元数据指针与代币元数据

什么是元数据指针和代币元数据扩展?

Token Extensions Program 的 MetadataPointer 铸币扩展在铸币上存储两个字段:

  • 可以更新指针的权限
  • 存储代币元数据的账户地址

该指针可以引用任何实现了 token-metadata 接口的程序所拥有的账户。

Token Extensions Program 还通过 TokenMetadata 铸币扩展直接实现了相同的接口。使用 TokenMetadata,铸币会将代币的 name、symbol、uri、update_authority 以及自定义元数据直接存储在铸币账户本身上。

链下元数据 URI

uri 字段指向链下 JSON 元数据。请参见链下元数据格式。

这两个扩展解决不同的问题:

  • MetadataPointer 指定存储元数据的账户。
  • TokenMetadata 将元数据直接存储在铸币账户上。

可变长度扩展

TokenMetadata 是一个可变长度的 TLV 扩展。 InitializeTokenMetadata、UpdateField 和 RemoveKey 可以调整铸币账户数据的大小,但它们不会转移额外的 lamport。 铸币账户需要足够的 lamport 来保持存储的元数据免于租金。如果元数据稍后增长,需要在调整大小的指令之前向铸币账户转移额外的 lamport。

如何在铸币账户上存储代币元数据

要在铸币账户上存储元数据:

  1. 计算铸币账户大小以及铸币、扩展和元数据所需的租金。
  2. 使用 CreateAccount 创建铸币账户,初始化 MetadataPointer,并使用 InitializeMint 初始化铸币。
  3. 在铸币账户上初始化 TokenMetadata,然后使用 UpdateField 添加或更新元数据。
  4. 使用 RemoveKey、UpdateAuthority 和 Emit 来删除自定义元数据、更改或清除更新权限,或在交易返回数据中返回当前元数据。

计算账户大小

计算基础铸币加上 MetadataPointer 扩展的铸币账户大小。这是在 CreateAccount 中使用的大小。

计算租金

在 TokenMetadata 存储到铸币账户后,使用所需的最大大小计算租金。

创建铸币账户

使用计算出的空间和 lamport 创建铸币账户。

初始化元数据指针

初始化 MetadataPointer 并将其元数据地址设置为铸币地址。

初始化铸币

在同一交易中使用 InitializeMint 初始化铸币。

初始化和更新元数据

在铸币账户上初始化 TokenMetadata。使用 UpdateField 添加自定义元数据;如果该字段不存在,UpdateField 会添加它。

更新、删除或发出元数据

铸币初始化后,使用 UpdateField 更新元数据,使用 UpdateMetadataPointer 更新元数据指针,使用 RemoveKey 删除自定义元数据,使用 UpdateAuthority 清除更新权限,并使用 Emit 返回当前元数据。

计算账户大小

计算基础铸币加上 MetadataPointer 扩展的铸币账户大小。这是在 CreateAccount 中使用的大小。

计算租金

在 TokenMetadata 存储到铸币账户后,使用所需的最大大小计算租金。

创建铸币账户

使用计算出的空间和 lamport 创建铸币账户。

初始化元数据指针

初始化 MetadataPointer 并将其元数据地址设置为铸币地址。

初始化铸币

在同一交易中使用 InitializeMint 初始化铸币。

初始化和更新元数据

在铸币账户上初始化 TokenMetadata。使用 UpdateField 添加自定义元数据;如果该字段不存在,UpdateField 会添加它。

更新、删除或发出元数据

铸币初始化后,使用 UpdateField 更新元数据,使用 UpdateMetadataPointer 更新元数据指针,使用 RemoveKey 删除自定义元数据,使用 UpdateAuthority 清除更新权限,并使用 Emit 返回当前元数据。

Example
const client = await createClient()
.use(generatedPayer())
.use(
solanaRpc({
rpcUrl: "http://localhost:8899",
rpcSubscriptionsUrl: "ws://localhost:8900"
})
)
.use(rpcAirdrop())
.use(airdropPayer(lamports(1_000_000_000n)));
const mint = await generateKeyPairSigner();
const metadataPointerExtension = extension("MetadataPointer", {
authority: client.payer.address,
metadataAddress: mint.address
});
const mintSpace = BigInt(getMintSize([metadataPointerExtension]));

