We first looked at how to issue and verify credentials for a holder to keep. The last step is for a holder to present the VC to a verifier.
To issue/prove a Presentation, we'll use the POST /presentations/prove api.
Our presentation looks like this:
{
"@context": ["https://www.w3.org/2018/credentials/v1"],
"id": "prezid:123",
"type": ["VerifiablePresentation"],
"holder": "holderid:1243",
"verifiableCredential": [
{
"@context": [
"https://www.w3.org/2018/credentials/v1",
{
"DemoPass": {
"@context": {
"@protected": true,
"@version": 1.1,
"email": "schema:email",
"entityId": "schema:identifier",
"firstName": "schema:firstName",
"id": "@id",
"lastName": "schema:lastName",
"parentId": "schema:identifier",
"phone": "schema:telephone",
"schema": "https://schema.org/",
"type": "@type",
"userId": "schema:identifier"
},
"@id": "urn:demopass"
}
}
],
"id": "did:key:zQ3sharUr4F1zxVK8YJKbzx4qi9X6vsmjkphwj7NAwHLz3p2T",
"type": ["VerifiableCredential", "DemoPass"],
"issuer": "did:hedera:testnet:zDGAu46WcY3W3g3WpivM1SHniCUWSfT16F48v6bk9rGuR_0.0.5758795",
"issuanceDate": "2010-01-01T19:23:24Z",
"credentialSubject": {
"email": "[email protected]",
"entityId": 984,
"firstName": "John",
"id": "did:key:zQ3sharUr4F1zxVK8YJKbzx4qi9X6vsmjkphwj7NAwHLz3p2T",
"lastName": "Doe",
"parentId": 120,
"type": "DemoPass",
"userId": 12
},
"proof": {
"type": "Ed25519Signature2018",
"created": "2023-10-27T09:49:23Z",
"verificationMethod": "did:hedera:testnet:zDGAu46WcY3W3g3WpivM1SHniCUWSfT16F48v6bk9rGuR_0.0.5758795",
"proofPurpose": "assertionMethod",
"jws": "eyJhbGciOiJFZERTQSIsImI2NCI6ZmFsc2UsImNyaXQiOlsiYjY0Il19..7AsGXVAmg_LK3ZzuES-ZMGRXeYoeICSvF7qbjxXVy8OTOH7IcTv6VlE7VZO9WVLdOaApnQMvQDaCH32E1amnCg"
}
}
]
}We can identify the presentation's id prezid:123, as well as the holder's identifier holderid:1243.
The holder will wrap a number of Verifiable Credentials in a verifiableCredential array (they've already been issued and have a proof section) in the Presentation and sign it. The complete payload is wrapped in an object with a presentation property and a challenge in an options property.
curl -X 'POST' \
'http://localhost:3004/presentations/prove' \
-H 'accept: application/json' \
-H 'x-api-key: testKey' \
-H 'Content-Type: application/json' \
-d '{
"presentation": {
"@context": [
"https://www.w3.org/2018/credentials/v1"
],
"id": "prezid:123",
"type": [
"VerifiablePresentation"
],
"holder": "holderid:1243",
"verifiableCredential": [
{
"@context": [
"https://www.w3.org/2018/credentials/v1",
{
"DemoPass": {
"@context": {
"@protected": true,
"@version": 1.1,
"email": "schema:email",
"entityId": "schema:identifier",
"firstName": "schema:firstName",
"id": "@id",
"lastName": "schema:lastName",
