truffle-config.js

const HDWalletProvider = require("@truffle/hdwallet-provider");
const path = require("path");
require("dotenv").config();

const { VUE_APP_INFURA_PHRASE, VUE_APP_INFURA_KEY } = process.env;

module.exports = {
  contracts_directory: "./ethereum/contracts",
  contracts_build_directory: path.join(__dirname, "./src/contracts/build"),
  migrations_directory: "./ethereum/migrations",

  /**
   * 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: 8545, // Standard Ethereum port (default: none)
      network_id: "*" // Any network (default: none)
    },
    rinkeby: {
      provider() {
        return new HDWalletProvider(
          VUE_APP_INFURA_PHRASE,
          `https://rinkeby.infura.io/v3/${VUE_APP_INFURA_KEY}`
        );
      },
      network_id: 4,
      gas: 4500000,
      gasPrice: 10000000000
    }
  },

  // Set default mocha options here, use special reporters etc.
  mocha: {
    useColors: true
  },

  // Configure your compilers
  compilers: {
    solc: {
      version: "^0.7.1" // 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"
    }
  }
};