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

Velora SDK

/* eslint-disable @typescript-eslint/no-unused-vars */
import { createWalletClient, custom } from 'viem';
import { mainnet } from 'viem/chains';

// declares types for window.ethereum
import 'viem/window';
import axios from 'axios';
import {
  constructViemContractCaller,
  constructAxiosFetcher,
  constructPartialSDK,
  constructSimpleSDK,
  constructSubmitLimitOrder,
  type BuildLimitOrderInput,
} from '../';
import { assert } from 'ts-essentials';
import { txParamsToViemTxParams } from '../helpers/providers/viem';

/**
 * necessary when using write methods from SDK:
 * transactions: approve Token, Fill or Cancel Order,
 * signTypedData: signing Orders.
 */
const walletClient = createWalletClient({
  // either `viemClient` has account assigned to it at creation time,
  // or the provider `viemClient` was created with must control `account` (viemClient.getAddresses()[0]===account);
  // otherwise breaks with ` ProviderError: Unknown account 0x...`
  chain: mainnet,
  transport: custom(window.ethereum!),
});

// example of a minimal SDK for submitting Limit Orders only
async function limitOrderSDKExample() {
  const [account] = await walletClient.getAddresses();
  assert(account, 'account is necessary for Order signing');

  const contractCaller = constructViemContractCaller(
    walletClient,
    account // pass account to enable write methods (tx signing, signTypedData)
  );
  const fetcher = constructAxiosFetcher(axios);
  // SDK with `submitLimitOrder` and `submitP2POrder` methods only
  const LOrderSDK = constructPartialSDK(
    {
      contractCaller,
      fetcher,
      chainId: 1, // same chain as for walletClient
    },
    constructSubmitLimitOrder
  );

  /*
  // alternatively, SDK with all Order methods: `submitLimitOrder`,  `cancelLimitOrder`, `fillLimitOrder`, `getLimitOrders`, etc. methods
  const LOrderSDK = constructPartialSDK(
    {
      contractCaller,
      fetcher,
      chainId: 1, // same chain as for walletClient
    },
    constructAllLimitOrdersHandlers
  ); */

  const DAI = '0x6B175474E89094C44Da98b954EedeAC495271d0F';
  const HEX = '0x2b591e99afe9f32eaa6214f7b7629768c40eeb39';

  const orderInput: BuildLimitOrderInput = {
    nonce: 1,
    expiry: Math.floor(Date.now() / 1000) + 60 * 60 * 24 * 7, // week from now, in sec
    makerAsset: DAI,
    takerAsset: HEX,
    makerAmount: (1e18).toString(10),
    takerAmount: (8e18).toString(10),
    maker: account,
  };

  // submitted Order if successful
  const orderFromAPI = LOrderSDK.submitLimitOrder(orderInput);
}

async function simpleSDKExample() {
  const [account] = await walletClient.getAddresses();
  assert(account, 'account is necessary for Order signing');

  const simpleSDK = constructSimpleSDK(
    {
      axios,
      chainId: 1, // same chain as for walletClient
    },
    { viemClient: walletClient, account }
  );

  const ETH = '0xeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee';
  const DAI = '0x6B175474E89094C44Da98b954EedeAC495271d0F';
  const srcAmount = (1 * 1e18).toString();

  const destToken = '0xa0b86991c6218b36c1d19d4a2e9eb0ce3606eb48';
  const priceRoute = await simpleSDK.swap.getRate({
    srcToken: ETH,
    destToken: DAI,
    amount: srcAmount,
    userAddress: account,
    side: 'SELL',
    srcDecimals: 18,
    destDecimals: 18,
  });

  const txParams = await simpleSDK.swap.buildTx({
    srcToken: ETH,
    destToken,
    srcAmount,
    slippage: 250, // 2.5%
    priceRoute,
    userAddress: account,
  });

  // helper to cast all relevant string values to BigInt
  const vTxParams = txParamsToViemTxParams(txParams);

  const txHash = await walletClient.sendTransaction({ ...vTxParams, account });
}