Maven Git Versioning Extension

ℹ Also available as Gradle Plugin

This extension can virtually set project version and properties, based on current Git status.

ℹ No POM files will be modified, version and properties are modified in memory only.

• Get rid of...
  • editing pom.xml
  • managing project versions with within files and Git tags.
  • Git merge conflicts.
• Highly customizable configuration, see example below.

Usage

⚠️ minimal required maven version is 3.6.3

Add Extension to Maven Project

create or update ${rootProjectDir}/.mvn/extensions.xml file

<extensions xmlns="http://maven.apache.org/EXTENSIONS/1.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/EXTENSIONS/1.0.0 https://maven.apache.org/xsd/core-extensions-1.0.0.xsd">

    <extension>
        <groupId>me.qoomon</groupId>
        <artifactId>maven-git-versioning-extension</artifactId>
        <version>6.3.0</version>
    </extension>

</extensions>

ℹ Consider CI/CD section when running this extension in a CI/CD environment

Configure Extension

You can configure the final version format for specific branches and tags separately.

Create ${rootProjectDir}/.mvn/maven-git-versioning-extension.xml.

Example: maven-git-versioning-extension.xml

<gitVersioning>
    <branch>
        <pattern>main</pattern>
        <versionFormat>${version}</versionFormat>
    </branch>
    <branch>
         <pattern>feature/(.+)></pattern>
         <versionFormat>${1}-SNAPSHOT</versionFormat>
     </branch>
    <tag>
        <pattern>v([0-9].*)></pattern>
        <versionFormat>${1}</versionFormat>
    </tag>
</gitVersioning>

• optional <disable> global disable(true)/enable(false) extension.

  • Can be overridden by command option, see (Parameters & Environment Variables)[#parameters-&-environment-variables].

• optional <updatePom> global enable(true)/disable(false) version and properties update in original pom file.

  • Can be overridden by command option, see (Parameters & Environment Variables)[#parameters-&-environment-variables].

• optional <preferTags> global enable(true)/disable(false) prefer tag rules over branch rules if both match.

• <branch> specific version format definition.

  • <pattern> An arbitrary regex to match branch names (has to be a full match pattern e.g. feature/.+ )
  • <versionFormat> An arbitrary string, see Version Format & Placeholders
  • <property> A property definition to update the value of a property
    • <name> The property name
    • <valueFormat> The new value format of the property, see Version Format & Placeholders
  • optional <updatePom> Enable(true) or disable(false) version and properties update in original pom fill (will override global <updatePom> value)
  • ⚠ considered if...
    • HEAD attached to a branch git checkout <BRANCH>
      
    • Or branch name is provided by environment variable or command line parameter

• <tag> specific version format definition.

  • <pattern> An arbitrary regex to match tag names (has to be a full match pattern e.g. v[0-9].* )
  • <versionFormat> An arbitrary string, see Version Format & Placeholders
  • <property> A property definition to update the value of a property
    • <name> The property name
    • <valueFormat> The new value format of the property, see Version Format & Placeholders
  • optional <updatePom> Enable(true) or disable(false) version update in original pom fill (will override global <updatePom> value)
  • ⚠ considered if...
    • HEAD is detached git checkout <TAG>
      
    • Or tag name is provided by environment variable or command line parameter

• <commit> specific version format definition.

  • <versionFormat> An arbitrary string, see Version Format & Placeholders
  • <property> A property definition to update the value of a property
    • <name> The property name
    • <valueFormat> The new value format of the property, see Version Format & Placeholders
  • ⚠ considered if...
    • HEAD is detached git checkout <COMMIT> and no matching version tag is pointing to HEAD
      

Format Placeholders

ℹ whole versionFormat will be slugified automatically, that means all / characters replaced by -

ℹ define placeholder default value (placeholder is not defined) like this ${name:-default_value}
e.g ${buildNumber:-0} or ${buildNumber:-local}

ℹ define placeholder overwrite value (placeholder is defined) like this ${name:+overwrite_value}
e.g ${dirty:-SNAPSHOT} resolves to -SNAPSHOT instead of -DIRTY

• ${ref}

  • current ref name (branch name, tag name or commit hash)

• ${ref.slug}

  • like ${ref} with all / replaced by -

• ${branch} (only available within branch configuration)

  • The branch name of HEAD
  • e.g. 'master', 'feature/next-big-thing', ...

• ${branch.slug}

  • like ${branch} with all / replaced by -

• ${tag} (only available within tag configuration)

  • The tag name that points at HEAD, if multiple tags point at HEAD latest version is selected
  • e.g. 'version/1.0.1', 'v1.2.3', ...

• ${tag.slug}

  • like ${tag} with all / replaced by -

• ${commit}

  • The HEAD commit hash
  • e.g. '0fc20459a8eceb2c4abb9bf0af45a6e8af17b94b'

• ${commit.short}

  • The short HEAD commit hash (7 characters)
  • e.g. '0fc2045'

• ${commit.timestamp}

  • The HEAD commit timestamp (epoch seconds)
  • e.g. '1560694278'

• ${commit.timestamp.year}

  • The HEAD commit year
  • e.g. '2021'

• ${commit.timestamp.month}

  • The HEAD commit month of year
  • e.g. '01'

• ${commit.timestamp.day}

  • The HEAD commit day of month
  • e.g. '01'

• ${commit.timestamp.hour}

  • The HEAD commit hour of day (24h)
  • e.g. '01'

• ${commit.timestamp.minute}

  • The HEAD commit minute of hour
  • e.g. '01'

• ${commit.timestamp.second}

  • The HEAD commit second of minute
  • e.g. '01'

