Support for Verifiable Presentation in form of JSON-LD

[hemantxpatel]

Problem Statement

• During a query catalog request, EDC requests a Verifiable Presentation (a.k.a VP) to Credential Service via /presentations/query endpoint.
• Currently, EDC accepts VP as JWT as well as JSON-LD. EDC is able to parse both JWT and JSON-LD format.
• Same VP (as it is, either in JWT or JSON-LD) is forwarded to BDRS as bearer token in Authorization header.
• BDRS only expects VP in JWT format and fails in case of JSON-LD format. Also the Verifiable Credential (a.k.a VC) inside VP should also be in JWT format.

Proposed Solution

• BDRS should accept VP in JSON-LD format. Only caveat is passing VP as json in header may cause http header size limit. Also doesn't look like a viable solution to pass json data into header.
• In case, EDC accepts a JSON-LD VP, it should encode it into JWT before sending it to BDRS. VC inside VP should also be encoded, as VP may be in JWT format but VC may be in JSON-LD format.

[hemantxpatel]

As discussed in EDC Weekly, tractusx will not support JSON-LD format for VC and VP.