🌐 Extend VC context

[amimart]

Purpose

At claims submission, when storing them in the cognitarium we store additional information related to the context in which the claims has been submitted (e.g. the address which signed the transaction: dataverse:credential#submitterAddress).

To extend the perspectives and possibilities when using the protocol we could take benefits from storing a more complete context, for instance having a submission block height would allow the implementation of on-chain rate limit for execution orders.

Proposal

I propose to enhance the claim stored context to store two kind of context data:

• body: related to the original verifiable credential carrying the claims, under the dataverse:credential:body uri;
• header: related to the submission context, under the dataverse:credential:header uri;

Here's an exhaustive context information I've identified so far:

• dataverse:credential:header#height: the block height at which the transaction was executed;
• dataverse:credential:header#timestamp: the block timestamp at which the transaction was executed;
• dataverse:credential:header#tx_index: the block transaction's index containing the original SubmitClaims message, if any;
• dataverse:credential:header#sender: the address who sent the transaction holding the SubmitClaims message;
• dataverse:credential:body#type: the credential type;
• dataverse:credential:body#issuer: the credential issuer;
• dataverse:credential:body#validFrom: the credential validity start date;
• dataverse:credential:body#validUntil: the credential validity end date;
• dataverse:credential:body#subject: the credential subject;
• dataverse:credential:body#claim: the credential claims;