I am using phantom wallet and trying to sign typed data

Question

Hi I am trying to sign a message using solana/wallet-adapter and gets error: "Cannot sign transaction using sign message"

code example below, Solflare and Wallet Connect treats Uint8Array encoded message fine, so trying to figure out

import { serialize } from 'borsh';
const message = new Mail({
from: new Person({
name: 'Cow',
wallet: '0xCD2a3d9F938E13CD947Ec05AbC7FE734Df8DD826'
}),
to: new Person({
name: 'Bob',
wallet: '0xbBbBBBBbbBBBbbbBbbBbbbbBBbBbbbbBbBbbBBbB'
}),
contents: 'Hello, Bob!'
});
// Serialize the data
const serializedData = serialize(schema, message);
// Sign the serialized data
const signature = await phantomWalletProvider.signMessage(serializedData);

this variant doesnt work also:

signature = await walletProvider.signMessage(new TextEncoder().encode(JSON.stringify(message)));

Answer 1

it looks like you have some Ethereum addresses in that message you're signing. Could you please confirm if you're trying to sign a message on Solana? If so, could you please double check that you are passing either a hex or UTF-8 encoded string as a Uint8Array? Phantom's signMessage method on Solana will only accept UTF-8 or hex encoded strings (see docs). For a live example, please see our sandbox and its accompanying signMessage function.