s2i.build.kind should be more fine grained

[jfdenise]

Today the kind field applies to both runtime and builder image. We need to set the kind for runtime and the kind for builder. kind would stay, and be applied to both, but builderKind and runtimeKind would override the kind (raw suggestion).

[jmesnil]

Thanks this sounds doable.

We would add:

build:
  s2i:
    kind: # either ImageStreamTag or DockerImage (existing field that applies to both builder and runtime image
    builderKind: # either ImageStreamTag or DockerImage
    runtimeKind: # either ImageStreamTag or DockerImage

In the templates, we would use build.s2i.builderKind (resp. build.s2i.runtimeKind) to set the builder (resp. runtime) image if it is defined or defaults to build.s2i.kind.

So if you want to use a image stream for the builder image only, your config would look like:

s2i:
  build:
    builderImage: jaxrs-builder-build-artifacts:latest
    builderKind: ImageStreamTag

This configuration would use the default runtime image (coming as a Docker image).