Integration testing has to this point relied on patching serving codecs for built-in APIs. The
test-only patching is removed and replaced by feature gated checks at runtime.
The media type application/cbor describes exactly one encoded item. As a new (to Kubernetes) format
with no existing clients, streaming/watch responses will use the application/cbor-seq media
type. CBOR watch responses conform to the specification of CBOR Sequences and are encoded as the
concatenation of zero or more items with no additional framing.
For alpha, there is one apiserver feature gate and two client-go feature gates controlling
CBOR. They were initially wired to separate test-only feature gate instances in order to prevent
them from being configurable at runtime via command-line flags or environment variables (for
client-go feature gates outside of Kubernetes components). All of the integration tests required by
the KEP as alpha criteria have been implemented. This adds the feature gates to the usual feature
gate instances and removes the temporary code to support separate test-only feature gate instances.
If a client is configured to encode request bodies to CBOR, but the server does not support CBOR,
the server will respond with HTTP 415 (Unsupported Media Type). By feeding this response back to the
RESTClient, subsequent requests can fall back to JSON, which is assumed to be acceptable.
As with the apiserver feature gate for CBOR as a serving and storage encoding, the client feature
gates for CBOR are being initially added through a test-only feature gate instance that is not wired
to environment variables or to command-line flags and is intended only to be enabled
programmatically from integration tests. The test-only instance will be removed as part of alpha
graduation and replaced by conventional client feature gating.
Automatic merge from submit-queue
replace global registry in apimachinery with global registry in k8s.io/kubernetes
We'd like to remove all globals, but our immediate problem is that a shared registry between k8s.io/kubernetes and k8s.io/client-go doesn't work. Since client-go makes a copy, we can actually keep a global registry with other globals in pkg/api for now.
@kubernetes/sig-api-machinery-misc @lavalamp @smarterclayton @sttts
