pkg/operator/status: Block ClusterVersion updates until multi-arch transitions complete

By setting a new 'operator-image' entry in the ClusterOperator
status.versions manifest, so the cluster-version operator will wait
for the in-cluster status to have both [1]:

* The 'operator' value we already declare, so the CVO waits for us to
  hit the target version.
* The 'operator-image' value I'm adding in this commit, to help
  distinguish between single-arch and multi-arch targets which share
  the same version string (but have unique release and MCO pullspecs).

Without this change, the CVO immediately thinks the MCO has completed
its update ("'operator' matches 4.13.0, and that's all I've been asked
to match!") while the MCO is still working to pivot to the new,
multi-arch component.  Folks who try to take advantage of the new
multi-arch functionality at this point might be surprised to have
ClusterVersion claiming the update to multi-arch is complete, even
though the MCO is still only part way through that transition, and has
not yet positioned itself to point at the multi-arch RHCOS image when
new Machines try to come up [2].

[1]: https://github.com/openshift/cluster-version-operator/blob/e546515213c8681ca44c52f178401cd47ad07d11/pkg/cvo/internal/operatorstatus.go#L174-L176
[2]: https://issues.redhat.com/browse/OCPBUGS-10300

Author: wking

cmd/machine-config-operator/main.go

@@ -22,6 +22,7 @@ var (
 func init() {
 	rootCmd.PersistentFlags().AddGoFlagSet(flag.CommandLine)
 	rootCmd.PersistentFlags().StringVar(&version.ReleaseVersion, "payload-version", version.ReleaseVersion, "Version of the openshift release")
+	rootCmd.PersistentFlags().StringVar(&version.OperatorImage, "operator-image", version.OperatorImage, "Image pullspec for the current machine-config operator")
 }
 
 func main() {

install/0000_80_machine-config_04_deployment.yaml

@@ -31,6 +31,7 @@ spec:
         - "start"
         - "--images-json=/etc/mco/images/images.json"
         - "--payload-version=0.0.1-snapshot"
+        - "--operator-image=placeholder.url.oc.will.replace.this.org/placeholdernamespace:machine-config-operator"
         resources:
           requests:
             cpu: 20m

install/0000_80_machine-config_06_clusteroperator.yaml

@@ -11,6 +11,8 @@ status:
   versions:
     - name: operator
       version: "0.0.1-snapshot"
+    - name: operator-image
+      version: placeholder.url.oc.will.replace.this.org/placeholdernamespace:machine-config-operator
   relatedObjects:
     - group: ""
       name: openshift-machine-config-operator

pkg/operator/operator.go

@@ -314,6 +314,7 @@ func New(
 	optr.apiserverListerSynced = apiserverInformer.Informer().HasSynced
 
 	optr.vStore.Set("operator", version.ReleaseVersion)
+	optr.vStore.Set("operator-image", version.OperatorImage)
 
 	return optr
 }

pkg/version/version.go

@@ -14,6 +14,10 @@ var (
 	// This will be injected by the payload build process.
 	ReleaseVersion = "0.0.1-snapshot"
 
+	// OperatorImage is the image pullspec for the current machine-config operator.
+	// This will be injected by the payload build process.
+	OperatorImage = "placeholder.url.oc.will.replace.this.org/placeholdernamespace:was-not-built-properly"
+
 	// Raw is the string representation of the version. This will be replaced
 	// with the calculated version at build time.
 	Raw = "v0.0.0-was-not-built-properly"