example.js

import fs from 'fs-extra'
import _ from 'lodash'
import path from 'path'

let componentsPath = path.resolve('src/components')

const contents = fs.readdirSync(componentsPath)
let _files = []
let _directories = []

if (contents) {
  _.forEach(contents, file => {
    let filePath = path.resolve(componentsPath, file)
    let stats = fs.statSync(filePath)
    let extension = path.extname(file);
    let filename = path.basename(file, extension)

    if (stats.isFile()) {
      _files.push(filename)
    } else if (stats.isDirectory()) {
      _directories.push(filename)
    }
  })
}

fs.writeFileSync(`${componentsPath}/index.js`, (() => {
  let output = ''

  _.forEach(_directories, name => {
    if (name === 'index') return

    output += `export * from './${name}';\n`
  })

  _.forEach(_files, name => {
    if (name === 'index') return

    output += `export * from './${name}';\n`
  })

  return output
})())