Test eth_signTypedData

test.js

import signUtil from "eth-sig-util"

const getLoginTypedData = ({ address, timestamp, primaryType }) => ({
  types: {
    EIP712Domain: [
      { name: 'name', type: 'string' },
      { name: 'host', type: 'string' },
      { name: 'version', type: 'string' },
    ],
    WebLogin: [
      { name: 'address', type: 'address' },
      { name: 'timestamp', type: 'uint256' },
    ],
  },
  domain: {
    name: 'Wallet web',
    host: 'https://wallet.matic.network',
    version: '1',
  },
  primaryType,
  message: {
    address,
    timestamp,
  },
})

// Sign Message

const signedMsg = sigUtil.signTypedData(privKeybuffer, {
  data: getLoginTypedData({ address, timestamp, primaryType: 'WebLogin' }),
})


// recover from signedMessage
const recovered = signUtil.recoverTypedSignature({
  data: getLoginTypedData(address, timestamp),
  sig: signedMessage
})

if (recovered && recovered === address) {
  console.log("valid")
}