# INTRODUCTION

This repository implements a generic EIP-2771 compliant forwarder that is fully future proof and universal.

It actually comes with 2 different implementation, the UniversalForwarder and the ForwarderRegistry.

# UniversalForwarder

The UniversalForwarder is the most simple and generic forwarder possible. It requires zero storage read or write but approval are for eternity.

It does that by requiring the caller / relayer to always provide a signature along the call.

# ForwarderRegistry

The ForwarderRegistry instead keep a record of approved forwarder for each user. It thus comes at a higher gas cost overall.

Its advantages is that user are able to revoke approved forwarder if desired.

# Usage

The reposiroty is also a npm package [ethereum-universal-forwarder](https://www.npmjs.com/package/ethereum-universal-forwarder) and contains abstract contract you can import in your code to get started with these forwarders.

If you use [hardhat-deploy](https://github.com/wighawag/hardhat-deploy), it also come with exported deploy script that you can use to have the contract available in your test or specific networks very easily.

An example repo can be found here : https://github.com/wighawag/test-ethereum-universal-forwarder

# DEVELOPMENT

## INSTALL

```bash
yarn
```

## TEST

```bash
yarn test
```

## SCRIPTS

Here is the list of npm scripts you can execute:

Some of them relies on [./\_scripts.js](./_scripts.js) to allow parameterizing it via command line argument (have a look inside if you need modifications)
<br/><br/>

`yarn prepare`

As a standard lifecycle npm script, it is executed automatically upon install. It generate config file and typechain to get you started with type safe contract interactions
<br/><br/>

`yarn lint`, `yarn lint:fix`, `yarn format` and `yarn format:fix`

These will lint and format check your code. the `:fix` version will modifiy the files to match the requirement specified in `.eslintrc` and `.prettierrc.`
<br/><br/>

`yarn compile`

These will compile your contracts
<br/><br/>

`yarn void:deploy`

This will deploy your contracts on the in-memory hardhat network and exit, leaving no trace. quick way to ensure deployments work as intended without consequences
<br/><br/>

`yarn test [mocha args...]`

These will execute your tests using mocha. you can pass extra arguments to mocha
<br/><br/>

`yarn coverage`

These will produce a coverage report in the `coverage/` folder
<br/><br/>

`yarn gas`

These will produce a gas report for function used in the tests
<br/><br/>

`yarn dev`

These will run a local hardhat network on `localhost:8545` and deploy your contracts on it. Plus it will watch for any changes and redeploy them.
<br/><br/>

`yarn local:dev`

This assumes a local node it running on `localhost:8545`. It will deploy your contracts on it. Plus it will watch for any changes and redeploy them.
<br/><br/>

`yarn execute <network> <file.ts> [args...]`

This will execute the script `<file.ts>` against the specified network
<br/><br/>

`yarn deploy <network> [args...]`

This will deploy the contract on the specified network.

Behind the scene it uses `hardhat deploy` command so you can append any argument for it
<br/><br/>

`yarn export <network> <file.json>`

This will export the abi+address of deployed contract to `<file.json>`
<br/><br/>

`yarn fork:execute <network> [--blockNumber <blockNumber>] [--deploy] <file.ts> [args...]`

This will execute the script `<file.ts>` against a temporary fork of the specified network

if `--deploy` is used, deploy scripts will be executed
<br/><br/>

`yarn fork:deploy <network> [--blockNumber <blockNumber>] [args...]`

This will deploy the contract against a temporary fork of the specified network.

Behind the scene it uses `hardhat deploy` command so you can append any argument for it
<br/><br/>

`yarn fork:test <network> [--blockNumber <blockNumber>] [mocha args...]`

This will test the contract against a temporary fork of the specified network.
<br/><br/>

`yarn fork:dev <network> [--blockNumber <blockNumber>] [args...]`

This will deploy the contract against a fork of the specified network and it will keep running as a node.

Behind the scene it uses `hardhat node` command so you can append any argument for it