Error occurred: Error: !signature

Question

I'm trying to create a new SPL token using @solana/web3.js and @solana/spl-token at the end of the process I got this error Error occurred: Error: !signature. Even though I don't know if the weather code is correct or not.

export const getProvider = () => {
  if (typeof window?.solana !== "undefined" && window?.solana?.isPhantom) {
    return window.solana;
  } else {
    throw new Error("Phantom wallet is not available");
  }
};

export const createToken = async () => {
  try {
    console.log("Initializing connection to Solana network...");
    const connectionWallet = new web3.Connection("https://api.devnet.solana.com","confirmed");
    console.log("Connection to Solana network established.");

    console.log("Connecting to Phantom wallet...");
    const account = await window.solana.connect();
    const mintRequester = account?.publicKey;
    console.log("Connected to Phantom wallet.");

    // Connect to the wallet
    console.log("Fetching provider...");
    const provider = await getProvider();
    console.log("Provider fetched successfully.");

    // Get the payer's public key from the wallet
    const payerPublicKey = mintRequester;

    // Generate a new mint account
    console.log("Generating new mint account...");
    const mint = await web3.Keypair.generate();
    console.log("New mint account generated:", mint.publicKey.toString());

    // Construct the token create transaction
    console.log("Constructing token create transaction...");
    const instructions = [
      await splToken.createInitializeMintInstruction(
        mint.publicKey,
        0,
        payerPublicKey,
        null,
        splToken.TOKEN_PROGRAM_ID
      ),
    ];

    // Sign the transaction
    console.log("Signing the transaction...");
    const transaction = await new web3.Transaction().add(...instructions);
    const latestBlockhash = await connectionWallet.getLatestBlockhash();
    transaction.feePayer = payerPublicKey;
    transaction.recentBlockhash = latestBlockhash.blockhash;
    
    console.log("🚀 ~ createToken ~ connectionWallet:", connectionWallet)
    console.log("🚀 ~ createToken ~ connectionWallet:", provider.signTransaction.toString())
    const signedTransaction = await provider.signTransaction(transaction, [
      mint,
    ]);
    console.log("Transaction signed successfully:", signedTransaction);

    // Send the transaction to the network
    console.log("Sending the transaction to the network...");
    const signature = await connectionWallet.sendTransaction(
      signedTransaction,
      [mint]
    );
    console.log("Transaction sent successfully. Signature:", signature);

    // Return the new mint public key
    console.log("New mint public key:", mint.publicKey.toString());
    return mint.publicKey;
  } catch (error) {
    console.error("Error occurred:", error);
  }
};

Answer 1

The error is too vague to debug, but this likely won't work because the mint account isn't getting created before initialization. Try adding one more instruction before createInitializeMintInstruction:

import { getMinimumBalanceForRentExemptMint, MINT_SIZE, TOKEN_PROGRAM_ID } from '@solana/spl-token';
import { Transaction, SystemProgram } from '@solana/web3.js';

    // all other setup code as before

    const mint = Keypair.generate();

    // Get required rent exemption
    const lamports = await getMinimumBalanceForRentExemptMint(connection);

    // Create transaction
    const transaction = new Transaction().add(
        SystemProgram.createAccount({
            fromPubkey: payer.publicKey,
            newAccountPubkey: mint.publicKey,
            space: MINT_SIZE,
            lamports,
            TOKEN_PROGRAM_ID,
        }),
        createInitializeMintInstruction(mint.publicKey, 0, payer, null, TOKEN_PROGRAM_ID)
    );
    // and all other code as before

Adapted from a larger example at https://github.com/solana-labs/solana-program-library/blob/master/token/js/examples/createMintAndTransferTokens.ts and mint creation at https://github.com/solana-labs/solana-program-library/blob/master/token/js/src/actions/createMint.ts