Extension Wallet
Integration
APTOS Network
Sign Message

Sign Message

Cosmostation supports message signing via the Aptos Wallet Adapter and the Aptos Wallet Standard.

Message signing is commonly used for off-chain use cases where you need to prove wallet ownership without submitting an on-chain transaction.

Typical examples include:

  • Wallet-based login / authentication
  • User consent or approval flows
  • Linking a wallet address to an off-chain account
  • Generating verifiable signatures for backend validation

Using Aptos Wallet Adapter

When using @aptos-labs/wallet-adapter-react, you can request a message signature through signMessage().

The wallet will display a confirmation UI showing the message content, and the user must explicitly approve the request.

Example

import { useWallet } from '@aptos-labs/wallet-adapter-react';
 
const { account, connected, signMessage, signMessageAndVerify } = useWallet();
 
const messageForSign = 'Hello from Cosmostation';
 
const onSignMessage = async () => {
  if (!connected || !account) return;
 
  try {
    const payload = {
      message: messageForSign,
      nonce: generateNonce(),
    };
 
    const response = await signMessage(payload);
    console.log('sign message response:', response);
  } catch (error) {
    console.error(error);
  }
};
 
const onSignMessageAndVerify = async () => {
  if (!connected || !account) return;
 
  try {
    const payload = {
      message: messageForSign,
      nonce: generateNonce(),
    };
 
    const response = await signMessageAndVerify(payload);
    console.log('sign message and verify response:', response);
  } catch (error) {
    console.error(error);
  }
};

Notes

  • Always include a nonce (and optionally a timestamp) to prevent replay attacks
  • The signed message is not broadcast on-chain
  • The returned signature can be verified off-chain using the account’s public key

Demo / Reference Implementation

You can see a working example of message signing in the official adapter demo:

Vanilla Code

Cosmostation also exposes signMessage directly through the injected provider, without requiring any adapter libraries.

The vanilla API follows the Aptos Wallet Standard – AptosSignMessageMethod.

Example

const payload: AptosSignMessageInput = {
  message: 'Hello from Cosmostation',
  nonce: generateNonce(),
};
 
try {
  const provider = aptos();
  const response = await provider.signMessage(payload);
 
  console.log('signMessage response:', response);
} catch (e: any) {
  if (e?.code === 4001) {
    console.log('user rejected request');
  } else {
    console.error(e);
  }
}

Spec Reference

If you need the exact input and output type definitions for signMessage, refer to the Aptos Wallet Standard source:

Sign & Submit TransactionNetwork