Error with account type in aptos.transaction.sign

[MartinYeung5]

Hi team, i tried to use aptos.transaction.sign,

The following is my code:
import { useWallet } from "@aptos-labs/wallet-adapter-react";
const { account, signAndSubmitTransaction } = useWallet();
const owner1 = account;

const bobSenderAuthenticator = aptos.transaction.sign({
signer: owner1 ,
transaction,
});

version:
"@aptos-labs/ts-sdk": "^1.26.0",
"@aptos-labs/wallet-adapter-react": "^3.4.3",

When i get the account data from wallet, i can't use in aptos.transaction.sign.
The console showed the error msg:
TypeError: a.signTransactionWithAuthenticator is not a function

if i use:
let owner2 = Account.generate();
const bobSenderAuthenticator = aptos.transaction.sign({
signer: owner2 ,
transaction,
});

results:
no error

Therefore, how can i change the account type to Ed25519Account ?

[0xmaayan]

Hi @MartinYeung5 !

To sign a transaction, you must provide the signer/wallet private key so it can be used to sign the transaction with.

When you try to do it with the info the wallet adapter provides, you wont succeed as the wallet adapter NEVER exposes the wallet private key (for obvious security reasons), so

const { account } = useWallet();

only returns the public wallet info such as the account address, public key, etc. Because of that, when you provide that argument to the SDK sign method, you are getting an error (not sure if you use TypeScript but you should get a type error when trying to pass a different type to that function).

On the other hand, when you generate a new account with let owner2 = Account.generate(); that account type holds the private key and when you are passing it to the SDK sign method it succeeds.

Not sure what the exact flow you are trying to achieve,

• If you only want to sign and submit transaction in a one go, you could use signAndSubmitTransaction method from the useWallet() provider.
• If you want to just sign a transaction using the SDK aptos.transaction.sign method, then you would need to know the signer private key and build an Account out of it

const privateKey = new Ed25519PrivateKey("0xc533...fa5");
const account = Account.fromPrivateKey({ privateKey });
const bobSenderAuthenticator = aptos.transaction.sign({
  signer: account,
  transaction,
});

[MartinYeung5]

thanks for your reply with detailed explanation,
but if i want to let user to do the sign action, how can i do ?
Actually, i can't get the user privatekey