compile.js

const path = require('path');
const fs = require('fs-extra');
const solc = require('solc');

const buildPath = path.resolve(__dirname, 'build');
const contractsFolderPath = path.resolve(__dirname, 'contracts');

const createBuildFolder = () => {
  fs.emptyDirSync(buildPath);
};

const buildSources = () => {
  const sources = {};
  const contractsFiles = fs.readdirSync(contractsFolderPath);

  contractsFiles.forEach((file) => {
    const contractFullPath = path.resolve(contractsFolderPath, file);
    sources[file] = {
      content: fs.readFileSync(contractFullPath, 'utf8'),
    };
  });

  return sources;
};

const input = {
  language: 'Solidity',
  sources: buildSources(),
  settings: {
    outputSelection: {
      '*': {
        '*': ['abi', 'evm.bytecode'],
      },
    },
  },
};

const compileContracts = () => {
  const compiledContracts = JSON.parse(
    solc.compile(JSON.stringify(input))
  ).contracts;

  for (let contract in compiledContracts) {
    for (let contractName in compiledContracts[contract]) {
      console.log(contract);
      fs.outputJsonSync(
        path.resolve(buildPath, `${contractName}.json`),
        compiledContracts[contract][contractName],
        {
          spaces: 2,
        }
      );
    }
  }
};

(function run() {
  createBuildFolder();
  compileContracts();
})();