Maven Release Plugin use in Jenkins Pipeline

Question

I'm using Jenkins Pipeline to automatically build and deploy my Java apps. I also use maven-release-plugin to perform Maven deploy to Artifactory.

The problem is my Jenkinsfile (or Jenkins Pipeline Configuration) :

1. We commit a version 0.1.00-SNAPSHOT on release branch
2. Jenkins Pipeline get the code, and perform maven release
3. Maven Release changes the version to 0.1.00
4. Maven Release tags GIT branch, commit and deploy the artifact
5. Maven Release changes the version to 0.2.00-SNAPSHOT and commit
6. Jenkins Pipeline detect a change in GIT, so triggers a new build

You understood that the last step creates an infinite loop, even if there is no useful commit.

Here is the interesting part of my Jenkinsfile :

sshagent([git_credential]) {
    sh "${maven_bin} --settings ${maven_settings} -DreleaseVersion=${release_version} -DdevelopmentVersion=${development_version} release:prepare release:perform -B"
}

How can I break the loop (avoid Jenkins to trigger new build when Maven commits on GIT)?

Thanks

Answer 1

IMHO with the advent of git and pull requests, I don't think using maven-release-plugin or maven-version-plugin with a Jenkins pipeline is a good idea.

Using Multibranch Pipeline with the versioning technique mentioned here is more in line with continuous delivery: https://axelfontaine.com/blog/dead-burried.html

Using the versioning technique above, the pom.xml now looks like this:

<project>
    ...
    <version>${revision}</version>

    <properties>
        <!-- Sane default when no revision property is passed in from the commandline -->
        <revision>0-SNAPSHOT</revision>
    </properties>

    <scm>
        <connection>scm:git:your-git-repo-url</connection>
    </scm>

    <distributionManagement>
        <repository>
            <id>artifact-repository</id>
            <url>your-artifact-repo-url</url>
        </repository>
    </distributionManagement>

    <build>
        <plugins>
            <plugin>
                <artifactId>maven-scm-plugin</artifactId>
                <version>1.9.5</version>
                <configuration>
                   <tag>${project.artifactId}-${project.version}</tag>
                </configuration>
            </plugin>
        </plugins>
    </build>
    ...
</project>

You can now produce releases on your Jenkins server very easily by configuring a Multibranch Pipeline with a Jenkinsfile to build on all branches and deploy only from master branch:

pipeline {
  agent any
  environment {
    REVISION = "0.0.${env.BUILD_ID}"
  }
  triggers {
    pollSCM('')
  }
  options {
    disableConcurrentBuilds()
    buildDiscarder(logRotator(numToKeepStr: '30'))
  }
  tools {
    maven '3.5.2'
    jdk 'jdk8'
  }
  stages {
    stage ('Initialize') {
      steps {
        sh '''
          echo "PATH = ${PATH}"
          echo "M2_HOME = ${M2_HOME}"
        '''
      }
    }
    stage ('Build') {
      steps {
        sh 'mvn clean package'
      }
    }
    stage ('Deploy') {
      when {
        branch 'master'
      }
      steps {
        script {
          currentBuild.displayName = "${REVISION}"
        }
        sh 'mvn deploy scm:tag -Drevision=${REVISION}'
      }
    }
  }
} 

See https://jenkins.io/blog/2017/02/07/declarative-maven-project/#set-up on how to configure a Multibranch Pipeline.

With this technique you develop only on non-master branches. Then create a pull request to merge your changes back to master branch. This should then deploy your artifact automatically to your artifact repository.

---

Addendum

When publishing to a Maven repository using the above method, the pom.xml will not have the proper version. To get Maven to publish the proper version, use the flatten-maven-plugin: http://www.mojohaus.org/flatten-maven-plugin/usage.html.

Also, check out: https://maven.apache.org/maven-ci-friendly.html