Hardhat

Using Hardhat to Deploy To Phron

Introduction

Hardhat is a flexible and extensible Ethereum development environment that streamlines the smart contract development process. Since Phron is Ethereum-compatible, you can use Hardhat to develop and deploy smart contracts on Phron.

Hardhat takes a task-based approach to development, where you can define and execute tasks that perform specific actions. These actions include compiling and deploying contracts, running tests, and more. Tasks are highly configurable, so you can create, customize, and execute tasks that are tailored to meet your needs.

You can also extend Hardhat's functionality through the use of plugins. Plugins are external extensions that integrate with Hardhat to provide additional features and tools for your workflow. For example, there are plugins for common Ethereum libraries, like Ethers.js and viem, a plugin that extends the Chai assertion library to include Ethereum-specific functionality, and more. All of these plugins can be used to extend your Hardhat project on Phron.

This guide will provide a brief introduction to Hardhat and show you how to use Hardhat to compile, deploy, and debug Ethereum smart contracts on the Phron TestNet.

Please note that although Hardhat comes with a Hardhat Network component, which provides a local development environment, you should use a local Phron development node instead. You can connect a Phron development node to Hardhat just like you would with any other network.

Checking Prerequisites

To get started, you will need the following:

• Have MetaMask installed and connected to Phron

• Have an account with funds. You can get DEV tokens for testing on Phron once every 24 hours from the Phron Faucet

• To test out the examples in this guide on Phron, you will need to have your own endpoint and API key, which you can get from one of the supported Endpoint Providers

Create a Hardhat Project

You will need to create a Hardhat project if you don't already have one. You can create one by completing the following steps:

1. Create a directory for your project

   mkdir hardhat && cd hardhat

2. Initialize the project, which will create a package.json file

   npm init -y

3. Install Hardhat

   npm install hardhat

4. Create a Hardhat project

   npx hardhat init

Note

npx is used to run executables installed locally in your project. Although Hardhat can be installed globally, it is recommended to install it locally in each project so that you can control the version on a project-by-project basis.

1. A menu will appear, which will allow you to create a new project or use a sample project. For this example, you can choose Create an empty hardhat.config.js, which will create a Hardhat configuration file for your project

npx hardhat init888    888                      888 888               888888    888                      888 888               888888    888                      888 888               8888888888888  8888b.  888d888 .d88888 88888b.   8888b.  888888888    888     "88b 888P"  d88" 888 888 "88b     "88b 888888    888 .d888888 888    888  888 888  888 .d888888 888888    888 888  888 888    Y88b 888 888  888 888  888 Y88b.888    888 "Y888888 888     "Y88888 888  888 "Y888888  "Y888
👷 Welcome to Hardhat v2.22.2 👷‍
 What do you want to do? …  Create a JavaScript project   Create a TypeScript project   Create a TypeScript project (with Viem)   Quit

Hardhat Configuration File

The Hardhat configuration file is the entry point into your Hardhat project. It defines various settings and options for your Hardhat project, such as the Solidity compiler version to use and the networks you can deploy your contracts to.

To start, your hardhat.config.js should resemble the following:

/** @type import('hardhat/config').HardhatUserConfig */
module.exports = {
  solidity: '0.8.20',
};

For this example, you can leave the Solidity compiler version to 0.8.20; however, if you are using a different contract that requires a newer version, don't forget to update the version here.

Next, you'll need to modify your configuration file to add the network configurations for the network you want to deploy your contract to. For Phron networks, you'll need to specify the following:

• url - the RPC endpoint of the node

• chainId - the chain ID, which is used to validate the network

• accounts - the accounts that can be used to deploy and interact with contracts. You can either enter an array of the private keys for your accounts or use an HD Wallet

For this example, the network will be Phron, but you can modify the configuration to use any of the Phron networks:

module.exports = {
  solidity: '0.8.20',
  networks: {
    phron: {
      url: 'INSERT_RPC_API_ENDPOINT', // Insert your RPC URL here
      chainId: 7744, // (hex: 0x504),
      accounts: ['INSERT_PRIVATE_KEY'],
    },
  },
};

Remember

This is for demo purposes only. Never store your private key in a JavaScript file.

