Vue.js 2.x Development Build With Hot Reloading For External Server (using Webpack template)

September 12, 2017

NOTE: Refer to this for latest guide.

This article assuming you created your project using webpack template.

vue init webpack <PROJECT_NAME>

Open package.json and observe the scripts section. You realize there is dev to spin up a development server with hot reload and build for production release. There isn’t an option for development release with hot reloading (watch mode).

Note: if you are not using webpack, you can use vue build index.js --watch to enable watch mode.

...
  "scripts": {
    "dev": "node build/dev-server.js",
    "start": "node build/dev-server.js",
    "build": "node build/build.js",
    "unit": "cross-env BABEL_ENV=test karma start test/unit/karma.conf.js --single-run",
    "e2e": "node test/e2e/runner.js",
    "test": "npm run unit && npm run e2e",
    "lint": "eslint --ext .js,.vue src test/unit/specs test/e2e/specs"
  },
...

Edit package.json to add watch.

```text
...
  "scripts": {
  	...
  	"watch": "node build/watch-build-dev.js"
  },
...

Copy build/build.js to build/watch-build-dev.js, and edit as per following (changes are commented with EDIT).

require('./check-versions')()

// EDIT: process.env.NODE_ENV = 'production'
process.env.NODE_ENV = 'development'

var ora = require('ora')
var rm = require('rimraf')
var path = require('path')
var chalk = require('chalk')
var webpack = require('webpack')
var config = require('../config')
// EDIT: var webpackConfig = require('./webpack.prod.conf')
var webpackConfig = require('./webpack.watch.conf')

// EDIT: ora('building for production...')
var spinner = ora('building for development...')
spinner.start()

rm(path.join(config.build.assetsRoot, config.build.assetsSubDirectory), err => {
  if (err) throw err
  webpack(webpackConfig, function (err, stats) {
    spinner.stop()
    if (err) throw err
    process.stdout.write(stats.toString({
      colors: true,
      modules: false,
      children: false,
      chunks: false,
      chunkModules: false
    }) + '\n\n')

    // EDIT: remove the following to avoid watch quit upon error
    /*
    if (stats.hasErrors()) {
      console.log(chalk.red('  Build failed with errors.\n'))
      process.exit(1)
    }
     */

    console.log(chalk.cyan('  Build complete.\n'))
    // EDIT: remove
    /*
    console.log(chalk.yellow(
      '  Tip: built files are meant to be served over an HTTP server.\n' +
      '  Opening index.html over file:// won\'t work.\n'
    ))
     */
  })
})

Copy build/webpack.dev.conf.js to build/webpack.watch.conf.js, and edit as per following (changes are commented with EDIT).

Update 2017-11-26: for vue-cli-template-webpack 1.2.4, copy build/webpack.prod.conf.js to build/webpack.watch.conf.js, and edit as per following (changes are commented with EDIT)

'use strict'
const path = require('path')
const utils = require('./utils')
const webpack = require('webpack')
const config = require('../config')
const merge = require('webpack-merge')
const baseWebpackConfig = require('./webpack.base.conf')
const CopyWebpackPlugin = require('copy-webpack-plugin')
const HtmlWebpackPlugin = require('html-webpack-plugin')
const ExtractTextPlugin = require('extract-text-webpack-plugin')
const OptimizeCSSPlugin = require('optimize-css-assets-webpack-plugin')

// EDIT: change to development
// const env = require('../config/prod.env')
const env = require('../config/dev.env')

const webpackConfig = merge(baseWebpackConfig, {
  module: {
    rules: utils.styleLoaders({
      sourceMap: config.build.productionSourceMap,
      extract: true,
      usePostCSS: true
    })
  },
  devtool: config.build.productionSourceMap ? config.build.devtool : false,
  output: {
    path: config.build.assetsRoot,
    // EDIT: remove hash
    // filename: utils.assetsPath('js/[name].[chunkhash].js'),
    // chunkFilename: utils.assetsPath('js/[id].[chunkhash].js')
    filename: utils.assetsPath('js/[name].js'),
    chunkFilename: utils.assetsPath('js/[id].js')
  },
  plugins: [
    // http://vuejs.github.io/vue-loader/en/workflow/production.html
    new webpack.DefinePlugin({
      'process.env': env
    }),
    // UglifyJs do not support ES6+, you can also use babel-minify for better treeshaking: https://github.com/babel/minify
    // EDIT: disable js minify
    /*
    new webpack.optimize.UglifyJsPlugin({
      compress: {
        warnings: false
      },
      sourceMap: config.build.productionSourceMap,
      parallel: true
    }),
     */
    // extract css into its own file
    new ExtractTextPlugin({
      // EDIT: remove hash
      // filename: utils.assetsPath('css/[name].[contenthash].css'),
      filename: utils.assetsPath('css/[name].css'),
      // set the following option to `true` if you want to extract CSS from
