Relayer Gasless Contract for SimpleStorage Contract with Truffle Test

Understanding the GaslessRelayer Contract

The GaslessRelayer contract enables gasless transactions by relaying transactions on behalf of users. Here’s a brief overview of the key components:

• addToWhitelist(address _addressForWl): This function allows the contract owner to add an address to the whitelist, granting it permission to use the relayer.
• setGasPrice(uint256 newGasPrice): Allows the contract owner to set a new gas price threshold that users must meet to use the relayer.
• getNonce(address user): Returns the nonce for a given user’s address.
• relay(...): The main function for relaying transactions. It verifies the signature, checks the nonce, and relays the transaction to the target contract.
• getMsgHash(...): Calculates the message hash for a given target, data, and nonce.
• getDataHash(...): Calculates the data hash for a given data input.
• recoverSigner(...): Recovers the signer’s address from a given message hash and signature.
• relayWithGasPrice(...): A helper function that relays a transaction while ensuring the gas price is above the specified threshold.

Installing dependencies:-

yarn

Running commands:-

//Start Ganache_cli for blockchain instance
yarn global add ganache-cli

//start ganache-cli
npx ganache-cli

// To compile the smart contract
yarn compile

// To deploy the smart contrct on polygon blockchain
yarn deploy

// To test the smart contract file
yarn test

Testing the GaslessRelayer Contract

• The provided test script (test/GaslessRelayer.js) demonstrates how to interact with the GaslessRelayer contract and perform various operations, including:
• Deploying the GaslessRelayer and SimpleStorage contracts.
• Adding a signer address to the whitelist.
• Calculating data and message hashes.
• Signing a message.
• Relaying a transaction using the GaslessRelayer.

// Test the GaslessRelayer with command:
yarn test .\test\GaslessRelayer.test.js

• Gasless transactions require a relayer to pay for the gas. Make sure you have a reliable and trusted relayer before using this contract on a mainnet or production environment. Always test your contracts thoroughly on a local network or testnet before deploying to the mainnet. Security is crucial in smart contract development. Audit your contracts for potential vulnerabilities and follow best practices.