node-hot-loader/loader.js

Hot module replacement for Node.js applications

"use strict";

exports.__esModule = true;
exports.loadWebpack = loadWebpack;
exports.tweakWebpackConfig = tweakWebpackConfig;
var _webpack = _interopRequireDefault(require("webpack"));
function _interopRequireDefault(e) { return e && e.__esModule ? e : { default: e }; }
function handleFunction(options) {
  if (typeof options === 'function') {
    return options();
  }
  return options;
}
function handleWebpackConfig(webpackConfig) {
  return Array.isArray(webpackConfig) ? webpackConfig.map(handleFunction).find(c => c.target === 'node') : handleFunction(webpackConfig);
}

/**
 * Add hmrClient to all entries.
 * @param {import('webpack').Configuration} webpackConfig
 * @returns {import('webpack').Configuration}
 */
function tweakWebpackConfig(webpackConfig) {
  const config = handleWebpackConfig(webpackConfig);
  if (!config) {
    throw new Error('Not found webpack configuration. For multiple configurations in single file you must provide config with target "node".');
  }
  const hmrClientEntry = require.resolve('./HmrClient');
  const addHmrClientEntry = (entry, entryOwner) => {
    const owner = entryOwner;
    if (Array.isArray(owner[entry])) {
      owner[entry].splice(-1, 0, hmrClientEntry);
    } else if (typeof owner[entry] === 'string') {
      owner[entry] = [hmrClientEntry, owner[entry]];
    } else if (typeof owner[entry] === 'function') {
      // Call function and try again with function result.
      owner[entry] = owner[entry]();
      addHmrClientEntry(entry, owner);
    } else if (typeof owner[entry] === 'object') {
      Object.getOwnPropertyNames(owner[entry]).forEach(name => addHmrClientEntry(name, owner[entry]));
    }
  };

  // Add HmrClient to every entries.
  addHmrClientEntry('entry', config);
  if (!config.plugins) {
    config.plugins = [];
  }

  // Add source-map support if configured.
  if (config.devtool && config.devtool.indexOf('source-map') >= 0) {
    config.plugins.push(new _webpack.default.BannerPlugin({
      banner: `;require('${require.resolve('source-map-support').replace(/\\/g, '/')}').install();`,
      raw: true,
      entryOnly: false
    }));
  }

  // Enable HMR globally if not.
  if (!config.plugins.find(p => p instanceof _webpack.default.HotModuleReplacementPlugin)) {
    config.plugins.push(new _webpack.default.HotModuleReplacementPlugin());
  }
  return config;
}

/**
 * Add compiler hooks and start watching (through compiler) for changes.
 * @returns {Promise.<HmrServer>}
 */
function hooks(compiler, options) {
  return Promise.resolve().then(() => require('./HmrServer')).then(({
    default: HmrServer
  }) => new HmrServer({
    ...options,
    compiler // webpack compiler
  }).run());
}

/**
 * @param {{ fork: boolean | string; inMemory: boolean; babel: boolean; logLevel: string; }} options
 */
function loadWebpack(options) {
  Promise.resolve().then(() => {
    if (options.babel) {
      require('@babel/register')({
        extensions: ['.es6', '.es', '.jsx', '.js', '.mjs', '.ts', '.tsx']
      });
    }
  }).then(() => require(`${options.config}`)).then(configModule => tweakWebpackConfig(configModule.default || configModule)).then(webpackConfig => (0, _webpack.default)(webpackConfig)).then(compiler => hooks(compiler, options)).catch(err => console.error(err));
}