Hardhat Developer Workflow¶

by Kevin Neilson & Erin Shaben

Introduction¶

In this tutorial, we'll walk through the Hardhat development environment in the context of launching a pooled staking DAO contract. We'll walk through the typical developer workflow in detail from start to finish.

We'll assemble the components of the staking DAO and compile the necessary contracts. Then, we'll build a test suite with a variety of test cases relevant to our staking DAO, and run it against a local development node. Finally, we'll deploy the staking DAO to both Moonbase Alpha and Moonbeam and verify the contracts via the Hardhat Etherscan plugin. If this is your first time exploring Hardhat, you may wish to start with the introduction to Hardhat guide.

The information presented herein is for informational purposes only and has been provided by third parties. Moonbeam does not endorse any project listed and described on the Moonbeam docs website (https://docs.moonbeam.network/).

Checking Prerequisites¶

To get started, you will need the following:

• A Moonbase Alpha account funded with DEV. You can get DEV tokens for testing on Moonbase Alpha once every 24 hours from the Moonbase Alpha Faucet
• A Moonscan API Key
• For the Testing section, you'll need to have a local Moonbeam node up and running
• To test out the examples in this guide on Moonbeam or Moonriver, you will need to have your own endpoint and API key, which you can get from one of the supported Endpoint Providers

Creating 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 stakingDAO && cd stakingDAO
   

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

   npm init -y
   

3. Install Hardhat

   npm install hardhat
   

4. Create a 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.

5. 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

This will create a Hardhat config file (hardhat.config.js) in your project directory.

Add Smart Contracts¶

The smart contract featured in this tutorial is more complex than the one in the Introduction to Hardhat but the nature of the contract means it's perfect to demonstrate some of the advanced capabilities of Hardhat. DelegationDAO.sol is a pooled staking DAO that uses StakingInterface.sol to autonomously delegate to a collator when it reaches a determined threshold. Pooled staking contracts such as DelegationDAO.sol allow delegators with less than the protocol minimum bond to join together to delegate their pooled funds and earn a share of staking rewards.

To get started, take the following steps:

1. Create a contracts directory to hold your project's smart contracts

   mkdir contracts
   

2. Create a new file called DelegationDAO.sol

   touch contracts/DelegationDAO.sol
   

3. Copy and paste the contents of DelegationDAO.sol into DelegationDAO.sol

   DelegationDAO.sol

   // SPDX-License-Identifier: GPL-3.0-only
   // This is a PoC to use the staking precompile wrapper as a Solidity developer.
   pragma solidity >=0.8.0;
   
   import "./StakingInterface.sol";
   import "@openzeppelin/contracts/access/AccessControl.sol";
   import "@openzeppelin/contracts/utils/math/SafeMath.sol";
   import "@openzeppelin/contracts/utils/Address.sol";
   
   contract DelegationDAO is AccessControl {
       using SafeMath for uint256;
   
       // Role definition for contract members
       bytes32 public constant MEMBER = keccak256("MEMBER");
   
       // Possible states for the DAO to be in:
       // COLLECTING: the DAO is collecting funds before creating a delegation once the minimum delegation stake has been reached
       // STAKING: the DAO has an active delegation
       // REVOKING: the DAO has scheduled a delegation revoke
       // REVOKED: the scheduled revoke has been executed
       enum daoState {
           COLLECTING,
           STAKING,
           REVOKING,
           REVOKED
       }
   
       // Current state that the DAO is in
       daoState public currentState;
   
       // Member stakes (doesnt include rewards, represents member shares)
       mapping(address => uint256) public memberStakes;
   
       // Total Staking Pool (doesnt include rewards, represents total shares)
       uint256 public totalStake;
   
       // The ParachainStaking wrapper at the known pre-compile address. This will be used to make
       // all calls to the underlying staking solution
       ParachainStaking public staking;
   
       // Minimum Delegation Amount
       uint256 public constant minDelegationStk = 5 ether;
   
       // Moonbeam Staking Precompile address
       address public constant stakingPrecompileAddress =
           0x0000000000000000000000000000000000000800;
   
       // The collator that this DAO is currently nominating
       address public target;
   
       // Event for a member deposit
       event deposit(address indexed _from, uint _value);
   
       // Event for a member withdrawal
       event withdrawal(address indexed _from, address indexed _to, uint _value);
   
       // Initialize a new DelegationDao dedicated to delegating to the given collator target.
       constructor(address _target, address admin) {
           //Sets the collator that this DAO nominating
           target = _target;
   
           // Initializes Moonbeam's parachain staking precompile
           staking = ParachainStaking(stakingPrecompileAddress);
   
           //Initializes Roles
           _setupRole(DEFAULT_ADMIN_ROLE, admin);
           _setupRole(MEMBER, admin);
   
           //Initialize the DAO state
           currentState = daoState.COLLECTING;
       }
   
       // Grant a user the role of admin
       function grant_admin(
           address newAdmin
       ) public onlyRole(DEFAULT_ADMIN_ROLE) onlyRole(MEMBER) {
           grantRole(DEFAULT_ADMIN_ROLE, newAdmin);
           grantRole(MEMBER, newAdmin);
       }
   
       // Grant a user membership
       function grant_member(
           address newMember
       ) public onlyRole(DEFAULT_ADMIN_ROLE) {
           grantRole(MEMBER, newMember);
       }
   
