module.exports = {
 // ...
 devServer: {
   port: 4201,
   proxy: {
    '/adminapi': {
     target: 'http://localhost:8180',
     ws: true,
     changeOrigin: true,
     pathRewrite: {
      '^/adminapi': ''
     }
    },
    '/portalapi/': {
     target: 'http://localhost:8185/',
     ws: true,
     changeOrigin: true,
     pathRewrite: {
      '^/portalapi': ''
     }
    },
    '/securityapi/': {
     target: 'http://localhost:8089/',
     ws: true,
     changeOrigin: true,
     pathRewrite: {
      '^/securityapi': ''
     }
    }
   },
   disableHostCheck: true, // 这是由于新版的webpack-dev-server出于安全考虑，默认检查hostname，如果hostname 不是配置内的，将中断访问。
 },
 //...
}

var vm = new Vue({
  el: '#app',
  data: {
  },
  beforeCreate: function () {
    that = this
  },
  methods:{
   fom(fmt){
    ...
   }
  },
  ....,
  filters: {
       dateformate: function (val) {
         return that.fom("yyyy-MM-dd")
       }
     }
  })