• ${commit.timestamp.datetime}

  • The HEAD commit timestamp formatted as yyyyMMdd.HHmmss
  • e.g. '20190616.161442'

• Pattern Groups

  • Contents of group in the regex pattern can be addressed ${GROUP_NAME} or ${GROUP_INDEX}
  • ${GROUP_NAME.slug} or ${GROUP_INDEX.slug}
    • like ${GROUP_NAME} or ${GROUP_INDEX} with all / replaced by -
  • Examples
    • Named Group

      <branch>
          <pattern><![CDATA[feature/(?<feature>.+)]]></pattern>
          <versionFormat>${feature}-SNAPSHOT</versionFormat>
      </branch>
      

    • Group Index

      <tag>
          <pattern>v([0-9].*)'</pattern>
          <versionFormat>${1}</versionFormat>
      </tag>
      

• ${version}

  • version set in pom.xml
  • e.g. '1.0.0-SNAPSHOT'

• ${version.release}

  • like ${version} without -SNAPSHOT postfix
  • e.g. '1.0.0'

• ${dirty}

  • if repository has untracked files or uncommitted changes this placeholder will resolve to -DIRTY, otherwise it will resolve to an empty string.

• ${dirty.snapshot}

  • if repository has untracked files or uncommitted changes this placeholder will resolve to -SNAPSHOT, otherwise it will resolve to an empty string.

• ${value} - Only available within property format

  • value of matching property

• ${env.VARIABLE}

  • value of environment variable VARIABLE

Parameters & Environment Variables

• Disable Extension

  • Environment Variables
    • export VERSIONING_DISABLE=true
  • Command Line Parameters
    • mvn ... -Dversioning.disable=true

• Provide branch or tag name

  • Environment Variables
    • export VERSIONING_GIT_BRANCH=$PROVIDED_BRANCH_NAME
    • export VERSIONING_GIT_TAG=$PROVIDED_TAG_NAME
  • Command Line Parameters
    • mvn ... -Dgit.branch=$PROVIDED_BRANCH_NAME
    • mvn ... -Dgit.tag=$PROVIDED_TAG_NAME

  ℹ Especially useful for CI builds see Miscellaneous Hints

• Update pom.xml

  • Environment Variables
    • export VERSIONING_UPDATE_POM=true
  • Command Line Parameters
    • mvn ... -Dversioning.updatePom=true

• Prefer Tags for Versioning instead of Branches

  • Environment Variables
    • export VERSIONING_PREFER_TAGS=true
  • Command Line Parameters
    • mvn ... -Dversioning.preferTags=true

Provided Project Properties

• git.commit e.g. '0fc20459a8eceb2c4abb9bf0af45a6e8af17b94b'
• git.ref value of branch or tag name or commit hash
  • git.ref.slug like git.ref with all / replaced by -
• git.branch e.g. 'feature/next-big-thing', only set for branch versioning
  • git.branch.slug like git.branch with all / replaced by -
• git.tag e.g. 'v1.2.3', only set for tag versioning
  • git.tag.slug like git.tag with all / replaced by -
• git.commit.timestamp e.g. '1560694278'
• git.commit.timestamp.datetime e.g. '2019-11-16T14:37:10Z'
• git.dirty repository's dirty state indicator true or false

Miscellaneous Hints

Enable Debug/Trace Logging for extension

mvn ... -Dorg.slf4j.simpleLogger.log.me.qoomon.maven.gitversioning=debug

Commandline To Print Project Version

mvn help:evaluate -Dexpression=project.version -q -DforceStdout

Reproducible builds

The reproducible builds feature (https://maven.apache.org/guides/mini/guide-reproducible-builds.html) newly introduced in maven can be easily supported with this extension by using the latest commit timestamp as build timestamps.

<project.build.outputTimestamp>${git.commit.timestamp.datetime}</project.build.outputTimestamp>

IntelliJ Setup

For a flawless experience you need to disable this extension during project import. Disable it by adding -Dversioning.disable=true to Maven Importer VM options (Preferences > Build, Execution, Deployment > Build Tools > Maven > Importing > VM options for importer).

CI/CD Setup

Most CI/CD systems do checkouts in a detached HEAD state so no branch information is available, however they provide environment variables with this information. You can provide those, by using Parameters & Environment Variables. Below you'll find some setup example for common CI/CD systems.

GitHub Actions Setup

execute this snippet before running your mvn command

if  [[ "$GITHUB_REF" = refs/tags/* ]]; then
    export VERSIONING_GIT_TAG=${GITHUB_REF#refs/tags/};
elif [[ "$GITHUB_REF" = refs/heads/* ]]; then
    export VERSIONING_GIT_BRANCH=${GITHUB_REF#refs/heads/};
elif [[ "$GITHUB_REF" = refs/pull/*/merge ]]; then
    export VERSIONING_GIT_BRANCH=${GITHUB_REF#refs/pull/};
fi

GitLab CI Setup

execute this snippet before running your mvn command

before_script:
  - export VERSIONING_GIT_TAG=$CI_COMMIT_TAG;
    export VERSIONING_GIT_BRANCH=$CI_COMMIT_BRANCH;

Jenkins Setup

execute this snippet before running your mvn command

if [[ "$GIT_BRANCH" = origin/tags/* ]]; then
    export VERSIONING_GIT_TAG=${GIT_BRANCH#origin/tags/};
else 
    export VERSIONING_GIT_BRANCH=${GIT_BRANCH#origin/};
fi

Build

  - mvn install
  # run integration tests after install, 
  # integration tests will run with LATEST version of extension installed
  - mvn failsafe:integration-test