Automatic merge from submit-queue
make the resource prefix in etcd configurable for cohabitation
This looks big, its not as bad as it seems.
When you have different resources cohabiting, the resource name used for the etcd directory needs to be configurable. HPA in two different groups worked fine before. Now we're looking at something like RC<->RS. They normally store into two different etcd directories. This code allows them to be configured to store into the same location.
To maintain consistency across all resources, I allowed the `StorageFactory` to indicate which `ResourcePrefix` should be used inside `RESTOptions` which already contains storage information.
@lavalamp affects cohabitation.
@smarterclayton @mfojtik prereq for our rc<->rs and d<->dc story.
The codec factory should support two distinct interfaces - negotiating
for a serializer with a client, vs reading or writing data to a storage
form (etcd, disk, etc). Make the EncodeForVersion and DecodeToVersion
methods only take Encoder and Decoder, and slight refactoring elsewhere.
In the storage factory, use a content type to control what serializer to
pick, and use the universal deserializer. This ensures that storage can
read JSON (which might be from older objects) while only writing
protobuf. Add exceptions for those resources that may not be able to
write to protobuf (specifically third party resources, but potentially
others in the future).
Pass down into the server initialization the necessary interface for
handling client/server content type negotiation. Add integration tests
for the negotiation.
A NegotiatedSerializer is passed into the API installer (and
ParameterCodec, which abstracts conversion of query params) that can be
used to negotiate client/server request/response serialization. All
error paths are now negotiation aware, and are at least minimally
version aware.
Watch is specially coded to only allow application/json - a follow up
change will convert it to use negotiation.
Ensure the swagger scheme will include supported serializations - this
now includes application/yaml as a negotiated option.
