I've been using Garnet with my k8s setup. They don't have native kube api integration and I suggest developing a controller. But right now you can use the CLI to append any commands or scripts in your docker containers to supply them env variables at build or run time.

E.g. in a Dockerfile … RUN garnet run --service-key=$GARNET_SERVICE_KEY -- npm start

If this container is running on k8s, you can supply $GARNET_SERVICE_KEY as a k8s secret mounted on the pod