VUE Error: getaddrinfo ENOTFOUND

Jins-MBP:helloworld XXX$ npm run dev

> helloworld@1.0.0 dev /Users/XXX/Documents/develop/front/helloworld
> webpack-dev-server --inline --progress --config build/webpack.dev.conf.js

 10% building modules 2/4 modules 2 active .../develop/front/helloworld/src/main.jsevents.js:183
      throw er; // Unhandled 'error' event
      ^

Error: getaddrinfo ENOTFOUND localhost
    at errnoException (dns.js:50:10)
    at GetAddrInfoReqWrap.onlookup [as oncomplete] (dns.js:92:26)
npm ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! helloworld@1.0.0 dev: `webpack-dev-server --inline --progress --config build/webpack.dev.conf.js`
npm ERR! Exit status 1
npm ERR!
npm ERR! Failed at the helloworld@1.0.0 dev script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.

npm ERR! A complete log of this run can be found in:
npm ERR!     /Users/XXX/.npm/_logs/2018-04-18T01_01_10_246Z-debug.log

根据报错内容，推断是localhost的问题。有可能是localhost没有绑定127.0.0.1。

修改方法：

添加host配置

127.0.0.1 localhost