SMART_CONTRACT_DESIGN_PRINCIPLE.md

Smart Contract Design

Reference：https://medium.com/zeppelin-blog/onward-with-ethereum-smart-contract-security-97a827e47702

• Fail as early and loudly as possible: When error occur then throw, don't let contract execute the code below
  • reduce gas
  • reduce code execute when error occur
• Favor pull over push payments
• Order your function code: conditions, actions, interactions:
  • first, check all the pre-conditions.
  • then, make changes to your contract’s state.
  • finally, interact with other contracts.
• Be aware of platform limits: Be ware on EVM limitation.
• Write tests: Test on every single line.
• Fault tolerance and Automatic bug bounties
• Limit the amount of funds deposited
• Write simple and modular code
• Event start from Log
• Don’t write all your code from scratch

require vs throw

• require for a single check for i.e. a malformed input.
• throw when need to do something between the real check and the exception.