Getting version upgrade advise to upgrade a BOM..

[Niels Basjes]

Hi,

I see quite a few situations where the dependencies for toolkit are
provided in the form of a dependency you must "import" in
the dependencyManagement section.
They provide this to ensure you always have a working combination for a lot
of closely related dependencies.

To illustrate the problem I ran into I created this minimal pom.xml:

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0";
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance";
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0
http://maven.apache.org/xsd/maven-4.0.0.xsd";>
    <modelVersion>4.0.0</modelVersion>

    <groupId>nl.basjes.example</groupId>
    <artifactId>dependency-version-test</artifactId>
    <version>0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <dependencyManagement>
        <dependencies>
            <dependency>
                <!-- This is the way we get a consistent set of versions of
the Google tools -->
                <groupId>com.google.cloud</groupId>
                <artifactId>libraries-bom</artifactId>
                <version>19.0.0</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>

    <dependencies>
        <dependency>
            <groupId>com.google.cloud</groupId>
            <artifactId>google-cloud-pubsub</artifactId>
        </dependency>
    </dependencies>
</project>


Now for this example the 19.0.0 is a valid version and absolutely not the
latest version.
What I'm looking for is a command that will give me the advice to update
the 19.0.0 to whatever is currently the latest version.
If I put this in an empty directory and try to get insight in what I need
to upgrade I do this:

mvn versions:display-dependency-updates


The output I get from this is the full list of all underlying dependencies
for which an update is available; yet no mention of the libraries-bom that
is in need of an update.

What I would like is a list of the things for which an update is available;
yet here I effectively want the opposite of what I get from this plugin: I
only want (should?) get the suggestion to update the libraries-bom and not
the full list of the versions defined in there.

Is there a way to achieve this?

--
Best regards / Met vriendelijke groeten,

Niels Basjes