@velora-dex/sdk/src/examples/quote.ts

Velora SDK

/* eslint-disable @typescript-eslint/no-unused-vars */
import axios from 'axios';
import { ethers, Wallet } from 'ethersV5';
import {
  constructPartialSDK,
  constructEthersContractCaller,
  constructAxiosFetcher,
  constructAllDeltaOrdersHandlers,
  constructGetQuote,
  constructSwapSDK,
  OptimalRate,
  DeltaPrice,
} from '..';
import { startStatusCheck } from './helpers/delta';

const fetcher = constructAxiosFetcher(axios);

const provider = ethers.getDefaultProvider(1);
const signer = Wallet.createRandom().connect(provider);
const account = signer.address;
const contractCaller = constructEthersContractCaller({
  ethersProviderOrSigner: provider,
  EthersContract: ethers.Contract,
});

// type AdaptersFunctions & ApproveTokenFunctions<ethers.ContractTransaction>
const quoteSDK = constructPartialSDK(
  {
    chainId: 1,
    fetcher,
    contractCaller,
  },
  constructAllDeltaOrdersHandlers,
  constructSwapSDK,
  constructGetQuote
);

const DAI_TOKEN = '0x6b175474e89094c44da98b954eedeac495271d0f';
const USDC_TOKEN = '0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48';

/**
 * mode='all' returns Delta pricing when possible, with Market price as a fallback.
 * (mode='delta' and mode='market' request a single pricing source.)
 */
async function quoteExample() {
  const amount = '1000000000000'; // wei

  const quote = await quoteSDK.getQuote({
    srcToken: DAI_TOKEN,
    destToken: USDC_TOKEN,
    amount,
    userAddress: account,
    srcDecimals: 18,
    destDecimals: 6,
    mode: 'all',
    side: 'SELL',
    // partner: "..." // if available
  });

  if ('delta' in quote) {
    // Delta path — quote.delta is the v2 DeltaPrice (route-based)
    await handleDeltaQuote({ amount, deltaPrice: quote.delta });
  } else {
    console.log(
      `Delta Quote failed: ${quote.fallbackReason.errorType} - ${quote.fallbackReason.details}`
    );
    // settle against the current market price instead
    await handleMarketQuote({ amount, priceRoute: quote.market });
  }
}

async function handleDeltaQuote({
  amount,
  deltaPrice,
}: {
  amount: string;
  deltaPrice: DeltaPrice;
}) {
  /**
   * refer to examples/delta for more details
   */
  const DeltaContract = await quoteSDK.getDeltaContract();

  // or sign a Permit1 or Permit2 TransferFrom for DeltaContract
  await quoteSDK.approveTokenForDelta(amount, DAI_TOKEN);

  // v2 order building is server-side: pass the quoted route/side, no deltaPrice
  const deltaAuction = await quoteSDK.submitDeltaOrder({
    route: deltaPrice.route, // or pick from deltaPrice.alternatives
    side: deltaPrice.side,
    owner: account,
    // beneficiary: anotherAccount, // if need to send destToken to another account
    // permit: "0x1234...", // if signed a Permit1 or Permit2 TransferFrom for DeltaContract
    slippage: 50, // 50 bps = 0.5% slippage
  });

  // poll if necessary
  startStatusCheck(() => quoteSDK.getDeltaOrderById(deltaAuction.id));

  return deltaAuction;
}

async function handleMarketQuote({
  amount,
  priceRoute,
}: {
  amount: string;
  priceRoute: OptimalRate;
}) {
  const TokenTransferProxy = await quoteSDK.getSpender();

  // or sign a Permit1 or Permit2 TransferFrom for TokenTransferProxy
  const approveTxHash = quoteSDK.approveToken(amount, DAI_TOKEN);

  const txParams = await quoteSDK.buildTx({
    srcToken: DAI_TOKEN,
    destToken: USDC_TOKEN,
    srcAmount: amount,
    slippage: 250, // 2.5%
    priceRoute,
    userAddress: account,
    // partner: '...' // if available
  });

  const swapTx = await signer.sendTransaction(txParams);
  return swapTx;
}