Verifiable Credentials Advanced Concepts

[u-veys]

When I tried to do a transfer using a verifiable credential that has an evidence property, I noticed that it didn’t work. After checking VerifiableCredential.java and JsonObjectToVerifiableCredentialTransformer.java, it looks like the EDC only supports the basic concepts of the Data Model. The advanced concepts, like the evidence property, aren’t supported yet. When the transformation happens in JsonObjectToVerifiableCredentialTransformer.java, it fails because of the evidence property, and this leads to an 'Unauthorized' failure.

Connector/extensions/common/iam/identity-trust/identity-trust-transform/src/main/java/org/eclipse/edc/iam/identitytrust/transform/to/JsonObjectToVerifiableCredentialTransformer.java

Lines 82 to 84 in 7a49cf1

	default ->
	context.reportProblem("Unknown property: %s type: %s".formatted(key, jsonValue.getValueType().name()));
	}

My question is: is there a way to use credentials that include advanced concepts like the evidence property?

[paullatzelsperger]

I can think of only one way to do this, and this is trying to exclude the identity-trust-transform module from the build and replacing it with your custom module. You will have to replace all its transformers. I have not tried this, so I don't know if there are any interdependencies between modules or something but you could give it a shot. However, VerifiableCredential would not contain that property, but at least your ingress wouldn't fail anymore.

That said, I wanted to point out that we currently have no plans of adding any of the advanced concepts to our implementation, and we have made a conscientious decision to make our transformers as restrictive as possible, i.e. not allowing unknown properties for various reasons so you wouldn't be able to do anything with that property anyway.