工程化: webpack介绍和基础用法

一、介绍

webpack是现代JavaScript应用程序的静态模块打包器

二、命令行

1、安装命令：

npm install webapck -g: 全局安装webapck环境

npm install webapck-cli -g: 全局安装webpack-cli环境

webpack -v: 测试webpack安装成功，显示webpack安装的版本

webpack-cli -v: 测试webpack-cli安装成功，显示webpack-cli安装的版本

webpack --watch: 监听打包命令，每次更新文件自动打包

三、webpack.config.js配置文件

1、entry: 入口文件，指定webpack用哪个文件作为项目的入口

2、output: 输出，指定webpack把处理完成的文件放置到指定路径

3、module: 模块，用于处理各种类型的文件

4、plugins: 插件，如：热更新、代码重用等

5、resolve: 设置路径指向

6、watch: 监听，用于设置文件改动后直接打包

javascript 复制代码

module.exports = {
  context: path.resolve(__dirname, '../'),
  entry: {
    app: './src/main.js'
  },
  output: {
    path: config.build.assetsRoot,
    filename: '[name].js',
    publicPath: process.env.NODE_ENV === 'production'
      ? config.build.assetsPublicPath
      : config.dev.assetsPublicPath
  },
  resolve: {
    extensions: ['.js', '.vue', '.json'],
    alias: {
      'vue$': 'vue/dist/vue.esm.js',
      '@': resolve('src'),
    }
  },
  module: {
    rules: [
      {
        test: /\.vue$/,
        loader: 'vue-loader',
        options: vueLoaderConfig
      },
      {
        test: /\.js$/,
        loader: 'babel-loader',
        include: [resolve('src'), resolve('test'), resolve('node_modules/webpack-dev-server/client')]
      },
      {
        test: /\.(png|jpe?g|gif|svg)(\?.*)?$/,
        loader: 'url-loader',
        options: {
          limit: 10000,
          name: utils.assetsPath('img/[name].[hash:7].[ext]')
        }
      },
      {
        test: /\.(mp4|webm|ogg|mp3|wav|flac|aac)(\?.*)?$/,
        loader: 'url-loader',
        options: {
          limit: 10000,
          name: utils.assetsPath('media/[name].[hash:7].[ext]')
        }
      },
      {
        test: /\.(woff2?|eot|ttf|otf)(\?.*)?$/,
        loader: 'url-loader',
        options: {
          limit: 10000,
          name: utils.assetsPath('fonts/[name].[hash:7].[ext]')
        }
      }
    ]
  },
  node: {
    // prevent webpack from injecting useless setImmediate polyfill because Vue
    // source contains it (although only uses it if it's native).
    setImmediate: false,
    // prevent webpack from injecting mocks to Node native modules
    // that does not make sense for the client
    dgram: 'empty',
    fs: 'empty',
    net: 'empty',
    tls: 'empty',
    child_process: 'empty'
  }
}