feat: add cns-js library

[nathanosdev]

This has been tested with a TS script as follows:

import { HttpAgent } from '@dfinity/agent';
import { CnsClient } from './cns-client';

async function main(): Promise<void> {
  const agent = HttpAgent.createSync({ host: 'http://localhost:8000' });
  await agent.fetchRootKey();

  const cnsClient = new CnsClient({
    agent,
    cnsRoot: 'bkyz2-fmaaa-aaaaa-qaaaq-cai',
  });

  const icpNamingCanister =
    await cnsClient.lookupNamingCanister('nathanos.icp');
  console.log('.icp naming canister:', icpNamingCanister.toText());

  const nathanosIcpCanister = await cnsClient.lookupCanisterId('nathanos.icp');
  console.log('nathanos.icp canister id:', nathanosIcpCanister.toText());
}

main().catch(console.error);

The CNS Root and TLD Operator were setup and configured with a TLD and domain manually.

[nathanosdev]

This is the main file where the client logic lives, every other file is just boilerplate and less important.

[przydatek]

Would it be possible to add a test for this functionality to CI? (potentially in a follow-up PR)

[nathanosdev]

I opted to make these normalization functions pretty resilient, so you can lookup NC record for any of the following:

• .foo.icp.
• foo.icp.
• foo.icp
• .icp.
• .icp
• icp.

Sub domains like foo.bar.icp should also work with the same variations of . pre/post fixes.

And similarly you can lookup the CID record for any of the following:

• .sub.icp.
• sub.icp.
• sub.icp

[przydatek]

Nice!
nits:

• maybe this function should be a part of utils.ts?
• would it be possible to add some unit tests for this function? (a follow-up PR would be also fine)

[nathanosdev]

This is just a very simple cache that doesn't persist between page loads.

[nathanosdev]

This is just some utils

[nathanosdev]

And the rest is boilerplate nonsense

[przydatek]

LGTM, thanks!

[przydatek]

Would it be possible to add a test for this functionality to CI? (potentially in a follow-up PR)

[przydatek]

Nice!
nits:

• maybe this function should be a part of utils.ts?
• would it be possible to add some unit tests for this function? (a follow-up PR would be also fine)