1. 使用 gzip 压缩打包后的 js 文件
这个方法优化浏览器下载时的文件大小（打包后的文件大小没有改变）
webpack.config.prod.js 中
var CompressionWebpackPlugin = require(‘compression-webpack-plugin‘);
// 在 pligins 中添加
new CompressionWebpackPlugin({ //gzip 压缩
asset: ‘\[path\].gz\[query\]‘,
algorithm: ‘gzip‘,
test: new RegExp(
‘\\\.(js|css)$‘ //压缩 js 与 css
),
threshold: 10240,
minRatio: 0.8
})这样打包出的 css js，会有 css.gz js.gz，即压缩过的 js 和 css。
之后在服务器端的 nginx 配置中开启 gzip：
查看配置文件：vim /usr/local/etc/nginx/nginx.conf
// 写在 http 中就可以
gzip on;
gzip_types application/javascript text/css image/jpeg;这样浏览器下载文件时还是之前的 js，但是服务器返回的压缩过的 .gz 文件，再在本地解压，时间缩短了很多。
2. echart 使用外链 js 文件，不引入 npm 包
在 html 中引入 echarts.min.js，china.js，echarts-gl.min.js，echarts-wordcloud.min.js，不引入 npm 包
在 webpack生产打包配置中增加：
externals: {
"react": "React", // 左边引入时的自定义名字，右边全局变量名
"react-dom": "ReactDOM",
"jquery": "jQuery",
"echarts": "echarts"
}https://doc.webpack-china.org/configuration/externals/#externals
打包后文件大小减小 0.5M
3. 配置打包去掉注释，删除debugger，删除console
new webpack.optimize.UglifyJsPlugin({
comments: false, //去掉注释
compress: {
warnings: false,
drop_debugger: true,
drop_console: true
}
}),4. ant design 按需引入
https://github.com/ant-design/ant-design/issues/2656
- 可以直接写，缺点每个组件需要单写一行
import Button from "antd/lib/button" - 用对象的方式写
import { Button } from ‘antd‘;如果单用这种方式写，打包的时候每个文件会把 antd 的所有模块都加载进去，参见：
https://ant.design/docs/react/getting-started-cn#%E6%8C%89%E9%9C%80%E5%8A%A0%E8%BD%BD
需要引入 babel-plugin-import 使每个模块按需加载，并在 webpack.config.js 里配置
loaders: [ ... { text: /\.(js|jsx)$/, include: paths.appSrc, loader: ‘babel‘, query: { cacheDirectory: true, plugins: [["import", { libraryName: "antd", style: "css" }]] // 这一句 } }, ... ]每个引入antd的文件减小0.5M
5. 删除无用依赖
6. echart 图表懒加载
https://www.npmjs.com/package/react-lazyload
import LazyLoad from ‘react-lazyload‘;
// 在需要懒加载的元素外包裹
<LazyLoad height={300} offset={10}><!--元素--></LazyLoad>7. 使用 webpack-parallel-uglify-plugin 替代 UglifyJS 插件
使用 webpack-parallel-uglify-plugin 替代 webpack.optimize.UglifyJsPlugin 并行混淆压缩 js 文件，打包时间从四分钟减到两分钟。用法和 UglifyJsPlugin 相同。
var ParallelUglifyPlugin=require(‘webpack-parallel-uglify-plugin‘) ;
new ParallelUglifyPlugin({
uglifyJS: {
output: {
comments: false //去掉注释
},
compress: {
warnings: false,
drop_debugger: true,
drop_console: true
}
}
}),8. happypack 多进程执行 loader
引入 happypack
module.exports = {
module: {
loaders: [
{
test: /.jsx?$/,
loader: "happypack/loader?id=happybabel",
exclude: /node_modules/
},
{
test: /\.json$/,
exclude: /node_modules/,
loader: ‘happypack/loader?id=happyjson‘,
include: [
path.join(rootPath, "src/components"),
path.join(rootPath, "src/mockdata"),
path.join(rootPath, "src/views"),
]
},
{
test: /\.less$/,
loader: ExtractTextPlugin.extract("style", "happypack/loader?id=happyless"),
include: [
path.join(rootPath, "src/components/"),
path.join(rootPath, "src/assets"),
path.join(rootPath, "node_modules/antd"),
]
},
]
},
plugins: [
createHappyPlugin(‘happybabel‘, [{
loader: ‘babel-loader‘,
query: {
cacheDirectory: true,
plugins: [
["import", { "libraryName": "antd", "style": true }] // `style: true` 会加载 less 文件
]
},
}]),
createHappyPlugin(‘happyjson‘, [‘json-loader‘]),
createHappyPlugin(‘happyless‘, [‘css-loader?sourceMap!less‘]),
]
}
function createHappyPlugin(id, loaders) {
return new HappyPack({
id: id,
loaders: loaders,
threadPool: happyThreadPool,
verbose: true
});
}打包时间减少了 15s
9. 检查 loader 中的 include 和 exclude 使其更加精确
{
test: /\.json$/,
exclude: /node_modules/,
loader: ‘happypack/loader?id=happyjson‘,
include: [
path.join(rootPath, "src/components"),
path.join(rootPath, "src/mockdata"),
path.join(rootPath, "src/views"),
]
},
{
test: /\.less$/,
loader: ExtractTextPlugin.extract("style", "happypack/loader?id=happyless"),
include: [
path.join(rootPath, "src/components/"),
path.join(rootPath, "src/assets"),
path.join(rootPath, "node_modules/antd"),
]
},搜索文件范围变窄，可以减小一点打包时间。
原文地址：https://www.cnblogs.com/ubuntugx/p/8794582.html