Cosmos SDK transaction signing and verifying

sign.js

const secp256k1 = require('secp256k1');
const bech32 = require('bech32');
const createHash = require('create-hash');
const jsonStringify = require('fast-json-stable-stringify');

function createSigner(privateKey) {
  console.log(`private key: ${privateKey.toString('hex')}`);
  const publicKey = secp256k1.publicKeyCreate(privateKey, true);
  console.log(`public key: ${publicKey.toString('base64')}`);
  const sha256 = createHash('sha256');
  const ripemd = createHash('ripemd160');
  sha256.update(publicKey);
  ripemd.update(sha256.digest());
  const rawAddr = ripemd.digest();
  const cosmosAddress = bech32.encode('cosmos', bech32.toWords(rawAddr));
  console.log(`address: ${cosmosAddress}`);
  const sign = (msg) => {
    const msgSha256 = createHash('sha256');
    msgSha256.update(msg);
    const msgHash = msgSha256.digest();
    const { signature } = secp256k1.sign(msgHash, privateKey);
    console.log(`signature: ${signature.toString('base64')}`);
    return { msgHash, signature, publicKey };
  }
  return { cosmosAddress, sign };
}

const privKey = Buffer.from('0123456789abcdef0123456789abcdef0123456789abcdef0123456789abcdef', 'hex');
const signer = createSigner(privKey);
const signBytes = Buffer.from(jsonStringify({
  "fee": {
    "amount": [
      {
        "denom": "nanolike",
        "amount": "44000000"
      }
    ],
    "gas": "44000"
  },
  "msgs": [
    {
      "type": "cosmos-sdk/MsgSend",
      "value": {
        "from_address": "cosmos1mnyn7x24xj6vraxeeq56dfkxa009tvhgknhm04",
        "to_address": "cosmos1ca0zlqxjqv5gek5qxm602umtkmu88564hpyws4",
        "amount": [
          {
            "denom": "nanolike",
            "amount": "123456789"
          }
        ]
      }
    }
  ],
  "chain_id": "likechain-testnet-taipei-1",
  "account_number": "21",
  "sequence": "0",
  "memo": "",
}), 'utf8');
const { msgHash, signature, publicKey } = signer.sign(signBytes);

// private key: 0123456789abcdef0123456789abcdef0123456789abcdef0123456789abcdef
// public key: A0ZGrlBHMWtCMNAIbIrOxofwCxzZ0dxjT2yzWKwKmo//
// address: cosmos1mnyn7x24xj6vraxeeq56dfkxa009tvhgknhm04
// signature: yXcQvLVEHZMIzZijEgmcL5S7orusBURZoRjWuG1IpoItt5DhY8P9TUaxx31huxV200l6GcEbUlB/Y7jONuf3Bw==

verify.js

const secp256k1 = require('secp256k1');
const createHash = require('create-hash');
const jsonStringify = require('fast-json-stable-stringify');

const signature = Buffer.from('yXcQvLVEHZMIzZijEgmcL5S7orusBURZoRjWuG1IpoItt5DhY8P9TUaxx31huxV200l6GcEbUlB/Y7jONuf3Bw==', 'base64');
const publicKey = Buffer.from('A0ZGrlBHMWtCMNAIbIrOxofwCxzZ0dxjT2yzWKwKmo//', 'base64');
const msg = jsonStringify({
  "fee": {
    "amount": [
      {
        "denom": "nanolike",
        "amount": "44000000"
      }
    ],
    "gas": "44000"
  },
  "msgs": [
    {
      "type": "cosmos-sdk/MsgSend",
      "value": {
        "from_address": "cosmos1mnyn7x24xj6vraxeeq56dfkxa009tvhgknhm04",
        "to_address": "cosmos1ca0zlqxjqv5gek5qxm602umtkmu88564hpyws4",
        "amount": [
          {
            "denom": "nanolike",
            "amount": "123456789"
          }
        ]
      }
    }
  ],
  "chain_id": "likechain-testnet-taipei-1",
  "account_number": "21",
  "sequence": "0",
  "memo": "",
})
const msgSha256 = createHash('sha256');
msgSha256.update(msg);
const msgHash = msgSha256.digest();
console.log(secp256k1.verify(msgHash, signature, publicKey));