Images are built with dirty tree state

[timebertt]

What would you like to be added:
Currently our Docker images are built with a dirty tree state.
I discovered this while looking into how the pipeline appends the commit hash to the version file (ref).

If the version file is the only thing we touch while building, I would propose to only use the EFFECTIVE_VERSION env var to compute the correct version inside the various build scripts/make targets instead of writing it to the VERSION file.

Why is this needed:
For example:

$ curl -k https://gardener-apiserver:8080/version -H "Authorization: Bearer <redacted>"
{
  "major": "v1",
  "minor": "6",
  "gitVersion": "v1.6.4",
  "gitCommit": "f8a5056de1a3a8fe7cdee939172ba79b2386a395",
  "gitTreeState": "dirty",
  "buildDate": "2020-06-21T19:35:09+00:00",
  "goVersion": "go1.14.3",
  "compiler": "gc",
  "platform": "linux/amd64"
}

/cc @rfranzke

[timebertt]

Ref gardener/gardener#2500

[ccwienk]

@tim-ebert : actually, there is a configuration option inject_effective_version (https://gardener.github.io/cc-utils/traits/version.html), which will by default not alter the source tree. I just checked - this is set to true for gardener/gardener (branch.cfg in refs/meta/ci).
--> so you could simply achieve this by changing this either to false explicitly, or removing the configuration.

[ccwienk]

@tim-ebert , as just discussed:

• worktree / source directory is currently the only way we expose through our pipeline contract to pass parameters to container image builds, so - while it is possible to disable version injection - you will have to keep injecting the effective version as currently configured
• we (cicd team) shall extend the pipeline contract such that arguments can be passed to the container image builds

[timebertt]

Thanks @ccwienk for your help.
I opened gardener/gardener#2608 to ignore the injected VERSION file during build time.
/unassign

Indeed, it would be great to inject the version by setting the EFFECTIVE_VERSION docker build arg in our pipelines.
/assign @ccwienk

[rfranzke]

/touch

[ccwienk]

@timebertt : I would like to add as a smallish update on the matter that since last week, it is possible to pass arguments to docker-build using the build_args attr in the pipeline-definition:

https://gardener.github.io/cc-utils/traits/publish.html#trait-publish

[timebertt]

Can we inject the effective version into docker builds then with this instead of via the version file?