element plus重启后加载很慢 element按需加载_echarts世界地图json文件


最近优化了一个vue cli3.0项目,项目从打包体积2.5M,优化到272k, 速度提高了约2/3。下面将优化方法写下:

需要新建文件' vue.config.js',(这文件名是固定这么写的),与 package.json在同一级目录下。

BundleAnalyzer

作用:展示打包图形化信息,会打开一个html页面,帮助自己分析哪些文件过大,可针对其进行优化,上线前 注释掉

安装 webpack-bundle-analyzer 插件


npm install webpack-bundle-analyzer --save-dev


vue.config.js: 里面:


// 引入
const BundleAnalyzerPlugin = require("webpack-bundle-analyzer").BundleAnalyzerPlugin;

// 展示图形化信息
chainWebpack: config => {
  config
      .plugin('webpack-bundle-analyzer')
      .use(BundleAnalyzerPlugin)
}


抽离 css 支持按需加载

安装 mini-css-extract-plugin 插件


npm install mini-css-extract-plugin -D


vue.config.js里面:


chainWebpack: config => {
  let miniCssExtractPlugin = new MiniCssExtractPlugin({
    filename: 'assets/[name].[hash:8].css',
    chunkFilename: 'assets/[name].[hash:8].css'
  })
  config.plugin('extract-css').use(miniCssExtractPlugin)
}


图片按需加载

安装image-webpack-loader插件


npm install image-webpack-loader -D


vue.config.js里面:


config.module.rule('images')
    .test(/.(png|jpe?g|gif|webp)(?.*)?$/)
    .use('image-webpack-loader')
    .loader('image-webpack-loader')
    .options({
      bypassOnDebug: true
    })
    .end()


图片压缩可以在: https:// tinypng.com/ 进行批量压缩

gzip压缩代码

安装 compression-webpack-plugin 插件


npm install compression-webpack-plugin -D


vue.config.js里面:


const CompressionWebpackPlugin = require('compression-webpack-plugin');

// 开启gzip压缩
  config.plugins.push(
    new CompressionWebpackPlugin(
      {
        filename: info => {
          return `${info.path}.gz${info.query}`
        },
        algorithm: 'gzip',
        threshold: 10240, // 只有大小大于该值的资源会被处理 10240
        test: new RegExp('.(' + ['js'].join('|') + ')$'
        ),
        minRatio: 0.8, // 只有压缩率小于这个值的资源才会被处理
        deleteOriginalAssets: false // 删除原文件
      }
    )
  )


公共代码抽离

vue.config.js里面:


// 开启gzip压缩

configureWebpack: config => {
  config.plugins.push(
    new CompressionWebpackPlugin(
      {
        filename: info => {
          return `${info.path}.gz${info.query}`
        },
        algorithm: 'gzip',
        threshold: 10240, // 只有大小大于该值的资源会被处理 10240
        test: new RegExp('.(' + ['js'].join('|') + ')$'
        ),
        minRatio: 0.8, // 只有压缩率小于这个值的资源才会被处理
        deleteOriginalAssets: false // 删除原文件
      }
    )
  )
}


element-ui 按需加载

安装 babel-plugin-component 插件


npm install babel-plugin-component --save-dev


babel.config.js里面:


module.exports = {
  presets: [
    '@vue/app'
  ],
  plugins: [
    [
      "component",
      {
        libraryName: "element-ui",
        styleLibraryName: "theme-chalk"
      }
    ]
  ]
}


echarts 按需加载:

安装 babel-plugin-equire 插件:


npm install babel-plugin-equire -D


在项目中创建 echarts.js:


// eslint-disable-next-line
  const echarts = equire([
    // 写上你需要的 echarts api
    "tooltip",
    "line"
  ]);

  export default echarts;


babel.config.js里面:


module.exports = {
  presets: [
    '@vue/app'
  ],
  plugins: [
    [
      "component",
      {
        libraryName: "element-ui",
        styleLibraryName: "theme-chalk"
      }
    ],
    "equire"
  ]
}


具体页面应用:


// 直接引用
 import echarts from '@/lib/util/echarts.js' 
 
 this.myChart = echarts.init(this.$refs.chart)


lodash 按需加载:

安装 lodash-webpack-plugin 插件


npm install lodash-webpack-plugin --save-dev


babel.config.js里面:


module.exports = {
  presets: [
    '@vue/app'
  ],
  plugins: [
    [
      "component",
      {
        libraryName: "element-ui",
        styleLibraryName: "theme-chalk"
      }
    ],
    "lodash",
    "equire"
  ]
}


vue.config.js里面:


const LodashModuleReplacementPlugin = require("lodash-webpack-plugin");

chainWebpack: config => {
    config
    .plugin("loadshReplace")
    .use(new LodashModuleReplacementPlugin());
}


prefetch 和 preload

删除无用的插件,避免加载多余的资源(如果不删除的话,则会在 index.html 里面加载 无用的 js 文件)


chainWebpack: config => {
    // 移除prefetch插件,避免加载多余的资源
    config.plugins.delete('prefetch')
    / 移除 preload 插件,避免加载多余的资源
    config.plugins.delete('preload');
}


完整的代码:


const MiniCssExtractPlugin = require('mini-css-extract-plugin');
const CompressionWebpackPlugin = require('compression-webpack-plugin');
const LodashModuleReplacementPlugin = require("lodash-webpack-plugin");

module.exports = {
  productionSourceMap: false, // 关闭生产环境的 source map
  lintOnSave: false,
  publicPath: process.env.VUE_APP_PUBLIC_PATH,
  devServer: {
    host: "localhost",
    port: 3002,
    proxy: {
      '/api': {
        target: "https://tapi.quanziapp.com/api/",
        ws: true,
        changeOrigin: true,
        pathRewrite: {
          '^/api': ''
        }
      },
    }
  },

  chainWebpack: config => {

    // 移除 prefetch 插件
    config.plugins.delete('prefetch');
    // 移除 preload 插件,避免加载多余的资源
    config.plugins.delete('preload');
 
    config.optimization.minimize(true);

    config.optimization.splitChunks({
      chunks: 'all'
    })

    config
      .plugin('webpack-bundle-analyzer')
      .use(require('webpack-bundle-analyzer').BundleAnalyzerPlugin)

    if (process.env.NODE_ENV !== 'development') {

      let miniCssExtractPlugin = new MiniCssExtractPlugin({
        filename: 'assets/[name].[hash:8].css',
        chunkFilename: 'assets/[name].[hash:8].css'
      })
      config.plugin('extract-css').use(miniCssExtractPlugin)
      config.plugin("loadshReplace").use(new LodashModuleReplacementPlugin());

      config.module.rule('images')
        .test(/.(png|jpe?g|gif|webp)(?.*)?$/)
        .use('image-webpack-loader')
        .loader('image-webpack-loader')
        .options({
          bypassOnDebug: true
        })
        .end()
        .use('url-loader')
        .loader('file-loader')
        .options({
          name: 'assets/[name].[hash:8].[ext]'
        }).end()
      config.module.rule('svg')
        .test(/.(svg)(?.*)?$/)
        .use('file-loader')
        .loader('file-loader')
        .options({
          name: 'assets/[name].[hash:8].[ext]'
        })
    }
  },
  configureWebpack: config => {
    // config.plugins.push(["equire"]);

    if (process.env.NODE_ENV !== 'development') {
      config.output.filename = 'assets/[name].[hash:8].js'
      config.output.chunkFilename = 'assets/[name].[hash:8].js'
    }
    // 公共代码抽离
    config.optimization = {
      // 分割代码块
      splitChunks: {
        cacheGroups: {
          //公用模块抽离
          common: {
            chunks: 'initial',
            minSize: 0, //大于0个字节
            minChunks: 2, //抽离公共代码时,这个代码块最小被引用的次数
          },
          //第三方库抽离
          vendor: {
            priority: 1, //权重
            test: /node_modules/,
            chunks: 'initial',
            minSize: 0, //大于0个字节
            minChunks: 2, //在分割之前,这个代码块最小应该被引用的次数
          },
        },
      }
    }
    // 开启gzip压缩
    config.plugins.push(
      new CompressionWebpackPlugin(
        {
          filename: info => {
            return `${info.path}.gz${info.query}`
          },
          algorithm: 'gzip',
          threshold: 10240, // 只有大小大于该值的资源会被处理 10240
          test: new RegExp('.(' + ['js'].join('|') + ')$'
          ),
          minRatio: 0.8, // 只有压缩率小于这个值的资源才会被处理
          deleteOriginalAssets: false // 删除原文件
        }
      )
    )
  },
  css: {
    extract: true,
    sourceMap: false,
    loaderOptions: {
      sass: {
      },
    },
  },
}


最近:

vue3.0新特性初体验(二)

http://weixin.qq.com/r/pDt0bBbEJktZrVIP9262 (二维码自动识别)

- END -