ci: build inside a builder container

[sverrehu]

Something like this, @erikgb? We will, of course, need to ditch anything maven from the actions if we select to go this way.

[erikgb]

Something like this, @erikgb? We will, of course, need to ditch anything maven from the actions if we select to go this way.

Yes! ❤️

Can you remove the maven build from outside the Docker-build?

[sverrehu]

Can you remove the maven build from outside the Docker-build?

Done. Although I'm still on thin ice when it comes to GitHub actions, so not sure it is correct.

[erikgb]

We should also probably test changing pom.xml. That should invalidate the Docker cache from the copy pom.xml statement. I expect that to be the same as the GH Maven cache. We should not have SNAPSHOT-dependencies. If we did, those would be problematic - since they will not invalidate the cache.

[sverrehu]

We should also probably test changing pom.xml.

I tested locally, first changing the pom and then a source file. The results were as we hope for. But I'm only using docker build, and nothing fancy.

[erikgb]

We should also probably test changing pom.xml.

I tested locally, first changing the pom and then a source file. The results were as we hope for. But I'm only using docker build, and nothing fancy.

The GH Docker cache setup is quite aggressive, but this seems to work as we want.

[sverrehu]

The GH Docker cache setup is quite aggressive, but this seems to work as we want.

There are commits for "change pom" and "change source file" that probably have some action runs.

Looks fine to me.

[erikgb]

LGTM! Let's try this for some time!