👯♂️ Multiplayer
Supporting multiple players
Last week we built out the core components of our Tic-tac-toe game: marking the board, validating moves, and checking for wins. This week, we'll turn the basic board framework into a multiplayer game, by restricting access to state changing functions to specific, authorized addresses. But first, we'll talk a little bit about what it means to run code on a public blockchain like Ethereum and take a detour to explore the basic board contract we wrote last week on a live test network.
Goals this week
- Add authorization to the game, so that moves can only originate from specific authorized addresses.
- Understand the unique properties of running code on a public blockchain.
- Learn about function modifiers, addresses, external vs contract accounts, and
msg.senderin Solidity.
Suggested homework
- Read All about modifiers.
- Read the Solidity docs on function modifiers and the address type.
- Examine the OpenZeppelin Ownable and ReentrancyGuard contracts to see how they make use of modifiers and
msg.sender. - Continue working through the Cryptozombies exercises at your own pace to learn basic Solidity syntax.
- If you're done with Cryptozombies, start exploring the Ethernaut interactive exercises.