Issue a Verifiable Credential

Issue a Verifiable Credential, signed by a did:cheqd Decentralized Identifier (DID), using Veramo.

This tutorial offers step-by-step guidance on how to issue a verifiable credential

⚠️ Before you begin...

Make sure you've correctly configured the cheqd plugin's agent settings for Veramo CLI

Background

The subject (holder) of this credential will be an off-ledger did:key DID. The rationale for using off-ledger DIDs when issuing a credential is because the fact that they aren't persisted on ledger means they cannot be correlated or tracked to specific users/individuals.

This allows a user to have multiple did:key identities, and the identifier/handle they reveal when sharing a Verifiable Credential is context-dependent and better for privacy.

The issuer of the credential, on the other hand, uses an on-ledger did:cheqd DID since this needs to be publicly-accessible and cryptographically verifiable.

Instructions

1. Create an off-ledger did:key subject DID

Normally, the credential holder will provide a did:key DID they have generated themselves (usually done in the background by apps they are using). So, this step typically isn't done by a credential issuer.

For the purpose of this tutorial though, we recommend you create a did:key subject DID for the later steps.

2. Begin credential creation

Start credential generation using:

veramo credential create --json

3. Select a credential proof format

You'll be presented with an multiple options select:

• jwt for JSON credential, encoded as a JSON Web Token (JWT), a W3C compliant proof format.
• lds for JSON-LD credential, encoded as a Data Integrity Proofs, a W3C compliant proof format.

📚 Learn about different types of Verifiable Credentials

If you want to learn more about different types of verifiable credentials please go over to our learning site here.

4. Specify the Issuer DID for the credential

Select which Issuer DID stored in your local storage you'd like to issue the credential from, e.g., did:cheqd:mainnet:zAXwwqZzhCZA1L77ZBa8fhVNjL9MQCHX

The assumption here is that you've either created the issuer DID or stored the DIDDoc by querying it.

5. Specify the subject DID (credential holder's DID)

Select which subject DID from your local agent storage the credential should be issued to, e.g., did:key:z6Mkktr27VZ7TTFoTsD9p79JwtGnQDgJWKGrxJ79quE7M5Yx.

This could the subject DID created in Step 1.

6. Set the Verifiable Credential type

This is currently free-text. However, you can hit Enter to use VerifiableCredential as the default credential context.

7. Specify claim type, i.e., a "field" in the credential

The claim type can be thought of as the label in a form field. It can denote the purpose/attribute being stored in the credential.

For example, the claim type name could refer to the name of an individual.

8. Enter value for claim type

Enter the value of the claim type. For example, you specified name as the claim type, the value could be Alice.

In this tutorial, we will create a credential with only a single name-value pair.

9. Verifiable Credential is generated

At this last step, Veramo CLI generates the credential based on the inputs above.

Note: The human-readable JSON body below is purely for easier parsing by developers/applications. The proof is encoded as JWT or JWS at the bottom of the credential, which can be decoded to reconstruct the entire credential.

Example JSON Verifiable Credential

{
  "@context": [
    "https://www.w3.org/2018/credentials/v1",
    "https://veramo.io/contexts/profile/v1"
  ],
  "type": ["VerifiableCredential", "Profile"],
  "issuer": {
    "id": "did:cheqd:mainnet:zAXwwqZzhCZA1L77ZBa8fhVNjL9MQCHX"
  },
  "issuanceDate": "2022-07-28T15:25:10.000Z",
  "credentialSubject": {
    "name": "Alice",
    "id": "did:key:z6Mkktr27VZ7TTFoTsD9p79JwtGnQDgJWKGrxJ79quE7M5Yx"
  }, 
  "proof": {
    "type": "JwtProof2020",
    "jwt": "eyJhbGciOiJFZERTQSIsInR5cCI6IkpXVCJ9.eyJ2YyI6eyJAY29udGV4dCI6WyJodHRwczovL3d3dy53My5vcmcvMjAxOC9jcmVkZW50aWFscy92MSIsImh0dHBzOi8vdmVyYW1vLmlvL2NvbnRleHRzL3Byb2ZpbGUvdjByb2ZpbGUvdjEiXSwidHlwZSI6WyJWZXJpZmlhYmxlQ3JlZGVudGlhbCIsIlByb2ZpbGUiXSwiY3JlZGVudGlhbFN1YmplY3QiOnsibmFtZSI6IkFsaWNlIn19LCJzdWIiOiJkaWQ6a2V5Ono2TWtrdHIyN1ZaN1RURm9Uc25RRGdKV0tHc0Q5cDc5Snd0R25RRGdKV0tHcnhKNzlxdUU3TTVZeCIsIm5iZiI6MTY1OTAyMTkxMCwiaXNzIjoiZGlkOmNoZXFkOm1haW5uZXQ6ekFYd3dxWnpoQ1pBMUw3N1pCYThmaFZOakw5TVFDSFgifQ.MRqlKuFQzpjLvsW3C2ZSBEf5jfvJCPQBwl-gP1P8bRfNSvjxj9H3eDgDmEf5jfvJCPQBwUDltBr-ZQ3Q7SKVSvCaJHV8TnUzBA"
  }
}

Example JSON-LD Verifiable Credential

{
  "@context": [
    "https://www.w3.org/2018/credentials/v1",
    "https://veramo.io/contexts/profile/v1"
  ],
  "type": [
    "VerifiableCredential",
    "Profile"
  ],
  "issuer": {
    "id": "did:cheqd:testnet:d3e515cf-81af-40cb-9ac1-154827986d29"
  },
  "issuanceDate": "2023-02-07T06:28:33.760Z",
  "credentialSubject": {
    "id": "did:key:z6MkfFb5bMTvm3kXMB5zZSrLGLdtW13wU9w6ByJ76LV7U75a",
    "name": "Alice"
  },
  "proof": {
    "type": "Ed25519Signature2018",
    "created": "2023-02-07T06:28:34Z",
    "verificationMethod": "did:cheqd:testnet:d3e515cf-81af-40cb-9ac1-154827986d29#key-1",
    "proofPurpose": "assertionMethod",
    "jws": "eyJhbGciOiJFZERTQSIsImI2NCI6ZmFsc2UsImNyaXQiOlsiYjY0Il19..LkXa1AxEtoY78-6NwAiIe0viO271RzCMbfJsFgm7muBCHGKGMgTRO0QnGDvA0fygKAVCjvR1xZpgJQEuxlbNAg"
  }
}

Note that the JSON is unordered so the output of the fields could be in a different order

Next steps

You can save the generated Verifiable Credential, as you can later use it to verify the credential cryptographically or generate presentations to show the credential to others.