/docker-maven

Docker image with Maven

Primary LanguageShellApache License 2.0Apache-2.0

docker-maven

Supported tags and respective Dockerfile links

What is Maven?

Apache Maven is a software project management and comprehension tool. Based on the concept of a project object model (POM), Maven can manage a project's build, reporting and documentation from a central piece of information.

How to use this image

Create a Dockerfile in your Maven project

FROM maven:3.3-jdk-7-onbuild
CMD ["do-something-with-built-packages"]

Put this file in the root of your project, next to the pom.xml.

This image includes multiple ONBUILD triggers which should be all you need to bootstrap. The build will COPY . /usr/src/app and RUN mvn install.

You can then build and run the image:

docker build -t my-maven .
docker run -it --name my-maven-script my-maven

Run a single Maven command

For many simple projects, you may find it inconvenient to write a complete Dockerfile. In such cases, you can run a Maven project by using the Maven Docker image directly, passing a Maven command to docker run:

docker run -it --rm --name my-maven-project -v "$(pwd)":/usr/src/mymaven -w /usr/src/mymaven maven:3.3-jdk-7 mvn clean install

Reusing the Maven local repository

The local Maven repository can be reused across containers by creating a volume and mounting it in /root/.m2.

docker volume create --name maven-repo
docker run -it -v maven-repo:/root/.m2 maven mvn archetype:generate # will download artifacts
docker run -it -v maven-repo:/root/.m2 maven mvn archetype:generate # will reuse downloaded artifacts

Packaging a local repository with the image

The $MAVEN_CONFIG dir (default to /root/.m2) is configured as a volume so anything copied there in a Dockerfile at build time is lost. For that the dir /usr/share/maven/ref/ is created, and anything in there will be copied on container startup to $MAVEN_CONFIG.

To create a pre-packaged repository, create a pom.xml with the dependencies you need and use this in your Dockerfile. /usr/share/maven/ref/settings-docker.xml is a settings file that changes the local repository to /usr/share/maven/ref/repository, but you can use your own settings file as long as it uses /usr/share/maven/ref/repository as local repo.

COPY pom.xml /tmp/pom.xml
RUN mvn -B -f /tmp/pom.xml -s /usr/share/maven/ref/settings-docker.xml dependency:resolve

To add your custom settings.xml file to the image use

COPY settings.xml /usr/share/maven/ref/

For an example, check the tests dir

Running as non-root

Maven needs the user home to download artifacts to, and if the user does not exist in the image an extra user.home Java property needs to be set.

For example, to run as user 1000 mounting the host' Maven repo

docker run -v ~/.m2:/var/maven/.m2 -ti --rm -u 1000 -e MAVEN_CONFIG=/var/maven/.m2 maven mvn -Duser.home=/var/maven archetype:generate

Building

Build with the usual

docker build -t maven .

Tests are written using bats under the tests dir. Use the env var TAG to choose what image to run tests against.

TAG=jdk-8 bats tests

or run all the tests with

for tag in jdk-7 jdk-8 jdk-9; do TAG=$tag bats tests; done

Bats can be easily installed with brew install bats on OS X

User Feedback

Issues

If you have any problems with or questions about this image, please contact us through a GitHub issue.

You can also reach many of the official image maintainers via the #docker-library IRC channel on Freenode.

Contributing

You are invited to contribute new features, fixes, or updates, large or small; we are always thrilled to receive pull requests, and do our best to process them as fast as we can.

Before you start to code, we recommend discussing your plans through a GitHub issue, especially for more ambitious contributions. This gives other contributors a chance to point you in the right direction, give you feedback on your design, and help you find out if someone else is working on the same thing.