永久委托扩展
PermanentDelegate
扩展是一个 Mint account 扩展,允许为该 mint 的所有代币设置一个永久委托,该委托可以从任何 token account 转移或销毁该 mint 的任何代币。
初始化 Mint Account
要在 Mint
账户上初始化 PermanentDelegate
扩展,我们需要使用 initializePermanentDelegate()
函数。
以下是如何创建带有 Mint Close 扩展的 mint:
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 Transfer Fee extension
const mintLen = getMintLen([ExtensionType.MintCloseAuthority]);
// 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/${signature}?cluster=devnet`);
关闭 Mint Account
如果 Mint
账户的供应量为零,CloseMint Authority
可以通过使用 closeAccount
指令来回收该账户的 rent,如下所示:
const closeMintInstruction = createCloseAccountInstruction(
mint.publicKey,
keypair.publicKey,
keypair.publicKey,
[],
TOKEN_2022_PROGRAM_ID,
);
const transaction = new Transaction().add(closeMintInstruction);
const signature = await sendAndConfirmTransaction(connection, transaction, [keypair], {skipPreflight: false});
console.log(`Mint closed! Check out your TX here: https://explorer.solana.com/tx/${signature}?cluster=devnet`);
权限操作
与可以被撤销的普通委托不同,这种委托权限是永久且不可更改的。
这意味着每个常规操作,例如 transfer()
、burn()
、approve()
和 freeze()
,都可以在需要时直接由权限方执行,而无需实际所有者的签名。
这意味着我们可以直接使用常规的 transferChecked()
、burnChecked()
等指令,并在 authority
字段中传入 PermanetDelegate
权限。