Badger Strategy V1 Brownie Mix

• Video Introduction: https://youtu.be/FVbhgPYW_D0

• Example Project: https://github.com/Badger-Finance/wBTC-AAVE-Rewards-Farm-Badger-V1-Strategy

• Full Project Walkthrough: https://www.youtube.com/watch?v=lTb0RFJJx2k

• 1-1 Mentoring (Valid throughout HackMoney and Gitcoin Round 10): https://calendly.com/alex-entreprenerd/badger-hackmoney-1-1

What you'll find here

• Basic Solidity Smart Contract for creating your own Badger Strategy (contracts/MyStrategy.sol)

• Interfaces for some of the most used DeFi protocols on ethereum mainnet. (interfaces)

• Dependencies for OpenZeppelin and other libraries. (deps)

• Sample test suite that runs on mainnet fork. (tests)

This mix is configured for use with Ganache on a forked mainnet.

Installation and Setup

1. Use this code by clicking on Use This Template

2. Download the code with git clone URL_FROM_GITHUB

3. Install Brownie & Ganache-CLI, if you haven't already.

4. Copy the .env.example file, and rename it to .env

5. Sign up for Infura and generate an API key. Store it in the WEB3_INFURA_PROJECT_ID environment variable.

6. Sign up for Etherscan and generate an API key. This is required for fetching source codes of the mainnet contracts we will be interacting with. Store the API key in the ETHERSCAN_TOKEN environment variable.

7. Install the dependencies in the package

## Javascript dependencies
npm i

## Python Dependencies
pip install virtualenv
virtualenv venv
source venv/bin/activate
pip install -r requirements.txt

Basic Use

To deploy the demo Badger Strategy in a development environment:

1. Open the Brownie console. This automatically launches Ganache on a forked mainnet.

  brownie console

2. Run Scripts for Deployment

  brownie run deploy

Deployment will set up a Vault, Controller and deploy your strategy

3. Run the test deployment in the console and interact with it

  brownie console
  deployed = run("deploy")

  ## Takes a minute or so
  Transaction sent: 0xa0009814d5bcd05130ad0a07a894a1add8aa3967658296303ea1f8eceac374a9
  Gas price: 0.0 gwei   Gas limit: 12000000   Nonce: 9
  UniswapV2Router02.swapExactETHForTokens confirmed - Block: 12614073   Gas used: 88626 (0.74%)

  ## Now you can interact with the contracts via the console
  >>> deployed
  {
      'controller': 0x602C71e4DAC47a042Ee7f46E0aee17F94A3bA0B6,
      'deployer': 0x66aB6D9362d4F35596279692F0251Db635165871,
      'lpComponent': 0x028171bCA77440897B824Ca71D1c56caC55b68A3,
      'rewardToken': 0x7Fc66500c84A76Ad7e9c93437bFc5Ac33E2DDaE9,
      'sett': 0x6951b5Bd815043E3F842c1b026b0Fa888Cc2DD85,
      'strategy': 0x9E4c14403d7d9A8A782044E86a93CAE09D7B2ac9,
      'vault': 0x6951b5Bd815043E3F842c1b026b0Fa888Cc2DD85,
      'want': 0x6B175474E89094C44Da98b954EedeAC495271d0F
  }
  >>>

  ## Deploy also uniswaps want to the deployer (accounts[0]), so you have funds to play with!
  >>> deployed.want.balanceOf(a[0])
  240545908911436022026

Adding Configuration

To ship a valid strategy, that will be evaluated to deploy on mainnet, with potentially $100M + in TVL, you need to:

1. Add custom config in /config/__init__.py
2. Write the Strategy Code in MyStrategy.sol
3. Customize the StrategyResolver in /config/StrategyResolver.py so that snapshot testing can verify that operations happened correctly
4. Write any extra test to confirm that the strategy is working properly

Add a custom want configuration

Most strategies have a:

• want the token you want to increase the balance of
• lpComponent the token representing how much you deposited in the yield source
• reward the token you are farming, that you'll swap into want

Set these up in /config/__init__.py this mix will automatically be set up for testing and deploying after you do so

Implementing Strategy Logic

contracts/MyStrategy.sol is where you implement your own logic for your strategy. In particular:

• Customize the initialize Method
• Set a name in MyStrategy.getName()
• Set a version in MyStrategy.version()
• Write a way to calculate the want invested in MyStrategy.balanceOfPool()
• Write a method that returns true if the Strategy should be tended in MyStrategy.isTendable()
• Set a version in MyStrategy.version()
• Invest your want tokens via Strategy._deposit().
• Take profits and repay debt via Strategy.harvest().
• Unwind enough of your position to payback withdrawals via Strategy._withdrawSome().
• Unwind all of your positions via Strategy._withdrawAll().
• Rebalance the Strategy positions via Strategy.tend().
• Make a list of all position tokens that should be protected against movements via Strategy.protectedTokens().

