Resolve DID Document at specific time

[bdesiderio]

Hi! We are working with a scenario where we need to validate a VC signed by a Verification Method that then was removed from the DID Document.

We need to resolve the DID Document at time the VC was signed because we consider valid this VC. If we resolve latest DID Document version we can't validate the VC because the Verification Method was been removed.

Eg:
A valid delegate of a company that then changed because he retired. The signatures he has made would be valid until the moment he retired.

Can we solve this problem with ION?

[csuwildcat]

The data is certainly there, there's just no API for outputting each past revision. It certainly could be added. We think most use cases like this can be more efficiently accomplished by sign old key representations with current keys and expose them through a standard personal datastore you can query from the attached Service Endpoints. This way you have granular ability to represent much more detailed information about the reason for rolling or what UTC date/time range they should be deemed valid from.

[bdesiderio]

It's very nice! We already raised the possibility of adding this feature to the API

Thanks for the reply!

[peacekeeper]

@bdesiderio do you have an example DID where this would be useful?

[bdesiderio]

@bdesiderio do you have an example DID where this would be useful?

We mainly have the use case I discussed above, but another use case we have in mind would be a public key rotation for a verification method. Behind the verification method is the same person but he rotated the public key with which he signs.

But our main use case is this

A valid delegate of a company that then changed because he retired. The signatures he has made would be valid until the moment he retired.

[vriera]

@peacekeeper
Another example would be: The dean of an University is the one in charge of singing the VC, in this case an univesity title. Eventually the dean will retire and it the Verification Method will be removed, but the titles he had signed before must stay valid.

[peacekeeper]

@bdesiderio @vriera thanks, but what I meant was not a use case, but an actual example DID that you would like to resolve at a specific time.

I.e. did:ion:xxxxxx ?

[vriera]

We don't have an actual example DID at ion but this or similiar scenarios have been proposed a few times and we are trying to find a solution.