指令顺序

MetadataPointerInstruction::Initialize 必须在 InitializeMint 之前执行。CreateAccount、 MetadataPointerInstruction::Initialize 和 InitializeMint 必须 包含在同一个交易中。

源代码参考

元数据指针

项目描述源代码
MetadataPointer存储元数据指针权限和元数据账户地址的铸币扩展。源代码
MetadataPointerInstruction::Initialize在 InitializeMint 之前初始化元数据指针扩展。源代码
MetadataPointerInstruction::Update更新铸币的元数据指针扩展中存储的元数据地址。源代码
process_initialize (MetadataPointer)元数据指针处理器逻辑,初始化时至少需要一个权限或元数据地址。源代码
process_update (MetadataPointer)验证元数据指针权限,然后重写铸币中存储的元数据地址。源代码

代币元数据

项目描述源代码
TokenMetadata存储在 TLV 条目中的可变长度代币元数据接口状态。源代码
Field由 UpdateField 使用的字段枚举,用于定位 name、symbol、uri 或自定义键。源代码
TokenMetadataInstruction::Initialize初始化代币元数据账户的基本 name、symbol 和 uri 字段。源代码
TokenMetadataInstruction::UpdateField在代币元数据上添加或更新基本字段或自定义元数据字段。源代码
TokenMetadataInstruction::RemoveKey删除自定义元数据键。无法使用此指令删除基本字段。源代码
TokenMetadataInstruction::UpdateAuthority轮换元数据更新权限,或完全清除它以使元数据不可变。源代码
TokenMetadataInstruction::Emit通过交易返回数据返回序列化的元数据,可选择指定字节范围。源代码
process_initialize (TokenMetadata)代币元数据处理器逻辑,要求元数据账户必须是铸币本身,且铸币必须具有 MetadataPointer。源代码
process_update_field在字段更新后重新分配并重写可变长度的 TokenMetadata TLV 条目。源代码
process_remove_key验证更新权限,删除自定义元数据键,并重写 TLV 条目。源代码
process_update_authority验证当前更新权限,然后就地轮换或清除元数据权限。源代码
process_emit从铸币中读取序列化的 TokenMetadata,并将请求的片段写入返回数据。源代码

Typescript

下面的 Kit 示例直接使用生成的指令。使用 @solana/web3.js、@solana/spl-token 和 @solana/spl-token-metadata 的旧版示例仅供参考。旧版示例将 maxSupportedTransactionVersion 上限设为 0,因为 web3.js v1 无法反序列化 v1 交易。

