alias: {
   // Support React Native Web
   // https://www.smashingmagazine.com/2016/08/a-glimpse-into-the-future-with-react-native-for-web/
   'react-native': 'react-native-web',
   // Allows for better profiling with ReactDevTools
   ...(isEnvProductionProfile && {
     'react-dom$': 'react-dom/profiling',
     'scheduler/tracing': 'scheduler/tracing-profiling',
   }),
   ...(modules.webpackAliases || {}),
},

alias: {
   // Support React Native Web
   // https://www.smashingmagazine.com/2016/08/a-glimpse-into-the-future-with-react-native-for-web/
   'react-native': 'react-native-web',
   // Allows for better profiling with ReactDevTools
   ...(isEnvProductionProfile && {
     'react-dom$': 'react-dom/profiling',
     'scheduler/tracing': 'scheduler/tracing-profiling',
   }),
   ...(modules.webpackAliases || {}),
   // 文件路徑別名
   '@': path.resolve(__dirname, '../src'),
   '@view': path.resolve(__dirname, '../src/view'),
}, 

  const proxy = require('http-proxy-middleware')
  module.exports = function(app) {
   app.use(
    proxy.createProxyMiddleware('/api', {  //帶有api是需要轉(zhuǎn)發(fā)的請(qǐng)求 
     target: 'http://localhost:4000',  // 這里是服務(wù)器地址
     changeOrigin: true,//值為布爾值, 為true時(shí), 本地就會(huì)虛擬一個(gè)服務(wù)器接收你的請(qǐng)求并代你發(fā)送該請(qǐng)求,
     pathRewrite: {'^/api': ''}
    })
   )
  }