02. 不同的打包模式

两种配置模式：

（1）webpack.dev.js
（2）webpack.pro.js

一、开发环境配置

const { resolve } = require('path');
const autoprefixer = require('autoprefixer');
const HtmlWebpackPlugin = require('html-webpack-plugin');
const { CleanWebpackPlugin } = require('clean-webpack-plugin');
module.exports = {
  entry: './main.js',
  output: {
    filename: 'boundle.js',
    path: resolve(__dirname, 'dist')
  },
  module: {
    rules: [
      {
        test: /\.vue$/,
        loader: 'vue-loader'
      },
      {
        test: /\.js$/,
        use: {
          // webpack 和 babel之间的桥梁
          loader: 'babel-loader'
        },
        // 不编译nodule_modules模块中的代码
        exclude: /node_modules/
      },
      {
        test: /\.css$/,
        loader: [
          'style-loader',
          'css-loader',
          {
            loader: 'postcss-loader',
            options: {
              postcssOptions: {
                plugins: [autoprefixer]
              }
            }
          }
        ]
      },
      {
        // 处理图片
        test: /\.(png|jpg|gif)$/i,
        use: [
          {
            loader: 'url-loader',
            options: {
              name: '[name].[ext]',
              outputPath: 'imgs/',
              limit: 8192
            }
          }
        ]
      },
      {
        test: /\.scss$/,
        loader: [
          'style-loader',
          'css-loader',
          {
            loader: 'postcss-loader',
            options: {
              postcssOptions: {
                plugins: [autoprefixer]
              }
            }
          },
          'sass-loader'
        ]
      },
      // 处理字体图标文件
      {
        test: /\.(eot|svg|ttf|woff)/,
        use: {
          loader: 'file-loader',
          options: {
            outputPath: 'fonts/'
          }
        }
      }
    ]
  },
  plugins: [
    new HtmlWebpackPlugin({
      template: resolve(__dirname, './src/index.html')
    }),
    new CleanWebpackPlugin()
  ]
};

const webpack = require('webpack');
const { merge } = require('webpack-merge'),
  commBase = require('./webpack.base');

const webpack_dev = {
  mode: 'development',
  devServer: {
    contentBase: './dist',
    open: true,
    // 开启热更新
    hot: true,
    port: '3000'
  },
  // 开启tree shaking
  optimization: {
    usedExports: true
  },
  devtool: 'cheap-module-eval-source-map',
  plugins: [new webpack.HotModuleReplacementPlugin()]
};

module.exports = merge(webpack_dev, commBase);

二、生产环境配置

const { merge } = require('webpack-merge');
const commBase = require('./webpack.base');

const webpack_prod = {
  mode: 'production',
  // 开启tree shaking
  devtool: 'cheap-module-source-map'
};

module.exports = merge(webpack_prod, commBase);

三、配置命令

3.1 配置公共文件：

开发环境 和 生产环境 一样的配置文件将其中的内容提取出来

3.1.1 webpack-merge

npm i webpack-merge -D
可以合并两个默认的webpack配置，具体查看github的用法

开发环境的配置信息
公共的配置