Message Signing and Wallet Balance

This section demonstrates how to sign arbitrary messages (for authentication, proof-of-ownership, etc.) and retrieve wallet balances using the WalletConnector SDK.

Both features are essential in many dApps — message signing for login and wallet verification, and balance checking for enabling or disabling actions based on token/ETH holdings.

🧱 1. Framework Usage (ES6/Module Bundlers)

📁 Installation

If you haven’t already:

npm install multichain-wallet-connector

Or if you use Yarn:

yarn add multichain-wallet-connector

🖊️ A. Sign Message Example

Here's a minimal setup for connecting to a wallet and signing a transaction:

import { connectWallet, signMessage } from 'multichain-wallet-connector';

let provider, account;

async function connect() {
  const res = await WalletConnector.connectWallet({ chainId: 1 });//Replace with your chainId
  provider = res.provider;
  account = res.account;
}

async function signMessage() {
  if (!provider || !account) await connect();

  const message = "Please sign this message to verify wallet ownership.";
  const signature = await WalletConnector.signMessage(provider, account, message);

  console.log('Signed Message:', signature);
}

For typescript users, declare as a module in your types file:

declare module 'multichain-wallet-connector';

🧠 Use Case: Message signing is commonly used for user authentication (e.g., login with wallet) without needing private key exposure or gas fees.

💰 B. Fetch Wallet Balance

async function getBalance() {
  if (!provider || !account) await connect();

  try {
    const balance = await WalletConnector.getBalance(provider, account);
    console.log('Wallet Balance:', balance);
  } catch (error) {
    console.error('Failed to get balance:', error);
  }
}

🌐 2. CommonJS via CDN (HTML/Vanilla JS)

✅ Embed Script

<script src="https://cdn.jsdelivr.net/gh/Nworah-Gabriel/multichain-wallet-connector@v1.0.3/dist/connector.umd.min.js"></script>

Ensure this is added before your custom scripts in the HTML body.

🖊️ A. Sign Message Example (CDN)

<script>
  let provider, account;

  async function connect() {
    const res = await WalletConnector.connectWallet({ chainId: 1 });//Replace with your chainId
    provider = res.provider;
    account = res.account;
  }

  async function SignMessage() {
    if (!provider || !account) await connect();

    const message = "Sign this message to continue";
    const signature = await WalletConnector.signMessage(provider, account, message);

    console.log("Message Signature:", signature);
  }
</script>

<button onclick="SignMessage()">Sign Message</button>

⚠️ Signed messages do not incur gas fees. They’re purely cryptographic and used for validation or proof of identity.

⚙️ Error Handling (Recommended)

For production readiness, always wrap async calls with try/catch:

try {
  const signature = await WalletConnector.signMessage(provider, account, message);
} catch (error) {
  console.error("Signing failed:", error.message);
}

📚 Summary

Feature	Method	Gas Required	Use Case
Sign Message	signMessage(provider, account, '<message>')	❌ No	Auth, proof of ownership
Get Balance	getBalance(provider, account)	❌ No	Display balance, condition UI flows