Using Truffle

Overview

Truffle is a popular development framework for building, testing, and deploying smart contracts on the Waterfall network. It provides a suite of tools and libraries that make it easier for developers to write, compile, and deploy smart contracts, as well as to interact with the Waterfall network.

Some of the key features of Truffle include:

A development environment that includes a console for interacting with the Waterfall network
A compiler that can convert Solidity code (the language used to write smart contracts on Waterfall) into bytecode that can be executed on the Ethereum Virtual Machine (EVM)
A test framework that allows developers to write automated tests for their smart contracts
A deployment tool that makes it easy to deploy smart contracts to the Waterfall network
A built-in smart contract management system that makes it easy to keep track of and manage multiple contracts

Truffle has become a popular tool among Waterfall developers because it simplifies the development process and makes it easier to write, test, and deploy smart contracts. It also provides a wide range of resources and documentation to help developers get started, and to learn more about smart contract development on the Waterfall network.

Installation

Refer to the installation instructions to install Truffle.
eg: npm install -g truffle

Create Project

Create a new directory for your Truffle project:
```
mkdir HelloWaterfall
cd HelloWaterfall
```
Create Truffle project
```
truffle init
```

Create HelloWaterfall.sol file in contracts directory and paste example contract from solidity documentation site

// SPDX-License-Identifier: GPL-3.0
pragma solidity ^0.8.4;

contract Coin {
    // The keyword "public" makes variables
    // accessible from other contracts
    address public minter;
    mapping(address => uint) public balances;

    // Events allow clients to react to specific
    // contract changes you declare
    event Sent(address from, address to, uint amount);

    // Constructor code is only run when the contract
    // is created
    constructor() {
        minter = msg.sender;
    }

    // Sends an amount of newly created coins to an address
    // Can only be called by the contract creator
    function mint(address receiver, uint amount) public {
        require(msg.sender == minter);
        balances[receiver] += amount;
    }

    // Errors allow you to provide information about
    // why an operation failed. They are returned
    // to the caller of the function.
    error InsufficientBalance(uint requested, uint available);

    // Sends an amount of existing coins
    // from any caller to an address
    function send(address receiver, uint amount) public {
        if (amount > balances[msg.sender])
            revert InsufficientBalance({
                requested: amount,
                available: balances[msg.sender]
            });

        balances[msg.sender] -= amount;
        balances[receiver] += amount;
        emit Sent(msg.sender, receiver, amount);
    }
}

Compile and migration

Compile contracts
```
truffle compile
```

Create 1-deploy.js file in migrations directory and past next code:

const Coin = artifacts.require("Coin");

module.exports = function (deployer) {
    deployer.deploy(Coin);
};

Check contracts in develop mode

Go to the develop console

truffle develop

1. Deploy contract

migrate

let instance = await Coin.deployed();

2. Check minter

> instance.minter()
'0xF0fE891F97376AB4233C27ae8E2F13f51Fa116F2'

3. Check balance

> let balance = await instance.balances('0xF0fE891F97376AB4233C27ae8E2F13f51Fa116F2')
undefined
> balance.toNumber()
0

4. Mint token

> instance.mint('0xF0fE891F97376AB4233C27ae8E2F13f51Fa116F2', 1000)
{
  tx: '0x5cf95ddb38ce1a148ce61c46f51f599b7e8929ad479c0a948cf6e8e74b4cfec5',
  receipt: {
   transactionHash: '0x5cf95ddb38ce1a148ce61c46f51f599b7e8929ad479c0a948cf6e8e74b4cfec5',
   transactionIndex: 0,
   blockNumber: 2,
   blockHash: '0xf05268bdd02a1e5a9cf200f3fcf7c614703ceedf95403117581b7ccd5053ce12',
   from: '0xf0fe891f97376ab4233c27ae8e2f13f51fa116f2',
   to: '0x90c43cee404a473304ff3a0d5b52040516731e80',
   cumulativeGasUsed: 46806,
   gasUsed: 46806,
   contractAddress: null,
   logs: [],
   logsBloom: '0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000',
   status: true,
   effectiveGasPrice: 3278849404,
   type: '0x2',
   rawLogs: []
  },
  logs: []
}

5. Check balance

> balance = await instance.balances('0xF0fE891F97376AB4233C27ae8E2F13f51Fa116F2')
BN {
  negative: 0,
  words: [ 1000, <1 empty item> ],
  length: 1,
  red: null
}
> balance.toNumber()
1000

Deploy to Waterfall Network

Install packages
```
npm install @truffle/hdwallet-provider
```
If you're having trouble installing, you can fix it npm config set legacy-peer-deps true
Uncomment const HDWalletProvider = require('@truffle/hdwallet-provider'); line
Go to Networks - RPC Endpoints page and check params

Add Waterfall Network to truffle-config.js file

networks: {
  waterfall: {
   from: 'a7062A2Bd7270740f1d15ab70B3Dee189A87b6DE', // Your Deployer Account
   provider: () => new HDWalletProvider({
     privateKeys: ['07201008f00b31de405a0af22ff04871044e027878929b7b47569ca76555ff09'], // Private key from your account
     providerOrUrl: `wss://rpc.testnet9.waterfall.network/ws`
   }),
   network_id: 1501869,
   confirmations: 5,
   websocket: true,
   skipDryRun: true,
  }
}

Deploy contract
```
truffle migrate --network waterfall
```