CustomResourceDefinition parsing and retrieval is not available via
client-go's `kubernetes.Interface`, but rather via a separate
`k8s.io/apiextensions-apiserver` package.
Introduce support for CustomResourceDefintion object parsing and
retrieval. This change facilitates retrieval of CRDs from the k8s API
server, and also provides CRD resources as mock objects.
Also introduce a `NewFakeAPI` constructor, deprecating
`NewFakeClientSets`. Callers need no longer be concerned with discreet
clientsets (for k8s resources vs. CRDs vs. (eventually)
ServiceProfiles), and can instead use the unified `KubernetesAPI`.
Part of #2337, in service to multi-stage check.
Signed-off-by: Andrew Seigner <siggy@buoyant.io>
The `linkerd upgrade` command read the control-plane's config from
Kubernetes, which required the environment to be configured to connect
to the appropriate k8s cluster.
Intrdouce a `linkerd upgrade --from-manifests` flag, allowing the user
to feed the output of `linkerd install` into the upgrade command.
Fixes#2629
Signed-off-by: Andrew Seigner <siggy@buoyant.io>