The Maven auto releaser is a release engineering tool to automate the release process of Maven projects using Git as their Source Code Management tool and Gitlab CI for Continuous Integration builds.
This tool is composed of two parts:
- a creation step: a script to create release trigger branches on the repositories of the projects to release. This step is a one-shot action for a given repository.
- an execution runtime: a set of configuration, scripts and Continuous Integration files which will trigger the actual Maven release the classical way (i.e. with the maven-release-plugin or the unleash-maven-plugin). This execution runtime is used whenever a release is to be created on a given repository.
The main idea behind the release trigger branch concept is to create a Git branch on all repositories of the projects to release called the release trigger branch.
This branch will be composed of:
- a Continuous Integration configuration file (for Gitlab CI, it's the .gitlab-ci.yml). In this file, a trigger is set to be executed whenever a commit is pushed on the release trigger branch.
- a release.properties file with information on the next version to be released.
- an execution script, release.sh, called by the Continuous Integration trigger. It will execute the actual release Maven build.
- a README.md file with built-in help to guide end-users in the release process of their Maven projects
The content of release.sh file of the release trigger branch differs whether the remote mode or local mode is selected during the creation step.
The difference between the two modes are:
- in remote mode the creation step will only write links to the actual scripts which will be downloaded from this repository (https://github.com/debovema/maven-auto-releaser) by the execution runtime based on the version used during the creation step. Main advantage is that it is easy to update to the latest version of the Maven auto releaser tool by changing the version in the existing release trigger branches of your repositories.
- local mode will copy the content of scripts at their current version from this repository (https://github.com/debovema/maven-auto-releaser) during the creation step. Main advantage is that the repositories with release trigger branches does not rely on the Maven auto releaser tool once they have been initialized (especially if release environment has no access to the Internet). On the other hand, the Maven auto releaser tool becomes harder to update in this mode.
There are two properties file used by the Maven auto releaser: branch.properties and release.properties:
- branch.properties is used to provide parameters for the release trigger branch creation step. It is expected to be created in the same directory as the maven-auto-release.sh script.
- release.properties is used to provide parameters for the trigger and execution of releases. It is stored directly on the release trigger branch. To edit this file without triggering release, add the [ci skip] prefix in the commit message before pushing.
| Property | Description | Example (is default?) |
|---|---|---|
| DEV_VERSION | The next development version | 1.0.2-SNAPSHOT |
| RELEASE_VERSION | The next release version | 1.0.1 |
| GIT_USER_EMAIL | Value of git config user.email | john.doe@gmail.com |
| GIT_USER_NAME | Value of git config user.name | "John Doe" |
| INCREMENT_POLICY | The increment policy. Values can be: revision, minor, major | revision (yes) |
| MAVEN_RELEASER | The Maven plugin used to release Values can be: maven, unleash |
unleash (yes) |
| RELEASE_TRIGGER_BRANCH | The release trigger branch which initiates releases | release-trigger (yes) |
| SOURCE_BRANCH | The branch to checkout to initiate releases | master (yes) |
| UNLEASH_WORKFLOW_URL | (optional, if MAVEN_RELEASER == unleash) an URL to fetch the Maven unleash plugin workflow at runtime |
All properties of release.properties file can be set in branch.properties (except DEV_VERSION and RELEASE_VERSION). They will be forwarded to the release.properties during release trigger branch creation. In addition, these properties are also available specifically in creation step:
| Property | Description | Default value |
|---|---|---|
| DOCKER_IMAGE | The Docker image for Gitlab CI builds to be set in .gitlab-ci.yml | debovema/docker-mvn |
| MODE_SCRIPT_CONTENT | The mode for script content. Values can be: remote, local |
remote |
Currently, only Gitlab CI is supported, though adding other Continuous Integration tool based on configuration files should be easy.
- Gitlab & Gitlab CI installed
- Only Docker Gitlab runners are supported (at the moment)
- A Docker image with following packages installed: cUrl, Bash, Git, OpenSSH client, Java, Maven
- clone this repository
git clone https://github.com/debovema/maven-auto-releaser.git- enter into the directory
cd maven-auto-releaser- checkout the latest Git tag (= latest release) (or any version you want to use):
git checkout $(git describe --tags)-
edit the branch.properties file with properties to customize
-
create a release trigger branch on a Git repository
GIT_REPOSITORY_URL=<URL of the Git repository> bash -c 'source ./maven-auto-release.sh && createReleaseTriggerBranch $GIT_REPOSITORY_URL'- follow the instructions of the README file created on the release trigger branch of the Git repository
The Maven auto releaser tool is licensed under the Apache License, Version 2.0. See LICENSE for the full license text.