README.md

ETH BSC Swap Contracts

Overview

ETH BSC Swap Contracts are responsible for registering swap pairs and swapping assets between ETH and BSC.

Register swap pair

1. Users register swap pair for erc20 token on ETH via ETHSwapAgent(createSwapPair) if token is not registered.

2. Swap service will monitor the SwapPairRegister event and create swap pair on BSC:

   1. create an BEP20 token on BSC
   2. record the relation between erc20 token and bep20 token.

Swap from ETH to BSC

Once swap pair is registered, users can swap tokens from ETH to BSC.

1. Users call swapETH2BSC via ETHSwapAgent and specify erc20 token address, amount and swap fee.
2. Swap service will monitor the SwapStarted event and call fillETH2BSCSwap via BSCSwapAgent to mint corresponding bep20 tokens to the same address that initiate the swap.

Swap from BSC to ETH

Once swap pair is registered, users can swap tokens from BSC to ETH.

1. Users call swapBSC2ETH via BSCSwapAgent and specify bep20 token address, amount and swap fee. Bep20 tokens will be burned.
2. Swap service will monitor the SwapStarted event and call fillBSC2ETHSwap via BSCSwapAgent to transfer corresponding erc20 tokens to the same address that initiate the swap.

Environment

1. Make a copy of .env.template named .env

2. Replace the YOUR_INFURA_KEY with the Infura API key of yours.

3. Put the private keys in OWNER_PRIVKEY and ADMIN_PRIVKEY fields.

• OWNER_PRIVKEY is the key of the account deploying the smart contracts. This key will be used in backend to call the smart contract.
• ADMIN_PRIVKEY is the key of the admin account of the proxy contract.

Please keep the private keys in safe storage.

4. Put the scanner API keys in ETHERSCAN_API_KEY and BSCSCAN_API_KEY fields.

Test

Run the development network:

npm run testrpc

Deploy to development network:

npx truffle migrate --reset

Run tests:

npx truffle test

Run coverage:

npm run coverage

Deply & Verify

Deploy

npx truffle migrate --network ropsten --reset

Please put the registerTx to ETH_REGISTER_TX in .env

npx truffle migrate --network bsctestnet --reset

BSC DVG token must give a minter role to the deployed BSCSwapAgentUpgradeableProxy contract.

Verify

npx truffle run verify ETHSwapAgentImpl --network ropsten
npx truffle run verify ETHSwapAgentUpgradeableProxy --network ropsten

npx truffle run verify BEP20TokenImplementation --network bsctestnet
npx truffle run verify BSCSwapAgentImpl --network bsctestnet
npx truffle run verify BSCSwapAgentUpgradeableProxy --network bsctestnet