Vue项目打包后放在 /dist/ 目录下，如果想要service worker控制localhost下的子目录的话就需要把 service worker的js文件放在localhost下。
假设js文件为sw.js。所以我们可以修改build/webpack.base.conf.js,把sw.js复制到localhost下。
红色字体为添加部分。

var path = require('path')
var utils = require('./utils')
var config = require('../config')
var vueLoaderConfig = require('./vue-loader.conf')

var CopyWebpackPlugin = require(‘copy-webpack-plugin’)

function resolve (dir) {
  return path.join(__dirname, '..', dir)
}

module.exports = {
  entry: {
    app: './src/main.js'
  },
  output: {
    path: config.build.assetsRoot,
    filename: '[name].js',
    publicPath: process.env.NODE_ENV === 'production'
      ? config.build.assetsPublicPath
      : config.dev.assetsPublicPath
  },
  resolve: {
    extensions: ['.js', '.vue', '.json'],
    alias: {
      'vue$': 'vue/dist/vue.esm.js',
      '@': resolve('src')
    }
  },
  module: {
    rules: [
      {
        test: /\.(js|vue)$/,
        loader: 'eslint-loader',
        enforce: 'pre',
        include: [resolve('src'), resolve('test')],
        options: {
          formatter: require('eslint-friendly-formatter')
        }
      },
      {
        test: /\.vue$/,
        loader: 'vue-loader',
        options: vueLoaderConfig
      },
      {
        test: /\.js$/,
        loader: 'babel-loader',
        include: [resolve('src'), resolve('test')]
      },
      {
        test: /\.(png|jpe?g|gif|svg)(\?.*)?$/,
        loader: 'url-loader',
        options: {
          limit: 10000,
          name: utils.assetsPath('img/[name].[hash:7].[ext]')
        }
      },
      {
        test: /\.(woff2?|eot|ttf|otf)(\?.*)?$/,
        loader: 'url-loader',
        options: {
          limit: 10000,
          name: utils.assetsPath('fonts/[name].[hash:7].[ext]')
        }
      }
    ]
  }

,
plugins: [
// copy sw.js path.resolve(__dirname, ‘sw.js所在路径’)
new CopyWebpackPlugin([
{
from: path.resolve(__dirname, ‘../src/serviceWorker/sw.js’),
to: config.build.assetsRoot,
ignore: [‘.*’]
}
])
]

}