Compound Money Market

The Compound Money Market holds all of the contracts used to implement the Compound protocol. Through the money market contract, users of the blockchain supply capital (Ether or ERC-20 tokens) to earn interest, or borrow capital by holding collateral in the contract. The money market contract tracks each of these balances, a balance sheet and automatically sets interest rates.

Before getting started, please read:

• The Compound Whitepaper, describing how Compound works
• The Compound Protocol Specification, explaining in plain English how the protocol operates

Contracts

We detail a few of the core contracts in the Compound protocol.

Money Market

The Compound Money Market.

Careful Math

Library for safe math operations.

ErrorReporter

Library for tracking error codes and failure conditions.

Exponential

Library for handling fixed-point decimal numbers.

InterestRateModel

Abstract contract defining an interest rate model. Its functions are specifically not marked pure as implementations of this contract may read from storage variables.

SafeToken

Library for safely handling ERC20 interaction.

StandardInterestRateModel

Initial interest rate model, as defined in the Whitepaper.

Installation

To run compound, pull the repository from GitHub and install its dependencies. You will need yarn or npm installed.

git clone https://github.com/compound-finance/compound-money-market
cd money-market
yarn

You can then compile and deploy the contracts with:

truffle compile
truffle migrate

Testing

Contract tests are defined under the test directory. To run the tests run:

scripts/test

or with inspection (visit chrome://inspect) and look for a remote target after running:

node --inspect node_modules/truffle-core/cli.js test

Assertions used in our tests are provided by ChaiJS.

Code Coverage

To run code coverage, simply run:

scripts/coverage

Linting

To lint the code, run:

scripts/lint

Deployment

To deploy the Money Market contracts run:

truffle deploy

Docker

To run in docker:

# Build the docker image
docker build -t money-market .

# Run a shell to the built image
docker run -it money-market /bin/sh

From within a docker shell, you can interact locally with the protocol via ganache and truffle:

> ganache-cli &
> truffle deploy
> truffle console
truffle(development)> MoneyMarket.deployed().then((contract) => moneyMarket = contract);
truffle(development)> moneyMarket.admin()
'0x842e5e1a348eb91fc68219ca70db83170ccd9a5e'

Test net

To deploy on test-net, run:

RINKEBY_PRIVATE_KEY=<...> truffle deploy --network rinkeby

where the private key refers to a rinkeby private key in hex form (e.g. this can be the value exported from MetaMask under Settings).

You can choose "rinkeby", "kovan" or "ropsten" as your test net.

Additionally, for not main-net, you can put your test-net private keys in a folder and set the environment variable (e.g. in your ~/.bash_profile):

ETHEREUM_NETWORKS_HOME=~/.ethereum

The project will search this directory for test-net keys, which you can add as such:

mkdir -p ~/.ethereum
# Store command via editor or:
pbpaste > ~/.ethereum/rinkeby
chmod 600 ~/.ethereum/rinkeby

Note: This method is not safe for production. Production keys should be kept on hardware wallets.

Development

For local development of a fully working market, you may consider running:

scripts/blockchain/deploy-mock-oracle development # deploys oracle with mock prices
scripts/blockchain/deploy development # deploys money market to local ganache
scripts/blockchain/set-oracle development # sets oracle
scripts/blockchain/deploy-tokens development # adds some fake tokens
scripts/blockchain/support-markets development # adds money market support for the tokens added above

To deploy a real oracle, you can have compound-oracle located at $pwd/../compound-oracle and then run:

scripts/blockchain/oracle-deploy development # deploys a price oracle
scripts/blockchain/deploy-tokens development # deploys some basic faucet tokens
scripts/blockchain/oracle-set-token-prices development # sets configured prices

If you wish to run with a price oracle you have deployed separately, you can run:

scripts/blockchain/set-oracle development <oracle_address>  # sets address allowed to post prices

Also, you can easily pull into a console for a given environment with the correct ABI and addresses:

scripts/blockchain/console development

truffle(development)> MoneyMarket.deployed().then((c) => moneyMarket = c);
truffle(development)> moneyMarket.collateralRatio().then((r) => r.toString())
'2000000000000000000'

Rinkeby

For rinkeby development of a fully working market, you will deploy a price oracle, tokens, configure the money market and then you're set.

Note: the examples expect you to have generated a poster key and address. The address of the poster can be stored, e.g. in ~/.ethereum/rinkeby-poster.addr, as detailed below.

scripts/blockchain/oracle-deploy rinkeby $(cat ~/.ethereum/rinkeby-poster.addr)

If you don't have test tokens on rinkeby, you can deploy them as such:

scripts/blockchain/deploy-tokens rinkeby # only run if not already tokens

Then, you'll either want to set default prices, and pull and post prices from exchanges (not pictured):

scripts/blockchain/oracle-set-token-prices rinkeby # alternatively, deploy a price poster

Finally, deploy the MoneyMarket, set the oracle, and support the markets.

scripts/blockchain/deploy rinkeby # deploys money market to rinkeby
scripts/blockchain/set-oracle rinkeby # sets oracle from previous deployment step
scripts/blockchain/support-markets rinkeby # adds money market support for the tokens added

Rinkeby -> Deplying New Oracle

The following steps should be taken to deploy a new oracle:

scripts/blockchain/oracle-deploy rinkeby $(cat ~/.ethereum/rinkeby-poster.addr)

Then, you'll either want to set default prices, and pull and post prices from exchanges (not pictured):

scripts/blockchain/oracle-set-token-prices rinkeby # sets default prices, esp. useful for weth

Once the oracle has prices set, you should then set it as the new oracle:

scripts/blockchain/set-oracle rinkeby # sets oracle from previous deployment step

Deploying New InterestRateModel

The following steps should be taken to update an interest rate model. The following example is for a Stable Coin.

Rinkeby

scripts/blockchain/update-interest-rate rinkeby TUSD StableCoinInterestRateModel please-update-money-market

Main-net

scripts/blockchain/update-interest-rate mainnet x0 StableCoinInterestRateModel

The new contract address will be written to the Networks config (and output as a result of the command). Use that address to call the Money Market interest rate model updates manually as an admin.

Main-net

For mainnet development of a fully working market, you will deploy a price oracle and configure the money market and then you're set.

scripts/blockchain/oracle-deploy mainnet $(cat ~/.ethereum/mainnet-poster.addr)

Deploy a poster service with the updated oracle address and verify prices for all supported assets are set.

Finally, deploy the MoneyMarket, set the oracle, and support the markets.

scripts/blockchain/deploy mainnet # deploys money market to mainnet
scripts/blockchain/set-oracle mainnet # sets oracle from previous deployment step
scripts/blockchain/support-markets mainnet # adds money market support for the tokens added

Console

You can easily pull into a console for a given environment with the correct ABI and addresses:

scripts/blockchain/console development

truffle(development)> MoneyMarket.deployed().then((c) => moneyMarket = c);
truffle(development)> moneyMarket.collateralRatio().then((r) => r.toString())
'2000000000000000000'

Discussion

For any concerns with the protocol, open an issue or visit us on Discord to discuss.

For security concerns, please email [email protected].

© Copyright 2018, Compound Labs