Fhenix Hardhat Plugin

Fhenix Hardhat Plugin is designed to extend your Hardhat environment with additional capabilities focused on Fhenix. It integrates seamlessly with your Hardhat projects to provide a local Fhenix environment, including customized network configuration and utilities for managing funds and permits within your blockchain applications.

See also fhenix-hardhat-docker and fhenix-hardhat-network for the full experience of Fhenix-compatible extensions.

Features

• Local Fhenix Environment: Automatically sets up a local Fhenix network configuration within Hardhat, allowing for easy deployment and interaction with Fhenix contracts.
• Faucet Integration: Enables developers to easily obtain funds for testing purposes through a simple API call to a local faucet.
• Permit Management: Simplifies the process of creating and storing permit signatures required for transactions, reducing the complexity of interacting with contracts that require permissions.
• Contract Security Checks: Checks for Fhenix-related potential vulnerabilities in your contracts.
• Hardhat Network Enhancements: Adds support for simulated FHE operations in the built-in Hardhat network.

If you want to see a full example in action, check out our Hardhat Example Template!

Installation

To use FhenixJS in your Hardhat project, first install the plugin via npm (or your favorite package manager):

pnpm install fhenix-hardhat-plugin

If you wish to run your own local dev environment, please install the fhenix-hardhat-docker plugin as well.

pnpm install fhenix-hardhat-docker

Or, if you use then built-in Hardhat network:

pnpm install fhenix-hardhat-network

Setup

After installation, import the plugin in your Hardhat configuration file (e.g., hardhat.config.js):

require("fhenix-hardhat-plugin");
// if using the docker plugin
require("fhenix-hardhat-docker");
// if using the network plugin
require("fhenix-hardhat-docker");

or if you are using TypeScript, in your hardhat.config.ts:

import "fhenix-hardhat-plugin";
// if using the docker plugin
import "fhenix-hardhat-docker";
// if using the network plugin
import "fhenix-hardhat-network";

Configuration

Network Configuration

The plugin automatically adds a localfhenix network configuration to your Hardhat project. This configuration is designed for local development and includes settings such as gas estimates, accounts, and the local network URL.

To target this network, simply add --network localfhenix to your hardhat commands, or set it as the default.

Alternatively, to use the build-in hardhat network, either do nothing if you're running the in-process network, or add --network localhost to your hardhat commands if you're running the standalone network via pnpm hardhat node, just as you would without the fhenix-hardhat-network plugin.

Using FhenixJS from Hardhat Runtime Environment

After importing fhenix-hardhat-plugin hardhat will automatically extend the Hardhat Runtime Environment (HRE) with a fhenixjs object, providing access to Fhenix-specific functionality:

• Use the fhenixjs object directly to encrypt, unseal or manage permits.
• getFunds(address: string): Request funds from the local faucet for the specified address.
• createPermit(contractAddress: string, provider?: SupportedProvider): Create and store a permit for interacting with a contract.

Usage

Local Dev Environment

To set up a localfhenix instance, simply import fhenix-hardhat-docker. This will add two new hardhat tasks:

• localfhenix:start To start a local dev environment using docker. By default, the instance will listen for rpc connections on port 42069
• localfhenix:stop Stops the docker container

To start the container:

pnpm hardhat localfhenix:start

If starting the instance was successful, you should see the message: Started LocalFhenix successfully at 127.0.0.1:42069.

To stop the running container:

pnpm hardhat localfhenix:stop

Which will result in Successfully shut down LocalFhenix

Requesting Funds

To request funds from the local faucet for an address, use the getFunds method:

await hre.fhenixjs.getFunds("your_wallet_address");

Or use the usefaucet task. Omitting the address will send to the first account in the configured wallet:

pnpm hardhat run task:fhenix:usefaucet [--address <address>]

Or you can specify the account number if you want to specify more than one account for the mnemonic specified

pnpm task:fhenix:usefaucet --account <number>

If you're not using localfhenix, you have to specify the faucet url yourself:

pnpm task:fhenix:usefaucet --url <faucet-url>

Encryption

const encyrptedAmount = await fhenixjs.encrypt_uint32(15);

Creating a Permit

To create a permit for a contract, use the createPermit method:

const permit = await hre.fhenixjs.createPermit("contract_address");

See FhenixJs documentation for more on using the fhenixjs object.

Support

For issues, suggestions, or contributions, please open an issue or pull request in the GitHub repository.