Verifiable Credentials Step By Step

How to generate Verifiable Credentials

Firstly generate a ed25519 key-pair which can be found at Transmute DID Key:

import * as ed25519 from '@transmute/did-key-ed25519';
import crypto from 'crypto';

const seed = crypto.randomBytes(32).toString('hex');
let key = await Ed25519KeyPair.generate({
  secureRandom: () => {
    return Buffer.from(seed, 'hex');
  },
});

Then you generate a DID document using the key-pair generated above. In order to generate the document, you first have to install npm i @transmute/did-key-common@latest --save and then pass the key generated above to the keyToDidDoc function.

import crypto from 'crypto';
import * as ed25519 from '@transmute/did-key-ed25519';
import { keyToDidDoc } from '@transmute/did-key-common';

const seed = crypto.randomBytes(32).toString('hex');
let ed25519Key = await Ed25519KeyPair.generate({
  secureRandom: () => {
    return Buffer.from(seed, 'hex');
  },
});
const diddoc = await keyToDidDoc(ed25519Key);

If you consoled the diddoc object, you will see something similar to the following:

{                                                                                                                                                                                             
  '@context': [                                                                                                                                                                               
    'https://www.w3.org/ns/did/v1',
    {
      '@base': 'did:key:z6MkqMqrHZnfctNuXJ39fX8vDnUxVrPYL8LiqypWyb2a8S5y'
    }
  ],
  id: 'did:key:z6MkqMqrHZnfctNuXJ39fX8vDnUxVrPYL8LiqypWyb2a8S5y',
  verificationMethod: [
    {
      id: '#z6MkqMqrHZnfctNuXJ39fX8vDnUxVrPYL8LiqypWyb2a8S5y',
      type: 'Ed25519VerificationKey2018',
      controller: 'did:key:z6MkqMqrHZnfctNuXJ39fX8vDnUxVrPYL8LiqypWyb2a8S5y',
      publicKeyBase58: 'BuaohKYEHLtSQoCSyxB5NgvxgH7gvF6N9xub9K4ZDDJb'
    },
    {
      id: '#z6LSku5fknwx7iJCvPG4n5KgCv9Gu5xVLP84AEM49nMX2pJy',
      type: 'X25519KeyAgreementKey2019',
      controller: 'did:key:z6MkqMqrHZnfctNuXJ39fX8vDnUxVrPYL8LiqypWyb2a8S5y',
      publicKeyBase58: 'ADuWEV962FaTpztJFRoitKvo3wRNdmwuHFdNfKhzKSYD'
    }
  ],
  authentication: [ '#z6MkqMqrHZnfctNuXJ39fX8vDnUxVrPYL8LiqypWyb2a8S5y' ],
  assertionMethod: [ '#z6MkqMqrHZnfctNuXJ39fX8vDnUxVrPYL8LiqypWyb2a8S5y' ],
  capabilityInvocation: [ '#z6MkqMqrHZnfctNuXJ39fX8vDnUxVrPYL8LiqypWyb2a8S5y' ],
  capabilityDelegation: [ '#z6MkqMqrHZnfctNuXJ39fX8vDnUxVrPYL8LiqypWyb2a8S5y' ],
  keyAgreement: [ '#z6LSku5fknwx7iJCvPG4n5KgCv9Gu5xVLP84AEM49nMX2pJy' ]
}