Kit

Instructions
import {
lamports,
createClient,
generateKeyPairSigner,
unwrapOption
} from "@solana/kit";
import { solanaRpc, rpcAirdrop } from "@solana/kit-plugin-rpc";
import { generatedPayer, airdropPayer } from "@solana/kit-plugin-signer";
import { unpack as unpackTokenMetadata } from "@solana/spl-token-metadata";
import { getCreateAccountInstruction } from "@solana-program/system";
import {
extension,
fetchMint,
getEmitTokenMetadataInstruction,
getInitializeMetadataPointerInstruction,
getInitializeMintInstruction,
getInitializeTokenMetadataInstruction,
getMintSize,
getRemoveTokenMetadataKeyInstruction,
getUpdateMetadataPointerInstruction,
getUpdateTokenMetadataFieldInstruction,
getUpdateTokenMetadataUpdateAuthorityInstruction,
isExtension,
tokenMetadataField,
TOKEN_2022_PROGRAM_ADDRESS
} from "@solana-program/token-2022";
const client = await createClient()
.use(generatedPayer())
.use(
solanaRpc({
rpcUrl: "http://localhost:8899",
rpcSubscriptionsUrl: "ws://localhost:8900"
})
)
.use(rpcAirdrop())
.use(airdropPayer(lamports(1_000_000_000n)));
const mint = await generateKeyPairSigner();
const metadataPointerExtension = extension("MetadataPointer", {
authority: client.payer.address,
metadataAddress: mint.address
});
const mintSpace = BigInt(getMintSize([metadataPointerExtension]));
const maxTokenMetadataExtension = extension("TokenMetadata", {
updateAuthority: client.payer.address,
mint: mint.address,
name: "Example Token v2",
symbol: "EXMPL",
uri: "https://example.com/token.json",
additionalMetadata: new Map([
["description", "Metadata stored on mint account"]
])
});
const maxMintSpace = BigInt(
getMintSize([metadataPointerExtension, maxTokenMetadataExtension])
);
const mintRent = await client.rpc
.getMinimumBalanceForRentExemption(maxMintSpace)
.send();
await client.sendTransaction([
getCreateAccountInstruction({
payer: client.payer, // Account funding account creation.
newAccount: mint, // New mint account to create.
lamports: mintRent, // Lamports funding the mint account rent.
space: mintSpace, // Account size in bytes for the mint plus MetadataPointer.
programAddress: TOKEN_2022_PROGRAM_ADDRESS // Program that owns the mint account.
}),
getInitializeMetadataPointerInstruction({
mint: mint.address, // Mint account that stores the MetadataPointer extension.
authority: client.payer.address, // Authority allowed to update the metadata pointer later.
metadataAddress: mint.address // Account address that stores the metadata.
}),
getInitializeMintInstruction({
mint: mint.address, // Mint account to initialize.
decimals: 0, // Number of decimals for the token.
mintAuthority: client.payer.address, // Authority allowed to mint new tokens.
freezeAuthority: client.payer.address // Authority allowed to freeze token accounts.
}),
getInitializeTokenMetadataInstruction({
metadata: mint.address, // Mint account that stores the metadata.
updateAuthority: client.payer.address, // Authority allowed to update metadata later.
mint: mint.address, // Mint that the metadata describes.
mintAuthority: client.payer, // Signer authorizing metadata initialization for the mint.
name: "Example Token", // Token name stored in metadata.
symbol: "EXMPL", // Token symbol stored in metadata.
uri: "https://example.com/token.json" // URI pointing to off-chain JSON metadata.
}),
getUpdateTokenMetadataFieldInstruction({
metadata: mint.address, // Mint account that stores the metadata.
updateAuthority: client.payer, // Signer authorized to update metadata fields.
field: tokenMetadataField("Key", ["description"]), // Custom metadata field to add.
value: "Metadata stored on mint account" // Value stored for the custom metadata field.
})
]);
const initialMintAccount = await fetchMint(client.rpc, mint.address);
const initialExtensions =
unwrapOption(initialMintAccount.data.extensions) ?? [];
const initialTokenMetadata = initialExtensions.find((item) =>
isExtension("TokenMetadata", item)
);
console.dir(
{
mint: mint.address,
tokenMetadata: initialTokenMetadata
},
{ depth: null }
);
const updateMetadataTransaction = await client.sendTransaction([
getUpdateTokenMetadataFieldInstruction({
metadata: mint.address, // Mint account that stores the metadata.
updateAuthority: client.payer, // Signer authorized to update metadata fields.
field: tokenMetadataField("Name"), // Base metadata field to update.
value: "Example Token v2" // Updated value for the token name.
}),
getUpdateMetadataPointerInstruction({
mint: mint.address, // Mint account that stores the MetadataPointer extension.
metadataPointerAuthority: client.payer, // Signer authorized to update the metadata pointer.
metadataAddress: mint.address // Account address that stores the metadata.
}),
getRemoveTokenMetadataKeyInstruction({
metadata: mint.address, // Mint account that stores the metadata.
updateAuthority: client.payer, // Signer authorized to remove custom metadata.
key: "description" // Custom metadata key to remove.
}),
getUpdateTokenMetadataUpdateAuthorityInstruction({
metadata: mint.address, // Mint account that stores the metadata.
updateAuthority: client.payer, // Current signer authorized to change the update authority.
newUpdateAuthority: null // Clear the update authority so metadata can no longer be changed.
}),
getEmitTokenMetadataInstruction({
metadata: mint.address // Mint account that stores the metadata to emit.
})
]);
const updateMetadataResult = await client.rpc
.getTransaction(updateMetadataTransaction.context.signature, {
encoding: "json",
maxSupportedTransactionVersion: 1
})
.send();
const emittedDataBase64 = updateMetadataResult?.meta?.returnData?.data?.[0];
if (!emittedDataBase64) {
throw new Error("Expected token metadata return data");
}
const emittedTokenMetadata = unpackTokenMetadata(
Buffer.from(emittedDataBase64, "base64")
);
const mintAccount = await fetchMint(client.rpc, mint.address);
const extensions = unwrapOption(mintAccount.data.extensions) ?? [];
const metadataPointer = extensions.find((item) =>
isExtension("MetadataPointer", item)
);
const tokenMetadata = extensions.find((item) =>
isExtension("TokenMetadata", item)
);
console.dir(
{
mint: mint.address,
metadataPointer,
tokenMetadata,
emittedTokenMetadata
},
{ depth: null }
);
Console
Click to execute the code.

