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

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:

CLI
quarkus extension add 'container-image-jib'
Maven
./mvnw quarkus:add-extension -Dextensions="container-image-jib"
Gradle
./gradlew addExtension --extensions="container-image-jib"
In situations where all that is needed to build a container image and no push to a registry is necessary (essentially by having set quarkus.container-image.build=true and left quarkus.container-image.push unset - it defaults to false), then this extension creates a container image and registers it with the Docker daemon. This means that although Docker isn’t used to build the image, it is nevertheless necessary. Also note that using this mode, the built container image will show up when executing docker images.

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.

JVM Debugging

There are cases where the built container image may need to have Java debugging conditionally enabled at runtime.

When the base image has not been changed (and therefore ubi8/openjdk-11-runtime or ubi8/openjdk-17-runtime is used), then the quarkus.jib.jvm-additional-arguments configuration property can be used in order to make the JVM listen on the debug port at startup.

The exact configuration is:

quarkus.jib.jvm-additional-arguments=-agentlib:jdwp=transport=dt_socket\\,server=y\\,suspend=n\\,address=*:5005

Other base images might provide launch scripts that enable debugging when an environment variable is set, in which case you would set than environment variable when launching the container.

Finally, the quarkus.jib.jvm-entrypoint configuration property can be used to completely override the container entry point and can thus be used to either hard code the JVM debug configuration or point to a script that handles the details.

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.

CLI
quarkus extension add 'container-image-docker'
Maven
./mvnw quarkus:add-extension -Dextensions="container-image-docker"
Gradle
./gradlew addExtension --extensions="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.

CLI
quarkus extension add 'container-image-s2i'
Maven
./mvnw quarkus:add-extension -Dextensions="container-image-s2i"
Gradle
./gradlew addExtension --extensions="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.

Buildpack

The extension quarkus-container-image-buildpack is using buildpacks in order to perform container image builds. Under the hood buildpacks will use a Docker daemon for the actual build. While buildpacks support alternatives to Docker, this extension will only work with Docker.

Additionally, the user will have to configure which build image to use (no default image is provided). For example:

quarkus.buildpack.jvm-builder-image=<jvm builder image>

or for native:

quarkus.buildpack.native-builder-image=<native builder image>

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

CLI
quarkus extension add 'container-image-buildpack'
Maven
./mvnw quarkus:add-extension -Dextensions="container-image-buildpack"
Gradle
./gradlew addExtension --extensions="container-image-buildpack"
When using the buildpack container image extension it is strongly advised to avoid adding quarkus.container-image.build=true in your properties configuration as it might trigger nesting builds within builds. It’s preferable to pass it as an option to the build command instead.

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.

CLI
quarkus build -Dquarkus.container-image.build=true
Maven
./mvnw clean package -Dquarkus.container-image.build=true
Gradle
./gradlew build -Dquarkus.container-image.build=true
If you ever want to build a native container image and already have an existing native image you can set -Dquarkus.native.reuse-existing=true and the native image build will not be re-run.

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.

CLI
quarkus build -Dquarkus.container-image.push=true
Maven
./mvnw clean package -Dquarkus.container-image.push=true
Gradle
./gradlew build -Dquarkus.container-image.push=true
If no registry is set (using quarkus.container-image.registry) then docker.io will be used as the default.

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 unneeded 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

Using CI Environments

Various CI environments provide a ready to use container-image registry which can be combined with the container-image Quarkus extensions in order to effortlessly create and push a Quarkus application to said registry.

For example, GitLab provides such a registry and in the provided CI environment, makes available the CI_REGISTRY_IMAGE environment variable (see GitLab’s documentation) for more information), which can be used in Quarkus like so:

quarkus.container-image.image=${CI_REGISTRY_IMAGE}
See this for more information on how to combine properties with environment variables.

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: