Epnsfrontendsubscribe

import {channels} from '@epnsproject/frontend-sdk-staging';
import {ethers} from 'ethers';
import Web3Modal from 'web3modal';
    
const web3Modal = new Web3Modal();
const connection = await web3Modal.connect();
const provider = new ethers.providers.Web3Provider(connection);
const signer = provider.getSigner();

const epnsSubscribe = async () => {
     await channels.optIn(
         signer,
         channelAddress,
         chainId,
         userAddress,
         {
            onSuccess: () =>  // do something after success
         }
     );
};

const epnsUnSubscribe = async () => {
     await channels.optOut(
         signer,
         channelAddress,
         chainId,
         userAddress,
         {
            onSuccess: () =>  // do something after success
         }
     )
};