       // Revoke a user membership
       function remove_member(
           address payable exMember
       ) public onlyRole(DEFAULT_ADMIN_ROLE) {
           revokeRole(MEMBER, exMember);
       }
   
       // Increase member stake via a payable function and automatically stake the added amount if possible
       function add_stake() external payable onlyRole(MEMBER) {
           if (currentState == daoState.STAKING) {
               // Sanity check
               if (!staking.isDelegator(address(this))) {
                   revert("The DAO is in an inconsistent state.");
               }
               memberStakes[msg.sender] = memberStakes[msg.sender].add(msg.value);
               totalStake = totalStake.add(msg.value);
               emit deposit(msg.sender, msg.value);
               staking.delegatorBondMore(target, msg.value);
           } else if (currentState == daoState.COLLECTING) {
               memberStakes[msg.sender] = memberStakes[msg.sender].add(msg.value);
               totalStake = totalStake.add(msg.value);
               emit deposit(msg.sender, msg.value);
               if (totalStake < minDelegationStk) {
                   return;
               } else {
                   //initialiate the delegation and change the state
                   staking.delegate(
                       target,
                       address(this).balance,
                       staking.candidateDelegationCount(target),
                       staking.delegatorDelegationCount(address(this))
                   );
                   currentState = daoState.STAKING;
               }
           } else {
               revert("The DAO is not accepting new stakes in the current state.");
           }
       }
   
       // Function for a user to withdraw their stake
       function withdraw(address payable account) public onlyRole(MEMBER) {
           require(
               currentState != daoState.STAKING,
               "The DAO is not in the correct state to withdraw."
           );
           if (currentState == daoState.REVOKING) {
               bool result = execute_revoke();
               require(result, "Schedule revoke delay is not finished yet.");
           }
           if (
               currentState == daoState.REVOKED ||
               currentState == daoState.COLLECTING
           ) {
               //Sanity checks
               if (staking.isDelegator(address(this))) {
                   revert("The DAO is in an inconsistent state.");
               }
               require(totalStake != 0, "Cannot divide by zero.");
               //Calculate the withdrawal amount including staking rewards
               uint amount = address(this)
                   .balance
                   .mul(memberStakes[msg.sender])
                   .div(totalStake);
               require(
                   check_free_balance() >= amount,
                   "Not enough free balance for withdrawal."
               );
               Address.sendValue(account, amount);
               totalStake = totalStake.sub(memberStakes[msg.sender]);
               memberStakes[msg.sender] = 0;
               emit withdrawal(msg.sender, account, amount);
           }
       }
   
       // Schedule revoke, admin only
       function schedule_revoke() public onlyRole(DEFAULT_ADMIN_ROLE) {
           require(
               currentState == daoState.STAKING,
               "The DAO is not in the correct state to schedule a revoke."
           );
           staking.scheduleRevokeDelegation(target);
           currentState = daoState.REVOKING;
       }
   
       // Try to execute the revoke, returns true if it succeeds, false if it doesn't
       function execute_revoke() internal onlyRole(MEMBER) returns (bool) {
           require(
               currentState == daoState.REVOKING,
               "The DAO is not in the correct state to execute a revoke."
           );
           staking.executeDelegationRequest(address(this), target);
           if (staking.isDelegator(address(this))) {
               return false;
           } else {
               currentState = daoState.REVOKED;
               return true;
           }
       }
   
       // Check how much free balance the DAO currently has. It should be the staking rewards if the DAO state is anything other than REVOKED or COLLECTING.
       function check_free_balance()
           public
           view
           onlyRole(MEMBER)
           returns (uint256)
       {
           return address(this).balance;
       }
   
       // Change the collator target, admin only
       function change_target(
           address newCollator
       ) public onlyRole(DEFAULT_ADMIN_ROLE) {
           require(
               currentState == daoState.REVOKED ||
                   currentState == daoState.COLLECTING,
               "The DAO is not in the correct state to change staking target."
           );
           target = newCollator;
       }
   
       // Reset the DAO state back to COLLECTING, admin only
       function reset_dao() public onlyRole(DEFAULT_ADMIN_ROLE) {
           currentState = daoState.COLLECTING;
       }
   }
   

4. Create a new file called StakingInterface.sol in the contracts directory

   touch contracts/StakingInterface.sol
   

5. Copy and paste the contents of StakingInterface.sol into StakingInterface.sol

   StakingInterface.sol

   // SPDX-License-Identifier: GPL-3.0-only
   pragma solidity >=0.8.3;
   
   /// @dev The ParachainStaking contract's address.
   address constant PARACHAIN_STAKING_ADDRESS = 0x0000000000000000000000000000000000000800;
   
   /// @dev The ParachainStaking contract's instance.
   ParachainStaking constant PARACHAIN_STAKING_CONTRACT = ParachainStaking(
       PARACHAIN_STAKING_ADDRESS
   );
   
   /// @author The Moonbeam Team
   /// @title Pallet Parachain Staking Interface
   /// @dev The interface through which Solidity contracts will interact with Parachain Staking
   /// We follow this same interface including four-byte function selectors, in the precompile that
   /// wraps the pallet
   /// @custom:address 0x0000000000000000000000000000000000000800
   interface ParachainStaking {
       /// @dev Check whether the specified address is currently a staking delegator
       /// @custom:selector fd8ab482
       /// @param delegator the address that we want to confirm is a delegator
       /// @return A boolean confirming whether the address is a delegator
       function isDelegator(address delegator) external view returns (bool);
   