Web3.js

Instructions
import {
Connection,
Keypair,
LAMPORTS_PER_SOL,
sendAndConfirmTransaction,
SystemProgram,
Transaction
} from "@solana/web3.js";
import {
createInitializeMetadataPointerInstruction,
createInitializeMintInstruction,
createUpdateMetadataPointerInstruction,
ExtensionType,
getMetadataPointerState,
getMint,
getMintLen,
getTokenMetadata,
LENGTH_SIZE,
TOKEN_2022_PROGRAM_ID,
TYPE_SIZE
} from "@solana/spl-token";
import {
createInitializeInstruction,
createEmitInstruction,
createRemoveKeyInstruction,
unpack as unpackTokenMetadata,
createUpdateAuthorityInstruction,
createUpdateFieldInstruction,
pack,
type TokenMetadata
} from "@solana/spl-token-metadata";
const connection = new Connection("http://localhost:8899", "confirmed");
const latestBlockhash = await connection.getLatestBlockhash();
const feePayer = Keypair.generate();
const mint = Keypair.generate();
const airdropSignature = await connection.requestAirdrop(
feePayer.publicKey,
LAMPORTS_PER_SOL
);
await connection.confirmTransaction({
blockhash: latestBlockhash.blockhash,
lastValidBlockHeight: latestBlockhash.lastValidBlockHeight,
signature: airdropSignature
});
const maxMetadata: TokenMetadata = {
updateAuthority: feePayer.publicKey,
mint: mint.publicKey,
name: "Example Token v2",
symbol: "EXMPL",
uri: "https://example.com/token.json",
additionalMetadata: [["description", "Metadata stored on mint account"]]
};
const mintSpace = getMintLen([ExtensionType.MetadataPointer]);
const metadataSpace = TYPE_SIZE + LENGTH_SIZE + pack(maxMetadata).length;
const mintRent = await connection.getMinimumBalanceForRentExemption(
mintSpace + metadataSpace
);
await sendAndConfirmTransaction(
connection,
new Transaction().add(
SystemProgram.createAccount({
fromPubkey: feePayer.publicKey, // Account funding account creation.
newAccountPubkey: mint.publicKey, // New mint account to create.
lamports: mintRent, // Lamports funding the mint account rent.
space: mintSpace, // Account size in bytes for the mint plus MetadataPointer.
programId: TOKEN_2022_PROGRAM_ID // Program that owns the mint account.
}),
createInitializeMetadataPointerInstruction(
mint.publicKey, // Mint account that stores the MetadataPointer extension.
feePayer.publicKey, // Authority allowed to update the metadata pointer later.
mint.publicKey, // Account address that stores the metadata.
TOKEN_2022_PROGRAM_ID // Program that owns the mint account.
),
createInitializeMintInstruction(
mint.publicKey, // Mint account to initialize.
0, // Number of decimals for the token.
feePayer.publicKey, // Authority allowed to mint new tokens.
feePayer.publicKey, // Authority allowed to freeze token accounts.
TOKEN_2022_PROGRAM_ID // Program that owns the mint account.
),
createInitializeInstruction({
programId: TOKEN_2022_PROGRAM_ID, // Program that owns the mint and metadata.
metadata: mint.publicKey, // Mint account that stores the metadata.
updateAuthority: feePayer.publicKey, // Authority allowed to update metadata later.
mint: mint.publicKey, // Mint that the metadata describes.
mintAuthority: feePayer.publicKey, // Signer authorizing metadata initialization for the mint.
name: "Example Token", // Token name stored in metadata.
symbol: "EXMPL", // Token symbol stored in metadata.
uri: "https://example.com/token.json" // URI pointing to off-chain JSON metadata.
