>3.0.2</version>
</dependency>

Available on Maven Central: https://central.sonatype.com/artifact/net.wasdev.wlp.tracer/liberty-opentracing-zipkintracer