Re: New SVG-based renderMethod examples in VC Playground

On Mon, Aug 5, 2024 at 3:35 PM Manu Sporny <msporny@digitalbazaar.com>
wrote:

> Did I answer the question you asked?

I think you did.  The bartender asks for age and address, but I only want
to reveal age.  I expect that's already part of the UX, so the rendering
follows my instructions, not the bartender's.  Right?

--------------
Alan Karp


On Mon, Aug 5, 2024 at 3:35 PM Manu Sporny <msporny@digitalbazaar.com>
wrote:

> On Mon, Aug 5, 2024 at 6:03 PM Alan Karp <alanhkarp@gmail.com> wrote:
> > Is there a way to support selective disclosure?
>
> Yes, in fact, we're not that far off in being able to fully demonstrate
> that.
>
> The SVG template uses markup that looks like this for the claims that
> are pulled from the VC data. For example, the SVG markup in the
> Employment Authorization Document does this for the photo:
>
> <image xlink:href="{{credentialSubject.image}}" id="photo"
> width="2048" height="2048" ...
>
> ... and this for the document identifier:
>
> <tspan id="tspan63" x="0"
>
> y="0">{{credentialSubject.employmentAuthorizationDocument.identifier}}</tspan>
>
> Note the Handlebars markup[1], which pulls claims directly from the
> signed VC and injects that data into the SVG template expressed in the
> renderMethod property in the VC.
>
> Some of the issuers in the VC Playground (like the default one) uses
> ECDSA-SD (a selective disclosure cryptography suite) to sign the
> document. A selective disclosure of the renderMethod template and a
> handful of claims would result in a rendering that only contained data
> for the items that were selectively disclosed. All the other templated
> variables in the SVG would evaluate to an empty value. We could make
> this more apparent by rendering black bars for the missing information
> in the visual depiction of the credential.
>
> So, yes, not only is there a way, it's already there in the VC
> Playground today. We don't have a verifier that requests a selectively
> disclosed VC using a render method yet, nor does it render using those
> black bars for the redacted information, but it doesn't feel like a
> lot of work to get there based on where we are today. Just a "simple
> matter of code" that adds the right query to the playground, and
> verifier-based rendering. I'll check with the team to figure out the
> lift for such a thing -- I think it would be useful to demonstrate how
> we can achieve the question you asked, Alan.
>
> Did I answer the question you asked?
>
> -- manu
>
> [1]https://handlebarsjs.com/
>
> --
> Manu Sporny - https://www.linkedin.com/in/manusporny/
> Founder/CEO - Digital Bazaar, Inc.
> https://www.digitalbazaar.com/
>