}),
createUpdateFieldInstruction({
programId: TOKEN_2022_PROGRAM_ID, // Program that owns the metadata.
metadata: mint.publicKey, // Mint account that stores the metadata.
updateAuthority: feePayer.publicKey, // Authority allowed to update metadata fields.
field: "description", // Custom metadata field to add.
value: "Metadata stored on mint account" // Value stored for the custom metadata field.
})
),
[feePayer, mint],
{ commitment: "confirmed" }
);
const initialTokenMetadata = await getTokenMetadata(
connection,
mint.publicKey,
"confirmed",
TOKEN_2022_PROGRAM_ID
);
console.log(
JSON.stringify(
{
mint: mint.publicKey,
tokenMetadata: initialTokenMetadata
},
null,
2
)
);
const updateMetadataSignature = await sendAndConfirmTransaction(
connection,
new Transaction().add(
createUpdateFieldInstruction({
programId: TOKEN_2022_PROGRAM_ID, // Program that owns the metadata.
metadata: mint.publicKey, // Mint account that stores the metadata.
updateAuthority: feePayer.publicKey, // Authority allowed to update metadata fields.
field: "name", // Base metadata field to update.
value: "Example Token v2" // Updated value for the token name.
}),
createUpdateMetadataPointerInstruction(
mint.publicKey, // Mint account that stores the MetadataPointer extension.
feePayer.publicKey, // Authority allowed to update the metadata pointer.
mint.publicKey, // Account address that stores the metadata.
[], // Additional signer accounts required by the instruction.
TOKEN_2022_PROGRAM_ID // Program that owns the mint account.
),
createRemoveKeyInstruction({
programId: TOKEN_2022_PROGRAM_ID, // Program that owns the metadata.
metadata: mint.publicKey, // Mint account that stores the metadata.
updateAuthority: feePayer.publicKey, // Authority allowed to remove custom metadata.
key: "description", // Custom metadata key to remove.
idempotent: false // Fail if the custom metadata key does not exist.
}),
createUpdateAuthorityInstruction({
programId: TOKEN_2022_PROGRAM_ID, // Program that owns the metadata.
metadata: mint.publicKey, // Mint account that stores the metadata.
oldAuthority: feePayer.publicKey, // Current authority allowed to change the update authority.
newAuthority: null // Clear the update authority so metadata can no longer be changed.
}),
createEmitInstruction({
programId: TOKEN_2022_PROGRAM_ID, // Program that owns the metadata.
metadata: mint.publicKey // Mint account that stores the metadata to emit.
})
),
[feePayer],
{ commitment: "confirmed" }
);
const updateMetadataTransaction = (await connection.getTransaction(
updateMetadataSignature,
{
maxSupportedTransactionVersion: 0
}
)) as any;
const emittedDataBase64 =
updateMetadataTransaction?.meta?.returnData?.data?.[0];
if (!emittedDataBase64) {
throw new Error("Expected token metadata return data");
}
const emittedTokenMetadata = unpackTokenMetadata(
Buffer.from(emittedDataBase64, "base64")
);
const mintAccount = await getMint(
connection,
mint.publicKey,
"confirmed",
TOKEN_2022_PROGRAM_ID
);
const metadataPointer = getMetadataPointerState(mintAccount);
const tokenMetadata = await getTokenMetadata(
connection,
mint.publicKey,
"confirmed",
TOKEN_2022_PROGRAM_ID
);
console.log(
JSON.stringify(
{
mint: mint.publicKey,
metadataPointer,
tokenMetadata,
emittedTokenMetadata
},
null,
2
)
);
Console
Click to execute the code.

