spruceid / cacao-zcap Goto Github PK

As noticed by @cobward,

The first value of the CACAO payload resources array is used as the invocation target URI, that is the value of the zcap delegation's invocationTarget property. The invocation target URI is encoded into a root zcap URN to become the root capability id.

In a delegation where the invocation target is attenuated by path or query, the invocationTarget value will be different (attenuated) from that of the parent delegation, but the root zcap id (first value of the capabilityChain array proof.capabilityChain[0]) must still be the same. Therefore, the first value of the CACAO payload resources array (p.resources[0]) cannot be used directly in a secondary delegation for both the invocationTarget value and the root zcap id (proof.capabilityChain[0]). To handle this, the first resource (p.resources[0]) could be split into two (p.resources[0] and p.resources[1]) - one for the invocationTarget and the other for the root zcap id (or, equivalently for the root zcap's invocationTarget).

Currently these terms are defined:

• https://demo.didkit.dev/2022/cacao-zcap/#CacaoZcap2022
• https://demo.didkit.dev/2022/cacao-zcap/#CacaoZcapProof2022
• https://demo.didkit.dev/2022/cacao-zcap/#cacaoPayloadType
• https://demo.didkit.dev/2022/cacao-zcap/#cacaoSignatureType
• https://demo.didkit.dev/2022/cacao-zcap/#cacaoZcapSubstatement

This context file URL is defined:

• https://demo.didkit.dev/2022/cacao-zcap/contexts/v1.json

A better way may be to use w3id.org (https://github.com/perma-id/w3id.org/). e.g. requesting a /cacao/ directory.