openHAB bundle for Prometheus metrics

Development with Eclipse IDE

• Setting up the openHAB IDE

https://www.openhab.org/docs/developer/development/ide.html#prerequisites

You should have your IDE almost the same as on picture (if you select all projects to import in bullet above):

We would suggest to import not all to increase local build process:

and plus 2 plugins at the bottom

• Import Kugu projects into IDE: File -> Open Projects From File System... Select projects and import Your IDE should be like here:

• Set active Target Open com.kuguhome.openhab.prometheusmetrics.targeteclipse.target file in Eclipse IDE Change locations of the bundles to the path on your local machine Save the file Click Reload Click Set as Active Target Platform

• Select Debug configuration Click Debug -> Debug Configuration and select all plugins on third tab which will be present after typing "prom" in textbox

Click Apply and Debug

• You should see the log in the console appeared after the build and non HTTP 404 status on page

http://localhost:8080/rest/metrics/prometheus

Production development with Maven

• Clean artifacts on root of project and create a repository for .target project

mvn clean
cd com.kuguhome.openhab.prometheusmetrics.p2site
mvn p2:site

• Run packaging

cd ../com.kuguhome.openhab.prometheusmetrics
mvn package

• Copy prometheus bundles and com.kuguhome.openhab.prometheusmetrics bundle into addon folder and start openHAB runtime

cp com.kuguhome.openhab.prometseusmetrics.target/bundles/simpleclient-0.4.0.jar ~/dev/openhab-2.3.0/addons/
cp com.kuguhome.openhab.prometseusmetrics.target/bundles/simpleclient_common-0.4.0.jar ~/dev/openhab-2.3.0/addons/
cp com.kuguhome.openhab.prometseusmetrics/target/com.kuguhome.openhab.prometheusmetrics-2.4.0-SNAPSHOT.jar ~/dev/openhab-2.3.0/addons/
cd ~/dev/openhab-2.3.0/
./start_debug.sh

• Also will be useful to remove cache of the runtime:

cd ~/dev/openhab-2.3.0/userdata/
rm -rf !(etc)

• You should see the log in the console appeared after and non HTTP 404 status on page

http://localhost:8080/rest/metrics/prometheus

Several files which you should consider:

startup.properties

• for loading bundles at startup from maven repo

org.ops4j.pax.logging.cfg

• for logging properties

• Add repository created with p2:site goal

Possible issues and problems

• Version absence

check your MANIFEST file for every artifact in the list and put appropriate version. Example:

ch.qos.logback.classic;version="1.0.7",

• Package sun.misc

We created separate bundle fragment to deal with this problem. Check if this fragment added to your Target

• Target file error You can face with such error during work with .target file:

We didn't resolve this problem so there is one way to return to stable environment - to select default .target file You can find it the project Infrastructure -> launch -> openhab.target Then here you can add bundle folder with necessary bundles

Resources

• Documentation of prometheus' data format https://prometheus.io/docs/concepts/metric_types/
• Developing Bindings https://www.eclipse.org/smarthome/documentation/development/bindings/how-to.html
• Java library for prometheus https://github.com/prometheus/client_java
• HABmin as a reference how to implement a UI https://github.com/openhab/org.openhab.ui.habmin