truffle-config.js

const path = require('path');
const HDWalletProvider = require('@truffle/hdwallet-provider');
const Web3 = require('web3');
const web3 = new Web3();
// const infuraKey = "fj4jll3k.....";
//

const fs = require('fs');

const secrets = JSON.parse(fs.readFileSync('secrets.json').toString().trim());

module.exports = {
  /**
   * 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>
   */
  contracts_build_directory: path.join(__dirname, 'client/src/contracts'),
  networks: {
    // live: {
    //   provider: () =>
    //     new HDWalletProvider(
    //       secrets.privateKeys,
    //       'https://mainnet.infura.io/v3/6a1f863988cd4960a2ee62e1799e58d5',
    //       0,
    //       4
    //     ),
    //   // network_id: liveNetworkId,
    //   gasPrice: web3.utils.toWei('10', 'gwei'),
    // },
    kovan: {
      provider: () => {
        return new HDWalletProvider(
          secrets.privateKeys,
          'https://kovan.infura.io/v3/6a1f863988cd4960a2ee62e1799e58d5',
          0,
          4
        );
      },

      network_id: 42,
      gas: 5500000,
      skipDryRun: true,
    },

    development: {
      host: '127.0.0.1',
      port: 7545, // Using gßanache as development network
      network_id: '*',
      // gasPrice: '20000000000',
      // gas:'6721975'
    },
    // ropsten: {
    //   provider: () => {
    //     return new HDWalletProvider(
    //       privateKeys,
    //       "https://ropsten.infura.io/v3/" + process.env.INFURA_API_KEY,
    //       0,
    //       1
    //     );
    //   },
    //   network_id: 3, // Ropsten's id
    //   gas: 5500000, // Ropsten has a lower block limit than mainnet
    //   skipDryRun: true
    // },
    // 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: 8545,            // Standard Ethereum port (default: none)
    //  network_id: "*",       // Any network (default: none)
    // },
    // Another network with more advanced options...
    // advanced: {
    // port: 8777,             // Custom port
    // network_id: 1342,       // Custom network
    // gas: 8500000,           // Gas sent with each transaction (default: ~6700000)
    // gasPrice: 20000000000,  // 20 gwei (in wei) (default: 100 gwei)
    // from: <address>,        // Account to send txs from (default: accounts[0])
    // websockets: true        // Enable EventEmitter interface for web3 (default: false)
    // },
    // Useful for deploying to a public network.
    // NB: It's important to wrap the provider as a function.
    // ropsten: {
    // provider: () => new HDWalletProvider(mnemonic, `https://ropsten.infura.io/v3/YOUR-PROJECT-ID`),
    // network_id: 3,       // Ropsten's id
    // gas: 5500000,        // Ropsten has a lower block limit than mainnet
    // confirmations: 2,    // # of confs to wait between deployments. (default: 0)
    // timeoutBlocks: 200,  // # of blocks before a deployment times out  (minimum/default: 50)
    // skipDryRun: true     // Skip dry run before migrations? (default: false for public nets )
    // },
    // Useful for private networks
    // private: {
    // provider: () => new HDWalletProvider(mnemonic, `https://network.io`),
    // network_id: 2111,   // This network is yours, in the cloud.
    // production: true    // Treats this network as if it was a public net. (default: false)
    // }
  },

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

  // Configure your compilers
  compilers: {
    solc: {
      version: '0.8.6', // 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: true,
        runs: 200,
      },
      //  evmVersion: "byzantium"
      // }
    },
  },
};