If you are planning on using any plugins with your project, you'll need to install the plugin and import it into the hardhat.config.js file. Once a plugin has been imported, it becomes part of the Hardhat Runtime Environment, and you can leverage the plugin's functionality within tasks, scripts, and more.

For this example, you can install the hardhat-ethers plugin and import it into the configuration file. This plugin provides a convenient way to use the Ethers.js library to interact with the network.

npm install @nomicfoundation/hardhat-ethers ethers

Additionally, you'll need to install the hardhat-ignition-ethers plugin to enable deployment of smart contracts with Hardhat Ignition. You can install it with the following command:

npm install --save-dev @nomicfoundation/hardhat-ignition-ethers

To import both plugins, add the following require statements to the top of the Hardhat configuration file:

/** @type import('hardhat/config').HardhatUserConfig */
require('@nomicfoundation/hardhat-ethers');
require('@nomicfoundation/hardhat-ignition-ethers');

const privateKey = 'INSERT_PRIVATE_KEY';

module.exports = {
  solidity: '0.8.20',
  networks: {
    phron: {
      url: 'https://',
      chainId: 1287, // 0x507 in hex,
      accounts: [privateKey]
    }
  }
};

For more information on the available configuration options, please refer to Hardhat's documentation on Configuration.

The Contract File

Now that you've configured your project, you can begin the development process by creating your smart contract. The contract will be a simple one that will let you store a value that can be retrieved later, called Box.

To add the contract, you'll take the following steps:

1. Create a contracts directory

   mkdir contracts

2. Create a Box.sol file

   touch contracts/Box.sol

3. Open the file and add the following contract to it:

   // contracts/Box.sol
   // SPDX-License-Identifier: MIT
   pragma solidity ^0.8.1;
   
   contract Box {
       uint256 private value;
   
       // Emitted when the stored value changes
       event ValueChanged(uint256 newValue);
   
       // Stores a new value in the contract
       function store(uint256 newValue) public {
           value = newValue;
           emit ValueChanged(newValue);
       }
   
       // Reads the last stored value
       function retrieve() public view returns (uint256) {
           return value;
       }
   }

Compile the Contract

The next step is to compile the Box.sol smart contract. For this, you can use the built-in compile task, which will look for Solidity files in the contracts directory and compile them using the version and compiler settings defined in the hardhat.config.js file.

To use the compile task, all you have to do is run:

npx hardhat compile

npx hardhat compileCompiled 1 Solidity files successfully (evm target: paris).ls -lartifactscachecontractshardhat.config.jsnode_modulespackage.jsonpackage-lock.json

After compilation, an artifacts directory is created that holds the bytecode and metadata of the contract, which are .json files. It’s a good idea to add this directory to a .gitignore file.

If you make changes to the contract after you've compiled it, you can compile it again using the same command. Hardhat will look for any changes and recompile the contract. If no changes are found, nothing will be compiled. If needed, you can force a compilation using the clean task, which will clear the cache and delete the old artifacts.

Deploy the Contract

To deploy the contract, you'll use Hardhat Ignition, a declarative framework for deploying smart contracts. Hardhat Ignition is designed to make it easy to manage recurring tasks surrounding smart contract deployment and testing. For more information, be sure to check out the Hardhat Ignition docs.

