How to set tag for Maven release

Question

I'm using the Maven Release Plugin and I'm trying to tag every release with my Jenkins build number.

I've tried this from pom.xml:

      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-release-plugin</artifactId>
        <version>2.5.3</version>
        <configuration>
          <tagNameFormat>${env.BUILD_NUMBER}</tagNameFormat>
        </configuration>
      </plugin>

And also from Jenkins when I'm calling Maven:

mvn release:prepare -tag=${env.BUILD_NUMBER}

However, I'm getting:

Unable to tag SCM
[ERROR] Provider message:
[ERROR] The git-tag command failed.
[ERROR] Command output:
[ERROR] fatal: tag 'my-project-1.3' already exists

I'm not sure what 1.3 stands for.

So how can I tag the release? I am doing any mistake?

Solution

Your pom is probably on version 1.3-SNAPSHOT

mvn release:prepare

Will update the version to 1.3, create the git tag "artifactid-version" in your case my-project-1.3, then set the version in your pom to 1.4-SNAPSHOT for the next iteration.

To fix your problem delete the tag see How to delete a git remote tag? then run mvn release:prepare again.

You may need to set your version back to 1.3-SNAPSHOT, this can be done with

mvn versions:set -DnewVersion=1.3-SNAPSHOT

Or just edit you pom/poms.

Comments

[bsky]

If I do mvn release:prepare multiple times, the version still remains 1.3 and isn't incremented. Any idea why?

[Essex Boy]

@octavian The version will be changed to 1.4-SNAPSHOT after the git tag, so it that command fails this will not happen.

[bsky]

Can I do something like mvn release:prepare -DnewVersion=${env.BUILD_NUMBER}, where BUILD_NUMBER is the build number from Jenkins? I would like to specify a version depending on the Jenkins build number but I don't know how.

[Essex Boy]

@octavian you are getting away from the idea of a "release" in maven terms. A release is intended to be done rarely, say at the end of a sprint, The version should be decided by the project. Perhaps you don't really want to do a release? Remember you still have all you git commits which you can go back to if needed. HTH.

[bsky]

In the end, I will not do a release for every build. I will do a release only in some cases. However, I would like to have the build number in the name as well.

[Essex Boy]

@octavian mvn:release:prepare will tag and update the version, mvn release:perform will install the released/tagged version in your repository (Nexus or similar). This is then an immutable binary artifact which is linked to a source code state by the git tag. Why do you need the build number? You can return the the source with a simple "git checkout my-project-1.3"