A minimal example showing how to integrate 1inch with your smart contract

• python3
• ganache-cli

git clone https://github.com/smye/1inch-swap.git
cd 1inch-swap
python3 -m venv .venv
source .venv/bin/activate
pip install -r requirements.txt

• Add the OpenZeppelin dependencies via Brownies package manager

  brownie pm install OpenZeppelin/openzeppelin-contracts@4.1.0

• To add a live network to Brownie

  brownie networks add Ethereum polygon host=https://matic-mainnet.chainstacklabs.com  chainid=137 explorer=https://api.polygonscan.com/api

• For a development network

  brownie networks add Development polygon-fork host=http://127.0.0.1 cmd=ganache-cli fork=https://matic-mainnet.chainstacklabs.com port=8545

• Modify brownie-config.yaml

  • router: Address of the 1inch router
  • tokenIn: Input token address
  • tokenOut: Address of token to receive
  • amount: Amount of tokenIn being swapped
  • slippage: Percentage that amount of tokenOut can deviate from the quote by, before reverting
  • chain_id: Chain ID of the current network, used for querying 1inch API

• Set the PRIVATE_KEY environment variable (for live networks)

  export PRIVATE_KEY=0x....

• To deploy the SwapProxy contract on a mainnet-fork

  brownie run deploy_swap.py --network polygon-fork --interactive

• To execute a swap on an already deployed SwapProxy contract on a mainnet-fork

  brownie run swap.py --network polygon-fork --interactive

• Deploying on mainnet is exactly the same, but replace polygon-fork with polygon

• By default the account used in a forked environment is defined in the get_acc() function in swap.py

• The slippage protection (minOut) isn't strictly required in the contract as it is provided in the swap_req["tx"]["data"] value returned by the 1inch API, however, it is an additional failsafe