@decentraweb/namekit v2.5.2

Decentraweb Namekit

Namekit package intended to allow app developers to seamlessly integrate decentralized name systems into their apps. Right now it has support for ENS, Decentraweb and limited support of classic DNS system.

For now Namekit only support reading data. If you need to manage domain data, please check @decentraweb/core or one of ENS libraries.

Domain resolution logic

Domain name provider is detected using following logic: 1. If domain name ends with .eth then it is resolved through ENS 2. If domain name TLD match one of the ICANN TLDs, then it is resolved through regular DNS. 3. All other domains are resolved with DWEB contracts.

List of ICANN domains can be found here and is updated regulary.

Important Note: This logic may change in the future.

Installation and initialization

To install library run npm install --save @decentraweb/namekit ethers@5 in your project directory.

Namekit uses ethers.js to call Ethereum contracts. It is required as peer dependency.

Decentraweb supports both Ethereum and Polygon networks. Namekit will automatically detect which network to use based on where domain name is located currently. To initialize Namekit instance you need to pass Ethereum and Polygon network name (mainnet is used with 'matic' and goerli is used with 'maticmum') and ethers.js providers for each network.

import {providers, Wallet} from "ethers";
import DwebNamekit, {NamekitConfig} from "@decentraweb/namekit";

const ETH_NETWORK = 'goerli';
const ETH_JSONRPC_URL = 'https://goerli.infura.io/v3/00000000000000000000000000000000';
const POLYGON_NETWORK = 'maticmum';
const POLYGON_JSONRPC_URL = 'https://polygon-mumbai.infura.io/v3/00000000000000000000000000000000';
const config: NamekitConfig = {
  ethereum: {
    network: ETH_NETWORK,
    provider: new providers.JsonRpcProvider(ETH_JSONRPC_URL, ETH_NETWORK),
  },
  polygon: {
    network: POLYGON_NETWORK,
    provider: new providers.JsonRpcProvider(POLYGON_JSONRPC_URL, POLYGON_NETWORK)
  }
};
const namekit = new DwebNamekit(config);

Alternatively, if you use one of supported providers, you can initialize Namekit in a simpler way:

const config: NamekitConfig = {
  apiProvider: 'infura', //Supported providers: 'etherscan', 'infura', 'alchemy', 'cloudflare', 'pocket', 'ankr'
  apiKey: '00000000000000000000000000000000', //
  production: false //If true, then mainnet and matic networks will be used, otherwise goerli and maticmum
};
const namekit = new DwebNamekit(config);

Browser bundle

In most cases importing library using npm is preferred way, but for fast prototyping you can load it from our CND:

<script src="https://cdn.ethers.io/lib/ethers-5.7.umd.min.js" type="application/javascript"></script>
<script src="https://cdn.decentraweb.org/decentraweb-namekit-2.2.2.min.js" type="application/javascript"></script>
<script>
  window.addEventListener('load', async () => {
    const {DwebNamekit} = Decentraweb;
    const namekit = new DwebNamekit({
      ethereum: {
        network: 'mainnet',
        provider: ethers.getDefaultProvider('mainnet')
      },
      polygon: {
        network: 'matic',
        provider: ethers.getDefaultProvider('matic')
      }
    })
</script>

Resolve Ethereum address to name

Ethereum address can be resolved through both Decentraweb and ENS contracts or through one specified system.

const names = await namekit.address.resolve('0x4323E6b155BCf0b25f8c4C0B37dA808e3550b521');
/*
Returns:
[
  { provider: 'dweb', name: 'vitalik' },
  { provider: 'ens', name: 'vitalik.eth' }
]
*/
//To query Decentraweb only
const dwebName = await namekit.address.resolve('0x4323E6b155BCf0b25f8c4C0B37dA808e3550b521', 'dweb');
/*
Returns: 'vitalik'
*/
// Alternatively to query ENS
const ensName = await namekit.address.resolve('0x4323E6b155BCf0b25f8c4C0B37dA808e3550b521', 'ens');
/*
Returns: 'vitalik.eth'
*/

Resolve name to Ethereum address

In this case Namekit will detect which domain name system name belongs to and will look for Ethereum address associated with given name. Note that classic domains will always return null.

const address = await namekit.address.lookup('vitalik');
/*
Returns: '0x4323E6b155BCf0b25f8c4C0B37dA808e3550b521'
*/

Reading extended domain data

By calling namekit.domain(domainName) you can get instance of class that will allow to read extended data associated with domain name. Depending on domain name provider you will get either DWEBDomain, ENSDomain or ICANNDomain instance. Below you can see feature support table for different domain name systems.

1. supported through DNSLink

const domain = await namekit.domain('vitalik');
if (domain) {
  const domainProvider = domain.provider; // 'ens'
  const ethAddress = await domain.address('ETH'); // '0x4323E6b155BCf0b25f8c4C0B37dA808e3550b521'
  const contentHash = await domain.contentHash(); // 'ipfs://bafybeiaysi4s6lnjev27ln5icwm6tueaw2vdykrtjkwiphwekaywqhcjze'
  const githubName = await domain.txt('email'); // 'foo@bar.baz'
  const records = await domain.dns('A'); // [{ name: 'vitalik', type: 'A', ttl: 3600, class: 'IN', data: '127.0.0.1'}]
}

Domain name

All domain name wrapper classes (DWEBDomain, ENSDomain and ICANNDomain) have same interface to provide consistent API for developers.

interface BaseDomain {
  //Domain name
  readonly name: string;
  //Which domain name system is used to query the data
  readonly provider: 'dweb' | 'ens' | 'icann';
  //Supported features for domain
  readonly features: {
    address: boolean;
    contentHash: boolean;
    dns: boolean;
    txt: boolean;
  };

  //Get cryptocurrency address for given coinId
  address(coinId: string): Promise<string | null>;

  //Get contenthash associated with domain name
  contentHash(): Promise<string | null>;

  //Get DNS records of given type. Response contains JSON representation of records
  dns(recordType: string): Promise<dnspacket.Answer[]>;

  //Check if domain name is registered
  exists(): Promise<boolean>;

  //Read text records on domain
  txt(key: string): Promise<string | null>;
}

Notes: 1. Full list of supported cryptocurrencies can be found in @ensdomains/address-encoder documentation. 2. Unsupported feature methods will always return null and won't throw an error. 3. There is no reliable way to check if domain name is registered for classic DNS. Because of this domain.exists() will always return true for icann domains.
4. DNS records are stored in binary format. This library uses dns-packet library to encode/decode data.