pyth-network_pyth-crosschain/target_chains/ethereum/examples/coin_flip

Coin Flip Example application

The coin flip example demonstrates how to use Pyth Entropy to flip a fair coin.

Try it out

To try the example, first run the following commands from the root of the pyth-crosschain repository:

npm install
npx lerna run build

These commands will build dependencies for the typescript project.

Next, choose a network to run the example on. The example has been deployed on the following networks:

| Chain Name | Address | RPC | | optimism-goerli | 0x075A5160FF6462924B4124595F6f987187496476 | https://goerli.optimism.io |

You will also need the private key of a wallet with some gas tokens for your chosen network. Then, from the coin_flip/app directory, run the following command:

npm run flip-coin -- \
  --private-key <hexadecimal evm private key> \
  --chain-name <chain name> \
  --address <address> \
  --rpc-url <rpc url>

You can populate the arguments to this command from the table above. The command should print output like this:

Running coin flip prototcol.
1. Generating user's random number...
   number    : 0x79b029406af43b11937bca98c49633f9382ed7d3fc0d60e110258c5c8f0d1a05
   commitment: 0xd4bca63083f9fb9e83e68348cb48f45babd820fc3559c60ba9a67b0ab3845cea
2. Requesting coin flip...
   fee       : 87 wei
   tx        : 0x3a59bb8c1aaa8c6ff97147bb3197e9b89c0d87174b0b6c32374fc62de6d8db94
   sequence  : 50
3. Retrieving provider's random number...
   fetch url : https://fortuna-staging.pyth.network/v1/chains/optimism-goerli/revelations/50
   number    : 0x760e53a19a4677ef671fde63db59462dfb3e09e94418e9962e2fa764026b8400
4. Revealing the result of the coin flip...
   tx        : 0x0549b93b12684187f73ddcaf8351ca4049867882c1b138989e15363a4d103220
   result    : tails

Understanding the Example

The example consists of a Solidity contract and a Typescript script. See the extensive code comments in the contract at contract/src/CoinFlip.sol to learn how the example works. The typescript script is available at app/src/flip_coin.ts and demonstrates how to interact with the contract.