Our registry client is not currently in a good place to be used as the
reference OCI Distribution client implementation. But the registry proxy
currently depends on it. Make the registry client internal to the
distribution application to remove it from the API surface area (and any
implied compatibility promises) of distribution/v3@v3.0.0 without
breaking the proxy.
Signed-off-by: Cory Snider <csnider@mirantis.com>
Replace ping logic with individual functions to extract API version and authorization challenges. The response from a ping operation can be passed into these function. If an error occurs in parsing, the version or challenge will not be used. Sending the ping request is the responsibility of the caller.
APIVersion has been converted from a string to a structure type. A parse function was added to convert from string to the structure type.
Signed-off-by: Derek McGowan <derek@mcgstyle.net> (github: dmcgowan)
