제로 가스 트랜잭션

1단계. 지갑 연결, 잔액이 0.01 USDT0으로 표시됩니다.

2단계. 가스 면제를 통해 트랜잭션 전송 → [실행]

3단계. 결과
        tx:                   0x8f3a...2d41
        귀하가 지불한 가스 수수료:  0.000000 USDT0
        이후 잔액:            0.01 USDT0

// config.ts
import { ethers } from "ethers";
import "dotenv/config";
 
export const CONFIG = {
  RPC_URL: "https://rpc.testnet.stable.xyz",
  CHAIN_ID: 2201, // 988 for mainnet
  WAIVER_SERVER: "https://waiver.testnet.stable.xyz",
  USDT0_ADDRESS: "0x78Cf24370174180738C5B8E352B6D14c83a6c9A9",
};
 
export const provider = new ethers.JsonRpcProvider(CONFIG.RPC_URL);
export const userWallet = new ethers.Wallet(process.env.USER_PRIVATE_KEY!, provider);

// signInner.ts
import { ethers } from "ethers";
import { CONFIG, provider, userWallet } from "./config";
 
const usdt0 = new ethers.Contract(CONFIG.USDT0_ADDRESS, [
  "function transfer(address to, uint256 amount) returns (bool)"
], provider);
 
const callData = usdt0.interface.encodeFunctionData("transfer", [
  "0xRecipientAddress",
  ethers.parseUnits("0.001", 18),
]);
 
const gasLimit = await provider.estimateGas({
  from: userWallet.address,
  to: CONFIG.USDT0_ADDRESS,
  data: callData,
});
 
const nonce = await provider.getTransactionCount(userWallet.address);
 
const innerTx = {
  to: CONFIG.USDT0_ADDRESS,
  data: callData,
  value: 0,
  gasPrice: 0,
  gasLimit,
  nonce,
  chainId: CONFIG.CHAIN_ID,
};
 
export const signedInnerTx = await userWallet.signTransaction(innerTx);
console.log("Signed InnerTx:", signedInnerTx);

npx tsx signInner.ts

Signed InnerTx: 0xf8a8...c1

// submit.ts
import { CONFIG } from "./config";
import { signedInnerTx } from "./signInner";
 
const response = await fetch(`${CONFIG.WAIVER_SERVER}/v1/submit`, {
  method: "POST",
  headers: {
    "Content-Type": "application/json",
    Authorization: `Bearer ${process.env.WAIVER_API_KEY}`,
  },
  body: JSON.stringify({ transactions: [signedInnerTx] }),
});
 
const reader = response.body!.getReader();
const decoder = new TextDecoder();
let txHash = "";
 
while (true) {
  const { done, value } = await reader.read();
  if (done) break;
  for (const line of decoder.decode(value).trim().split("\n")) {
    const result = JSON.parse(line);
    if (result.success) {
      txHash = result.txHash;
      console.log(`tx confirmed: ${txHash}`);
    } else {
      console.error(`tx failed: ${result.error.message}`);
    }
  }
}
export { txHash };

npx tsx submit.ts

tx confirmed: 0x8f3a...2d41

// verify.ts
import { provider } from "./config";
import { txHash } from "./submit";
 
const receipt = await provider.getTransactionReceipt(txHash);
 
const gasUsed = receipt!.gasUsed;
const effectiveGasPrice = receipt!.gasPrice;
const totalFee = gasUsed * effectiveGasPrice;
 
console.log("Gas used:           ", gasUsed.toString());
console.log("Effective gas price:", effectiveGasPrice.toString());
console.log("Gas fee paid:       ", `${totalFee.toString()} USDT0 (wei-equivalent)`);

npx tsx verify.ts

Gas used:            21000
Effective gas price: 0
Gas fee paid:        0 USDT0 (wei-equivalent)