javascript - 如何在 Ionic 中对图像和其他静态 Assets 进行指纹识别以清除缓存？

Question

我在 Ionic v3 中扩展了默认的 webpack 配置以强制清除缓存。

我能够对生成的 JavaScript 工件进行指纹识别，但无法对 Assets 文件夹下的图像和 JSON 文件进行指纹识别。我从 Bundled files and cache-busting 获得了帮助.

webpack config.js 的摘录

module.exports = {
  // ...
  output: {
    filename: '[name].[chunkhash].js',
    chunkFilename: '[name].[chunkhash].js',
  },
  plugins: [
    new WebpackChunkHash({algorithm: 'md5'}) // 'md5' is default value
  ]
}

以上是对 JavaScript 包进行指纹识别的方法，它运行良好。我想在 Assets 文件夹中添加哈希/指纹图像和 JSON 文件。我也对图像使用了相同的方法，但它没有用。

我扩展了 webpack config.js 并添加了一个新的图像规则。默认情况下，webpack 直接将图像和 Assets 复制到输出文件夹。

复制Config.js

module.exports = {
  copyAssets: {
    src: ['{{SRC}}/assets/**/*'],
    dest: '{{WWW}}/assets'
  },
  copyIndexContent: {
    src: ['{{SRC}}/index.html', '{{SRC}}/manifest.json', '{{SRC}}/service-worker.js'],
    dest: '{{WWW}}'
  },
  copyFonts: {
    src: ['{{ROOT}}/node_modules/ionicons/dist/fonts/**/*', '{{ROOT}}/node_modules/ionic-angular/fonts/**/*'],
    dest: '{{WWW}}/assets/fonts'
  },

此处直接复制图像和其他 Assets 。我在扩展的 webpack.config.js 中添加了一条新规则，但构建过程忽略了它。我该如何解决这个问题？

摘自webpack config.js

 {
        test: /\.(png|jpg|gif)$/,
        loader: 'file-loader',
        options: {

            name:'[name].[hash].[ext]',//adding hash for cache busting
            outputPath:'assets/imgs',
            publicPath:'assets/imgs'


        },

整个 Webpack.config.js

/*
 * The webpack config exports an object that has a valid webpack configuration
 * For each environment name. By default, there are two Ionic environments:
 * "dev" and "prod". As such, the webpack.config.js exports a dictionary object
 * with "keys" for "dev" and "prod", where the value is a valid webpack configuration
 * For details on configuring webpack, see their documentation here
 * https://webpack.js.org/configuration/
 */

var path = require('path');
var webpack = require('webpack');
var ionicWebpackFactory = require(process.env.IONIC_WEBPACK_FACTORY);

var ModuleConcatPlugin = require('webpack/lib/optimize/ModuleConcatenationPlugin');
var PurifyPlugin = require('@angular-devkit/build-optimizer').PurifyPlugin;

var optimizedProdLoaders = [
  {
    test: /\.json$/,
    loader: 'json-loader'
  },
  {
    test: /\.js$/,
    loader: [
      {
        loader: process.env.IONIC_CACHE_LOADER
      },

      {
        loader: '@angular-devkit/build-optimizer/webpack-loader',
        options: {
          sourceMap: true
        }
      },
    ]
  },
  {
    test: /\.ts$/,
    loader: [
      {
        loader: process.env.IONIC_CACHE_LOADER
      },

      {
        loader: '@angular-devkit/build-optimizer/webpack-loader',
        options: {
          sourceMap: true
        }
      },
      {
        test: /\.(png|jpg|gif)$/,
        loader: 'file-loader',
        options: {

            name:'[name].[hash].[ext]',
            outputPath:'assets/imgs',
            publicPath:'assets/imgs'
        },
      },


