RECY Network smart contract

This project is bootstrapped with Hardhat, a development environment for Ethereum smart contracts.

Development

1. Install dependencies

   yarn

2. Compile contracts

   yarn compile

3. Test contracts

   yarn test

Deploy

1. Contracts can be deployed on any EVM network. To deploy contracts, you need to set up a .env file with the following variables

   HARDHAT_PRIVATE_KEY=0x...

2. Deploy contracts

Note

Currently arguments for deployment are hardcoded in the scripts. You can change them in the scripts before deploying.

Script	Description	Arguments
deploy-all	Deploy all contracts
deploy-crecy	Deploy CRECY ERC20 contract	totalSupply, initialSupply
deploy-fcw	Deploy FCW ERC721 contract
deploy-timelock	Deploy timelock contract	crecy address

Network	Description
localhost	Hardhat localnet
celo	CELO mainnet
alfajores	CELO testnet

yarn hardhat run scripts/<script>.ts --network <network>

Verify smart contract codes on explorer

yarn hardhat verify --network <network> <address>

Deployed Addresses

Contract Name	Network	Address
cRECY	Celo	0x34C11A932853Ae24E845Ad4B633E3cEf91afE583
DeTrashCertificate	Polygon	0xbc68c4ec4182e1d2c73b5e58bd92be9871db2230
TimeLock	Celo	0x2B7D8711E26E78218791B85EdB1ff4EFf1A8BF54
RecyCertificate	Celo	0xd574e0605c20Fc683feDBDD01ce745fF2C1a6f40

Testnet

Contract Name	Address
CRecy	0x004c368A3fb45b0CD601e2203Fd2948D9d695a3b
FCWStatus	0xbf10E8d903bB4fcc705740d37d5668e2d5A6CBbC
RecyCertificate	0x56A396a452f4F44412f089Efc3c4bF27aE6B5423
TimeLock (deprecated)	0x64604b6564862d4544583943A108d948916CD2ec

TimeLock Guide

This document describes how to interact with the Lock Contract in the cRecy ecosystem. This implementation considers the existence of the following contracts:

• TimeLock: the contract responsible for keeping tokens during lock period and for emitting NFT certificates.
• CRecy: the ERC-20 CRecy token
• RecyCertificate: the NFT for each certificate
• FCWStatus: the Friends of the Clean World contract

The CRecy and RecyCertificate addresses are passed as parameters during the TimeLock initialization. It supports the following roles:

• ADMIN_ROLE
• OPERATOR_ROLE
• PAUSER_ROLE

The current version of the contract is published on Celo Network in the following address: 0x2B7D8711E26E78218791B85EdB1ff4EFf1A8BF54.

Certificate Creation

Every certificate submitted to the Lock Contract needs to be signed according to the EIP-712. Each certificate should be an object with the following data and types:

CertificateAuthorization: [
          { name: "institution", type: "bytes32" },
          { name: "tons", type: "uint8" },
          { name: "baseYear", type: "uint16" },
          { name: "baseMonth", type: "uint8" },
          { name: "timespan", type: "uint8" },
          { name: "signer", type: "address" },
          { name: "authorization", type: "bytes32" },
          { name: "deadline", type: "uint256" },
]

The first 5 fields are related to the certificate itself, while the last 3 are used to validate the signature on-chain, as follows:

• signer: address of the account that will sign the certificate. Should have ADMIN_ROLE or OPERATOR_ROLE in the Lock Contract
• authorization: a unique control number in hex format for each authorization
• deadline: the date until that certificate can be presented to the Lock Contract

Signing Process

Each signature should also contain the message, the CertificateAuthorization types object, and the following domain:

{
      chainId: 31337,
      name: "GenericTypedMessage",
      version: "1",
      verifyingContract: "0x2B7D8711E26E78218791B85EdB1ff4EFf1A8BF54"
 }

The signature process requires an account with ADMIN_ROLE or OPERATOR_ROLE to generate the signed message. It can be accomplished via a script or via a DApp, where signers can connect their EOA using solutions such as Metamask, Wallet Connect or any other equivalent solution.

Here, we provide an example using Ethers.js with a randomly created account:

import moment from "moment";
import { HDNodeWallet } from "@ethersproject/wallet"
import { fromRpcSig } from 'ethereumjs-util';
import { doLock } from "./lockUtils.js"

certTypedMessage = {
   domain: {
     chainId: 31337,
     name: "GenericTypedMessage",
     version: "1",
     verifyingContract: "0x2B7D8711E26E78218791B85EdB1ff4EFf1A8BF54"
   },
   message: {
     institution: ethers.encodeBytes32String("Acme Inc."),
     tons: '3',
     baseYear: '2024',
     baseMonth: '1',
     timespan: '12',
     signer: admin.address,
     authorization: `0x1`,
     deadline: moment().add(1, 'day').format('X')
   },
   types: {
     CertificateAuthorization: [
       { name: "institution", type: "bytes32" },
       { name: "tons", type: "uint8" },
       { name: "baseYear", type: "uint16" },
       { name: "baseMonth", type: "uint8" },
       { name: "timespan", type: "uint8" },
       { name: "signer", type: "address" },
       { name: "authorization", type: "bytes32" },
       { name: "deadline", type: "uint256" },
     ],
   },
 };
 const wallet = HDNodeWallet.createRandom();
 const amount = 100; // A value to be defined
 wallet.signTypedData(
     certTypedMessage.domain,
     certTypedMessage.types,
     certTypedMessage.message
 ).then( async (signedCertificate) => {
     const rsvSignedCertificate = fromRpcSig(signedCertificate);
     await doLock(amount, certTypedMessage.message, rsvSignedCertificate);
 });

Locking a certificate

To lock a certificate in the Lock Contract, it is necessary to meet the following conditions:

• Having a signed, not used, not expired, certificate { r, s, v} components
• Approval from certificate receiving account for the Lock Contract to move at least the amount of CRecy tokens to be locked on their behalf

Any account can call a lock procedure in the Lock Contract passing the lock amount, the certificate data and the signature. Ahead, we provide the lockUtils.js script that exports a function to lock an amount in CRecy and a certificate in the contract.

import { Contract } from  "@ethersproject/contract";
import lockContractAbi from "./lockContractAbi.json";

export const doLock (amount, certificate, signature) => {
	const contract = new Contract("0x2B7D8711E26E78218791B85EdB1ff4EFf1A8BF54", lockContractAbi);

	contract.lock(amount, certificate, signature);
}