Sign Message

Cosmostation’s Sui wallet supports message signing through the Sui wallet standard. This is useful when you need a user-approved signature for an off-chain flow (e.g., wallet login, account linking, or acknowledging a statement) without submitting an on-chain transaction.

Cosmostation supports both message-signing feature keys:

sui:signMessage (v1)
sui:signPersonalMessage (v2)

In most Sui dApps, the recommended approach is to use Sui dApp Kit and its wallet hooks.

Using Sui dApp Kit (`useSignPersonalMessage`)

Sui dApp Kit provides the useSignPersonalMessage hook to prompt the user to sign a message with their wallet. The hook takes a message as Uint8Array, and returns:

signature: Base64-encoded signature string
bytes: Base64-encoded message bytes

Example (React)

import { ConnectButton, useCurrentAccount, useSignPersonalMessage } from '@mysten/dapp-kit';
import { useState } from 'react';
 
export function SignMessageExample() {
  const { mutate: signPersonalMessage } = useSignPersonalMessage();
  const currentAccount = useCurrentAccount();
 
  const [message, setMessage] = useState('Hello from Cosmostation');
  const [signature, setSignature] = useState('');
 
  return (
    <div style={{ padding: 20 }}>
      <ConnectButton />
 
      {currentAccount && (
        <>
          <div>
            <label>
              Message:{' '}
              <input type="text" value={message} onChange={(ev) => setMessage(ev.target.value)} />
            </label>
          </div>
 
          <button
            onClick={() => {
              signPersonalMessage(
                { message: new TextEncoder().encode(message) },
                {
                  onSuccess: (result) => setSignature(result.signature),
                },
              );
            }}
          >
            Sign message
          </button>
 
          <div>Signature: {signature}</div>
        </>
      )}
    </div>
  );
}

Key points

message must be provided as Uint8Array ([Mysten Labs TypeScript SDK Docs][1])
chain is optional; if omitted, it defaults to the active network configured in the dApp (Mysten Labs TypeScript SDK Docs (opens in a new tab))
The wallet returns both signature and bytes as Base64 strings (Mysten Labs TypeScript SDK Docs (opens in a new tab))

Vanilla JavaScript (Cosmostation Extension)

If you are not using @mysten/dapp-kit, you can call the injected provider directly.

Cosmostation’s internal implementation serializes message bytes as Base64 before sending the request to the extension app-layer (so transport stays consistent across contexts). In practice, your dApp can pass a string or bytes, and the provider will handle the encoding step.

`sui:signMessage` (v1)

await window.cosmostation.sui.connect();
 
const res = await window.cosmostation.sui.signMessage({
  message: 'Hello from Cosmostation',
  // account: optional (wallet-selected account is typically used)
});
 
console.log('signMessage:', res);

`sui:signPersonalMessage` (v2)

await window.cosmostation.sui.connect();
 
const res = await window.cosmostation.sui.signPersonalMessage({
  message: 'Hello from Cosmostation',
  // account: optional (wallet-selected account is typically used)
});
 
console.log('signPersonalMessage:', res);

Sign & Execute Transaction Event