       /// @dev Check whether the specified address is currently a collator candidate
       /// @custom:selector d51b9e93
       /// @param candidate the address that we want to confirm is a collator andidate
       /// @return A boolean confirming whether the address is a collator candidate
       function isCandidate(address candidate) external view returns (bool);
   
       /// @dev Check whether the specifies address is currently a part of the active set
       /// @custom:selector 740d7d2a
       /// @param candidate the address that we want to confirm is a part of the active set
       /// @return A boolean confirming whether the address is a part of the active set
       function isSelectedCandidate(
           address candidate
       ) external view returns (bool);
   
       /// @dev Total points awarded to all collators in a particular round
       /// @custom:selector 9799b4e7
       /// @param round the round for which we are querying the points total
       /// @return The total points awarded to all collators in the round
       function points(uint256 round) external view returns (uint256);
   
       /// @dev Total points awarded to a specific collator in a particular round.
       /// A value of `0` may signify that no blocks were produced or that the storage for that round has been removed
       /// @custom:selector bfea66ac
       /// @param round the round for which we are querying the awarded points
       /// @param candidate The candidate to whom the points are awarded
       /// @return The total points awarded to the collator for the provided round
       function awardedPoints(
           uint32 round,
           address candidate
       ) external view returns (uint32);
   
       /// @dev The amount delegated in support of the candidate by the delegator
       /// @custom:selector a73e51bc
       /// @param delegator Who made this delegation
       /// @param candidate The candidate for which the delegation is in support of
       /// @return The amount of the delegation in support of the candidate by the delegator
       function delegationAmount(
           address delegator,
           address candidate
       ) external view returns (uint256);
   
       /// @dev Whether the delegation is in the top delegations
       /// @custom:selector 91cc8657
       /// @param delegator Who made this delegation
       /// @param candidate The candidate for which the delegation is in support of
       /// @return If delegation is in top delegations (is counted)
       function isInTopDelegations(
           address delegator,
           address candidate
       ) external view returns (bool);
   
       /// @dev Get the minimum delegation amount
       /// @custom:selector 02985992
       /// @return The minimum delegation amount
       function minDelegation() external view returns (uint256);
   
       /// @dev Get the CandidateCount weight hint
       /// @custom:selector a9a981a3
       /// @return The CandidateCount weight hint
       function candidateCount() external view returns (uint256);
   
       /// @dev Get the current round number
       /// @custom:selector 146ca531
       /// @return The current round number
       function round() external view returns (uint256);
   
       /// @dev Get the CandidateDelegationCount weight hint
       /// @custom:selector 2ec087eb
       /// @param candidate The address for which we are querying the nomination count
       /// @return The number of nominations backing the collator
       function candidateDelegationCount(
           address candidate
       ) external view returns (uint32);
   
       /// @dev Get the CandidateAutoCompoundingDelegationCount weight hint
       /// @custom:selector 905f0806
       /// @param candidate The address for which we are querying the auto compounding
       ///     delegation count
       /// @return The number of auto compounding delegations
       function candidateAutoCompoundingDelegationCount(
           address candidate
       ) external view returns (uint32);
   
       /// @dev Get the DelegatorDelegationCount weight hint
       /// @custom:selector 067ec822
       /// @param delegator The address for which we are querying the delegation count
       /// @return The number of delegations made by the delegator
       function delegatorDelegationCount(
           address delegator
       ) external view returns (uint256);
   
       /// @dev Get the selected candidates for the current round
       /// @custom:selector bcf868a6
       /// @return The selected candidate accounts
       function selectedCandidates() external view returns (address[] memory);
   
       /// @dev Whether there exists a pending request for a delegation made by a delegator
       /// @custom:selector 3b16def8
       /// @param delegator the delegator that made the delegation
       /// @param candidate the candidate for which the delegation was made
       /// @return Whether a pending request exists for such delegation
       function delegationRequestIsPending(
           address delegator,
           address candidate
       ) external view returns (bool);
   
       /// @dev Whether there exists a pending exit for candidate
       /// @custom:selector 43443682
       /// @param candidate the candidate for which the exit request was made
       /// @return Whether a pending request exists for such delegation
       function candidateExitIsPending(
           address candidate
       ) external view returns (bool);
   
       /// @dev Whether there exists a pending bond less request made by a candidate
       /// @custom:selector d0deec11
       /// @param candidate the candidate which made the request
       /// @return Whether a pending bond less request was made by the candidate
       function candidateRequestIsPending(
           address candidate
       ) external view returns (bool);
   
       /// @dev Returns the percent value of auto-compound set for a delegation
       /// @custom:selector b4d4c7fd
       /// @param delegator the delegator that made the delegation
       /// @param candidate the candidate for which the delegation was made
       /// @return Percent of rewarded amount that is auto-compounded on each payout
       function delegationAutoCompound(
           address delegator,
           address candidate
       ) external view returns (uint8);
   
       /// @dev Join the set of collator candidates
       /// @custom:selector 1f2f83ad
       /// @param amount The amount self-bonded by the caller to become a collator candidate
       /// @param candidateCount The number of candidates in the CandidatePool
       function joinCandidates(uint256 amount, uint256 candidateCount) external;
   
       /// @dev Request to leave the set of collator candidates
       /// @custom:selector b1a3c1b7
       /// @param candidateCount The number of candidates in the CandidatePool
       function scheduleLeaveCandidates(uint256 candidateCount) external;
   