Specifying checks for ordinary operations in config/StrategyResolver

In order to snapshot certain balances, we use the Snapshot manager. This class helps with verifying that ordinary procedures (deposit, withdraw, harvest), happened correctly.

See /helpers/StrategyCoreResolver.py for the base resolver that all strategies use Edit /config/StrategyResolver.py to specify and verify how an ordinary harvest should behave

StrategyResolver

• Add Contract to check balances for in get_strategy_destinations (e.g. deposit pool, gauge, lpTokens)
• Write confirm_harvest to verify that the harvest was profitable
• Write confirm_tend to verify that tending will properly rebalance the strategy
• Specify custom checks for ordinary deposits, withdrawals and calls to earn by setting up hook_after_confirm_withdraw, hook_after_confirm_deposit, hook_after_earn

Add your custom testing

Check the various tests under /tests The file /tests/test_custom is already set up for you to write custom tests there See example tests in /tests/examples All of the tests need to pass! If a test doesn't pass, you better have a great reason for it!

Testing

To run the tests:

brownie test

Debugging Failed Transactions

Use the --interactive flag to open a console immediatly after each failing test:

brownie test --interactive

Within the console, transaction data is available in the history container:

>>> history
[<Transaction '0x50f41e2a3c3f44e5d57ae294a8f872f7b97de0cb79b2a4f43cf9f2b6bac61fb4'>,
 <Transaction '0xb05a87885790b579982983e7079d811c1e269b2c678d99ecb0a3a5104a666138'>]

Examine the TransactionReceipt for the failed test to determine what went wrong. For example, to view a traceback:

>>> tx = history[-1]
>>> tx.traceback()

To view a tree map of how the transaction executed:

>>> tx.call_trace()

See the Brownie documentation for more detailed information on debugging failed transactions.

Deployment

When you are finished testing and ready to deploy to the mainnet:

1. Import a keystore into Brownie for the account you wish to deploy from.
2. Run scripts/production_deploy.py with the following command:

$ brownie run scripts/production_deploy.py --network mainnet

You will be prompted to enter your desired deployer account and keystore password, and then the contracts will be deployed.

3. This script will deploy a Controller, a SettV3 and your strategy under upgradable proxies. It will also set your deployer account as the governance for the three of them so that you can configure them and control them during testing stage. The script will also set the rest of the permissioned actors based on the latest entries from the Badger Registry.

Production Parameters Verification

When you are done testing your contracts in production and they are ready for incorporation to the Badger ecosystem, the production_setup script can be ran to ensure that all parameters are set in compliance to Badger's production entities and contracts. You can run this script by doing the following:

1. Open the scripts/production_setup.py file and change the addresses for your strategy and vault mainnet addresses on lines 29 and 30.
2. Import a keystore into Brownie for the account currently set as governance for your contracts.
3. Run scripts/production_setup.py with the following command:

$ brownie run scripts/production_setup.py --network mainnet

You will be prompted to enter your governance account and keystore password, and then the the parameter verification and setup process will be executed.

4. This script will compare all existing parameters against the latest production parameters stored on the Badger Registry. In case of a mismatch, the script will execute a transaction to change the parameter to the proper one. Notice that, as a final step, the script will change the governance address to Badger's Governance Multisig; this will effectively relinquish the contract control from your account to the Badger Governance. Additionally, the script performs a final check of all parameters against the registry parameters.

Known issues

No access to archive state errors

If you are using Ganache to fork a network, then you may have issues with the blockchain archive state every 30 minutes. This is due to your node provider (i.e. Infura) only allowing free users access to 30 minutes of archive state. To solve this, upgrade to a paid plan, or simply restart your ganache instance and redploy your contracts.

Resources

• Example Strategy https://github.com/Badger-Finance/wBTC-AAVE-Rewards-Farm-Badger-V1-Strategy
• Badger Builders Discord https://discord.gg/Tf2PucrXcE
• Badger Discord channel
• Yearn Discord channel
• Brownie Gitter channel
• Alex The Entreprenerd on Twitter