      // codesplit chunks into this main css file as well.
      // This will result in *all* of your app's CSS being loaded upfront.
      // EDIT: if not then splitting vendor.css will cause javascript error
      // allChunks: false,
      allChunks: true,
    }),
    // Compress extracted CSS. We are using this plugin so that possible
    // duplicated CSS from different components can be deduped.
    // EDIT: disable CSS minify
    /*
    new OptimizeCSSPlugin({
      cssProcessorOptions: config.build.productionSourceMap
      ? { safe: true, map: { inline: false } }
      : { safe: true }
    }),
     */
    // generate dist index.html with correct asset hash for caching.
    // you can customize output by editing /index.html
    // see https://github.com/ampedandwired/html-webpack-plugin
    new HtmlWebpackPlugin({
      filename: config.build.index,
      template: 'index.html',
      inject: true,
      // EDIT: disable minify
      /*
      minify: {
        removeComments: true,
        collapseWhitespace: true,
        removeAttributeQuotes: true
        // more options:
        // https://github.com/kangax/html-minifier#options-quick-reference
      },
       */
      minify: false,
      // necessary to consistently work with multiple chunks via CommonsChunkPlugin
      chunksSortMode: 'dependency'
    }),
    // keep module.id stable when vender modules does not change
    new webpack.HashedModuleIdsPlugin(),
    // enable scope hoisting
    // EDIT:
    // new webpack.optimize.ModuleConcatenationPlugin(),
    // split vendor js into its own file
    new webpack.optimize.CommonsChunkPlugin({
      name: 'vendor',
      minChunks: function (module) {
        // any required modules inside node_modules are extracted to vendor
        // EDIT
        return (
          module.resource &&
          /\.(js|css|sass|scss|less)$/.test(module.resource) &&
          module.resource.indexOf(
            path.join(__dirname, '../node_modules')
          ) === 0
        )
      }
    }),
    // extract webpack runtime and module manifest to its own file in order to
    // prevent vendor hash from being updated whenever app bundle is updated
    new webpack.optimize.CommonsChunkPlugin({
      name: 'manifest',
      minChunks: Infinity
    }),
    // This instance extracts shared chunks from code splitted chunks and bundles them
    // in a separate chunk, similar to the vendor chunk
    // see: https://webpack.js.org/plugins/commons-chunk-plugin/#extra-async-commons-chunk
    new webpack.optimize.CommonsChunkPlugin({
      name: 'app',
      async: 'vendor-async',
      children: true,
      minChunks: 3
    }),

    // copy custom static assets
    new CopyWebpackPlugin([
      {
        from: path.resolve(__dirname, '../static'),
        to: config.build.assetsSubDirectory,
        ignore: ['.*']
      }
    ])
  ],
  // EDIT: enable watch
  watch: true,
  // EDIT: enable watch for modules
  // https://github.com/vuejs-templates/webpack/issues/378
  watchOptions: {
    aggregateTimeout: 300,
    poll: 1000
  }
})

if (config.build.productionGzip) {
  const CompressionWebpackPlugin = require('compression-webpack-plugin')

  webpackConfig.plugins.push(
    new CompressionWebpackPlugin({
      asset: '[path].gz[query]',
      algorithm: 'gzip',
      test: new RegExp(
        '\\.(' +
        config.build.productionGzipExtensions.join('|') +
        ')$'
      ),
      threshold: 10240,
      minRatio: 0.8
    })
  )
}

if (config.build.bundleAnalyzerReport) {
  const BundleAnalyzerPlugin = require('webpack-bundle-analyzer').BundleAnalyzerPlugin
  webpackConfig.plugins.push(new BundleAnalyzerPlugin())
}

module.exports = webpackConfig

Run npm run watch to enable development build in watch mode.

Note: if you include global scope CSS, remember to import them at main.js.

npm run watch
# output
> hello@1.0.0 watch /code/vue/hello
> node build/watch-build-dev.js

⠙ building for development...

 DONE  Compiled successfully in 2923ms                                5:32:25 PM

Hash: fcfe8096ae777ea47bf7
Version: webpack 2.7.0
Time: 2923ms
             Asset       Size  Chunks                    Chunk Names
            app.js     780 kB       0  [emitted]  [big]  app
static/css/app.css   93 bytes       0  [emitted]         app
        index.html  845 bytes          [emitted]         

  Build complete.

Output shall be created at dist folder. You can use symbolic link (ln -s /code/vue/hello/dist/app.js) to link to these files from you external server (e.g. nginx) development directory. You can use something like livereload on the external server development directory to reload if changes are detected.

This work is licensed under a
Creative Commons Attribution-NonCommercial 4.0 International License.