To set up the proper file structure for your Ignition module, create a folder named ignition and a subdirectory called modules. Then add a new file to it called Box.js. You can take all three of these steps with the following command:

mkdir ignition ignition/modules && touch ignition/modules/Box.js

Next, you can write your Hardhat Ignition module. To get started, take the following steps:

1. Import the buildModule function from the Hardhat Ignition module

2. Export a module using buildModule

3. Use the getAccount method to select the deployer account

4. Deploy the Box contract

5. Return an object from the module. This makes the Box contract accessible for interaction in Hardhat tests and scripts

// 1.  Import the `buildModule` function from the Hardhat Ignition module
const { buildModule } = require("@nomicfoundation/hardhat-ignition/modules");

// 2. Export a module using `buildModule`
module.exports = buildModule("BoxModule", (m) => {

  // 3. Use the `getAccount` method to select the deployer account
  const deployer = m.getAccount(0);

  // 4. Deploy the `Box` contract
  const box = m.contract("Box", [], {
    from: deployer,
  });

  // 5. Return an object from the module 
  return { box };
});

To run the script and deploy the Box.sol contract, use the following command, which requires you to specify the network name as defined in your hardhat.config.js. If you don't specify a network, hardhat will deploy the contract to a local hardhat network by default.

npx hardhat ignition deploy ./ignition/modules/Box.js --network phron

Note

If you're using another Phron network, make sure that you specify the correct network. The network name needs to match how it's defined in the hardhat.config.js file.

You'll be prompted to confirm the network you wish to deploy to. After a few seconds after you confirm, the contract is deployed, and you'll see the contract address in the terminal.

npx hardhat ignition deploy ./ignition/modules/Box.js --network phron
✅ Confirm deploy to network phron (7744)? … yesHardhat Ignition 🚀
Deploying [ BoxModule ]
Batch #1Executed BoxModule#Box
[ BoxModule ] successfully deployed 🚀
Deployed Addresses
BoxModule#Box - 0xfBD78CE8C9E1169851119754C4Ea2f70AB159289

Congratulations, your contract is live! Save the address, as you will use it to interact with this contract instance in the next step.

Interact with the Contract

There are a couple of ways that you can interact with your newly deployed contract using Hardhat: you can use the console task, which spins up an interactive JavaScript console, or you can create another script and use the run task to execute it.

Using the Hardhat Console

The Hardhat console uses the same execution environment as the tasks and scripts, so it automatically uses the configurations and plugins defined in the hardhat.config.js.

To launch the Hardhat console, you can run:

npx hardhat console --network phron

Next, you can take the following steps, entering one line at a time:

1. Create a local instance of the Box.sol contract

   const Box = await ethers.getContractFactory('Box');

2. Connect the local instance to the deployed contract, using the address of the contract

   const box = await Box.attach('0xfBD78CE8C9E1169851119754C4Ea2f70AB159289');

3. Interact with the attached contract. For this example, you can call the store method and store a simple value

   await box.store(5);

The transaction will be signed by your account configured in the hardhat.config.js file and broadcasted to the network. The output should look similar to:

npx hardhat console --network phron
Welcome to Node.js v20.9.0.Type ".help" for more information. const Box = await ethers.getContractFactory('Box');undefined
const box = await Box.attach('0xfBD78CE8C9E1169851119754C4Ea2f70AB159289');undefined
await box.store(5);ContractTransactionResponse {
provider: HardhatEthersProvider { ... },
blockNumber: null,
blockHash: null,
index: undefined,
hash: '0x1c49a64a601fc5dd184f0a368a91130cb49203ec0f533c6fcf20445c68e20264',
type: 2,
to: '0xa84caB60db6541573a091e5C622fB79e175E17be',
from: '0x3B939FeaD1557C741Ff06492FD0127bd287A421e',
nonce: 87,
gasLimit: 45881n,
gasPrice: 1107421875n,
maxPriorityFeePerGas: 1n,
maxFeePerGas: 1107421875n,
data: '0x6057361d0000000000000000000000000000000000000000000000000000000000000005',
value: 0n,
chainId: 5678n,
signature: Signature { r: "0x9233b9cc4ae6879b7e08b9f1a4bfb175c8216eee0099966eca4a305c7f369ecc", s: "0x7663688633006b5a449d02cb08311569fadf2f9696bd7fe65417860a3b5fc57d", yParity: 0, networkV: null },
accessList: [],
blobVersionedHashes: null
} await box.retrieve();5n

Notice your address labeled from, the address of the contract, and the data that is being passed. Now, you can retrieve the value by running:

await box.retrieve();

You should see 5, or the value you initially stored.

