配置开发环境、测试环境、正式环境，开发环境的代理

config/index.js文件中，
build.assetsRoot + ‘/’ + build.assetsSubDirectory，就是打包的资源文件存放目录。

按照以下步骤配置完成之后，以后开发、打包，只要修改两个地方。
稍微改两个小地方，很方便，而且不会出错。
1、修改config/dev.env.js文件的API_ROOT。
2、修改config/index.js文件的host变量、port变量。
//开发环境，修改config/dev.env.js文件
‘use strict’
const merge = require(‘webpack-merge’)
const prodEnv = require(’./prod.env’)

module.exports = merge(prodEnv, {
NODE_ENV: ‘“development”’,
API_ROOT: ‘“https://partner-t.test.com”’
})

//测试环境，修改config/test.env.js文件（文件不存在，就新建一个）
‘use strict’
module.exports = {
NODE_ENV: ‘“testing”’,
API_ROOT: ‘“https://partner-t.test.com”’
}

//正式环境，修改config/prod.env.js文件
‘use strict’
module.exports = {
NODE_ENV: ‘“production”’,
API_ROOT: ‘“https://partner.test.com”’
}

//修改src/main.js文件
import Axios from ‘axios’
Vue.prototype.$axios = Axios
//配置接口URL
Axios.defaults.baseURL = process.env.API_ROOT

//修改config/index.js文件
‘use strict’
// Template version: 1.3.1
// see http://vuejs-templates.github.io/webpack for documentation.

const path = require(‘path’)

module.exports = {
dev: {

// Paths
assetsSubDirectory: 'static',
assetsPublicPath: '/',
proxyTable: {
  '/api': {
    //修改这里，指定接口的域名和端口
    target: process.env.API_ROOT,
    changeOrigin: true,
    pathRewrite: {
      '^/api': '/api'
    }
  },
},

// Various Dev Server settings
// host: '192.168.1.66', // can be overwritten by process.env.HOST
host: 'h-t.test.com', // can be overwritten by process.env.HOST
// host: 'localhost', // can be overwritten by process.env.HOST
port: 80, // can be overwritten by process.env.PORT, if port is in use, a free one will be determined
autoOpenBrowser: false,
errorOverlay: true,
notifyOnErrors: true,
poll: false, // https://webpack.js.org/configuration/dev-server/#devserver-watchoptions-


/**
 * Source Maps
 */

// https://webpack.js.org/configuration/devtool/#development
devtool: 'cheap-module-eval-source-map',

// If you have problems debugging vue-files in devtools,
// set this to false - it *may* help
// https://vue-loader.vuejs.org/en/options.html#cachebusting
cacheBusting: true,

cssSourceMap: true

},

build: {
// Template for index.html
index: path.resolve(__dirname, ‘…/dist/index.html’),

// Paths
assetsRoot: path.resolve(__dirname, '../dist'),
assetsSubDirectory: 'static',
assetsPublicPath: '/',

/**
 * Source Maps
 */

productionSourceMap: false,
// https://webpack.js.org/configuration/devtool/#production
devtool: '#source-map',

// Gzip off by default as many popular static hosts such as
// Surge or Netlify already gzip all static assets for you.
// Before setting to `true`, make sure to:
// npm install --save-dev compression-webpack-plugin
productionGzip: false,
productionGzipExtensions: ['js', 'css'],

// Run the build command with an extra argument to
// View the bundle analyzer report after build finishes:
// `npm run build --report`
// Set to `true` or `false` to always turn it on or off
bundleAnalyzerReport: process.env.npm_config_report

}
}