I've built a Quarkus 2.7.1 console application using picocli that includes several subcommands. I'd like to be able to run this application within a Kubernetes cluster and decide its arguments at run-time. This is so that I can use the same container image to run the application in different modes within the cluster.
To get things started I added the JIB extension and tried setting the arguments using a configuration value quarkus.jib.jvm-arguments. Unfortunately it seems like this configuration value is locked at build-time so I'm unable to update this at run-time.
Next I tried setting quarkus.args while using default settings for JIB. The configuration value documentation makes it sound general enough for the job but it doesn't seem to have an affect when the application is run in the container. Since most references to this configuration value in documentation are in the context of Dev Mode I'm wondering if this may be disabled outside of that.
How can I get this application running in a container image with its arguments decided at run-time?
You can set quarkus.jib.jvm-entrypoint to any container entrypoint command you want, including scripts. An example in the doc is quarkus.jib.jvm-entrypoint=/deployments/run-java.sh. You could make use of $CLI_ARGUMENTS in such a script. Even something like quarkus.jib.jvm-entrypoint=/bin/sh,-c,'/deployments/run-java.sh $CLI_ARGUMENTS' should work too, as long as you place the script run-java.sh at /deployments in the image. The possibility is limitless.
Also see this SO answer if there's an issue. (The OP in the link put a customer script at src/main/jib/docker/run-java.sh (src/main/jib is Jib's default "extra files directory") so that Jib places the script in the image at /docker/run-java.sh.