Chainguard Container for open-liberty

Open Liberty is a highly composable, fast to start, dynamic application server runtime environment.

Chainguard Containers are regularly-updated, secure-by-default container images.

Download this Container Image

For those with access, this container image is available on cgr.dev:

docker pull cgr.dev/ORGANIZATION/open-liberty:latest

Be sure to replace the ORGANIZATION placeholder with the name used for your organization's private repository within the Chainguard Registry.

Compatibility Notes

The Open Liberty Chainguard image was built to work as a drop-in replacement for the official openliberty/open-liberty image. This image supports the same environment variables as the openliberty/open-liberty image but also has a number of key differences, including the following:

• The GID for the default user is 1001 instead of 0
• Open Liberty is located in /usr/share/java/open-liberty instead of /opt/ol/wlp
• The runtime and buildtime helpers can be found in /usr/share/java/open-liberty/helpers instead of /opt/ol/helpers
• The class cache is located in /output/.classCache instead of /opt/java/.scc
• This image is Wolfi-based, unlike upstream, which leverages Ubuntu and UBI

Getting Started

To get started with Chainguard's Open Liberty image, derive an image containing your application.

Example Dockerfile:

FROM cgr.dev/ORGANIZATION/open-liberty:latest

COPY --chown=1001:1001 server.xml /config/server.xml
COPY --chown=1001:1001 path/to/application.jar /config/dropins/application.jar

RUN features.sh && configure.sh

Copy your application to the /config/dropins folder. Any artifacts placed here will be automatically deployed by Open Liberty. These artifacts can be updated, added, and removed without restarting the server.

The server manifest, server.xml, contains all of the features we may want to enable. Append any additional features your application leverages to the server manifest.

The features.sh script will leverage featureUtility to install any features defined in the server manifest. The configure.sh script will apply the server configuration, any iFixes in /fixes, and regenerate the class cache.

Documentation and Resources

• Official Open Liberty documentation.
• Official Open Liberty guides
• Build an application image with Open Liberty

What are Chainguard Containers?

Chainguard Containers are minimal container images that are secure by default.

In many cases, the Chainguard Containers tagged as :latest contain only an open-source application and its runtime dependencies. These minimal container images typically do not contain a shell or package manager. Chainguard Containers are built with Wolfi, our Linux undistro designed to produce container images that meet the requirements of a more secure software supply chain.

The main features of Chainguard Containers include:

• Minimal design, without unnecessary software bloat
• Daily builds to ensure container images are up-to-date with available security patches
• High quality build-time SBOMs attesting to the provenance of all artifacts within the image
• Verifiable signatures provided by Sigstore
• Reproducible builds with Cosign and apko (read more about reproducibility)

For cases where you need container images with shells and package managers to build or debug, most Chainguard Containers come paired with a -dev variant.

Although the -dev container image variants have similar security features as their more minimal versions, they feature additional software that is typically not necessary in production environments. We recommend using multi-stage builds to leverage the -dev variants, copying application artifacts into a final minimal container that offers a reduced attack surface that won’t allow package installations or logins.

Learn More

To better understand how to work with Chainguard Containers, please visit Chainguard Academy and Chainguard Courses.

In addition to Containers, Chainguard offers VMs and Libraries. Contact Chainguard to access additional products.

Trademarks

This software listing is packaged by Chainguard. The trademarks set forth in this offering are owned by their respective companies, and use of them does not imply any affiliation, sponsorship, or endorsement by such companies.