feat: Add support for scratch-based container images

[timflannagan]

Signed-off-by: timflannagan [email protected]

[timflannagan]

Local output because i didn't see any tests:

$ ./target/release/dcp quay.io/tflannag/bundles:resolveset-v0.0.2 -p manifests
PullStatus { status: "Pulling from tflannag/bundles", id: Some("resolveset-v0.0.2"), progress: None, progress_detail: None }
PullStatus { status: "Digest: sha256:145ccb5e7e73d4ae914160c066e49f35bc2be2bb86e4ab0002a802aa436599bf", id: None, progress: None, progress_detail: None }
PullStatus { status: "Status: Image is up to date for quay.io/tflannag/bundles:resolveset-v0.0.2", id: None, progress: None, progress_detail: None }
cmd: [""]
"1fa75f27a1374f5891558e0f76fa2d0e8ccce18c088d86fa040f819d057a7eea"

$ cat manifests/bi.yaml 
---

apiVersion: core.rukpak.io/v1alpha1
kind: BundleInstance
metadata:
  name: olm-v0.20.0-api
spec:
  provisionerClassName: core.rukpak.io/plain
  template:
    spec:
      provisionerClassName: core.rukpak.io/plain
      source:
        type: image
        image:
          ref: quay.io/tflannag/olm-plain-bundle:olm-api-v0.20.0
---

apiVersion: core.rukpak.io/v1alpha1
kind: BundleInstance
metadata:
  name: olm-v0.20.0-crds
spec:
  provisionerClassName: core.rukpak.io/plain
  template:
    spec:
      provisionerClassName: core.rukpak.io/plain
      source:
        type: image
        image:
          ref: quay.io/tflannag/olm-plain-bundle:olm-crds-v0.20.0

And the behavior before these fixes:

$ ./dcp quay.io/tflannag/bundles:resolveset-v0.0.2 -p manifests
PullStatus { status: "Pulling from tflannag/bundles", id: Some("resolveset-v0.0.2"), progress: None, progress_detail: None }
PullStatus { status: "Digest: sha256:145ccb5e7e73d4ae914160c066e49f35bc2be2bb86e4ab0002a802aa436599bf", id: None, progress: None, progress_detail: None }
PullStatus { status: "Status: Image is up to date for quay.io/tflannag/bundles:resolveset-v0.0.2", id: None, progress: None, progress_detail: None }
Error: Error(Fault { code: 400, message: "No command specified" })

[timflannagan]

Alternatively: we allow users to specify a command through a CLI flag but I'm not sure why we'd need to do that.

[exdx]

Alternatively: we allow users to specify a command through a CLI flag but I'm not sure why we'd need to do that.

Yes, I think for the narrow use-case dcp is trying to fulfill, we can always use a dummy command.

[tylerslaton]

This looks good to me but I'm an advocate for adding a test case for this so that we don't regress moving forward.