Using a Script

Similarly to the deployment script, you can create a script to interact with your deployed contract, store it in the scripts directory, and run it using the built-in run task.

To get started, create a set-value.js file in the scripts directory:

mkdir scripts && touch scripts/set-value.js

Now paste the following contract into the set-value.js file:

// scripts/set-value.js
async function main() {
  // Create instance of the Box contract
  const Box = await ethers.getContractFactory('Box');

  // Connect the instance to the deployed contract
  const box = await Box.attach('0xfBD78CE8C9E1169851119754C4Ea2f70AB159289');

  // Store a new value
  await box.store(2);

  // Retrieve the value
  const value = await box.retrieve();
  console.log(`The new value is: ${value}`);
}

main()
  .then(() => process.exit(0))
  .catch(error => {
    console.error(error);
    process.exit(1);
  });

To run the script, you can use the following command:

npx hardhat run --network phron scripts/set-value.js

The script should return 2 as the value.

npx hardhat run --network phron scripts/set-value.js
The new value is: 2

Hardhat Forking

You can fork any EVM-compatible chain using Hardhat, including Phron. Forking simulates the live Phron network locally, enabling you to interact with deployed contracts on Phron in a local test environment. Since Hardhat forking is based on an EVM implementation, you can interact with the fork using standard Ethereum JSON-RPC methods supported by Phron and Hardhat.

There are some limitations to be aware of when using Hardhat forking. You cannot interact with any of the Phron precompiled contracts or their functions. Precompiles are a part of the Substrate implementation and therefore cannot be replicated in the simulated EVM environment. This prohibits you from interacting with cross-chain assets on Phron and Substrate-based functionality such as staking and governance.

There is currently an issue related to forking Phron, so in order to fix the issue, you'll need to manually patch Hardhat first. You can find out more information by following the issue on GitHub as well as the related PR.

Patching Hardhat

Before getting started, you'll need to apply a temporary patch to workaround an RPC error until Hardhat fixes the root issue. The error is as follows:

Error HH604: Error running JSON-RPC server: Invalid JSON-RPC response's result.

Errors: Invalid value null supplied to : RpcBlockWithTransactions | null/transactions: RpcTransaction Array/0: RpcTransaction/accessList: Array<{ address: DATA, storageKeys: Array<DATA> | null }> | undefined, Invalid value null supplied to : RpcBlockWithTransactions | null/transactions: RpcTransaction Array/1: RpcTransaction/accessList: Array<{ address: DATA, storageKeys: Array<DATA> | null }> | undefined, Invalid value null supplied to : RpcBlockWithTransactions | null/transactions: RpcTransaction Array/2: RpcTransaction/accessList: Array<{ address: DATA, storageKeys: Array<DATA> | null }> | undefined

To patch Hardhat, you'll need to open the node_modules/hardhat/internal/hardhat-network/jsonrpc/client.js file of your project. Next, you'll add an addAccessList function and update the _perform and _performBatch functions.

To get started, you can remove the preexisting _perform and _performBatch functions and, in their place, add the following code snippet:

