replaceEnvVarInPublicDirectory.js

/**
 * @description
 * this script for replace environment variable from public directory
 * of Create-React-App.
 *
 * Problem
 * create-react-app can't work with ENV_VAR for all javascript files
 * in public directory
 * on running build script.
 *
 * Solve
 * this little script for change all env var in the public directory
 * @author ri7nz <[email protected]>
 *
 */

const dotEnv = require('dotenv')
const replacer = require('replace-in-files')

const { NODE_ENV: ENV } = process.env

if (ENV) {
  const parseEnv = dotEnv.config('.env' + ENV !== '' ? '.' + ENV : '').parsed

  Object.keys(parseEnv)
    .filter(env => env.startsWith('REACT_APP'))
    .forEach(env => {
      const replacerOptions = {
        // after build, all of javascript file on public directory
        // is copied in build directory
        files: 'build/*.js',
        from: new RegExp(env, 'g'),
        to: parseEnv[env],
      }

      const onReplace = e => {
        const { changedFiles } = e
        console.log('Modified Files:', changedFiles)
        console.log('From env name:' + env + ' With Value:' + parseEnv[env])
      }
      replacer(replacerOptions).then(onReplace)
    })
} else {
  console.warn(
    'Please use NODE_ENV=your_env_state\n' +
      '$ NODE_ENV=development node me.js',
  )
}