"parentId": "schema:identifier",
"phone": "schema:telephone",
"schema": "https://schema.org/",
"type": "@type",
"userId": "schema:identifier"
},
"@id": "urn:demopass"
}
}
],
"id": "did:key:zQ3sharUr4F1zxVK8YJKbzx4qi9X6vsmjkphwj7NAwHLz3p2T",
"type": [
"VerifiableCredential",
"DemoPass"
],
"issuer": "did:hedera:testnet:zDGAu46WcY3W3g3WpivM1SHniCUWSfT16F48v6bk9rGuR_0.0.5758795",
"issuanceDate": "2010-01-01T19:23:24Z",
"credentialSubject": {
"email": "[email protected]",
"entityId": 984,
"firstName": "John",
"id": "did:key:zQ3sharUr4F1zxVK8YJKbzx4qi9X6vsmjkphwj7NAwHLz3p2T",
"lastName": "Doe",
"parentId": 120,
"type": "DemoPass",
"userId": 12
},
"proof": {
"type": "Ed25519Signature2018",
"created": "2023-10-27T09:49:23Z",
"verificationMethod": "did:hedera:testnet:zDGAu46WcY3W3g3WpivM1SHniCUWSfT16F48v6bk9rGuR_0.0.5758795",
"proofPurpose": "assertionMethod",
"jws": "eyJhbGciOiJFZERTQSIsImI2NCI6ZmFsc2UsImNyaXQiOlsiYjY0Il19..7AsGXVAmg_LK3ZzuES-ZMGRXeYoeICSvF7qbjxXVy8OTOH7IcTv6VlE7VZO9WVLdOaApnQMvQDaCH32E1amnCg"
}
}
]
},
"options": {
"challenge": "challenge-123"
}
}'Notice the challenge option which could be any string passed by the verifier to verify that the presentation was issued for them specifically and not reused.
This should return a 201 with a signed VP:
{
"@context": ["https://www.w3.org/2018/credentials/v1"],
"type": ["VerifiablePresentation"],
"verifiableCredential": [
{
"@context": [
"https://www.w3.org/2018/credentials/v1",
{
"DemoPass": {
"@context": {
"@protected": true,
"@version": 1.1,
"email": "schema:email",
"entityId": "schema:identifier",
"firstName": "schema:firstName",
"id": "@id",
"lastName": "schema:lastName",
"parentId": "schema:identifier",
"phone": "schema:telephone",
"schema": "https://schema.org/",
"type": "@type",
"userId": "schema:identifier"
},
"@id": "urn:demopass"
}
}
],
"id": "did:key:zQ3sharUr4F1zxVK8YJKbzx4qi9X6vsmjkphwj7NAwHLz3p2T",
"type": ["VerifiableCredential", "DemoPass"],
"issuer": "did:hedera:testnet:zDGAu46WcY3W3g3WpivM1SHniCUWSfT16F48v6bk9rGuR_0.0.5758795",
"issuanceDate": "2010-01-01T19:23:24Z",
"credentialSubject": {
"email": "[email protected]",
"entityId": 984,
"firstName": "John",
"id": "did:key:zQ3sharUr4F1zxVK8YJKbzx4qi9X6vsmjkphwj7NAwHLz3p2T",
"lastName": "Doe",
"parentId": 120,
"type": "DemoPass",
"userId": 12
},
"proof": {
"type": "Ed25519Signature2018",
"created": "2023-10-27T09:49:23Z",
"verificationMethod": "did:hedera:testnet:zDGAu46WcY3W3g3WpivM1SHniCUWSfT16F48v6bk9rGuR_0.0.5758795",
"proofPurpose": "assertionMethod",
"jws": "eyJhbGciOiJFZERTQSIsImI2NCI6ZmFsc2UsImNyaXQiOlsiYjY0Il19..7AsGXVAmg_LK3ZzuES-ZMGRXeYoeICSvF7qbjxXVy8OTOH7IcTv6VlE7VZO9WVLdOaApnQMvQDaCH32E1amnCg"
}
}
],
