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Working with identities

Generic operations​

Load an Identity​

Use the Identity#at() method to instantiate an Identity from an existing address. This operation supports resolving ENS.

const { IdentitySDK } = require('@onchain-id/identity-sdk');
const provider = ethers.getDefaultProvider('kovan');

const identity = await IdentitySDK.Identity.at('identity.tokeny.xyz', { provider });

Loading an ONCHAINID Contract​

You may need to execute functions or read data from ONCHAINID Contracts that are not exposed by the Identity SDK. The .instantiateAtAddress() method returns a Ethers Contract instance loaded with the full ONCHAINID abi.

const { IdentitySDK } = require('@onchain-id/identity-sdk');

const provider = new IdentitySDK.Providers.JsonRpcProvider();

(async () => {
  const identity = new IdentitySDK.Identity(); // Create the Identity Object

  console.log(identity.instantiateAtAddress('0xadD92F8Ef0729E969c5a98Ea5740c9b644B362e3', { provider })); // Get the instance of the Identity

  console.log(await identity.instance.getClaimIdsByTopic(1)); // Call directly a function from the Contract.
})();

Managing keys​

Keys are addresses (or signing keys) designed as being able to perform operation on or from the Identity. For instance, a wallet registered as a MANAGEMENT Key should be able to manage other keys on the Identity.

In the current implementation, keys are stored as HASH of the key itself. To generate a proper hash for a wallet, use the provided helper method. This is a hidden call to a keccak256 hash of an abi encoded (as defined by Ethereum standard. On a smart contract, the same hash would generated with keccak256(abi.encode(walletAddress)).

const hash = IdentitySDK.utils.encodeAndHash(['address'], [walletAddress]);

Add a purpose to a key or add a new key​

A key is added with a specific purpose. This call will register the key if it doesn't exist yet on the identity contract with the given purpose, or add the purpose to the key if it already exists on the contract. You must also specify the type of the key (ECDSA).

Both key purposes and types have enums you can get from IdentitySDK.utils.enums.

const identity = await Identity.at('<address>', { provider });

const addKeyTransaction = await identity.addKey(IdentitySDK.utils.encodeAndHash(['address'], [walletAddress]), IdentitySDK.utils.enums.KeyPurpose.MANAGEMENT, IdentitySDK.utils.enums.KeyType.ECDSA, { signer });

The signer must be a MANAGEMENT key on the Identity to perform the operation.

Get management keys of an Identity​

import { Identity, IdentitySDK } from "@onchain-id/identity-sdk";
import { ethers } from 'ethers';

(async () => {
    const address = '0x..........' /* address of the identity you want to instanciate */ 
    const provider = ethers.getDefaultProvider('kovan');

    const identity = await Identity.at(address, provider);

    const keys = await identity.getKeysByPurpose(
        IdentitySDK.utils.enums.KeyPurpose.MANAGEMENT
    );
    const hashedAddress = IdentitySDK.utils.encodeAndHash(["address"], ['0x...your wallet address']);
    for (const key of keys) {
        if (key.key === hashedAddress) {
            console.log("The identity has been instantiates we verified the wallet used is a manager of the identity");
        }
    }
})()

Claims​

Add a claim to an identity​

Remember that to add a claim to an identity, the signer of the transaction must have a CLAIM or MANAGEMENT key over the identity.

import { Identity, IdentitySDK } from "@onchain-id/identity-sdk";
import { ethers } from 'ethers';

(async () => {
    const address = '0x..........' /* address of the identity you want to instanciate */
    const provider = ethers.getDefaultProvider('kovan');
    const signer = new ethers.Wallet('private key', provider);

    const identity = await Identity.at(address, signer);

    // prepare the claim
    const claim = new IdentitySDK.Claim({
        address: '/* identity address */',
        data: '/* data of the claim */',
        issuer: '/* issuer address */',
        emissionDate: Date.now(),
        scheme: '/* scheme of the claim */',
        topic: '/* topic of the claim */',
    });

    // sign the claim
    const customSigner = new IdentitySDK.SignerModule({
        publicKey: await signer.getAddress(),
        signMessage: signer.signMessage.bind(this.signer)
    });
    await claim.sign(customSigner);

    // emit the claim
    const tx = await identity.addClaim(claim.topic, claim.scheme, claim.issuer, claim.signature, claim.data, claim.uri, { signer });
    await tx.wait();
})();

Get claims of an Identity​

This method returns only claims that are stored on the ONCHAINID contract. Claims returned might not be valid anymore, so you may need to verify their validity against the Claim Issuer that issued these claims (usually by calling .isClaimValid() on the Claim Issuer contract).

const { IdentitySDK } = require('@onchain-id/identity-sdk');

const provider = ethers.getDefaultProvider('kovan');

(async () => {
    const identity = new IdentitySDK.Identity('0xadD92F8Ef0729E969c5a98Ea5740c9b644B362e3', provider);
    
    const claims = await identity.getClaimsByTopic(109741294);
    
    console.log(claims);
})();