2⃣

sponsoredCall

SDK Method 3️⃣

After reading this page: 
You'll know how to use theSponsoredCallSDK method. This uses the 1Balance payment method, allowing you to sponsor some/all of your user's gas costs.
You'll see some code which will help you send a relay request within minutes.
Overview
sponsoredCall utilises authentication via a sponsor API key to sponsor gasless transactions  for your users securely. The payment method is Gelato 1Balance.
SDK method: sponsoredCall
const sponsoredCall = async (
  request: SponsoredCallRequest,
  sponsorApiKey: string,
  options?: RelayRequestOptions
): Promise<RelayResponse>
Arguments:
request: this is the request body used to send a request.
sponsorApiKey : an API key used to authenticate your sponsorship. 
options?: RelayRequestOptions is an optional request object
Return Object: RelayResponse
type RelayResponse = {
  taskId: string;
};
taskId: your unique relay task ID which can be used for tracking your request.
Optional Parameters 
See Optional Parameters. 
Sending a Request
Request Body
const request = {
  chainId: BigNumberish;
  target: string;
  data: BytesLike;
};
chainId: the chain ID of the chain where the target smart contract is deployed.
target: the address of the target smart contract.
data: encoded payload data (usually a function selector plus the required arguments) used to call the required target address.
Example Code
Please see relay-docs-examples for more in-depth code explainers.
Since sponsoredCall assumes you have your own security logic, i.e. replay and re-entrancy protection, built in, you can go ahead and generate the payload for your function call and populate a request object.
1. Import GelatoRelaySDK into your front-end .js project
1
import { GelatoRelay, SponsoredCallRequest } from "@gelatonetwork/relay-sdk";
2
const relay = new GelatoRelay();
2. Generate a payload for your target contract
This is an example using Gelato's CounterERC2771.sol which is deployed on Goerli and Polygon.
// set up target address and function signature abi
const counter = "0xEEeBe2F778AA186e88dCf2FEb8f8231565769C27"; 
const abi = ["function increment()"];
​
// generate payload using front-end provider such as MetaMask
const provider = new ethers.providers.Web3Provider(window.ethereum);
const signer = provider.getSigner();
​
const contract = new ethers.Contract(counterAddress, abi, signer);
const { data } = await contract.populateTransaction.increment();
3. Send the payload to Gelato
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// Populate a relay request
2
const request: SponsoredCallRequest = {
3
  chainId: provider.network.chainId,
4
  target: counter,
5
  data: data,
6
};
7
​
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// Without a specific API key, the relay request will fail! 
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// Go to https://relay.gelato.network to get a testnet API key with 1Balance.
10
// Send the relay request using Gelato Relay!
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const relayResponse = await relay.sponsoredCall(request, apiKey);

Gelato's Fee Oracle

sponsoredCallERC2771

Last modified 1mo ago