       /// @dev Execute due request to leave the set of collator candidates
       /// @custom:selector 3867f308
       /// @param candidate The candidate address for which the pending exit request will be executed
       /// @param candidateDelegationCount The number of delegations for the candidate to be revoked
       function executeLeaveCandidates(
           address candidate,
           uint256 candidateDelegationCount
       ) external;
   
       /// @dev Cancel request to leave the set of collator candidates
       /// @custom:selector 9c76ebb4
       /// @param candidateCount The number of candidates in the CandidatePool
       function cancelLeaveCandidates(uint256 candidateCount) external;
   
       /// @dev Temporarily leave the set of collator candidates without unbonding
       /// @custom:selector a6485ccd
       function goOffline() external;
   
       /// @dev Rejoin the set of collator candidates if previously had called `goOffline`
       /// @custom:selector 6e5b676b
       function goOnline() external;
   
       /// @dev Request to bond more for collator candidates
       /// @custom:selector a52c8643
       /// @param more The additional amount self-bonded
       function candidateBondMore(uint256 more) external;
   
       /// @dev Request to bond less for collator candidates
       /// @custom:selector 60744ae0
       /// @param less The amount to be subtracted from self-bond and unreserved
       function scheduleCandidateBondLess(uint256 less) external;
   
       /// @dev Execute pending candidate bond request
       /// @custom:selector 2e290290
       /// @param candidate The address for the candidate for which the request will be executed
       function executeCandidateBondLess(address candidate) external;
   
       /// @dev Cancel pending candidate bond request
       /// @custom:selector b5ad5f07
       function cancelCandidateBondLess() external;
   
       /// @notice DEPRECATED use delegateWithAutoCompound instead for lower weight and better UX
       /// @dev Make a delegation in support of a collator candidate
       /// @custom:selector 829f5ee3
       /// @param candidate The address of the supported collator candidate
       /// @param amount The amount bonded in support of the collator candidate
       /// @param candidateDelegationCount The number of delegations in support of the candidate
       /// @param delegatorDelegationCount The number of existing delegations by the caller
       function delegate(
           address candidate,
           uint256 amount,
           uint256 candidateDelegationCount,
           uint256 delegatorDelegationCount
       ) external;
   
       /// @dev Make a delegation in support of a collator candidate
       /// @custom:selector 4b8bc9bf
       /// @param candidate The address of the supported collator candidate
       /// @param amount The amount bonded in support of the collator candidate
       /// @param autoCompound The percent of reward that should be auto-compounded
       /// @param candidateDelegationCount The number of delegations in support of the candidate
       /// @param candidateAutoCompoundingDelegationCount The number of auto-compounding delegations
       /// in support of the candidate
       /// @param delegatorDelegationCount The number of existing delegations by the caller
       function delegateWithAutoCompound(
           address candidate,
           uint256 amount,
           uint8 autoCompound,
           uint256 candidateDelegationCount,
           uint256 candidateAutoCompoundingDelegationCount,
           uint256 delegatorDelegationCount
       ) external;
   
       /// @dev Request to revoke an existing delegation
       /// @custom:selector 1a1c740c
       /// @param candidate The address of the collator candidate which will no longer be supported
       function scheduleRevokeDelegation(address candidate) external;
   
       /// @dev Bond more for delegators with respect to a specific collator candidate
       /// @custom:selector 0465135b
       /// @param candidate The address of the collator candidate for which delegation shall increase
       /// @param more The amount by which the delegation is increased
       function delegatorBondMore(address candidate, uint256 more) external;
   
       /// @dev Request to bond less for delegators with respect to a specific collator candidate
       /// @custom:selector c172fd2b
       /// @param candidate The address of the collator candidate for which delegation shall decrease
       /// @param less The amount by which the delegation is decreased (upon execution)
       function scheduleDelegatorBondLess(
           address candidate,
           uint256 less
       ) external;
   
       /// @dev Execute pending delegation request (if exists && is due)
       /// @custom:selector e98c8abe
       /// @param delegator The address of the delegator
       /// @param candidate The address of the candidate
       function executeDelegationRequest(
           address delegator,
           address candidate
       ) external;
   
       /// @dev Cancel pending delegation request (already made in support of input by caller)
       /// @custom:selector c90eee83
       /// @param candidate The address of the candidate
       function cancelDelegationRequest(address candidate) external;
   
       /// @dev Sets an auto-compound value for a delegation
       /// @custom:selector faa1786f
       /// @param candidate The address of the supported collator candidate
       /// @param value The percent of reward that should be auto-compounded
       /// @param candidateAutoCompoundingDelegationCount The number of auto-compounding delegations
       /// in support of the candidate
       /// @param delegatorDelegationCount The number of existing delegations by the caller
       function setAutoCompound(
           address candidate,
           uint8 value,
           uint256 candidateAutoCompoundingDelegationCount,
           uint256 delegatorDelegationCount
       ) external;
   
       /// @dev Fetch the total staked amount of a delegator, regardless of the
       /// candidate.
       /// @custom:selector e6861713
       /// @param delegator Address of the delegator.
       /// @return Total amount of stake.
       function getDelegatorTotalStaked(
           address delegator
       ) external view returns (uint256);
   
