serve.js updated for automatic server restart on React-Starter-Kit based on https://github.com/kriasoft/react-starter-kit/blob/ebbce5aed8f3efa9315abaec302cd1060d609a95/gulpfile.babel.js#L115-L137

serve.js

/**
 * React Starter Kit (http://www.reactstarterkit.com/)
 *
 * Copyright © 2014-2015 Kriasoft, LLC. All rights reserved.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE.txt file in the root directory of this source tree.
 */

import path from 'path';
import cp from 'child_process';
import gaze from 'gaze';

/**
 * Launches Node.js/Express web server in a separate (forked) process.
 */
export default () => new Promise((resolve, reject) => {
  console.log('serve');
  let started = false;
  let server = (function startup() {
    const child = cp.fork('build/server.js', {
      env: Object.assign({NODE_ENV: 'development'}, process.env)
    });
    child.once('message', message => {
      if (message.match(/^online$/)) {
        if (!started) {
          started = true;
          gaze('./build/server.js', function(err, watcher) {
            this.on('all', (event, filepath) => {
              console.log('Restarting development server.');
              server.kill('SIGTERM');
              server = startup();
            });
          });
          resolve();
        }
      }
    });
    child.once('error', err => reject(error));
    return child;
  })();

  process.on('exit', () => server.kill('SIGTERM'));
});

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