模拟交易

交易模拟功能允许您在不支付手续费的情况下，预览提交交易的成本和效果。您可以用它来预估手续费、测试交易或检查可能的输出结果。

要模拟交易，您需要传入一个交易对象以及签名账户信息：

simulate-a-transaction.ts

import {
    Account,
    Aptos,
    AptosConfig,
    Network,
} from "@aptos-labs/ts-sdk";
 
async function example() {
    let sender = Account.generate();
    let receiver = Account.generate();
 
    // 0. 初始化客户端和测试账户
    const config = new AptosConfig({ network: Network.DEVNET });
    const aptos = new Aptos(config);
 
    await aptos.fundAccount({
        accountAddress: sender.accountAddress,
        amount: 100_000_000,
    });
 
    // 1. 构建交易以预览其影响
    const transaction = await aptos.transaction.build.simple({
        sender: sender.accountAddress,
        data: {
        // Aptos 上的所有交易都通过智能合约实现
        function: "0x1::aptos_account::transfer",
        functionArguments: [receiver.accountAddress, 100],
        },
    });
 
    // 2. 模拟执行该交易可能产生的结果
    const [userTransactionResponse] = await aptos.transaction.simulate.simple({
        signerPublicKey: sender.publicKey,
        transaction,
    });
    console.log(userTransactionResponse)
 
    // 如果手续费合适，继续签名流程！
    // ...
}
 
example();

这将产生与实际提交交易相同的输出结果。

在 aptos.transaction.simulate.simple 方法中，signerPublicKey 参数用于在交易模拟期间验证签名者的认证密钥。该参数是可选的，如果省略，模拟将跳过认证密钥检查。例如：

// 2. 模拟执行该交易可能产生的结果（跳过认证密钥检查）
const [userTransactionResponse] = await aptos.transaction.simulate.simple({
    transaction,
});

示例输出

Terminal

{
  version: '9534925',
  hash: '0xea50b6fbea39ad1ba015d11cda0e7478334669c34830bc3df067a260d680893c',
  state_change_hash: '0x0000000000000000000000000000000000000000000000000000000000000000',
  event_root_hash: '0x0000000000000000000000000000000000000000000000000000000000000000',
  state_checkpoint_hash: null,
  gas_used: '9',
  success: true,
  vm_status: 'Executed successfully',
  accumulator_root_hash: '0x0000000000000000000000000000000000000000000000000000000000000000',
  changes: [
    {
      address: '0x811d5a94ccb597fa2a4f7872a3c678867cff94130d9378c39304c1354ef54abe',
      state_key_hash: '0x09adecee8779b64d05847488e2dbec6679c0c9e2fe618caf0793472ba3a7e4ab',
      data: [Object],
      type: 'write_resource'
    },
    {
      address: '0x811d5a94ccb597fa2a4f7872a3c678867cff94130d9378c39304c1354ef54abe',
      state_key_hash: '0x0c70ede5412277b81d9f8d99369930ed5d56ad65862e3e878ad22dd5500833d0',
      data: [Object],
      type: 'write_resource'
    },
    {
      address: '0xf40c314051890d16ba0a2ba427e003a83e730956fdeccf6c8eebc893a229ddc1',
      state_key_hash: '0x503f9cffb248036da24e18875f3dce72bb33d1d3ef5cfdbdb2fb3411cd718f4f',
      data: [Object],
      type: 'write_resource'
    },
    {
      state_key_hash: '0x6e4b28d40f98a106a65163530924c0dcb40c1349d3aa915d108b4d6cfc1ddb19',
      handle: '0x1b854694ae746cdbd8d44186ca4929b2b337df21d1c74633be19b2710552fdca',
      key: '0x0619dc29a0aac8fa146714058e8dd6d2d0f3bdf5f6331907bf91f3acd81e6935',
      value: '0x708f579f62cb01000100000000000000',
      data: null,
      type: 'write_table_item'
    }
  ],
  sender: '0x811d5a94ccb597fa2a4f7872a3c678867cff94130d9378c39304c1354ef54abe',
  sequence_number: '0',
  max_gas_amount: '200000',
  gas_unit_price: '100',
  expiration_timestamp_secs: '1718983701',
  payload: {
    function: '0x1::aptos_account::transfer',
    type_arguments: [],
    arguments: [
      '0xf40c314051890d16ba0a2ba427e003a83e730956fdeccf6c8eebc893a229ddc1',
      '100'
    ],
    type: 'entry_function_payload'
  },
  signature: {
    public_key: '0x966b6b9aa8feb58ee1b911235dea1f185b9169de56303d18bb59937066881e44',
    signature: '0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000',
    type: 'ed25519_signature'
  },
  events: [
    {
      guid: [Object],
      sequence_number: '0',
      type: '0x1::coin::CoinWithdraw',
      data: [Object]
    },
    {
      guid: [Object],
      sequence_number: '0',
      type: '0x1::coin::WithdrawEvent',
      data: [Object]
    },
    {
      guid: [Object],
      sequence_number: '0',
      type: '0x1::coin::CoinDeposit',
      data: [Object]
    },
    {
      guid: [Object],
      sequence_number: '1',
      type: '0x1::coin::DepositEvent',
      data: [Object]
    },
    {
      guid: [Object],
      sequence_number: '0',
      type: '0x1::transaction_fee::FeeStatement',
      data: [Object]
    }
  ],
  timestamp: '1718983681460047'
}