       /// @dev Fetch the total staked towards a candidate.
       /// @custom:selector bc5a1043
       /// @param candidate Address of the candidate.
       /// @return Total amount of stake.
       function getCandidateTotalCounted(
           address candidate
       ) external view returns (uint256);
   }
   

6. DelegationDAO.sol relies on a couple of standard OpenZeppelin contracts. Add the library with the following command:

   npm install @openzeppelin/contracts
   

Hardhat Configuration File¶

When setting up the hardhat.config.js file, we'll need to import a few plugins that we'll use throughout this guide. So to get started, we'll need the Hardhat Toolbox plugin, which conveniently bundles together Hardhat plugins that can be used to deploy and interact with contracts using Ethers, test contracts with Mocha and Chai, verify contracts with Etherscan, and more. You can run the following command to install the plugin:

npm install --save-dev @nomicfoundation/hardhat-toolbox 

If you're curious about additional Hardhat plugins, here is a complete list of official Hardhat plugins.

For the examples in this guide, you'll need to add your private keys for your two accounts on Moonbase Alpha. Since some of the testing will be done on a development node, you'll also need to add the private keys of two of the prefunded development node accounts, which for this example, we can use Alice and Bob. In addition, you'll add your Moonscan API key, which can be used for both Moonbase Alpha and Moonbeam.

Next you can take the following steps to modify the hardhat.config.js file and add Moonbase Alpha as a network:

1. Import plugins

2. Create a variable for your private key(s)

   Remember

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

3. Inside the module.exports, you need to provide the Solidity version

4. Add the Moonbase Alpha network configuration. You can modify the hardhat.config.js file to use any of the Moonbeam networks:

   MoonbeamMoonriverMoonbase AlphaMoonbeam Dev Node

   moonbeam: {
     url: 'INSERT_RPC_API_ENDPOINT', // Insert your RPC URL here
     chainId: 1284, // (hex: 0x504),
     accounts: [privateKey]
   },
   

   moonriver: {
     url: 'INSERT_RPC_API_ENDPOINT', // Insert your RPC URL here
     chainId: 1285, // (hex: 0x505),
     accounts: [privateKey]
   },
   

   moonbase: {
     url: 'https://rpc.api.moonbase.moonbeam.network',
     chainId: 1287, // (hex: 0x507),
     accounts: [privateKey]
   },
   

   dev: {
     url: 'http://127.0.0.1:9944',
     chainId: 1281, // (hex: 0x501),
     accounts: [privateKey]
   },
   

5. Add your Moonscan API key, which is required for the verification steps we'll be taking later in this tutorial

// 1. Import the Hardhat Toolbox plugin
require('@nomicfoundation/hardhat-toolbox');

// 2. Create variables for your private keys from your pre-funded Moonbase Alpha 
// testing accounts and your Moonscan API key
const privateKey = 'INSERT_PRIVATE_KEY';
const privateKey2 = 'INSERT_ANOTHER_PRIVATE_KEY';
const moonscanAPIKey = 'INSERT_MOONSCAN_API_KEY';

module.exports = {
  // 3. Specify the Solidity version
  solidity: '0.8.20',
  networks: {
    // 4. Add the Moonbase Alpha network specification
    moonbase: {
      url: 'https://rpc.api.moonbase.moonbeam.network',
      chainId: 1287, // 0x507 in hex
      accounts: [privateKey, privateKey2]
    },
    dev: {
      url: 'http://127.0.0.1:9944',
      chainId: 1281, // 0x501 in hex
      accounts: [
        '0x5fb92d6e98884f76de468fa3f6278f8807c48bebc13595d45af5bdc4da702133', // Alice's PK
        '0x8075991ce870b93a8870eca0c0f91913d12f47948ca0fd25b49c6fa7cdbeee8b' // Bob's PK
      ]
    },
    moonbeam: {
      url: 'https://rpc.api.moonbeam.network', // Or insert your own RPC URL here
      chainId: 1284, // 0x504 in hex
      accounts: [privateKey, privateKey2]
    },
  },
  // 5. Set up your Moonscan API key for contract verification
  // Moonbeam and Moonbase Alpha Moonscan use the same API key
  etherscan: {
    apiKey: {
      moonbaseAlpha: moonscanAPIKey, // Moonbase Moonscan API Key
      moonbeam: moonscanAPIKey, // Moonbeam Moonscan API Key    
    }
  }
};

You're now ready to move on to compilation and testing.

Compiling the Contract¶

To compile the contract you can simply run:

npx hardhat compile

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

Testing¶

A robust smart contract development workflow is incomplete without a testing suite. Hardhat has a number of tools that make it easy to write and run tests. In this section, you'll learn the basics of testing your smart contracts and some more advanced techniques.

Hardhat tests are typically written with Mocha and Chai. Mocha is a JavaScript testing framework and Chai is a BDD/TDD JavaScript assertion library. BDD/TDD stands for behavior and test driven development respectively. Effective BDD/TDD necessitates writing your tests before writing your smart contract code. The structure of this tutorial doesn't strictly follow these guidelines, but you may wish to adopt these principles in your development workflow. Hardhat recommends using Hardhat Toolbox, a plugin that bundles everything you need to get started with Hardhat, including Mocha and Chai.

