Request NFT
In some cases, you may need check if your DID Wallet has specific NFT or VC, like if you've been to ArcBlock devcon 2021, follow this article to learn how to request some NFT or VC with DID Connect.
The basic process is consistent with the "Quick Start" chapter, change the code in the handler as follows:
const { fromPublicKey } = require('@ocap/wallet');
const { toAddress, fromBase58, toBuffer } = require('@ocap/util');
const { toTypeInfo } = require('@arcblock/did');
const { verifyAssetClaim } = require('../../libs/utils');
const { wallet } = require('../../libs/auth');
const logger = require('../../libs/logger');
const validateAgentProof = (claim) => {
const ownerDid = toAddress(claim.ownerDid);
const ownerPk = fromBase58(claim.ownerPk);
if (!claim.agentProof) {
throw new Error('agent proof is empty');
}
if (typeof claim.agentProof === 'string') {
claim.agentProof = JSON.parse(claim.agentProof);
}
logger.info('claim.agentProof.nonce', claim.agentProof.nonce);
logger.info('claim.agentProof.signature', claim.agentProof.signature);
const { nonce } = claim.agentProof;
if (nonce < Math.ceil(Date.now() / 1000) - 5 * 60) {
throw new Error('agent proof is expired: ttl is 5 minutes');
}
const message = Buffer.concat([toBuffer(nonce.toString()), toBuffer(wallet.address)]);
const signer = fromPublicKey(ownerPk, toTypeInfo(ownerDid));
const signature = fromBase58(claim.agentProof.signature);
if (claim.type === 'asset') {
if (!signer.verify(message, signature)) {
throw new Error('agent proof is invalid for asset');
}
}
if (claim.type === 'verifiableCredential') {
if (!signer.verify(message, signature)) {
throw new Error('agent proof is invalid for vc');
}
}
};
const action = 'request-nft';
module.exports = {
action,
onConnect() {
return {
assetOrVC: () => {
return {
description: 'Please provide NFT or VC to continue',
filters: [
{
type: ['NFTBadge', 'NFTCertificate'],
trustedIssuers: [
// wallet.address,
'zNKXAEjKYXEnf2hf18NjTQsa1JajA9gJ3haY',
],
},
],
};
},
};
},
onAuth: async ({ claims, challenge, updateSession }) => {
const asset = claims.find((x) => x.type === 'asset');
if (!asset) {
throw new Error('Neither NFT nor VC is provided');
}
logger.info(`${action}.onAuth.asset`, asset);
validateAgentProof(asset, challenge);
const assetState = await verifyAssetClaim({ claim: asset, challenge });
updateSession({
result: asset,
});
return { successMessage: `You provided asset: ${assetState.address}` };
},
};
Change the front-end part calling the DID Connect code to the following:
connectApi.open({
locale: 'en',
action: 'request-nft',
onSuccess({ result }) {
// NFT data will be in result
},
messages: {
title: 'Request NFT',
scan: 'Please provide a NFT to continue',
},
});