Canonical UCAN COSE representation

[gordonbrander]

Is there a canonical way to represent UCANs in COSE?

COSE is similar to JOSE, but makes a handful of changes:

• Binary for binary data (ofc)
• Two header sections: protected and unprotected
• Numbers instead of string keys
• ...among other things

I found this previous discussion, but did not see any mention of COSE, specifically.

Background context

I am working on a project where UCANs are likely to be a good fit.

We're currently using CBOR to encode metadata, and it would be convenient to express claims as COSE_Sign1. However, I would like to be compatible with UCAN in future.

The alternative I am considering is to use compact-encoded JWTs as strings in the CBOR, but this seems unfortunate given that CBOR already supports binary, and COSE exists.