Because we will initially be running our tests on a local Moonbeam node, we need to specify Alice's address as the address of our target collator (Alice's account is the only collator for a local development node):

0xf24FF3a9CF04c71Dbc94D0b566f7A27B94566cac

If instead you prefer to run your tests against Moonbase Alpha, you can choose the below collator, or any other collator on Moonbase Alpha you would like the DAO to delegate to:

0x4c5A56ed5A4FF7B09aA86560AfD7d383F4831Cce

Configuring the Test File¶

To set up your test file, take the following steps:

1. Create a tests directory

   mkdir tests
   

2. Create a new file called Dao.js

   touch tests/Dao.js
   

3. Then copy and paste the contents below to set up the initial structure of your test file. Be sure to read the comments as they can clarify the purpose of each line

   // Import Ethers
   const { ethers } = require('hardhat');
   
   // Import Chai to use its assertion functions here
   const { expect } = require('chai');
   
   // Indicate Alice's address as the target collator on local development node
   const targetCollator = '0xf24FF3a9CF04c71Dbc94D0b566f7A27B94566cac';
   

Deploying a Staking DAO for Testing¶

Before we can run any test cases we'll need to launch a staking DAO with an initial configuration. Our setup here is relatively simple - we'll be deploying a staking DAO with a single administrator (the deployer) and then adding a new member to the DAO. This simple setup is perfect for demonstration purposes, but it's easy to imagine more complex configurations you'd like to test, such as a scenario with 100 DAO members or one with multiple admins of the DAO.

Mocha's describe function enables you to organize your tests. Multiple describe functions can be nested together. It's entirely optional but can be useful especially in complex projects with a large number of test cases. You can read more about constructing tests and getting started with Mocha on the Mocha docs site.

We'll define a function called deployDao that will contain the setup steps for our staking DAO. To configure your test file, add the following snippet:

// The describe function receives the name of a section of your test suite, and a
// callback. The callback must define the tests of that section. This callback
// can't be an async function
describe('Dao contract', function () {
  async function deployDao() {
    // Get the contract factory and signers here
    const [deployer, member1] = await ethers.getSigners();
    const delegationDao = await ethers.getContractFactory('DelegationDAO');

    // Deploy the staking DAO and wait for the deployment transaction to be confirmed
    const deployedDao = await delegationDao.deploy(targetCollator, deployer.address);
    await deployedDao.waitForDeployment();

    // Return the deployed DAO and the first member of the DAO to allow the tests to 
    // access and interact with them
    return { deployedDao, member1 };
  }

  // The test cases should be added here
});

Writing your First Test Cases¶

First, you'll create a subsection called Deployment to keep the test file organized. This will be nested within the Dao contract describe function. Next you'll define your first test case by using the it Mocha function. This first test is simply checking to see that the staking DAO is correctly storing the address of the target collator.

Go ahead and add the below snippet to the end of your Dao contract function.

// You can nest calls to create subsections
describe('Deployment', function () {
  // Mocha's it function is used to define each of your tests.
  // It receives the test name, and a callback function.
  // If the callback function is async, Mocha will await it
  it('should store the correct target collator in the DAO', async function () {

    // Set up our test environment by calling deployDao
    const { deployedDao } = await deployDao();

    // The expect function receives a value and wraps it in an assertion object.
    // This test will pass if the DAO stored the correct target collator
    expect(await deployedDao.targetCollator()).to.equal(targetCollator);
  });

  // The following test cases should be added here
});

Now, add another test case. When a staking DAO is launched, it shouldn't have any funds. This test verifies that is indeed the case. Go ahead and add the following test case to your Dao.js file:

it('should initially have 0 funds in the DAO', async function () {
  const { deployedDao } = await deployDao();

  // This test will pass if the DAO has no funds as expected before any contributions
  expect(await deployedDao.totalStake()).to.equal(0);
});

Function Reverts¶

Now, you'll implement a more complex test case with a slightly different architecture. In prior examples, you've verified that a function returns an expected value. In this one, you'll be verifying that a function reverts. You'll also change the address of the caller to test an admin-only function.

In the staking DAO contract, only admins are authorized to add new members to the DAO. One could write a test that checks to see if the admin is authorized to add new members but perhaps a more important test is to ensure that non-admins can't add new members. To run this test case under a different account, you're going to ask for another address when you call ethers.getSigners() and specify the caller in the assertion with connect(member1). Finally, after the function call you'll append .to.be.reverted to indicate that the test case is successful if the function reverts. And if it doesn't revert it's a failed test!

it('should not allow non-admins to grant membership', async function () {
  const { deployedDao, member1 } = await deployDao();

  // We use connect to call grant_member from member1's account instead of admin.
  // This test will succeed if the function call reverts and fails if the call succeeds
  await expect(
    deployedDao
      .connect(member1)
      .grant_member('0x0000000000000000000000000000000000000000')
  ).to.be.reverted;
});

Signing Transactions from Other Accounts¶

For this example, you'll check to verify whether the newly added DAO member can call the check_free_balance() function of staking DAO, which has an access modifier such that only members can access it.

it('should only allow members to access member-only functions', async function () {
  const { deployedDao, member1 } = await deployDao();

  // Add a new member to the DAO
  const transaction = await deployedDao.grant_member(member1.address);
  await transaction.wait();

  // This test will succeed if the DAO member can call the member-only function.
  // We use connect here to call the function from the account of the new member
  expect(await deployedDao.connect(member1).check_free_balance()).to.equal(0);
});

And that's it! You're now ready to run your tests!

Running your Tests¶

If you've followed all of the prior sections, your Dao.js test file should be all set to go.

