Blueprint XML file scanning with Gradle OSGI plugin

I'm investigating migrating an existing OSGI/blueprint project from Maven to Gradle. In Maven the maven-bundle-plugin plugin scans context XML files for imports that might not occur in the code, however I can't get this to work with the Gradle OSGI plugin.

For example, blueprint XML contains an import like this

<reference id="exampleService" availability="mandatory" interface="com.adamish.test.Test" />

Maven

Using the Bundle-Blueprint instruction in the POM with maven-bundle-plugin...

<plugin>
    <groupId>org.apache.felix</groupId>
    <artifactId>maven-bundle-plugin</artifactId>
    <version>2.4.0</version>
    <extensions>true</extensions>
    <configuration>
        <instructions>
        <Bundle-Blueprint>OSGI-INF/blueprint/context.xml</Bundle-Blueprint> 
        </instructions>
    </configuration>
</plugin>

Then the generated MANFEST.MF will contain an import like this

Import-Package: com.adamish.test

Gradle

However using the following build.gradle file does not generate a MANIFEST.MF with a Import-Package for com.adamish.test

apply plugin: 'osgi'

jar {
    manifest {
        instruction 'Bundle-Blueprint', 'OSGI-INF/blueprint/context.xml'
    }
}

Analysis

Both Maven and Gradle use BND which seems to contain the Bundle-Blueprint instruction, however when invoked via Gradle it does not cause imports to be added to the MANIFEST.

I've tested this in Gradle 2.4 and now latest 2.10

Solution

The Blueprint parsing capability of maven-bundle-plugin is provided by the class BlueprintPlugin part of maven-bundle-plugin, not BND. BND does contain some blueprint-aware code, however that is part of a repoindex command tool.

I've been able to workaround this issue temporarily by parsing the XML files manually and building list of Java packages

def importPackages = new LinkedHashSet<String>();
fileTree(dir: 'src/main/resources/OSGI-INF/blueprint/', include: '*.xml').each {
   new XmlSlurper().parse(it).'**'.findAll { it.@availability == "mandatory" }.each {
      def iFace = [email protected]()
      importPackages.add(iFace.substring(0, iFace.lastIndexOf('.')))
   }
}

importPackages.add('com.adamish.foo')

jar {
    manifest {
        instruction 'Import-Package', importPackages.join(',')
    }
}