查看这里了解如何构建、模拟和提交交易的完整示例。

模拟更复杂的交易

您还可以通过以下指南学习如何模拟更高级的交易：

赞助交易
多代理交易
多重签名V2交易：详情请见下一节

模拟链上多重签名（v2）交易

对于多重签名交易，有两种模拟类型：

在目标有效负载上链前进行模拟，忽略投票状态
在执行前对已批准的链上多重签名交易进行模拟，以验证输出和估算gas费用

执行第一种类型时，您可以将目标有效负载作为赞助交易进行模拟，将多重签名账户设为发送方，并将费用支付方设为0x0以绕过模拟期间的gas费用支付。例如：

// 生成一个原始交易，使用多重签名地址作为发送方，
// 提供的入口函数有效负载，以及0x0作为费用支付方地址
const transactionToSimulate = await aptos.transaction.build.simple({
  sender: multisigAddress,
  data: {
    function: "0x1::aptos_account::transfer",
    functionArguments: [recipient.accountAddress, 1_000_000],
  },
  withFeePayer: true,
});
 
// 模拟交易，跳过对发送方和费用支付方的公钥/授权密钥检查
const [simulateMultisigTx] = await aptos.transaction.simulate.simple({
  transaction: transactionToSimulate,
});

此设置允许您在上链前预览目标有效负载的结果。此处省略了signerPublicKey以跳过发送方的认证密钥检查，因为多重签名账户没有公钥。此外，feePayerAddress默认为0x0，且省略feePayerPublicKey以绕过模拟期间的gas费用支付。当这个有效负载在提交和批准后被执行时，执行交易的所有者将支付gas费用。

对于第二种模拟类型，即对已批准的链上多重签名有效负载交易进行最终验证和gas估算时，请使用以下方法：

const transactionPayload: TransactionPayloadMultiSig = await generateTransactionPayload({
  multisigAddress,
  function: "0x1::aptos_account::transfer",
  functionArguments: [recipient.accountAddress, 1_000_000],
  aptosConfig: config,
});
 
const rawTransaction = await generateRawTransaction({
  aptosConfig: config,
  sender: owner.accountAddress,
  payload: transactionPayload,
});
 
const [simulateMultisigTx] = await aptos.transaction.simulate.simple({
  signerPublicKey: owner.publicKey,
  transaction: new SimpleTransaction(rawTransaction),
});

请注意signerPublicKey是可选的，如果您希望在模拟期间跳过发送方的认证密钥检查，可以省略该参数。

完整源代码…要查看完整代码，请参考 Multisig V2 示例。

Transactions Multi-Agent Transactions