Jammy base run image with fonts support

This is DTForce's take on creating a base OCI run image for containerized (cloud) deployments of Java applications with support for Jasper Reports and and some commonly used fonts. This derrives from tha fact, that base OCI images, although beautifuly lean and otherwise fantastic in almost every other aspect, lack some type-related libraries and fonts.

The basic idea comes from this stack overflow question, as Jasper-based reporting in many opensource tools that we are using (including Jmix) are throwing the infamous RuntimeException: Fontconfig head is null, check your fonts or fonts configuration at java.desktop/sun.awt.FontConfiguration.getVersion() exception on some reporting/export functions when run on base OCI images (not the bloated full images).

On top of that, we are adding the MS core TTF fonts as they introduce typefaces commonly used in these reports (like Arial) and add support for accented characters commonly used in many European languages (including the CEE ones).

Based on latest paketobuildpacks/run-jammy-base image with

• libfreetype6
• fontconfig
• ttf-mscorefonts-installer

Legal

Deliberations and conclusions that you should be legally able to distribute (and embed) MS core TTF fonts are here:

• https://law.stackexchange.com/questions/84185/am-i-allowed-to-use-microsofts-truetype-core-fonts-outside-my-computer
• https://learn.microsoft.com/en-us/typography/fonts/font-faq

Basic usage

Just use the dtforce/run-jammy-base-ttfonts:latest as the runImage of your bootBuildImage Gradle task.

Advanced usage

If you want to build your own runimage (feel free to fork) or suggest a useful change to this repo (we weill accept sensible pull requests that contribute to general usability of the image and do not bloat it unnecessarily).

1. Touch the Dockerfile and make your adjustments as required
2. Build the image docker build . -t dtforce/run-jammy-base-ttfonts:0.1.143 -t dtforce/run-jammy-base-ttfonts:latest (or your tag)
3. Push the image docker push dtforce/run-jammy-base-ttfonts:0.1.143 && docker push dtforce/run-jammy-base-ttfonts:latest (or your tag)
4. Use the image as runImage of the bootBuildImage Gradle task in your project (see the Basic usage above)

Closing remarks and troubleshooting

This works in a way that /opt (workspace) where your app would be normally residing is not writable to the app and if you need to have a working/temp dir you need to direct your app to use /home/cnb/

For instance for the popular Jmix framework that we're often using, this would mean setting something like this for production deployment

jmix.core.temp-dir = /home/cnb/.jmix/temp
jmix.core.work-dir = /home/cnb/.jmix/work