      {
        loader: process.env.IONIC_WEBPACK_LOADER
      }
    ]
  }
];

function getProdLoaders() {
  if (process.env.IONIC_OPTIMIZE_JS === 'true') {
    return optimizedProdLoaders;
  }
  return devConfig.module.loaders;
}

var devConfig = {
  entry: process.env.IONIC_APP_ENTRY_POINT,
  output: {
    path: '{{BUILD}}',
    publicPath: 'build/',
    filename: '[name].js',
    devtoolModuleFilenameTemplate: ionicWebpackFactory.getSourceMapperFunction(),
  },
  devtool: process.env.IONIC_SOURCE_MAP_TYPE,

  resolve: {
    extensions: ['.ts', '.js', '.json'],
    modules: [path.resolve('node_modules')]
  },

  module: {
    loaders: [
      {
        test: /\.json$/,
        loader: 'json-loader'
      },
      {
        test: /\.ts$/,
        loader: process.env.IONIC_WEBPACK_LOADER
      },
      {
      test: /\.(jpg|png)$/,
         use: {
         loader: "file-loader",
         options: {
         name: "[name].[hash].[ext]",
         outputPath:'assets/imgs',
         publicPath:'assets/imgs'

    },
  }},
    ]
  },

  plugins: [
    ionicWebpackFactory.getIonicEnvironmentPlugin(),
    ionicWebpackFactory.getCommonChunksPlugin()
  ],

  // Some libraries import Node.js modules but don't use them in the browser.
  // Tell Webpack to provide empty mocks for them so importing them works.
  node: {
    fs: 'empty',
    net: 'empty',
    tls: 'empty'
  }
};

var prodConfig = {
  entry: process.env.IONIC_APP_ENTRY_POINT,
  output: {
    path: '{{BUILD}}',
    publicPath: 'build/',
    filename: '[name].js',
    devtoolModuleFilenameTemplate: ionicWebpackFactory.getSourceMapperFunction(),
  },
  devtool: process.env.IONIC_SOURCE_MAP_TYPE,

  resolve: {
    extensions: ['.ts', '.js', '.json'],
    modules: [path.resolve('node_modules')]
  },

  module: {
    loaders: getProdLoaders()
  },

  plugins: [
    ionicWebpackFactory.getIonicEnvironmentPlugin(),
    ionicWebpackFactory.getCommonChunksPlugin(),
    new ModuleConcatPlugin(),
    new PurifyPlugin()
  ],

  // Some libraries import Node.js modules but don't use them in the browser.
  // Tell Webpack to provide empty mocks for them so importing them works.
  node: {
    fs: 'empty',
    net: 'empty',
    tls: 'empty'
  }
};


module.exports = {
  dev: devConfig,
  prod: prodConfig
}

Answer 1

使用 Webpack 4 你不需要任何额外的插件或加载器。

它将为您提供命名选项 [contenthash]。

另外，看起来你在测试下嵌套了这个 block :.ts block 。

{
    test: /\.(png|jpg|gif)$/,
    loader: 'file-loader',
    options: {
        name:'[name].[hash].[ext]', // Adding hash for cache busting
        outputPath:'assets/imgs',
        publicPath:'assets/imgs'
    }
}

最终，你可以做这样的事情:

    // Copy static assets over with file-loader
    {
        test: /\.(ico)(\?v=[0-9]\.[0-9]\.[0-9])?$/,
        loader: 'file-loader', options: {name: '[name].[contenthash].[ext]'},
    },
    {
        test: /\.(woff|woff2|eot|ttf|otf)(\?v=[0-9]\.[0-9]\.[0-9])?$/,
        loader: 'file-loader', options: {name: 'fonts/[name].[contenthash].[ext]'},
    },
    {
        test: /\.(jpg|gif|png|svg)(\?v=[0-9]\.[0-9]\.[0-9])?$/,
        loader: 'file-loader', options: {name: 'images/[name].[contenthash].[ext]'},
    }
]

使用 [chunkhash] 而不是 content 应该仍然有效，如果你不使用 webpack4 就这样做，但其他信息请参见 this issue寻求解释。

如需更多帮助，请阅读 long-term caching performance guide from Google以及来自 Webpack 的最新缓存文档.