"id": "prezid:123",
"holder": "holderid:1243",
"proof": {
"type": "Ed25519Signature2018",
"created": "2023-12-18T07:58:11Z",
"verificationMethod": "did:hedera:testnet:zBGujTvDepajDJfndETnYKRNn5xDx4py6t3xNbdbLpKDd_0.0.5787376",
"proofPurpose": "authentication",
"challenge": "challenge-123",
"jws": "eyJhbGciOiJFZERTQSIsImI2NCI6ZmFsc2UsImNyaXQiOlsiYjY0Il19..iy7fpp3Rqh1aVdslsafvqIFgh3wcPAw7e32_RirFlU8TuzA4AcwUUDe3SQYaP1awBh5kEtRd0ETMzp1Gpzj_CQ"
}
}And we'll verify it now:
curl -X 'POST' \
'http://localhost:3004/presentations/verify' \
-H 'accept: application/json' \
-H 'x-api-key: testKey' \
-H 'Content-Type: application/json' \
-d '{
"verifiablePresentation": {
"@context": [
"https://www.w3.org/2018/credentials/v1"
],
"type": [
"VerifiablePresentation"
],
"verifiableCredential": [
{
"@context": [
"https://www.w3.org/2018/credentials/v1",
{
"DemoPass": {
"@context": {
"@protected": true,
"@version": 1.1,
"email": "schema:email",
"entityId": "schema:identifier",
"firstName": "schema:firstName",
"id": "@id",
"lastName": "schema:lastName",
"parentId": "schema:identifier",
"phone": "schema:telephone",
"schema": "https://schema.org/",
"type": "@type",
"userId": "schema:identifier"
},
"@id": "urn:demopass"
}
}
],
"id": "did:key:zQ3sharUr4F1zxVK8YJKbzx4qi9X6vsmjkphwj7NAwHLz3p2T",
"type": [
"VerifiableCredential",
"DemoPass"
],
"issuer": "did:hedera:testnet:zDGAu46WcY3W3g3WpivM1SHniCUWSfT16F48v6bk9rGuR_0.0.5758795",
"issuanceDate": "2010-01-01T19:23:24Z",
"credentialSubject": {
"email": "[email protected]",
"entityId": 984,
"firstName": "John",
"id": "did:key:zQ3sharUr4F1zxVK8YJKbzx4qi9X6vsmjkphwj7NAwHLz3p2T",
"lastName": "Doe",
"parentId": 120,
"type": "DemoPass",
"userId": 12
},
"proof": {
"type": "Ed25519Signature2018",
"created": "2023-10-27T09:49:23Z",
"verificationMethod": "did:hedera:testnet:zDGAu46WcY3W3g3WpivM1SHniCUWSfT16F48v6bk9rGuR_0.0.5758795",
"proofPurpose": "assertionMethod",
"jws": "eyJhbGciOiJFZERTQSIsImI2NCI6ZmFsc2UsImNyaXQiOlsiYjY0Il19..7AsGXVAmg_LK3ZzuES-ZMGRXeYoeICSvF7qbjxXVy8OTOH7IcTv6VlE7VZO9WVLdOaApnQMvQDaCH32E1amnCg"
}
}
],
"id": "prezid:123",
"holder": "holderid:1243",
"proof": {
"type": "Ed25519Signature2018",
"created": "2023-12-18T07:58:11Z",
"verificationMethod": "did:hedera:testnet:zBGujTvDepajDJfndETnYKRNn5xDx4py6t3xNbdbLpKDd_0.0.5787376",
"proofPurpose": "authentication",
"challenge": "challenge-123",
"jws": "eyJhbGciOiJFZERTQSIsImI2NCI6ZmFsc2UsImNyaXQiOlsiYjY0Il19..iy7fpp3Rqh1aVdslsafvqIFgh3wcPAw7e32_RirFlU8TuzA4AcwUUDe3SQYaP1awBh5kEtRd0ETMzp1Gpzj_CQ"
}
},
"options": {
"challenge": "challenge-123"
}
}'Which should result in a 200:
{
"checks": ["proof"],
"warnings": [],
"errors": []
}We now know how to issue and verify Presentations!