Quarkus - Container Images

Quarkus provides extensions for building (and pushing) container images. Currently it supports:

• Jib

• Docker

• S2I

Container Image extensions

Jib

The extension quarkus-container-image-jib is powered by Jib for performing container image builds. The major benefit of using Jib with Quarkus is that all the dependencies (everything found under target/lib) are cached in a different layer than the actual application making rebuilds really fast and small (when it comes to pushing). Another important benefit of using this extension is that it provides the ability to create a container image without having to have any dedicated client side tooling (like Docker) or running daemon processes (like the Docker daemon) when all that is needed is the ability to push to a container image registry.

To use this feature, add the following extension to your project:

./mvnw quarkus:add-extension -Dextensions="container-image-jib"

Including extra files

There are cases when additional files (other than ones produced by the Quarkus build) need to be added to a container image. To support these cases, Quarkus copies any file under src/main/jib into the built container image (which is essentially the same idea that the Jib Maven and Gradle plugins support). For example, the presence of src/main/jib/foo/bar would result in /foo/bar being added into the container filesystem.

Docker

The extension quarkus-container-image-docker is using the Docker binary and the generated Dockerfiles under src/main/docker in order to perform Docker builds.

To use this feature, add the following extension to your project.

./mvnw quarkus:add-extension -Dextensions="container-image-docker"

S2I

The extension quarkus-container-image-s2i is using S2I binary builds in order to perform container builds inside the OpenShift cluster. The idea behind the binary build is that you just upload the artifact and its dependencies to the cluster and during the build they will be merged to a builder image (defaults to fabric8/s2i-java).

The benefit of this approach, is that it can be combined with OpenShift’s DeploymentConfig that makes it easy to roll out changes to the cluster.

To use this feature, add the following extension to your project.

./mvnw quarkus:add-extension -Dextensions="container-image-s2i"

S2I builds require creating a BuildConfig and two ImageStream resources, one for the builder image and one for the output image. The creation of such objects is being taken care of by the Quarkus Kubernetes extension.

Building

To build a container image for your project, quarkus.container-image.build=true needs to be set using any of the ways that Quarkus supports.

./mvnw clean package -Dquarkus.container-image.build=true

Pushing

To push a container image for your project, quarkus.container-image.push=true needs to be set using any of the ways that Quarkus supports.

./mvnw clean package -Dquarkus.container-image.push=true

Selecting among multiple extensions

It does not make sense to use multiple extension as part of the same build. When multiple container image extensions are present, an error will be raised to inform the user. The user can either remove the uneeded extensions or select one using application.properties.

For example, if both container-image-docker and container-image-s2i are present and the user needs to use container-image-docker:

quarkus.container-image.builder=docker

Customizing

The following properties can be used to customize the container image build process.

Container Image Options

Jib Options

In addition to the generic container image options, the container-image-jib also provides the following options:

Docker Options

In addition to the generic container image options, the container-image-docker also provides the following options:

S2I Options

In addition to the generic container image options, the container-image-s2i also provides the following options: