vue.config.js

const path = require('path')
function resolve (dir) {
  return path.join(__dirname, dir)
}
function getProxy (path, type) {
  if (path === '/api') {
    switch (type) {
      case 'localhost':
        return 'http://localhost:1313'
      case 'service':
        return 'https://www.lyh.red'
    }
  }
}
module.exports = {
  publicPath: './',
  outputDir: 'bbs',
  assetsDir: 'static',
  lintOnSave: process.env.NODE_ENV === 'development',
  productionSourceMap: false,
  devServer: {
    port: 9005,
    open: false,
    overlay: {
      warnings: true,
      errors: true
    },
    proxy: {
      '/api': {
        target: getProxy('/api', process.env.VUE_APP_TYPE),
        pathRewrite: {
          '^/api': '/api'
        }
      }
    }
  },
  chainWebpack: config => {
    config.plugins.delete('preload')
    config.plugins.delete('prefetch')
    // 忽略的打包文件
    config.externals({
      'vue': 'Vue',
      'vue-router': 'VueRouter',
      'vuex': 'Vuex',
      'axios': 'axios',
      'element-ui': 'ELEMENT',
      "echarts": 'echarts'
    })
    const entry = config.entry('app')
    entry
      .add('babel-polyfill')
      .end()
    //修改文件引入自定义路径
    config.resolve.alias
      .set('@', resolve('src'))
      .end()
    // 图片压缩
    config.module
      .rule('images')
      .use('image-webpack-loader')
      .loader('image-webpack-loader')
      .options({
        bypassOnDebug: true
      })
      .end()
    // set preserveWhitespace
    config.module
      .rule('vue')
      .use('vue-loader')
      .loader('vue-loader')
      .tap(options => {
        options.compilerOptions.preserveWhitespace = true
        return options
      })
      .end()
    config
      // https://webpack.js.org/configuration/devtool/#development
      .when(process.env.NODE_ENV === 'development',
        config => config.devtool('cheap-source-map')
      )
    config
      .when(process.env.NODE_ENV !== 'development',
        config => {
          config
            .plugin('ScriptExtHtmlWebpackPlugin')
            .after('html')
            .use('script-ext-html-webpack-plugin', [{
            // `runtime` must same as runtimeChunk name. default is `runtime`
              inline: /runtime\..*\.js$/
            }])
            .end()
          config
            .optimization.splitChunks({
              chunks: 'all',
              cacheGroups: {
                libs: {
                  name: 'chunk-libs',
                  test: /[\\/]node_modules[\\/]/,
                  priority: 10,
                  chunks: 'initial' // only package third parties that are initially dependent
                },
                elementUI: {
                  name: 'chunk-elementUI', // split elementUI into a single package
                  priority: 20, // the weight needs to be larger than libs and app or it will be packaged into libs or app
                  test: /[\\/]node_modules[\\/]_?element-ui(.*)/ // in order to adapt to cnpm
                },
                commons: {
                  name: 'chunk-commons',
                  test: resolve('src/components'), // can customize your rules
                  minChunks: 3, //  minimum common number
                  priority: 5,
                  reuseExistingChunk: true
                }
              }
            })
          config.optimization.runtimeChunk('single')
        }
      )
      if (config.productionGzip) {
        const CompressionWebpackPlugin = require('compression-webpack-plugin');
        //增加浏览器CPU（需要解压缩）， 减少网络传输量和带宽消耗 （需要衡量，一般小文件不需要压缩的）
        //图片和PDF文件不应该被压缩，因为他们已经是压缩的了，试着压缩他们会浪费CPU资源而且可能潜在增加文件大小。
        webpackConfig.plugins.push(
            new CompressionWebpackPlugin({
                asset: '[path].gz[query]',
                algorithm: 'gzip',
                test: /\.(js|css)$/,
                threshold: 10240,//达到10kb的静态文件进行压缩 按字节计算
                minRatio: 0.8,//只有压缩率比这个值小的资源才会被处理
                deleteOriginalAssets: false//使用删除压缩的源文件
            })
        )
    }
  }
}