flint-gasless-sdk v1.1.0

Flint Gasless SDK

Flint gasless SDK (Gaspay) does the magic of enabling gasless feature in any dApp with just a few lines of code. Users can pay in ERC20 tokens to send transactions to the blockchain that needs native tokens otherwise.

Installation

Recommended Node version 16 or higher

  npm install flint-gasless-sdk

Documentation

import { GaspayManager } from "flint-gasless-sdk";

const gaspayManager = new GaspayManager("<FLINT_GASPAY_API_KEY>");

const { dataToSign, functionSignature } =
      await gaspayManager.generateApprovalSignature(
        <WALLET_ADDRESS>,
        <ERC20_TOKEN_ADDRESS>,
        <CHAIN_ID>
);

Get the signature from the user

You can use default ethereum injected by the wallet provider or wagmi to initiate a signature from the user in your dApp.

Note: This will open metamask or any other ethereum wallet

const signature = await ethereum.request({
            method: 'eth_signTypedData_v4',
            params: [walletAddress, JSON.stringify(dataToSign)],
    });

Or

You can read about signing typed data here: wagmi

import { useSignTypedData } from 'wagmi'

const signTypedData = useSignTypedData({
    domain,
    types,
    value,
    onSuccess(data) {
      console.log('Success', data)
      // Call gasless sdk on this data signature returned
    },
  })

Finally send this transaction through the SDK

const txDetails = await gaspayManager.sendApprovalTransaction(
        data,
        functionSig,
        <ERC20_TOKEN_ADDRESS>,
        <WALLET_ADDRESS>,
        <CHAIN_ID>
    );

Get signature for SWAP

const swapSig = await gaspayManager.generateSwapSignature(
    merchantApiKey,
    params,
    chainId,
    walletAddress
)

Send the SWAP signature

const result = await gaspayManager.sendSwapTransaction(
    merchantApiKey,
    signature,
    params,
    chainId,
    walletAddress
)

And voilà!! You have gasless feature enabled in your dApp with just a few lines of code 🥳

API Reference

Generate approval signature

generateApprovalSignature(walletAddress: string, fromToken: string, chainId: string): Promise<ApprovalSignature>;

Send approval transaction

  sendApprovalTransaction(signature: string, functionSignature: string, fromToken: string, walletAddress: string, chainId: string): Promise<any>;

Get swap signature

  generateSwapSignature (merchantApiKey: string, params: any, chainId: string, walletAddress: string): Promise<string>

Send swap transaction

  sendSwapTransaction (merchantApiKey: string, signature: string, params: any, chainId: string, walletAddress: string): Promise<any>

Authors

• abhishek

License

MIT