Rust

Rust
use anyhow::{anyhow, Result};
use base64::prelude::{Engine as _, BASE64_STANDARD};
use solana_client::nonblocking::rpc_client::RpcClient;
use solana_client::rpc_config::RpcTransactionConfig;
use solana_commitment_config::CommitmentConfig;
use solana_sdk::{
pubkey::Pubkey,
signature::{Keypair, Signer},
transaction::Transaction,
};
use solana_transaction_status_client_types::UiTransactionEncoding;
use solana_system_interface::instruction::create_account;
use spl_token_2022_interface::{
extension::{
metadata_pointer::{
instruction::{
initialize as initialize_metadata_pointer,
update as update_metadata_pointer,
},
MetadataPointer,
},
BaseStateWithExtensions, ExtensionType, StateWithExtensions,
},
instruction::initialize_mint,
state::Mint,
ID as TOKEN_2022_PROGRAM_ID,
};
use spl_token_metadata_interface::{
borsh::BorshDeserialize,
instruction::{
emit as emit_token_metadata, initialize as initialize_token_metadata,
remove_key as remove_token_metadata_key,
update_authority as update_token_metadata_authority,
update_field as update_token_metadata_field,
},
state::{Field, TokenMetadata},
};
#[tokio::main]
async fn main() -> Result<()> {
let client = RpcClient::new_with_commitment(
String::from("http://localhost:8899"),
CommitmentConfig::confirmed(),
);
let fee_payer = Keypair::new();
let airdrop_signature = client
.request_airdrop(&fee_payer.pubkey(), 1_000_000_000)
.await?;
loop {
let confirmed = client.confirm_transaction(&airdrop_signature).await?;
if confirmed {
break;
}
}
let mint = Keypair::new();
let max_token_metadata = TokenMetadata {
update_authority: Some(fee_payer.pubkey()).try_into()?,
mint: mint.pubkey(),
name: "Example Token v2".to_string(),
symbol: "EXMPL".to_string(),
uri: "https://example.com/token.json".to_string(),
additional_metadata: vec![(
"description".to_string(),
"Metadata stored on mint account".to_string(),
)],
};
let mint_space =
ExtensionType::try_calculate_account_len::<Mint>(&[ExtensionType::MetadataPointer])?;
let mint_rent = client
.get_minimum_balance_for_rent_exemption(mint_space + max_token_metadata.tlv_size_of()?)
.await?;
let create_mint_transaction = Transaction::new_signed_with_payer(
&[
create_account(
&fee_payer.pubkey(), // Account funding account creation.
&mint.pubkey(), // New mint account to create.
mint_rent, // Lamports funding the mint account rent.
mint_space as u64, // Account size in bytes for the mint plus MetadataPointer.
&TOKEN_2022_PROGRAM_ID, // Program that owns the mint account.
),
initialize_metadata_pointer(
&TOKEN_2022_PROGRAM_ID, // Program that owns the mint account.
&mint.pubkey(), // Mint account that stores the MetadataPointer extension.
Some(fee_payer.pubkey()), // Authority allowed to update the metadata pointer later.
Some(mint.pubkey()), // Account address that stores the metadata.
)?,
initialize_mint(
&TOKEN_2022_PROGRAM_ID, // Program that owns the mint account.
&mint.pubkey(), // Mint account to initialize.
&fee_payer.pubkey(), // Authority allowed to mint new tokens.
Some(&fee_payer.pubkey()), // Authority allowed to freeze token accounts.
0, // Number of decimals for the token.
)?,
initialize_token_metadata(
&TOKEN_2022_PROGRAM_ID, // Program that owns the mint and metadata.
&mint.pubkey(), // Mint account that stores the metadata.
&fee_payer.pubkey(), // Authority allowed to update metadata later.
&mint.pubkey(), // Mint that the metadata describes.
&fee_payer.pubkey(), // Signer authorizing metadata initialization for the mint.
"Example Token".to_string(), // Token name stored in metadata.
"EXMPL".to_string(), // Token symbol stored in metadata.
"https://example.com/token.json".to_string(), // URI pointing to off-chain JSON metadata.
),
update_token_metadata_field(
&TOKEN_2022_PROGRAM_ID, // Program that owns the metadata.
&mint.pubkey(), // Mint account that stores the metadata.
