Building OSGi Node

As noted previously, OSGi-enabled OSH nodes enable dynamic module installation. When an OSGi-enabled OSH node is built, it can be configured with several bundle repositories from which additional modules can be installed.

OSH Core OSGi Build

Within osh-core, the included Gradle build script will build an OSGi-enabled OSH node, that links to an example/test GeoRobotix bundle repository.

In order to build this node, we can move to a local osh-core repository and run the build script.

info

osh-node-dev-template includes osh-core as a submodule under /include/osh-core. Or, you may directly clone osh-core somewhere else using:

git clone https://github.com/opensensorhub/osh-core.git

Building osh-core:

/osh-core

./gradlew build -x test

This results in the build of a normal OSH node, and an OSGi-enabled OSH node.

We can navigate to the osh-core/build/distributions directory to see these two nodes.

/osh-core

cd build/distributions/
ls

This will show us osh-core-2.0-beta2.zip and osh-core-osgi-2.0-beta2.zip.

We can unzip osh-core-osgi-2.0-beta2.zip and inspect the config.json and launch scripts.

/osh-core/build/distributions

unzip osh-core-osgi-2.0-beta2.zip
cd osh-core-osgi-2.0-beta2/

We can see from the OSGi node's config.json, that it comes with an example/test bundle repository.

/osh-core/build/distributions/osh-core-osgi-2.0-beta2/config.json

[
  {
    "objClass": "org.sensorhub.impl.service.HttpServerConfig",
    "id": "6ca9c8a8-9768-4b60-9554-a8d277bf6b3f",
    "name": "HTTP Server",
    "moduleClass": "org.sensorhub.impl.service.HttpServer",
    "httpPort": 8181,
    "servletsRootUrl": "/sensorhub",
    "staticDocsRootDir": "web",
    "autoStart": true
  },
  {
    "objClass": "org.sensorhub.ui.AdminUIConfig",
    "id": "7219eb9f-b591-4c2c-9ad9-4b63a29a1c4a",
    "moduleClass": "org.sensorhub.ui.AdminUIModule",
    "bundleRepoUrls": [
      "https://cloud.georobotix.io/addons/index.xml"
    ],
    "autoStart": true
  }
]

We can also see that the launch scripts are different from normal OSH nodes' launch scripts, as they use SensorHubOsgi as an entrypoint, instead of SensorHub.

/osh-core/build/distributions/osh-core-osgi-2.0-beta2/launch.sh

#!/bin/bash
java 
-Xmx256m 
-Dlogback.configurationFile=./logback.xml 
-cp "lib/*" 
org.sensorhub.impl.osgi.SensorHubOsgi config.json