Casino Ethereum

This is a smart contract about a casino game contract based on ethereum

About the game

How to generate a random number?

Actually, generate a random number on ethereum is not a easy thing, but after many appempts and explorations by different developers, we could do this.

Maybe there are some other ways to generate random number, for simplicity, i will just show the code how we generate a random number.

const reveal = web3.utils.randomHex(32)
const commit = web3.utils.soliditySha3(reveal)

Then push the commit to ethereum by a transaction, and get a blockHash or that block.

const randomNumber = web3.utils.soliditySha3(reveal, blockHash)

The randomNumber is the final random number.

The way to generate random number was inspired by Dice2Win

The random number is random enough?

To be honestly, i can not tell that right now(maybe some days later).

But i could supply some statistic data(100 000 rows data), and specific frequency count.

| blockNumber | blockHash | reveal | randomNumber | modulo2 | modulo6 | modulo36 | modulo 100 |

You can get the source data in block_reveal_modulo_result.csv, there are some statistic image about each modulo.

Dependencies

1. nodejs, and make sure it's version above 8.0.0
2. npm
3. truffle
4. ganache

Build

1. First run npm install to install node_modules
2. Then run truffle compile

Run tests

1. run truffle test to execute tests

Deploy

1. Before deploy you need to add your owner mnemonic to truffle.js like this:

const HDWalletProvider = require("truffle-hdwallet-provider")
const mnemonic = '<----12 words---->'

module.exports = {
  networks: {
    development: {
      host: "localhost",
      port: 7545,
      network_id: "*"
    },
    ropsten: {
      provider: function() {
        return new HDWalletProvider(mnemonic, "https://ropsten.infura.io/<----YOUR_API_KEY---->")
      },
      network_id: 3,
      gas: 4000000
    }
  },
  solc: {
    optimizer: {
      enabled: true,
      runs: 200
    }
  }
}

2. run truffle deploy --network testnet to deploy contract to ropsten network
3. run truffle deploy --network mainnet to deploy contract to mainnet network