ParaSwap SDK
API docs are available here :
https://developers.paraswap.network
To use ParaSwap SDK :
Install the lib using npm or yarn
yarn add paraswapThen on a Javascript file:
const { ParaSwap } = require('paraswap');
const paraSwap = new ParaSwap();ES6 or TypeScript
import { ParaSwap } from 'paraswap';
const paraSwap = new ParaSwap();To retrieve the list all available tokens:
const tokens = await paraSwap.getTokens();To get the rate of a token pair using the API:
const srcToken = '0xeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee'; // ETH
const destToken = '0x89d24a6b4ccb1b6faa2625fe562bdd9a23260359'; // DAI
const srcAmount = '1000000000000000000'; //The source amount multiplied by its decimals: 10 ** 18 here
const priceRoute: OptimalRates = await paraSwap.getRate(
srcToken,
destToken,
srcAmount,
);Where priceRoute contains the rate and the distribution among exchanges, checkout the OptimalRates type for more details.
To get the rate of a token pair using the Price Feed Contract:
This can be used for trustless integrations, the
const paraswapFeed = new ParaswapFeed(1);
const priceRoute: OptimalRates = await paraswapFeed.getRate(
srcToken,
destToken,
srcAmount,
);This is a schema that describes the data flow from price query to executing a Swap:
Also available at https://paraswap-achirecture.netlify.com
To get the allowance of an ERC20
const paraSwap = new ParaSwap().setWeb3Provider(web3Provider);
const allowance = await paraSwap.getAllowance(userAddress, tokenAddress);To approve an ERC20
const paraSwap = new ParaSwap().setWeb3Provider(web3Provider);
const txHash = await paraSwap.approveToken(amount, userAddress, tokenAddress);To build and sign a transaction
const srcToken = '0xeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee';
const destToken = '0x89d24a6b4ccb1b6faa2625fe562bdd9a23260359';
const srcAmount = '1000000000000000000'; //The source amount multiplied by its decimals
const senderAddress = '0xfceA770875E7e6f25E33CEa5188d12Ef234606b4';
const receiver = '0x8B4e846c90a2521F0D2733EaCb56760209EAd51A'; // Useful in case of swap and transfer
const referrer = 'my-company-or-nick-name';
const txParams = await paraSwap.buildTx(
srcToken,
destToken,
srcAmount,
destAmount,
priceRoute,
senderAddress,
referrer,
receiver,
);
web3.eth.sendTransaction(
txParams,
async (err: Error, transactionHash: string) => {
if (err) {
return this.setState({ error: err.toString(), loading: false });
}
console.log('transactionHash', transactionHash);
},
);To run the example locally:
Created an .env file with these 2 env variables:
PROVIDER_URL=YOUR_PROVIDRER_URL_OR_INFURA_URL
NODE_ENV=productionrun
yarn install paraswapFor local developement you can run
yarn devFor production build:
yarn buildWhich will generate a production build on "dist" folder