webpack4 lodash大小太大

Question

我正在使用React，Redux和Webpack构建一个小应用程序。当我切换到Webpack v.4时，我开始收到有关包大小的警告。我读过关于如何让它变小的文章。我还安装了捆绑包分析器，发现我在node-modules中有很大的寄存器。像往常一样，我只使用一个或两个方法，对每个我更改了所有导入内容的文件使用lodash

import _ from 'loadash'

至

import get from 'lodash/get'

但这并不能帮助我降低捆绑包大小。下面我附上了我的webpack.config.js。我不知道为什么它不能工作。更令人惊讶的是，我的构建命令是webpack --mode production，根据我在webpack 4文档中读到的内容，它应该有一些启用了优化的out of the box。

webpack.config.js

const LodashModuleReplacementPlugin = require('lodash-webpack-plugin');
const BundleAnalyzerPlugin = require('webpack-bundle-analyzer').BundleAnalyzerPlugin;

const webpack = require('webpack');

const path = require('path');

module.exports = {
    entry: {
        app: ['babel-polyfill', './src/index.js']
    },
    output: {
        path: path.resolve(__dirname, './dist'),
        filename: 'bundle.js',
    },
    devServer: {
        contentBase: ".",
        headers: {
            "Access-Control-Allow-Origin": "*"
        },
        inline: true,
        historyApiFallback: true,
        port: 8880
    },
    module: {
        rules: [
            {
                test: /\.js$/,
                exclude: /node_modules/,
                use: [
                    {
                        loader: 'babel-loader',
                        options: {
                            presets: ['es2015', 'react'],
                            plugins: ["transform-class-properties"]
                        }
                    },
                    {
                        loader: 'eslint-loader'
                    }
                ]
            },
            {
                test: /\.(png|jpg|gif|jpeg)$/,
                use: [
                    {
                        loader: 'file-loader',
                        options: {}
                    }
                ]
            },
            {
                test: /^.*\.(css|scss)$/,
                use: [
                    'style-loader',
                    'css-loader?importLoaders=1&modules&localIdentName=[path]___[name]__[local]___[hash:base64:5]',
                    {
                        loader: 'postcss-loader',
                        options: {
                            plugins: () => [
                                require('autoprefixer')({
                                    browsers: ['last 1 version']
                                })
                            ]
                        }
                    },
                    'sass-loader'
                ],
            }
        ]
    },
    plugins: [
        new LodashModuleReplacementPlugin(),
        new BundleAnalyzerPlugin()
    ]
};

依赖项和开发依赖项。

 "dependencies": {
    "babel-runtime": "^6.26.0",
    "classnames": "^2.2.5",
    "clean-webpack-plugin": "^0.1.17",
    "css-loader": "^1.0.0",
    "express": "^4.16.2",
    "file-loader": "^1.1.5",
    "html-webpack-plugin": "^3.2.0",
    "lodash": "^4.17.10",
    "node-sass": "^4.6.0",
    "normalize.css": "^8.0.0",
    "postcss-loader": "^2.0.6",
    "prop-types": "^15.5.10",
    "react": "^16.4.1",
    "react-dom": "^16.4.1",
    "react-icons": "^2.2.5",
    "react-redux": "^5.0.6",
    "react-router": "^4.1.2",
    "react-router-dom": "^4.2.2",
    "react-select": "^1.0.0-rc.10",
    "react-test-renderer": "^16.4.1",
    "react-textfit": "^1.0.1",
    "react-transition-group": "^2.2.1",
    "redux": "^4.0.0",
    "redux-devtools-extension": "^2.13.2",
    "redux-form": "^7.1.0",
    "redux-saga": "^0.16.0",
    "reselect": "^3.0.1",
    "sass-loader": "^7.0.3",
    "style-loader": "^0.21.0",
    "webpack-bundle-analyzer": "^2.13.1"   },   "devDependencies": {
    "autoprefixer": "^9.0.1",
    "axios": "^0.18.0",
    "babel-core": "^6.26.3",
    "babel-eslint": "^8.2.6",
    "babel-jest": "^23.4.0",
    "babel-loader": "^7.1.5",
    "babel-plugin-lodash": "^3.3.4",
    "babel-plugin-transform-class-properties": "^6.24.1",
    "babel-plugin-transform-decorators-legacy": "^1.3.4",
    "babel-plugin-transform-object-rest-spread": "^6.26.0",
    "babel-polyfill": "^6.26.0",
    "babel-preset-env": "^1.7.0",
    "babel-preset-es2015": "^6.24.1",
    "babel-preset-es2017": "^6.24.1",
    "babel-preset-react": "^6.24.1",
    "babel-preset-stage-0": "^6.24.1",
    "enzyme": "^3.2.0",
    "enzyme-adapter-react-15": "^1.0.5",
    "enzyme-to-json": "^3.2.2",
    "eslint": "^5.3.0",
    "eslint-loader": "^2.1.0",
    "eslint-plugin-react": "^7.11.1",
    "extract-text-webpack-plugin": "^3.0.0",
    "hoist-non-react-statics": "^3.0.1",
    "identity-obj-proxy": "^3.0.0",
    "isomorphic-fetch": "^2.2.1",
    "jest": "^23.4.1",
    "jquery": "^3.2.1",
    "lodash-webpack-plugin": "^0.11.5",
    "material-design-icons": "^3.0.1",
    "path": "^0.12.7",
    "prettier": "^1.14.2",
    "transform-runtime": "^0.0.0",
    "uglifyjs-webpack-plugin": "^1.3.0",
    "webpack": "^4.16.5",
    "webpack-cli": "^3.1.0",
    "webpack-dev-server": "^3.1.5",
    "webpack-merge": "^4.1.1"   },

​

​

Answer 1

我建议只导入您需要的部件/函数：

import isEmpty from 'lodash.isempty';

在你的package.json中

"dependencies": {
   ...
   "lodash.foreach": "^4.5.0",
   "lodash.includes": "^4.3.0",
   "lodash.isempty": "^4.4.0",

Answer 2

是的，默认情况下，生产模式会进行缩小，但似乎您没有在配置中定义模式。

要使用生产模式，您必须定义如下模式：

module.exports = {
  ...
  mode: 'production'
  ...
};

或

您需要在cli中传递参数，如下所示：

webpack --mode=production 

您正在--mode和production之间使用缺少的=。另外，如果未提供，默认模式也是生产模式。

此外，可以使用stats进行分析，而不是使用插件进行分析，还有内置的支持，而不是使用插件。

有关详细信息，请参阅：

https://webpack.js.org/configuration/optimization/

https://webpack.js.org/configuration/stats/

Answer 3

即使导入一个函数，Lodash包也很容易变得比您预期的要大得多。例如，仅从lodash导入get()将为您的生产贡献5K，精简包。我创建了一个库，它做了一些简化的假设，以提供许多函数的更小的实现：micro-dash。它的get()实现只贡献了65个字节。检查它，看看它是否适合您。