&fee_payer.pubkey(), // Authority allowed to update metadata fields.
Field::Key("description".to_string()), // Custom metadata field to add.
"Metadata stored on mint account".to_string(), // Value stored for the custom metadata field.
),
],
Some(&fee_payer.pubkey()),
&[&fee_payer, &mint],
client.get_latest_blockhash().await?,
);
client
.send_and_confirm_transaction(&create_mint_transaction)
.await?;
let initial_mint_account = client.get_account(&mint.pubkey()).await?;
let initial_mint_state = StateWithExtensions::<Mint>::unpack(&initial_mint_account.data)?;
let initial_token_metadata = initial_mint_state.get_variable_len_extension::<TokenMetadata>()?;
println!("Mint: {}", mint.pubkey());
println!("Token Metadata: {:#?}", initial_token_metadata);
let update_metadata_transaction = Transaction::new_signed_with_payer(
&[
update_token_metadata_field(
&TOKEN_2022_PROGRAM_ID, // Program that owns the metadata.
&mint.pubkey(), // Mint account that stores the metadata.
&fee_payer.pubkey(), // Authority allowed to update metadata fields.
Field::Name, // Base metadata field to update.
"Example Token v2".to_string(), // Updated value for the token name.
),
update_metadata_pointer(
&TOKEN_2022_PROGRAM_ID, // Program that owns the mint account.
&mint.pubkey(), // Mint account that stores the MetadataPointer extension.
&fee_payer.pubkey(), // Authority allowed to update the metadata pointer.
&[], // Additional signer accounts required by the instruction.
Some(mint.pubkey()), // Account address that stores the metadata.
)?,
remove_token_metadata_key(
&TOKEN_2022_PROGRAM_ID, // Program that owns the metadata.
&mint.pubkey(), // Mint account that stores the metadata.
&fee_payer.pubkey(), // Authority allowed to remove custom metadata.
"description".to_string(), // Custom metadata key to remove.
false, // Fail if the custom metadata key does not exist.
),
update_token_metadata_authority(
&TOKEN_2022_PROGRAM_ID, // Program that owns the metadata.
&mint.pubkey(), // Mint account that stores the metadata.
&fee_payer.pubkey(), // Current authority allowed to change the update authority.
None::<Pubkey>.try_into()?, // Clear the update authority so metadata can no longer be changed.
),
emit_token_metadata(
&TOKEN_2022_PROGRAM_ID, // Program that owns the metadata.
&mint.pubkey(), // Mint account that stores the metadata to emit.
None, // Start offset for the emitted metadata slice.
None, // End offset for the emitted metadata slice.
),
],
Some(&fee_payer.pubkey()),
&[&fee_payer],
client.get_latest_blockhash().await?,
);
let update_metadata_signature = client
.send_and_confirm_transaction(&update_metadata_transaction)
.await?;
let update_metadata_result = client
.get_transaction_with_config(
&update_metadata_signature,
RpcTransactionConfig {
encoding: Some(UiTransactionEncoding::Json),
commitment: Some(CommitmentConfig::confirmed()),
max_supported_transaction_version: Some(0),
},
)
.await?;
let emitted_data = BASE64_STANDARD.decode(
update_metadata_result
.transaction
.meta
.and_then(|meta| meta.return_data.map(|return_data| return_data.data.0))
.ok_or_else(|| anyhow!("Expected token metadata return data"))?,
)?;
let emitted_token_metadata = TokenMetadata::try_from_slice(&emitted_data)?;
let mint_account = client.get_account(&mint.pubkey()).await?;
let mint_state = StateWithExtensions::<Mint>::unpack(&mint_account.data)?;
let metadata_pointer = mint_state.get_extension::<MetadataPointer>()?;
let token_metadata = mint_state.get_variable_len_extension::<TokenMetadata>()?;
println!("Mint: {}", mint.pubkey());
println!("Metadata Pointer: {:#?}", metadata_pointer);
println!("Token Metadata: {:#?}", token_metadata);
println!("Emitted Token Metadata: {:#?}", emitted_token_metadata);
Ok(())
}
Console
Click to execute the code.

Is this page helpful?

Table of Contents

Edit Page
©️ 2026 Solana 基金会版权所有