  addAccessList(method, rawResult) {
    if (
      method.startsWith('eth_getBlock') &&
      rawResult &&
      rawResult.transactions?.length
    ) {
      rawResult.transactions.forEach((t) => {
        if (t.accessList == null) t.accessList = [];
      });
    }
  }
  async _perform(method, params, tType, getMaxAffectedBlockNumber) {
    const cacheKey = this._getCacheKey(method, params);
    const cachedResult = this._getFromCache(cacheKey);
    if (cachedResult !== undefined) {
      return cachedResult;
    }
    if (this._forkCachePath !== undefined) {
      const diskCachedResult = await this._getFromDiskCache(
        this._forkCachePath,
        cacheKey,
        tType
      );
      if (diskCachedResult !== undefined) {
        this._storeInCache(cacheKey, diskCachedResult);
        return diskCachedResult;
      }
    }
    const rawResult = await this._send(method, params);
    this.addAccessList(method, rawResult);
    const decodedResult = (0, decodeJsonRpcResponse_1.decodeJsonRpcResponse)(
      rawResult,
      tType
    );
    const blockNumber = getMaxAffectedBlockNumber(decodedResult);
    if (this._canBeCached(blockNumber)) {
      this._storeInCache(cacheKey, decodedResult);
      if (this._forkCachePath !== undefined) {
        await this._storeInDiskCache(this._forkCachePath, cacheKey, rawResult);
      }
    }
    return decodedResult;
  }
  async _performBatch(batch, getMaxAffectedBlockNumber) {
    // Perform Batch caches the entire batch at once.
    // It could implement something more clever, like caching per request
    // but it's only used in one place, and those other requests aren't
    // used anywhere else.
    const cacheKey = this._getBatchCacheKey(batch);
    const cachedResult = this._getFromCache(cacheKey);
    if (cachedResult !== undefined) {
      return cachedResult;
    }
    if (this._forkCachePath !== undefined) {
      const diskCachedResult = await this._getBatchFromDiskCache(
        this._forkCachePath,
        cacheKey,
        batch.map((b) => b.tType)
      );
      if (diskCachedResult !== undefined) {
        this._storeInCache(cacheKey, diskCachedResult);
        return diskCachedResult;
      }
    }
    const rawResults = await this._sendBatch(batch);
    const decodedResults = rawResults.map((result, i) => {
      this.addAccessList(batch[i].method, result);
      return (0, decodeJsonRpcResponse_1.decodeJsonRpcResponse)(
        result,
        batch[i].tType
      );
    });
    const blockNumber = getMaxAffectedBlockNumber(decodedResults);
    if (this._canBeCached(blockNumber)) {
      this._storeInCache(cacheKey, decodedResults);
      if (this._forkCachePath !== undefined) {
        await this._storeInDiskCache(this._forkCachePath, cacheKey, rawResults);
      }
    }
    return decodedResults;
  }

Then you can use patch-package to automatically patch the package by running the following command:

npx patch-package hardhat

A patches directory will be created, and now you should be all set to fork Phron without running into any errors.

Forking Phron

You can fork Phron from the command line or configure your Hardhat project to always run the fork from your hardhat.config.js file. To fork Phron, you will need to have your own endpoint and API key, which you can get from one of the supported Endpoint Providers.

To fork Phron from the command line, you can run the following command from within your Hardhat project directory:

npx hardhat node --fork INSERT_RPC_API_ENDPOINT

If you prefer to configure your Hardhat project, you can update your hardhat.config.js file with the following configurations:

...
networks: {
  hardhat: {
    forking: {
      url: 'INSERT_RPC_API_ENDPOINT',
    },
  },
},
...

When you spin up the Hardhat fork, you'll have 20 development accounts that are pre-funded with 10,000 test tokens. The forked instance is available at http://127.0.0.1:8545/. The output in your terminal should resemble the following:

