truffle-config.js

/**
 * Use this file to configure your truffle project. It's seeded with some
 * common settings for different networks and features like migrations,
 * compilation and testing. Uncomment the ones you need or modify
 * them to suit your project as necessary.
 *
 * More information about configuration can be found at:
 *
 * trufflesuite.com/docs/advanced/configuration
 *
 * To deploy via Infura you'll need a wallet provider (like @truffle/hdwallet-provider)
 * to sign your transactions before they're sent to a remote public node. Infura accounts
 * are available for free at: infura.io/register.
 *
 * You'll also need a mnemonic - the twelve word phrase the wallet uses to generate
 * public/private key pairs. If you're publishing your code to GitHub make sure you load this
 * phrase from a file you've .gitignored so it doesn't accidentally become public.
 *
 */

// create a file at the root of your project and name it .env -- there you can set process variables
// like the mnemomic below. Note: .env is ignored by git in this project to keep your private information safe
require('dotenv').config();
const kovanMnemonic = process.env["KOVAN_MNEMONIC"];
const infuraKey = process.env["INFURA_KEY"];

const HDWalletProvider = require('@truffle/hdwallet-provider');

module.exports = {
  /**
  * contracts_build_directory tells Truffle where to store compiled contracts
  */
  contracts_build_directory: './client/contracts/ethereum-contracts',

  /**
  * contracts_directory tells Truffle where to find your contracts
  */
  contracts_directory: './contracts/ethereum',

  /**
   * Networks define how you connect to your ethereum client and let you set the
   * defaults web3 uses to send transactions. If you don't specify one truffle
   * will spin up a development blockchain for you on port 9545 when you
   * run `develop` or `test`. You can ask a truffle command to use a specific
   * network from the command line, e.g
   *
   * $ truffle test --network <network-name>
   */

  networks: {
    // Useful for testing. The `development` name is special - truffle uses it by default
    // if it's defined here and no other network is specified at the command line.
    // You should run a client (like ganache-cli, geth or parity) in a separate terminal
    // tab if you use this network and you must also set the `host`, `port` and `network_id`
    // options below to some value.
    //
    development: {
      host: "127.0.0.1",     // Localhost (default: none)
      port: 7545,            // Standard Ethereum port (default: none)
      network_id: "*",       // Any network (default: none)
    },
    local_ethereum: {
      network_id: 31337,
      host: '127.0.0.1',
      port: 9545,
      gasPrice: 0
    },
    kovan: {
      network_id: 42,
      chain_id: 42,
      provider: function() {
        return new HDWalletProvider(kovanMnemonic, "https://kovan.infura.io/v3/"+ infuraKey, 0, 1);
      }
    },
    rinkeby: {
      network_id: 4,
      chain_id: 4,
      provider: function() {
        return new HDWalletProvider(kovanMnemonic, "https://rinkeby.infura.io/v3/"+ infuraKey, 0, 1);
      }
    }
  },

  // Set default mocha options here, use special reporters etc.
  mocha: {
    // timeout: 100000
  },

  // Configure your compilers
  compilers: {
    solc: {
      version: "0.8.13",    // Fetch exact version from solc-bin (default: truffle's version)
      // docker: true,        // Use "0.5.1" you've installed locally with docker (default: false)
      // settings: {          // See the solidity docs for advice about optimization and evmVersion
      //  optimizer: {
      //    enabled: false,
      //    runs: 200
      //  },
      //  evmVersion: "byzantium"
      // }
    }
  },
  db: {
    enabled: false
  }
};