Webpack Custom Hot Update Strategy

Документация на русском

Webpack plugin that allows you to change the strategy for Hot Module Replacement to receive updated modules when hot: true is enabled.

Installation

npm install --save-dev webpack-custom-hot-update-strategy

In Webpack config file webpack.config.js:

const CustomHotUpdateStrategy = require('webpack-custom-hot-update-strategy');

module.exports = {
    // ... Other Webpack config

    devServer: {
        // ... Other Webpack Dev Server config

        hot: true
    },
    plugins: [
        // ... Other Webpack plugins

        new CustomHotUpdateStrategy()
    ]
};

Configuration

A plugin can take an object with keys update and manifest as an argument:

new CustomHotUpdateStrategy({
    manifest: require('./path_to_implementation'),
    update: require('./path_to_implementation')
});

This plugin contains several options for implementing these functions:

• manifest: require a function template that loads the module update manifest [publicPath][hash].hot-update.json.

  • hotDownloadManifest:

    require('webpack-custom-hot-update-strategy/strategies/manifest/hotDownloadManifest');

    Applies by default, if no key is specified manifest. This function corresponds to the native function Hot Module Replacement.

• update: require a function template which takes an argument chunkId, на его основе specifies the path to the file ([publicPath][chunkId].[hash].hot-update.js) and adds the module script to the page.

  • hotDownloadUpdateChunk:

    require('webpack-custom-hot-update-strategy/strategies/update/hotDownloadUpdateChunk');

    Applies by default, if no key is specified update. This function corresponds to the native function Hot Module Replacement: specifies the path to the updated module, creates a new tag <script>, assigns the path as src and append this tag in head.

  • hotDownloadUpdateChunkFetch:

    require('webpack-custom-hot-update-strategy/strategies/update/hotDownloadUpdateChunkFetch');

    Specifies the path to the updated module, makes a request for it using fetch, creates a new tag <script>, inserts the content received from the query and append this tag in head.

  • hotDownloadUpdateChunkFetchEval:

    require('webpack-custom-hot-update-strategy/strategies/update/hotDownloadUpdateChunkFetchEval');

    Specifies the path to the updated module, makes a request for it using fetch, and executes the content, retrieved from the query with eval().

Your own implementation

To write your own implementation of these functions, you need to follow some rules by which the template will be converted into a working function that will fall into the module wrapper.

• Function wrapper:

  The module should wrap the working functions in an anonymous one, which it returns.

  module.exports = function() {
      // Implementation of the working function
  };

• The names of the main functions and their arguments must be strictly defined.

  • manifest:

    module.exports = function() {
        function hotDownloadManifest(requestTimeout) {
            // Implementation of the working function
        }
    };

  • update:

    module.exports = function() {
        function hotDownloadUpdateChunk(chunkId) {
            // Implementation of the working function
        }
    };

• Since many of the values used in these functions are custom, you must replace them with special $expressions$ in the template, which will be replaced with the desired values at compile time.

List of special expressions:

• $require$ -> __webpack_require__

• $crossOriginLoading$ -> output.crossOriginLoading

• $hotMainFilename$ -> output.hotUpdateMainFilename

• $hotChunkFilename$ -> output.hotUpdateChunkFilename

• $hash$ -> Current module hash

With all of the above in mind, the standard function template for update prop will look like this:

module.exports = function() {
    function hotDownloadUpdateChunk(chunkId) {
        var script = document.createElement('script');
        script.charset = 'utf-8';
        script.src = $require$.p + $hotChunkFilename$;
        if ($crossOriginLoading$) script.crossOrigin = $crossOriginLoading$;
        document.head.appendChild(script);
    }
};