Nuxt/bin/nuxt-dev

#!/usr/bin/env node

// Show logs
process.env.DEBUG = 'nuxt:*'

const _ = require('lodash')
const debug = require('debug')('nuxt:build')
const fs = require('fs')
const Nuxt = require('../')
const Server = require('../lib/server')
const chokidar = require('chokidar')
const { resolve } = require('path')

const rootDir = resolve(process.argv.slice(2)[0] || '.')
const nuxtConfigFile = resolve(rootDir, 'nuxt.config.js')
let options = {}
if (fs.existsSync(nuxtConfigFile)) {
  options = require(nuxtConfigFile)
}
if (typeof options.rootDir !== 'string') {
  options.rootDir = rootDir
}

options.dev = true // Add hot reloading and watching changes

new Nuxt(options)
.then((nuxt) => {
  const server = new Server(nuxt)
  .listen(process.env.PORT || process.env.npm_package_config_nuxt_port, process.env.HOST || process.env.npm_package_config_nuxt_host)
  listenOnConfigChanges(nuxt, server)
})
.catch((err) => {
  console.error(err)
  process.exit(1)
})

function listenOnConfigChanges (nuxt, server) {
  // Listen on nuxt.config.js changes
  const build = _.debounce(() => {
    debug('[nuxt.config.js] changed, rebuilding the app...')
    delete require.cache[nuxtConfigFile]
    let options = {}
    if (fs.existsSync(nuxtConfigFile)) {
      options = require(nuxtConfigFile)
    }
    options.rootDir = rootDir
    nuxt.close()
    .then(() => {
      return new Nuxt(options)
    })
    .then((nuxt) => {
      server.nuxt = nuxt
    })
    .catch((error) => {
      console.error('Error while rebuild the app:', error)
      process.exit(1)
    })
  }, 200)
  const nuxtConfigFile = resolve(rootDir, 'nuxt.config.js')
  chokidar.watch(nuxtConfigFile, { ignoreInitial: true })
  .on('all', build)
}