Subject may be redundant

[sudo-bmitch]

The subject field seems to be redundant unless we have plans to have other notary fields in the future. This condenses that into a single top level notary field with the payload to be signed.

Signed-off-by: Brandon Mitchell git@bmitch.net

[gokarnm]

The notary field is the top level claim which contains a subject field of type descriptor. This allows us to add additional fields under notary field in future without requiring them to be under the descriptor (which only supports adding them as annotations, and restricts them to key value pairs). Though it seems bit redundant, it allows us to add fields under notary while we discover all of the metadata we want to capture in the payload. I don't see a downside from end customer experience. We can could remove the nesting at RC phase if we end up only requiring the descriptor, and possibly renaming notary to something more descriptive that conveys the claim is about the subject manifest.

[sudo-bmitch]

The extensibility requirement in OCI is for implementations to ignore unknown fields. Which means if there's a need to have more than a key/value pair in an annotation, you could add additional fields to your implementation without breaking other users of the descriptor.

[gokarnm]

No concerns given that we can extend the descriptor with other sub key for complex shapes that cannot fit into annotations. Suggestion, should we rename the top level notary to subjectDescriptor, a more descriptive name.

cc: @priteshbandi @shizhMSFT @SteveLasker

[sudo-bmitch]

Once we have consensus on the name, let me know and I'll rebase it.

[shizhMSFT]

No concerns given that we can extend the descriptor with other sub key for complex shapes that cannot fit into annotations. Suggestion, should we rename the top level notary to subjectDescriptor, a more descriptive name.

notary is good enough to me as long as we have documented it.

[sajayantony]

This sounds more like a subject rather than the notary

[priteshbandi]

+1, the data stored is subjectDescriptor.

[sudo-bmitch]

I've adjusted to use "subject" instead of "notary" based on our discussion today.

[SteveLasker]

LGTM

[priteshbandi]

LGTM

[gokarnm]

LGTM