I am trying to use OSGI to allow me to use two different versions of a transitive dependency. The plan is that one version (the newer version) will be hidden away inside an OSGI bundle, the other will be on the runtime classpath as normal.
I have built the bundle jar using Gradle (with the Groovy DSL), but the problem is its associated runtime dependencies are wrong - it brings along the newer version, which is supposed to be hidden inside the bundle. This is still true when I do, in the build.gradle
file:
compileOnly deps.diffx
runtimeOnly(deps.diffx) {
exclude group: 'com.propensive', module: 'magnolia_' + versions.scala_v
}
If I examine the dependencies with the Gradle dependencies
task, it shows that magnolia is excluded from the runtimeOnly
configuration, as expected - but is not excluded from the runtimeClasspath
configuration.
If I then use ./gradlew dependencyInsight --dependency magnolia_2.12 --configuration runtime
to try to find out where this dependency is coming from, it tells me that the newer version is coming from runtimeClasspath
depending on diffx
, and this is selected via conflict resolution. Well thanks - I already knew that. The question is, why is my exclusion not being applied to the derived configuration?
Basically I want to do the opposite of this question.
I also tried constraint versions, but they exhibited the same problem:
compileOnly deps.diffx
runtimeOnly(deps.diffx) {
constraints {
implementation('com.propensive:magnolia_' + versions.scala_v + ':0.10.0') {
because 'this version is required by our other dependencies'
}
}
}
From the Gradle documentation:
On the upside, Gradle’s exclude handling is, in contrast to Maven, taking the whole dependency graph into account. So if there are multiple dependencies on a library, excludes are only exercised if all dependencies agree on them. For example, if we add opencsv as another dependency to our project above, which also depends on commons-beanutils, commons-collection is no longer excluded as opencsv itself does not exclude it.
So instead, we can use a dependency resolve rule:
def magnoliaVersion = '0.10.0'
configurations.runtimeClasspath {
resolutionStrategy.eachDependency { DependencyResolveDetails details ->
if (details.requested.group == 'com.propensive' && details.requested.name.startsWith("magnolia_") && details.requested.version != magnoliaVersion) {
details.useVersion magnoliaVersion
details.because 'this version is required by our other dependencies'
}
}
}
and then change the dependency back to a simple, single implementation
one:
implementation deps.diffx
Unfortunately, as the documentation notes, this resolve rule isn't published, so it has to be applied again in any dependent Gradle modules.