████████ ██    ██ ███████ ███████ ████████  ██████  ██   ██ ███████ ███    ██ 
   ██    ██    ██ ██      ██         ██    ██    ██ ██  ██  ██      ████   ██ 
   ██    ██    ██ █████   █████      ██    ██    ██ █████   █████   ██ ██  ██ 
   ██    ██    ██ ██      ██         ██    ██    ██ ██  ██  ██      ██  ██ ██ 
   ██     ██████  ██      ██         ██     ██████  ██   ██ ███████ ██   ████ 

TuffToken

Getting Started

First install all dependencies with:

npm install

Next, copy the .env-template to a .env file. Fill out the variables, you can reach out to a team member to acquire any shared secrets.

Now you are ready to start running some commands. ./package.json contains helpful aliases, but here are a few common commands:

npm run test
npm run test test/aaveLPManager.ts
npm run compile

npx hardhat accounts
npx hardhat node

Contract Development

Be aware of the purposeful directory structure within ./contract. With hardhat, we can compile contracts with n number of versions, but contracts compiled on two different versions cannot directly call each other. We came up with the following directory structure to ensure development is quick and easy, and the code stays safe.

Everything that is using the latest solidity version that this repo supports lives in the root of ./contract/. If a contract uses a lower solidity version then it will live in the respective version folder. For example, a contract that requires solidity 0.6.12 then it belongs in./contract/v6/. Thus, anything that is in a ./contract/v* sub folder must be called via abi. This should help make it clear which contracts you can import directly, and thus easier and safer to use, vs which you must call via abi.

Diamond Contracts

We decided to structure our contracts with the diamond standard to ensure we write clean and concise code, while still practicing separation-of-concerns. Among other benefits, the diamond standard also enabled us to treat our code as one meta-contract which shares the same owner, address, and wallet. Architecting our contract this way also means transactions will use less gas as they do not have to transfer tokens from each contract's wallet.

It is encouraged to familiarize yourself with Diamonds, this repo is a good place to start. Note that we chose the 3rd implementation here.

It is imperative that you understand how state and storage is managed within Diamonds. This link goes over several options and their pros and cons. This project uses the diamond storage method, which you can learn more about here and here. There are a few additional quirks I would like to call out:

• There are some key differences with inline assembly between solidity version
• All first-party contract function names must be unique. This means no interfaces
• The key feature to support diamond storage was released in solidity v0.6.4. Thus, all contracts must compile with versions higher than that
• You can mix and match different storage solutions, but that should only be a last resort. It is untested

Tenderly

Tenderly is useful to help debug txs and state changes more in depth than local debugging. You can set up Tenderly per .env.template and running npm run test:tenderly. Here are a few observations I have made:

• Automating tenderly forks at hardhat runtime is not possible. I have tried many times and in many different ways. To work around this you must manually create the fork through their web app or through cli. Once created, update your .env file with the new rpc URL
• If/when you receive an error, you will likely find a misleading error in your terminal. I often find code=UNPREDICTABLE_GAS_LIMIT errors. If this occurs, take the tx output and manually "simulate" the tx in tenderly. Doing so will provide the real error and additional debugging tools to determine your issue.

Back Testing

In a similar fashion to testing, we fork mainnet to a local hardhat network. This lets us imitate mainnet and explore various scenarios given our contracts. To do this, the local network is forked at a specific block, then we deploy our contracts, and finally we apply the txs found in subsequent blocks. This will model how our contract will behave given the changes occurred in the mainnet enviroment.

Before we can start modeling, we need the "future" tx data that we will be replaying for the local network. We have created a convenient download and serializer hardhat task to handle this for you. It requires two parameters where you specify the range of blocks you want to fetch. Note that the values cannot exceed the blockNumber configured in hardhat.config.ts, as hardhat relies on that forked, archival block data to create the local network; from which we fetch that tx data from.

# Block number at 01/01/2021 00:00 GMT
export START_BLOCK_NUM=11565019
export START_BLOCK_NUM=13302360

# Block number at 01/01/2022 00:00 GMT
export END_BLOCK_NUM=13916166
export END_BLOCK_NUM=13302372

npm run download_block_data -- --start-block-number ${START_BLOCK_NUM} --end-block-number ${END_BLOCK_NUM}

pip3 install ethereum-etl

ethereumetl export_blocks_and_transactions --start-block ${START_BLOCK_NUM} --end-block ${END_BLOCK_NUM} --provider-uri https://mainnet.infura.io/v3/0feb75e50f9a4dc2ae2d4333d4707333 --transactions-output ./block_data/transactions.csv

With the block txs downloaded, we must now configure hardhat's network to start at the appropriate block. Using the example from above, we would update the blockNumber configured in hardhat.config.ts to 13302359 (one less than the start block number). We do this because then we will deploy the contract, and then apply the txs we just fetched.

Deploying

Pre-Deploy Checks

1. Ensure TUFF_STARTING_PRICE is set to the correct value based on the current blocks ETH price
2. Review and source your .env file. Enusre all wallets have the correct private key
3. Run npm run node to deploy a local version of the contracts based on the current mainnet block
4. Review logs from step above
5. Run npm run deploy_kovan to deploy the contracts to kovan
6. Review logs from step above

Deploy to mainnet

1. Ensure wallets have sufficient ETH to pay for gas. Check the latest main GitHub actions to get estimated contract deployment gas cost
2. Run npm run deploy_mainnet to deploy the contracts to mainnet
3. Review logs from step above

Post-Deploy

1. Commit deployment logs to main branch
2. Review addresses on etherscan and dApp

License

Full License. All source code files need to start with a comment containing SPDX-License-Identifier: agpl-3.0.