Cookbook

import { TonApiClient } from '@ton-api/client';
import { storeMessageRelaxed, WalletContractV5R1 } from '@ton/ton';
import { Address, beginCell, internal, toNano, SendMode, external, storeMessage } from '@ton/core';
import { mnemonicToPrivateKey } from '@ton/crypto';
import { ContractAdapter } from '@ton-api/ton-adapter';
 
// if you need to send lots of requests in parallel,
// make sure you use a tonapi token.
const ta = new TonApiClient({
    baseUrl: 'https://tonapi.io',
    // apiKey: 'YOUR API KEY'
});
 
const provider = new ContractAdapter(ta);
 
const OP_CODES = {
    TK_RELAYER_FEE: 0x878da6e3,
    JETTON_TRANSFER: 0xf8a7ea5
};
 
// Amount for jetton transfer. Usually 0.05 TON is enough for most jetton transfers without forwardBody
const BASE_JETTON_SEND_AMOUNT = toNano(0.05);
 
const main = async () => {
    
    // this is a simple example of how to send a gasless transfer.
	// you only need to specify your seed and a destination address.
 
	// the seed is not sent to the network, it is used to sign messages locally.
 
    const seed =
        '..!!! REPLACE THIS WITH YOUR SEED !!! ..'; // wallet seed `word1 word2 word3 ... word24`
    const destination = Address.parse('..!!! REPLACE THIS WITH A CORRECT DESTINATION !!!..'); // replace with a correct recipient address
    const usdtMaster = Address.parse('EQCxE6mUtQJKFnGfaROTKOt1lZbDiiX1kCixRv7Nw2Id_sDs'); // USDt jetton master.
 
    const jettonAmount = 1_000_000n; // amount in the smallest jetton units. This is 1 USDt.
 
    const keyPair = await mnemonicToPrivateKey(seed.split(' '));
    const workchain = 0;
    const wallet = WalletContractV5R1.create({ workchain, publicKey: keyPair.publicKey });
    const contract = provider.open(wallet);
 
    console.log('Wallet address:', wallet.address.toString());
 
    const jettonWalletAddressResult = await ta.blockchain.execGetMethodForBlockchainAccount(
        usdtMaster,
        'get_wallet_address',
        {
            args: [wallet.address.toRawString()]
        }
    );
    const jettonWallet = Address.parse(jettonWalletAddressResult.decoded.jettonWalletAddress);
 
    // we use USDt in this example,
	// so we just print all supported gas jettons and get the relay address.
	// we have to send excess to the relay address in order to make a transfer cheaper.
    const relayerAddress = await printConfigAndReturnRelayAddress();
 
    // Create payload for jetton transfer
    const tetherTransferPayload = beginCell()
        .storeUint(OP_CODES.JETTON_TRANSFER, 32)
        .storeUint(0, 64)
        .storeCoins(jettonAmount) // 1 USDT
        .storeAddress(destination) // address for receiver
        .storeAddress(relayerAddress) // address for excesses
        .storeBit(false) // null custom_payload
        .storeCoins(1n) // count of forward transfers in nanoton
        .storeMaybeRef(undefined)
        .endCell();
 
    const messageToEstimate = beginCell()
        .storeWritable(
            storeMessageRelaxed(
                internal({
                    to: jettonWallet,
                    bounce: true,
                    value: BASE_JETTON_SEND_AMOUNT,
                    body: tetherTransferPayload
                })
            )
        )
        .endCell();
 
    // we send a single message containing a transfer from our wallet to a desired destination.
	// as a result of estimation, TonAPI returns a list of messages that we need to sign.
	// the first message is a fee transfer to the relay address, the second message is our original transfer.
    const params = await ta.gasless.gaslessEstimate(usdtMaster, {
        walletAddress: wallet.address,
        walletPublicKey: keyPair.publicKey.toString('hex'),
        messages: [
            {
                boc: messageToEstimate
            }
        ]
    }); // .catch(res => res.json().then(console.error));
 
    console.log('Estimated transfer:', params);
 
    const seqno = await contract.getSeqno();
 
    // params is the same structure as params in tonconnect
    const tetherTransferForSend = wallet.createTransfer({
        seqno,
        authType: 'internal',
        timeout: Math.ceil(Date.now() / 1000) + 5 * 60,
        secretKey: keyPair.secretKey,
        sendMode: SendMode.PAY_GAS_SEPARATELY + SendMode.IGNORE_ERRORS,
        messages: params.messages.map(message =>
            internal({
                to: message.address,
                value: BigInt(message.amount),
                body: message.payload
            })
        )
    });
 
    const extMessage = beginCell()
        .storeWritable(
            storeMessage(
                external({
                    to: contract.address,
                    init: seqno === 0 ? contract.init : undefined,
                    body: tetherTransferForSend
                })
            )
        )
        .endCell();
 
    // Send a gasless transfer
    ta.gasless
        .gaslessSend({
            walletPublicKey: keyPair.publicKey.toString('hex'),
            boc: extMessage
        })
        .then(() => console.log('A gasless transfer sent!'))
        .catch(res => res.json().then(console.error));
};
 
async function printConfigAndReturnRelayAddress(): Promise<Address> {
    const cfg = await ta.gasless.gaslessConfig();
 
    console.log('Available jettons for gasless transfer');
    console.log(cfg.gasJettons.map(gasJetton => gasJetton.masterId));
 
    console.log(`Relay address to send fees to: ${cfg.relayAddress}`);
    return cfg.relayAddress;
}
 
main().catch(console.error);