// Import Ethers
const { ethers } = require('hardhat');
// Import Chai to use its assertion functions here
const { expect } = require('chai');

// Indicate the collator the DAO wants to delegate to
const targetCollator = '0x4c5A56ed5A4FF7B09aA86560AfD7d383F4831Cce';

// The describe function receives the name of a section of your test suite, and a
// callback. The callback must define the tests of that section. This callback
// can't be an async function
describe('Dao contract', function () {
  async function deployDao() {
    // Get the contract factory and signers here
    const [deployer, member1] = await ethers.getSigners();
    const delegationDao = await ethers.getContractFactory('DelegationDAO');

    // Deploy the staking DAO and wait for the deployment transaction to be confirmed
    const deployedDao = await delegationDao.deploy(
      targetCollator,
      deployer.address
    );
    await deployedDao.waitForDeployment();

    // Return the deployed DAO and the first member of the DAO to allow the tests to 
    // access and interact with them
    return { deployedDao, member1 };
  }

  // You can nest calls to create subsections
  describe('Deployment', function () {
    // Mocha's it function is used to define each of your tests.
    // It receives the test name, and a callback function
    //
    // If the callback function is async, Mocha will await it
    it('should store the correct target collator in the DAO', async function () {
      // Set up our test environment by calling deployDao
      const { deployedDao } = await deployDao();

      // The expect function receives a value and wraps it in an assertion object.
      // This test will pass if the DAO stored the correct target collator
      expect(await deployedDao.target()).to.equal(targetCollator);
    });

    // The following test cases should be added here
    it('should initially have 0 funds in the DAO', async function () {
      const { deployedDao } = await deployDao();

      // This test will pass if the DAO has no funds as expected before any contributions
      expect(await deployedDao.totalStake()).to.equal(0);
    });

    it('should not allow non-admins to grant membership', async function () {
      const { deployedDao, member1 } = await deployDao();

      // We use connect to call grant_member from member1's account instead of admin.
      // This test will succeed if the function call reverts and fails if the call succeeds
      await expect(
        deployedDao
          .connect(member1)
          .grant_member('0x0000000000000000000000000000000000000000')
      ).to.be.reverted;
    });

    it('should only allow members to access member-only functions', async function () {
      const { deployedDao, member1 } = await deployDao();

      // Add a new member to the DAO
      const transaction = await deployedDao.grant_member(member1.address);
      await transaction.wait();

      // This test will succeed if the DAO member can call the member-only function.
      // We use connect here to call the function from the account of the new member
      expect(await deployedDao.connect(member1).check_free_balance()).to.equal(
        0
      );
    });
  });
});

Since our test cases encompass mostly configuration and setup of the staking DAO and don't involve actual delegation actions, we'll be running our tests on a Moonbeam development node (local node). Remember that Alice (0xf24FF3a9CF04c71Dbc94D0b566f7A27B94566cac) is the only collator on a local development node. You can use the flag --network moonbase to run the tests using Moonbase Alpha. In that case, be sure that your deployer address is sufficiently funded with DEV tokens.

First, make sure that your local Moonbeam node is running by following the instructions for launching a local development node. Take precautions because you could inadvertently send real funds to the Alice and Bob development accounts, which would result in a loss of those funds.

You can run your tests with the following command:

npx hardhat test --network dev tests/Dao.js

If everything was set up correctly, you should see output like the following:

Deploying to Moonbase Alpha¶

In the following steps, we'll be deploying the DelegationDAO to the Moonbase Alpha TestNet. Before deploying to Moonbase Alpha or Moonbeam, double check you're not using the Alice and Bob accounts, which should only be used on a local development node.

As a side note, DelegationDAO relies on StakingInterface.sol, which is a Substrate-based offering unique to Moonbeam networks. The Hardhat Network and forked networks are simulated EVM environments which do not include the Substrate-based precompiles like StakingInterface.sol. Therefore, DelegationDAO will not work properly if deployed to the local default Hardhat Network or a forked network.

To deploy DelegationDAO.sol, you can write a simple script. You can create a new directory for the script and name it scripts:

mkdir scripts

Then add a new file to it called deploy.js:

touch scripts/deploy.js

Next, you need to write your deployment script which can be done using ethers. Because you'll be running it with Hardhat, you don't need to import any libraries.

To get started, take the following steps:

1. Specify the address of the active collator the DAO intends to delegate to. In this case, we've specified the address of the PS-1 Collator (note: this is different from the address of the Alice collator on a local development node)
2. Specify the deployer address as the admin of the DAO. It's important that the deployer be the admin of the DAO to ensure later tests work as expected
3. Create a local instance of the contract with the getContractFactory method
4. Use the deploy method that exists within this instance to instantiate the smart contract
5. Once deployed, you can fetch the address of the contract using the contract instance

When all is said and done your deployment script should look similar to the following:

// 1. The PS-1 collator on Moonbase Alpha is chosen as the DAO's target
const targetCollator = '0x4c5A56ed5A4FF7B09aA86560AfD7d383F4831Cce';

async function main() {
  // 2. Get the address of the deployer to later be set as the admin of the DAO
  const [deployer] = await ethers.getSigners();
  console.log('Deploying contracts with the account:', deployer.address);

  // 3. Get an instance of DelegationDAO
  const delegationDao = await ethers.getContractFactory('DelegationDAO');

  // 4. Deploy the contract specifying two params: the desired collator to
  // delegate to and the address of the deployer (the initial DAO admin)
  const deployedDao = await delegationDao.deploy(
    targetCollator,
    deployer.address
  );
  await deployedDao.waitForDeployment();

  // 5. Print out the address of the deployed staking DAO contract
  console.log('DAO address:', deployedDao.target);
}

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

Make sure you've funded your accounts with Moonbase Alpha DEV tokens. You can now deploy DelegationDAO.sol using the run command and specifying moonbase as the network (as configured in the hardhat.config.js file):

npx hardhat run --network moonbase scripts/deploy.js

After a few seconds, the contract is deployed, and you should see the address in the terminal.

