How to use ether.js with OpenZeppelin MinimalForwarder

[sy2737]

MinimalForwarder is used to relay transactions, often in the context of providing gas-less transactions. https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/metatx/MinimalForwarder.sol

The key functions, verify, and execute, take two arguments: ForwardRequest calldata req, and bytes calldata signature

Although conceptually I understand what each of these arguments means, it is really hard to figure the exact format /functions I need to use to construct these arguments. Does anyone have a working example of doing this using ether.js?

[zemse]

// you need a domain
const domain = {
  name: 'My App',
  version: '1',
  chainId: 1,
  verifyingContract: '0x1111111111111111111111111111111111111111'
};

// types
const types = {
  ForwardRequest: [
    { name: 'from', type: 'address' },
    { name: 'to', type: 'address' }
    { name: 'value', type: 'uint256' }
    { name: 'gas', type: 'uint256' }
    { name: 'nonce', type: 'uint256' }
    { name: 'data', type: 'bytes' }
  ]
};

const request = {
    from: '0xAddr'
    to: '0xAddr',
    value: 123,
    gas: 123
    nonce: 123,
    data: '0x1234'
}

wallet._signTypedData(domain, types, request);

You may also have a look at this post.