[Devfile] OpenShift/K8s tool - reference to content

[skabashnyuk]

Description

At this moment we only one way to reference an external OpenShift/K8s recipe is a file that is located near devfile on GitHub.
And we can use it only with factories.

tools:
  - name: os-recipe
    type: openshift
    local: petclinic.yaml

The idea of this issue is to add the ability to specify a direct link to content.
For example

tools:
  - name: os-recipe
    type: openshift
    url: https://raw.githubusercontent.com/eclipse/che/master/.che-dev.yaml

[skabashnyuk]

@l0rd can you confirm that this is a valid use case? @metlos raised some concerns that after #12713 it might be not necessary.

[l0rd]

@skabashnyuk yes this is what we were talking about at prioritization and makes a lot of sense.

#12713 provide a workaround for clients (i.e. chectl or che dashboard) to inject local yaml definitions in a devfile but it's not suited for users that are manually editing/maintaining a devfile. What I mean is that the solution proposed here is great UX for a user editing a devfile whereas manually editing a yaml inside another yaml is an awful UX.

[metlos]

My concern is about "repeatability" of the workspace. With parts of the devfile externalized out of the surrounding repo, one loses control over how the workspace will actually look like at different points in time. Not sure if that is a concern.

[metlos]

In the light of #12800 and the discussion in #12807, do you think it would be a good idea to actually merge local and url into a single ref or reference? The value would be a generic URI and would be resolved as URI.resolve against the location of the devfile.
localContent would become referenceContent and would behave the same.

[l0rd]

@metlos yes I think it's a good idea to merge local and url. If you want to make it an URI (i.e. local would be file:///<path>) we may call it uri too (but I am ok with reference as well).