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

Verifying Contracts on Moonbase Alpha¶

Contract verification is an essential step of any developer's workflow, particularly in the theoretical example of this staking DAO. Potential participants in the DAO need to be assured that the smart contract works as intended - and verifying the contract allows anyone to observe and analyze the deployed smart contract.

While it's possible to verify smart contracts on the Moonscan website, the Hardhat Etherscan plugin enables us to verify our staking DAO in a faster and easier manner. It's not an exaggeration to say that the plugin dramatically simplifies the contract verification process, especially for projects that include multiple Solidity files or libraries.

Before beginning the contract verification process, you'll need to acquire a Moonscan API Key. Note that Moonbeam and Moonbase Alpha use the same Moonbeam Moonscan API key, whereas you'll need a distinct API key for Moonriver.

To verify the contract, you will run the verify command and pass in the network where the DelegationDao contract is deployed, the address of the contract, and the two constructor arguments that you specified in your deploy.js file, namely, the address of the target collator and the address you deployed the smart contract with (sourced from the hardhat.config.js file).

npx hardhat verify --network moonbase INSERT_CONTRACT_ADDRESS 0x4c5A56ed5A4FF7B09aA86560AfD7d383F4831Cce INSERT_DEPLOYER_ADDRESS

In your terminal you should see the source code for your contract was successfully submitted for verification. If the verification was successful, you should see Successfully verified contract and there will be a link to the contract code on Moonscan for Moonbase Alpha. If the plugin returns an error, double check that your API key is configured correctly and that you have specified all necessary parameters in the verification command. You can refer to the guide to the Hardhat Etherscan plugin for more information.

Deploying to Production on Moonbeam Mainnet¶

In the following steps, we'll be deploying the DelegationDAO contract to the Moonbeam MainNet network. Remember to add the Moonbeam network to your hardhat.config.js and update the private keys of your accounts on Moonbeam if you haven't done so already. Before deploying DelegationDAO to Moonbeam, we need to change the address of the target collator, since our target collator on Moonbase Alpha does not exist on Moonbeam. Head to your deploy script and change the target collator to 0x1C86E56007FCBF759348dcF0479596a9857Ba105 or another Moonbeam collator of your choice. Your deploy.js script should thus look like the following:

// 1. The moonbeam-foundation-03 collator on Moonbeam is chosen as the DAO's target
const targetCollator = '0x1C86E56007FCBF759348dcF0479596a9857Ba105';

async function main() {
  // 2. Get the address of the deployer to later be set as the admin of the DAO
  const [deployer] = await ethers.getSigners();
  console.log('Deploying contracts with the account:', deployer.address);

  // 3. Get an instance of DelegationDAO
  const delegationDao = await ethers.getContractFactory('DelegationDAO');

  // 4. Deploy the contract specifying two params: the desired collator to delegate
  // to and the address of the deployer (synonymous with initial DAO admin)
  const deployedDao = await delegationDao.deploy(
    targetCollator,
    deployer.address
  );
  await deployedDao.waitForDeployment();

  console.log('DAO address:', deployedDao.target);
}

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

You can now deploy DelegationDAO.sol using the run command and specifying moonbeam as the network:

npx hardhat run --network moonbeam scripts/deploy.js

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

After a few seconds, the contract is deployed, and you should see the address in the terminal.

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

Verifying Contracts on Moonbeam¶

In this section, we'll be verifying the contract that was just deployed on Moonbeam. Before beginning the contract verification process, you'll need to acquire a Moonscan API Key. Note that Moonbeam and Moonbase Alpha use the same Moonbeam Moonscan API key, whereas you'll need a distinct API key for Moonriver.

To verify the contract, you will run the verify command and pass in the network where the DelegationDao contract is deployed, the address of the contract, and the two constructor arguments that you specified in your deploy.js file, namely, the address of the target collator and the address you deployed the smart contract with (sourced from your hardhat.config.js file). Remember that the target collator of the staking DAO on Moonbeam is different from the target collator of the staking DAO on Moonbase Alpha.

npx hardhat verify --network moonbeam INSERT_CONTRACT_ADDRESS 0x1C86E56007FCBF759348dcF0479596a9857Ba105 INSERT_DEPLOYER_ADDRESS

In your terminal you should see the source code for your contract was successfully submitted for verification. If the verification was successful, you should see Successfully verified contract and there will be a link to the contract code on Moonbeam Moonscan. If the plugin returns an error, double check that your API key is configured correctly and that you have specified all necessary parameters in the verification command. You can refer to the guide to the Hardhat Etherscan plugin for more information.

And that's it! We covered a lot of ground in this tutorial but there's more resources available if you'd like to go deeper, including the following:

• Hardhat guide to Testing Contracts
• Writing tasks and scripts