DEX smart contract

The smart contract samples of some tokens for the Decentralized Exchange

Init smart contracts

If you have already put smart contracts in genesis block, just change the code from await BTM.deployed() to await BTM.at("address") then run truffle migrate -f 3 --to 3 --network development
Otherwise just run truffle deploy --network development

Architecture

The smart contract samples used to deploy in creation block. The tokens contracts for selling and buying, and the Exchange contract used to allows two users to interact with. There is no matching engine logic inside the exchange contract, it is supposed to have trade logic only.

Smart Contract API

To execute a trade, executeTrade needs to be called with the following arguments:

Argument	Type	Description
buyAmount	uint256	Amount of buyToken tokens the maker wants to buy
sellAmount	uint256	Amount of sellToken tokens the maker wants to sell
expires	uint256	Blocknumber at which the order will no longer be valuable
nonce	uint256	Random number to ensure uniqueness of the order
feeMake	uint256	Percentage of fee taken from maker token value
feeTake	uint256	Percentage of fee taken from taker token value
amount	uint256	Amount of buyToken the taker wants to sell
tradeNonce	uint256	Random number to ensure uniqueness of the trade
buyToken	address	Address of buyToken (token the maker wants to buy)
sellToken	address	Address of sellToken (token the maker wants to sell)
maker	address	Maker Address
taker	address	Taker Address
vMaker	uint8	Maker Signature v Parameter
vTaker	uint8	Taker Signature v Parameter
rMaker	bytes32	Maker Signature r Parameter
rTaker	bytes32	Maker Signature r Parameter
sMaker	bytes32	Maker Signature s Parameter
sTaker	bytes32	Maker Signature s Parameter

Each group of values must be packed together in array based on their type (See Exchange.sol)

To do a hard cancel, cancelOrder needs to be called with the following arguments

Argument	Type	Description
buyAmount	uint256	Amount of buyToken tokens the maker wants to buy
sellAmount	uint256	Amount of sellToken tokens the maker wants to sell
expires	uint256	Blocknumber at which the order will no longer be valuable
nonce	uint256	Random number to ensure uniqueness of the order
feeMake	uint256	Percentage of fee taken from maker token value
feeTake	uint256	Percentage of fee taken from taker token value
buyToken	address	Address of buyToken (token the maker wants to buy)
sellToken	address	Address of sellToken (token the maker wants to sell)
maker	address	Maker Address
v	uint8	Maker Signature v Parameter
r	bytes32	Maker Signature r Parameter
s	bytes32	Maker Signature s Parameter

Each group of values must be packed together in array based on their type (See Exchange.sol)

Development and Testing Environment Setup

Requirements :

• OSX or Linux (Windows setup is likely possible but not covered in this guide)
• Node (version 8.9.4 recommended)
• Solidity Compiler (v0.4.24)
• Ganache-cli (v6.1.3)
• Truffle (v4.1.12)
• npm (version 6.1.0)

Testing Environment Setup :

• Clone the repository and install dependencies

git clone git@github.com:tomochain/dex-smart-contract.git
cd dex-smart-contract
yarn

• Install the latest version of truffle (Truffle v4.0.6)

yarn global add truffle

• Compile contracts

truffle compile

• Initialize testrpc (or geth)

./start_rpc.sh

• Migrate contracts to chosen network

truffle migrate --network development

• Make sure you are using the latest version of node

nvm install 8.9.4
nvm use 8.9.4

• Fill in truffle.js and deploy_contracts.js with appropriate wallet addresses. Unlock the corresponding addresses.

• Verify all tests are passing.

You need to re-migrate all contracts before running the test suite

truffle migrate --reset && truffle test

• You can interact with the contracts via the console

truffle console

• You can watch for changes on the fileystem with:

npm run watch

• Lint

npm run lint

Contribution

This is a fork of the Proof project !

Please try your best to follow the guidance here:

https://chris.beams.io/posts/git-commit/

License

The smart contract (i.e. all code inside of the contracts and test directories) is licensed under the MIT License, also included in our repository in the LICENSE file.