O3-2753: Add ability to publish frontend configuration to Maven

[ibacher]

Apparently I lied and there was more. This adds a POM and some structure to allow us to publish the spa-assemble-config.json (with version numbers) and the spa-build-config.json files as a Maven artifact.

In CI we will have something like this:

docker create --name=openmrs-frontend-container openmrs/openmrs-reference-application-3-frontend:nightly
docker cp openmrs-frontend-container:/usr/share/nginx/html/spa-assemble-config.json src/main/resources/spa-assemble-config.json
docker rm openmrs-frontend-container

Note that this means that the POM in the frontend directory is intended only as a "publication POM" and not a "actual build".

[rbuisson]

@ibacher , mvn clean package -Pfrontend does not seem to output a file. There is a Zip but it looks like it's empty.

Is that supposed to be?

[ibacher]

@rbuisson That's kind of what I meant that this is a "publication POM" not a "actual build", that is the POM here depends on the Docker build rather than the other way around. The main build for the RefApp is still docker compose build, there's just an additional step that will extract the necessary file from the built container.

[ibacher]

@rbuisson As an update, you can see the published Zip here.

[rbuisson]

Thanks. I understood it the other way around. As in "publication POM" was to only output the file that will be published, and not used anywhere else in the project.

I can see the published artefact 👍🏻 .