text: require('./check-versions')()
  var config = require('../config')
  if (!process.env.NODE_ENV) process.env.NODE_ENV = config.dev.env
  var path = require('path')
  var express = require('express')
  var webpack = require('webpack')
  var opn = require('opn')
  var proxyMiddleware = require('http-proxy-middleware')
  var webpackConfig = require('./webpack.dev.conf')
  
  // default port where dev server listens for incoming traffic
  var port = process.env.PORT || config.dev.port
  // Define HTTP proxies to your custom API backend
  // https://github.com/chimurai/http-proxy-middleware
  var proxyTable = config.dev.proxyTable
  
  var app = express()
  var compiler = webpack(webpackConfig)
  
  var devMiddleware = require('webpack-dev-middleware')(compiler, {
    publicPath: webpackConfig.output.publicPath,
    stats: {
      colors: true,
      chunks: false
    }
  })
  
  var hotMiddleware = require('webpack-hot-middleware')(compiler)
  // force page reload when html-webpack-plugin template changes
  compiler.plugin('compilation', function (compilation) {
    compilation.plugin('html-webpack-plugin-after-emit', function (data, cb) {
      hotMiddleware.publish({ action: 'reload' })
      cb()
    })
  })
  
  // proxy api requests
  Object.keys(proxyTable).forEach(function (context) {
    var options = proxyTable[context]
    if (typeof options === 'string') {
      options = { target: options }
    }
    app.use(proxyMiddleware(context, options))
  })
  
  // handle fallback for HTML5 history API
  app.use(require('connect-history-api-fallback')())
  
  // serve webpack bundle output
  app.use(devMiddleware)
  
  // enable hot-reload and state-preserving
  // compilation error display
  app.use(hotMiddleware)
  
  // serve pure static assets
  var staticPath = path.posix.join(config.dev.assetsPublicPath, config.dev.assetsSubDirectory)
  app.use(staticPath, express.static('./static'))
  
  module.exports = app.listen(port, function (err) {
    if (err) {
      console.log(err)
      return
    }
    var uri = 'http://localhost:' + port
    console.log('Listening at ' + uri + '\n')
  
    // when env is testing, don't need open it
    // if (process.env.NODE_ENV !== 'testing') {
    //   opn(uri)
    // }
  })
  