Private Key: Oxdbda1821b80551c9d65939329250298aa3472ba22feea921c0cf5d620ea67b97Account #9: Oxa0Ee7A142d267C1f36714E4a8F75612F20a79720 (10000 ETH)Private Key: 0x2a871d0798f97d79848a013d4936a73bf4cc922c825d33c1cf7073dff6d409c6Account #10: OxBcd4042DE499D14e55001CcbB24a551F3b954096 (10000 ETH)Private Key: Oxf214f2b2cd398c806f84e317254e0f0b801d0643303237d97a22a48e01628897Account #11: 0x71bE63f3384f5fb98995898A86B02Fb2426c5788 (10000 ETH)Private Key: 0x701b615bbdfb9de65240bc28bd21bbc0d996645a3dd57e7b12bc2bdf6f192c82Account #12: OxFABBOac9d68B0B445fB7357272F202C5651694a (10000 ETH)Private Key: Oxa267530f49f8280200edf313ee7af6b827f2a8bce2897751d06a843f644967b1Account #13: 0x1CBd3b2770909D4e10f157cABC84C7264073C9Ec (10000 ETH)Private Key: 0x47c99abed3324a2707c28affff1267e45918ec8c3f20b8aa892e8b065d2942ddAccount #14: OxdF3e18d64BC6A983f673Ab319CCaE4f1a5707097 (10000 ETH)Private Key: Oxc526ee95bf44d8fc405a158bb884d9d1238d990612e9f33d006bb0789009aaaAccount #15: Oxcd3B766CCDd6AE721141F452C550Ca635964ce71 (10000 ETH)Private Key: 0x8166f546bab6da521a8369cab06c5d2b9e46670292d85c875ee9ec20e84ffb61Account #16: 0×2546BcD3c84621e976D8185a91A922aE77ECEc30 (10000 ETH)Private Key: Oxea6c44ac03bff858b476bba40716402b03e41b8e97e276d1baec7c37d42484a0Account #17: OxbDA5747bFD65F08deb54cb465eB87D40e51B197E (10000 ETH)Private Key: 0x689af8efa8c651a91ad287602527f3af2fe9f6501a7ac4b06166765a93e037fdAccount #18: OxdD2FD4581271e230360230F9337D5c0430Bf44C0 (10000 ETH)Private Key: Oxde9be858da4a475276426320d5e9262ecfc3ba460bfac56360bfa6c4c28b4ee0Account #19: 0×8626f6940E2eb28930eFb4CeF49B2d1F2C9C1199 (10000 ETH)Private Key: Oxdf57089febbacf7ba0bc227dafbffa9fc08a93fdc68e1e42411a14efcf23656eWARNING: These accounts, and their private keys, are publicly known.
Any funds sent to them on Mainnet or any other live network WILL BE LOST.

To verify you have forked the network, you can query the latest block number:

curl --data '{"method":"eth_blockNumber","params":[],"id":1,"jsonrpc":"2.0"}' -H "Content-Type: application/json" -X POST localhost:8545 

If you convert the result from hex to decimal, you should get the latest block number from the time you forked the network. You can cross-reference the block number using a block explorer.

From here, you can deploy new contracts to your forked instance of Phron or interact with contracts already deployed by creating a local instance of the deployed contract.

To interact with an already deployed contract, you can create a new script in the scripts directory using ethers. Because you'll be running it with Hardhat, you don't need to import any libraries. Inside the script, you can access a live contract on the network using the following snippet:

const hre = require('hardhat');

async function main() {
  const provider = new ethers.JsonRpcProvider(
    'http://127.0.0.1:8545/'
  );

  const contract = new ethers.Contract(
    'INSERT_CONTRACT_ADDRESS',
    'INSERT_CONTRACT_ABI',
    provider
  );
}

main().catch((error) => {
  console.error(error);
  process.exitCode = 1;
});

This tutorial is for educational purposes only. As such, any contracts or code created in this tutorial should not be used in production.The information presented herein has been provided by third parties and is made available solely for general information purposes. Phron does not endorse any project listed and described on the Phron Doc Website (https://docs.Phron.ai/). Phron does not warrant the accuracy, completeness or usefulness of this information. Any reliance you place on such information is strictly at your own risk. Phron disclaims all liability and responsibility arising from any reliance placed on this information by you or by anyone who may be informed of any of its contents. All statements and/or opinions expressed in these materials are solely the responsibility of the person or entity providing those materials and do not necessarily represent the opinion of Phron. The information should not be construed as professional or financial advice of any kind. Advice from a suitably qualified professional should always be sought in relation to any particular matter or circumstance. The information herein may link to or integrate with other websites operated or content provided by third parties, and such other websites may link to this website. Phron has no control over any such other websites or their content and will have no liability arising out of or related to such websites or their content. The existence of any such link does not constitute an endorsement of such websites, the content of the websites, or the operators of the websites. These links are being provided to you only as a convenience and you release and hold Phron harmless from any and all liability arising from your use of this information or the information provided by any third-party website or service.