永久委派擴展
PermanentDelegate 擴展是一個鑄幣賬戶擴展,允許為該鑄幣的所有代幣設置一個永久委派,該委派可以從任何代幣賬戶轉移或銷毀該鑄幣的任何代幣。
初始化鑄幣賬戶
要在 Mint 賬戶上初始化 PermanentDelegate 擴展,我們需要使用 initializePermanentDelegate() 函數。
以下是如何使用永久委派擴展創建鑄幣的方法:
ts
import {
Keypair,
SystemProgram,
Transaction,
sendAndConfirmTransaction,
} from '@solana/web3.js';
import {
createInitializeMintInstruction,
createInitializePermanentDelegateInstruction,
getMintLen,
ExtensionType,
TOKEN_2022_PROGRAM_ID,
} from '@solana/spl-token';
const mint = Keypair.generate();
// Calculate the size needed for a Mint account with Permanent Delegate extension
const mintLen = getMintLen([ExtensionType.PermanentDelegate]);
// Calculate minimum lamports required for rent exemption
const lamports = await connection.getMinimumBalanceForRentExemption(mintLen);
// Create the account with the correct size and owner
const createAccountInstruction = SystemProgram.createAccount({
fromPubkey: keypair.publicKey,
newAccountPubkey: mint.publicKey,
space: mintLen,
lamports,
programId: TOKEN_2022_PROGRAM_ID,
});
// Initialize the Permanent Delegate extension
const initializePermanentDelegate = createInitializePermanentDelegateInstruction(
mint.publicKey,
keypair.publicKey,
TOKEN_2022_PROGRAM_ID,
);
// Initialize the mint itself
const initializeMintInstruction = createInitializeMintInstruction(
mint.publicKey,
6,
keypair.publicKey,
null,
TOKEN_2022_PROGRAM_ID,
);
// Combine all instructions in the correct order
const transaction = new Transaction().add(
createAccountInstruction,
initializePermanentDelegate,
initializeMintInstruction,
);
const signature = await sendAndConfirmTransaction(connection, transaction, [keypair, mint]);
console.log(`Mint created! Check out your TX here: https://explorer.solana.com/tx/${signature}?cluster=devnet`);關閉鑄幣賬戶
如果 Mint 賬戶的供應量為零,CloseMint Authority 可以通過使用 closeAccount 指令來回收該賬戶的租金,如下所示:
ts
const closeMintInstruction = createCloseAccountInstruction(
mint.publicKey,
keypair.publicKey,
keypair.publicKey,
[],
TOKEN_2022_PROGRAM_ID,
);
const transaction = new Transaction().add(closeMintInstruction);
const signature = await sendAndConfirmTransaction(connection, transaction, [keypair], {skipPreflight: false});
console.log(`Mint closed! Check out your TX here: https://explorer.solana.com/tx/${signature}?cluster=devnet`);有權限的操作
與可以被撤銷的普通委派不同,這種委派權限是永久且不可更改的。
這意味著每個普通操作,例如 transfer()、burn()、approve() 和 freeze(),都可以在需要時由權限直接執行,而無需實際擁有者的簽名。
這意味著我們可以直接使用普通的 transferChecked()、burnChecked() 等指令,並在 authority 欄位中傳入 PermanentDelegate 權限。