###parent-checker-maven-plugin

Plugin to force for parent POM updates for using projects.

After release and having the using projects upgrade to the new version of their parent POM is always a burden. You have to send an email to the developers of the projects requesting an upgrade on the parent POM but the mail simply does not reach it's destination, goes to junk or simply no one cares about it :)

As developers we use the same build tool (maven) and so we can also use the same tool to pass the communiqué.

By default the plugin attaches itself to validate life-cycle phase to check parent POM updates if the user did not explicitly specify an execution in the plugin configuration. The plugin simply

• Checks whether the current building project has a parent POM
• If so, checks whether it is one of the parent POMs that we care (according to the given checkArtifacts config)
• If so, checks whether there is a newer version
• If so, depending on the plugin configuration, it makes the build fail or print a warning message to let the developer be aware of it

###Configuration

:::xml
<plugin>
    <groupId>org.hoydaa.maven.plugins</groupId>
    <artifactId>parent-checker-maven-plugin</artifactId>
    <version>1.0-SNAPSHOT</version>
    <!--<executions>
        <execution>
            <goals>
                <goal>check</goal>
            </goals>
        </execution>
    </executions>-->
    <configuration>
        <!-- If true makes the build fail when there is a newer version for the parent POM -->
        <forceUpgrade>false</forceUpgrade>
        <!-- The parent POM artifacts to check for update, you can make the plugin check for more than one parent POM -->
        <checkArtifacts>
            <artifact>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-parent-checker-plugin-parent</artifactId>
            </artifact>
        </checkArtifacts>
    </configuration>
</plugin>

####Options

• forceUpgrade: If true, makes the plugin fail when a newer version for the parent POM is available either in the local repository or in one of the remote repositories.
• checkArtifacts: Set the parent POM artifacts that you want to be checked by the plugin. You can set more than one.

Another option to make the build fail is to have a property named force.upgrade within the released parent POM. In this case no matter what is configured in the plugin configuration --regarding forceUpgrade--, if the plugin finds force.upgrade=true within any released POM file it will make the build fail since it is assumed that you have a SPECIFIC VERSION that you want to force for update. So if you want a specific version to force for update, just add a property named force.upgrade in it before releasing like the following example.

:::xml
<project>
....
    <properties>
        <force.upgrade>true</force.upgrade>
        ....
    </properties>
....
</project>

###Usage

As said, the plugin attaches itself to the validate life-cycle phase, meaning; it is enough that you define the plugin within your parent POM. But you can also run the plugin explicitly by executing the following line.

mvn org.hoydaa.maven.plugins:parent-checker-maven-plugin:check

Or you can define org.hoydaa.maven.plugins as a pluginGroup in your local maven settings.xml and use the plugin prefix to run it which is less verbose.

:::xml
<pluginGroups>
    <pluginGroup>org.hoydaa.maven.plugins</pluginGroup>
</pluginGroups>

In this case you just have to use the plugin prefix and the goal to run it, no groupId or artifactId is needed.

mvn parent-checker:check

###Outputs

Depending on the situation the plugin behaves differently and produces different outputs.

When the plugin is configured with force.upgrade=false and there are two new versions, it just displays a warning log.

[WARNING] New versions available for your parent POM org.hoydaa.maven.plugins:test-parent:pom:1.1!
[WARNING] 1.2 (not forced)
[WARNING] 1.3 (not forced)
[WARNING] Your parent POM org.hoydaa.maven.plugins:test-parent:pom:1.1 is 2 versions behind, you have to upgrade it to 1.3!

When the plugin is configured with force.upgrade=true and there are two new versions, it makes the build fail.

[WARNING] New versions available for your parent POM org.hoydaa.maven.plugins:test-parent:pom:1.1!
[WARNING] 1.2 (not forced)
[WARNING] 1.3 (not forced)
[INFO] ------------------------------------------------------------------------
[ERROR] BUILD ERROR
[INFO] ------------------------------------------------------------------------
[INFO] Your parent POM org.hoydaa.maven.plugins:test-parent:pom:1.1 is 2 versions behind, you have to upgrade it to 1.3!

When there are three versions one of which is forced (meaning there is a property force.upgrade=true within the released parent POM, it makes the build fail even the forceUpgrade is false for the plugin.

[WARNING] New versions available for your parent POM org.hoydaa.maven.plugins:test-parent:pom:1.1!
[WARNING] 1.2 (not forced)
[WARNING] 1.3 (not forced)
[WARNING] 1.4 (FORCED)
[INFO] ------------------------------------------------------------------------
[ERROR] BUILD ERROR
[INFO] ------------------------------------------------------------------------
[INFO] Your parent POM org.hoydaa.maven.plugins:test-parent:pom:1.1 is 3 versions behind, you have to upgrade it to 1.4! You have to upgrade your parent POM to the latest forced update at least!