Example of Use of renderMethod

[anthonycamilleri]

The renderMethod property is currently at risk. In the European Digital Credentials for Learning implementation, renderMethods are a critical part of the European Learning Model standard, which extends the VC spec.

The use case is that many countries in Europe will prescribe a specific visual look and feel for a credential by law, with the credential therefore needing to explicitly define the renderMethod and ensure that this is locked via the proof. Since no renderMethod currently exists, ELM has extended the data model with a class called elm:DisplayParameter which is described here: SHACL constraints for European Digital Credentials application profile (europa.eu).

The approach currently taken by ELM is to embed an image file directly in the credential, although using integrity protection would be another good way to go about it.

Should renderMethod be included in the standard, it would allow the next version of ELM to deprecate DisplayParameter, and go towards a standards compliant approach.

[msporny]

That's great news @anthonycamilleri (that there is interest through the ELM standard for render methods). We (the Working Group) have been so focused on finalizing the v2.0 core data model and data integrity that it's been difficult to find time to move renderMethod forward, even though we know that many ecosystems are now requiring it.

There is work being incubated in the W3C Credentials Community Group that might also be of interest to ELM:

https://w3c-ccg.github.io/vc-render-method/#the-rendermethod-property

Specifically, we'd love your input on this issue:

w3c-ccg/vc-render-method#9

If we can get agreement that renderMethod would be a useful property for v2.0, we could reserve it and ELM could continue to utilize their DisplayDetail object inside a renderMethod property on the VC.

Your general thoughts on all of these topics would be most welcome.

[PatStLouis]

@anthonycamilleri I'm currently working to bring an OCABundle render method to the vc-render-method spec.

You can look at the Overlays section of the spec to learn more about the capabilities OCA can bring to implementations. The core idea would consist in an OCABundle being published under some governance framework to provide a selection of overlays for software to render the credential depending on their needs.

We are currently doing this work in the scope of the UNTP specification but intend for this to be of general use case.