Chapter 2. Creating a custom container image

You can create a container image from your Quarkus application using one of the following methods:

  • Creating a container manually
  • Creating a container using the OpenShift Docker build
Important

Compiling a Quarkus application to a native executable consumes a lot of memory during analysis and optimization. You can limit the amount of memory used during native compilation by setting the quarkus.native.native-image-xmx configuration property. Setting low memory limits might increase the build time.

2.1. Creating a container manually

This section shows you how to manually create a container image with your application for Linux X86_64. When you produce a native image using the Quarkus Native container it creates an executable that targets the Linux X86_64 operating system. If your host operating system is different from this, you will not be able to run the binary directly and you will need to create a container manually.

Your Quarkus Getting Started project includes a Dockerfile.native in the src/main/docker directory with the following content: 

FROM registry.access.redhat.com/ubi8/ubi-minimal
WORKDIR /work/
COPY target/*-runner /work/application
RUN chmod 775 /work
EXPOSE 8080
CMD ["./application", "-Dquarkus.http.host=0.0.0.0"]
Universal Base Image (UBI)

The Dockerfiles use UBI as a base image. This base image was designed to work in containers. The Dockerfiles use the minimal version of the base image to reduce the size of the produced image.

Procedure

  1. Build a native Linux executable using one of the following methods:

    1. Build a native executable with Docker: 

      ./mvnw package -Pnative -Dquarkus.native.container-build=true

    2. Build a native executable with Podman: 

      ./mvnw package -Pnative -Dquarkus.native.container-build=true -Dquarkus.native.container-runtime=podman

  2. Build the container image using one of the following methods:

    1. Build the container image with Docker: 

      docker build -f src/main/docker/Dockerfile.native -t quarkus-quickstart/getting-started .

    2. Build the container image with Podman 

      podman build -f src/main/docker/Dockerfile.native -t quarkus-quickstart/getting-started .

  3. Run the container:

    1. Run the container with Docker: 

      docker run -i --rm -p 8080:8080 quarkus-quickstart/getting-started

    2. Run the container with Podman: 

      podman run -i --rm -p 8080:8080 quarkus-quickstart/getting-started

For information about deploying Quarkus Maven applications on Red Hat OpenShift Container Platform, see Deploying your Quarkus applications on Red Hat OpenShift Container Platform.

2.2. Creating a container using the OpenShift Docker build

You can create a container image for your Quarkus application using the OpenShift Docker build strategy. This strategy creates a container using a build configuration in the cluster.

Prerequisites

  • You have access to a Red Hat OpenShift Container Platform cluster and the latest version of the OpenShift CLI (oc) is installed. For information about installing oc, see the "Installing the CLI" section of the Installing and configuring OpenShift Container Platform clusters guide.
  • A URL for the OpenShift API endpoint.

Procedure

  1. Log in to the OpenShift CLI: 

    oc login -u <username_url>

  2. Create a new project in OpenShift: 

    oc new-project <project_name>

  3. Create a build config based on the src/main/docker/Dockerfile.native file: 

    cat src/main/docker/Dockerfile.native | oc new-build --name <build_name> --strategy=docker --dockerfile -

  4. Build the project: 

    oc start-build <build_name> --from-dir .

  5. Deploy the project to OpenShift: 

    oc new-app <build_name>