Build only affected modules in Jenkins / Maven

Question

We are using Git, Jenkins and Artifactory as CI/CD pipeline. We have a large code base and each time the full build takes a lot of time to process. For example, we have a aggregated pom project containing 100+ modules. The parent pom.xml file looks like the following:

<project>
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.sample</groupId>
    <artifactId>project</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>pom</packaging>

    <modules>
        <module>module-1</module>
        <module>module-2</module>
        <module>module-n</module>
    </modules>
</project>

We use this structure because some modules depend on some others. Also, we want to centralize the common dependencies, dependenciesManagement & pluginManagement in this parent pom file instead of maintaining 100+ pom files per module.

Because changes may not happen on every modules, we want to speed up the build process by only building the affected modules since last successful build. This can be done by maven.

Example: mvn clean install -pl module1,module2,module3 -amd -am

It is easy if the developer knows what modules has been changed. If not, some maven plugin can help the developer to detect the uncommitted changes compared with git repository. Or some people may do mvn install -amd -pl $(git status | grep -E "modified:|deleted:|added:" | awk '{print $2}' | cut -f1 -d"/")

But these solutions do not fit to our Jenkins pipeline. The Jenkins server always pull the latest version of the project from git and start the build. I don't know if Jenkins has the capability to detect what modules has been changed from git history and from its build history (any state info?). Besides, we are running multiple Jenkins slaves process. The build job is not always stick to the same machine workspace.

I searched one Jenkins plugin seem can solve my problem. https://wiki.jenkins.io/display/JENKINS/Maven+Project+Plugin

I tried to install a fresh latest version of Jenkins with this plugin but still unable to find the feature "Incremental build - only build changed modules".

Could somebody suggest some ways (by plugin or manuel scripting) to help to build only changed modules in Jenkins? I have been searching for many days and still could not find a workable solution. I would be very grateful if somebody could give me some insight or direction how we should do it. Thanks a lot!

Answer 1

I know this is an old question but if anyone is still looking for an answer, I created a Jenkinsfile for a Multi Branch Pipeline which builds affected modules only for a maven multi-module project.

Jenkinsfile