This guide provides instructions for transferring assets between wallets and contracts using the SDK. It includes methods to validate balances and initiate and configure transfer requests.
The transfer
method initiates a transaction request that transfers an asset from one wallet to another. This method requires three parameters:
Upon execution, this function returns a promise that resolves to a transaction response. To wait for the transaction to be processed, call response.waitForResult()
.
Here is an example of how to use the transfer
function:
import { Provider, Wallet } from 'fuels';
import { LOCAL_NETWORK_URL, WALLET_PVT_KEY, WALLET_PVT_KEY_2 } from '../../env';
const provider = await Provider.create(LOCAL_NETWORK_URL);
const sender = Wallet.fromPrivateKey(WALLET_PVT_KEY, provider);
const destination = Wallet.fromPrivateKey(WALLET_PVT_KEY_2, provider);
const amountToTransfer = 500;
const baseAssetId = sender.provider.getBaseAssetId();
const response = await sender.transfer(
destination.address,
amountToTransfer,
baseAssetId
);
await response.waitForResult();
// Retrieve balances
const balance = await destination.getBalance(baseAssetId);
In the previous example, we used the transfer
method which creates a ScriptTransactionRequest
, populates its data with the provided transfer information and submits the transaction.
However, there may be times when you need the Transaction ID before actually submitting it to the node. To achieve this, you can simply call the createTransfer
method instead.
This method also creates a ScriptTransactionRequest
and populates it with the provided data but returns the request object prior to submission.
import { Provider, Wallet } from 'fuels';
import { LOCAL_NETWORK_URL, WALLET_PVT_KEY, WALLET_PVT_KEY_2 } from '../../env';
const provider = await Provider.create(LOCAL_NETWORK_URL);
const sender = Wallet.fromPrivateKey(WALLET_PVT_KEY, provider);
const destination = Wallet.fromPrivateKey(WALLET_PVT_KEY_2, provider);
const amountToTransfer = 200;
const assetId = provider.getBaseAssetId();
const transactionRequest = await sender.createTransfer(
destination.address,
amountToTransfer,
assetId
);
const chainId = provider.getChainId();
const transactionId = transactionRequest.getTransactionId(chainId);
const response = await sender.sendTransaction(transactionRequest);
// The transaction id is the same one returned by the code above.
const { id } = await response.wait();
Note: Any changes made to a transaction request will alter the transaction ID. Therefore, you should only get the transaction ID after all modifications have been made.
import { bn, Provider, Wallet } from 'fuels';
import { LOCAL_NETWORK_URL, WALLET_PVT_KEY, WALLET_PVT_KEY_2 } from '../../env';
const provider = await Provider.create(LOCAL_NETWORK_URL);
const sender = Wallet.fromPrivateKey(WALLET_PVT_KEY, provider);
const destination = Wallet.fromPrivateKey(WALLET_PVT_KEY_2, provider);
const amountToTransfer = 200;
const assetId = provider.getBaseAssetId();
const transactionRequest = await sender.createTransfer(
destination.address,
amountToTransfer,
assetId
);
const chainId = provider.getChainId();
const transactionId = transactionRequest.getTransactionId(chainId);
/**
* Modifying any property of the transaction request, except for the number
* of witnesses within the ".witnesses" array, will generate a new transaction
* hash, resulting in a different transaction ID.
*/
transactionRequest.gasLimit = bn(1000);
const response = await sender.sendTransaction(transactionRequest);
// The transaction id here is NOT the same one returned above.
const { id } = await response.wait();
To transfer assets to multiple wallets, use the Account.batchTransfer
method:
import type { TransferParams } from 'fuels';
import { Provider, Wallet } from 'fuels';
import { LOCAL_NETWORK_URL, WALLET_PVT_KEY } from '../../env';
const provider = await Provider.create(LOCAL_NETWORK_URL);
const sender = Wallet.fromPrivateKey(WALLET_PVT_KEY, provider);
const recipient1 = Wallet.generate({ provider });
const recipient2 = Wallet.generate({ provider });
const someOtherAssetId =
'0x0101010101010101010101010101010101010101010101010101010101010101';
const transfersToMake: TransferParams[] = [
{
amount: 100,
destination: recipient1.address,
assetId: provider.getBaseAssetId(),
},
{
amount: 200,
destination: recipient2.address,
assetId: provider.getBaseAssetId(),
},
{
amount: 300,
destination: recipient2.address,
assetId: someOtherAssetId,
},
];
const tx = await sender.batchTransfer(transfersToMake);
await tx.waitForResult();
When transferring assets to a deployed contract, we use the transferToContract
method, which shares a similar parameter structure with the transfer
method.
However, instead of supplying the target wallet's address, as done in destination.address
for the transfer method, we need to provide an instance of Address created from the deployed contract id.
If you have the Contract instance of the deployed contract, you can simply use its id
property. However, if the contract was deployed with forc deploy
or not by you, you will likely only have its ID in a hex string format. In such cases, you can create an Address instance from the contract ID using Address.fromAddressOrString('0x123...')
.
Here's an example demonstrating how to use transferToContract
:
import { Provider, Wallet } from 'fuels';
import { LOCAL_NETWORK_URL, WALLET_PVT_KEY } from '../../env';
import { CounterFactory } from '../../typegend';
const provider = await Provider.create(LOCAL_NETWORK_URL);
const sender = Wallet.fromPrivateKey(WALLET_PVT_KEY, provider);
const deploy = await CounterFactory.deploy(sender);
const { contract } = await deploy.waitForResult();
const amountToTransfer = 400;
const assetId = provider.getBaseAssetId();
const contractId = contract.id;
const tx = await sender.transferToContract(
contractId,
amountToTransfer,
assetId
);
await tx.waitForResult();
Note: Use transferToContract
exclusively for transfers to a contract. For transfers to an account address, use transfer
instead.
Similar to the Account.batchTransfer
method, you can transfer multiple assets to multiple contracts using the Account.batchTransferToContracts
method. Here's how it works:
import type { ContractTransferParams } from 'fuels';
import { Provider, Wallet } from 'fuels';
import { TestAssetId } from 'fuels/test-utils';
import { LOCAL_NETWORK_URL, WALLET_PVT_KEY } from '../../env';
import { CounterFactory, EchoValuesFactory } from '../../typegend';
const provider = await Provider.create(LOCAL_NETWORK_URL);
const sender = Wallet.fromPrivateKey(WALLET_PVT_KEY, provider);
const baseAssetId = provider.getBaseAssetId();
const assetA = TestAssetId.A.value;
const deploy1 = await CounterFactory.deploy(sender);
const deploy2 = await EchoValuesFactory.deploy(sender);
const { contract: contract1 } = await deploy1.waitForResult();
const { contract: contract2 } = await deploy2.waitForResult();
const contractTransferParams: ContractTransferParams[] = [
{
contractId: contract1.id,
amount: 999,
assetId: baseAssetId,
},
{
contractId: contract1.id,
amount: 550,
assetId: assetA,
},
{
contractId: contract2.id,
amount: 200,
assetId: assetA,
},
];
const transfer = await sender.batchTransferToContracts(contractTransferParams);
await transfer.waitForResult();
Always remember to call the waitForResult()
function on the transaction response. That ensures the transaction has been mined successfully before proceeding.
Note: Use batchTransferToContracts
solely for transferring assets to contracts. Do not use account addresses with this method. For multiple account transfers, use batchTransfer
instead.
Before you transfer assets, please make sure your wallet has enough funds. Attempting a transfer without enough funds will result in the error: The transaction does not have enough funds to cover its execution.
You can see how to check your balance at the checking-balances
page.