webpackDevServer.config.js

'use strict';

const errorOverlayMiddleware = require('react-dev-utils/errorOverlayMiddleware');
const noopServiceWorkerMiddleware = require('react-dev-utils/noopServiceWorkerMiddleware');
const path = require('path');
const config = require('./webpack.config.dev');
const paths = require('./paths');

const protocol = process.env.HTTPS === 'true' ? 'https' : 'http';
const host = process.env.HOST || '0.0.0.0';

module.exports = function(proxy, allowedHost) {
  return {
    disableHostCheck:
      !proxy || process.env.DANGEROUSLY_DISABLE_HOST_CHECK === 'true',
    compress: true,
    clientLogLevel: 'none',
    contentBase: paths.appPublic,
    watchContentBase: true,
    hot: true,
    publicPath: config.output.publicPath,
    quiet: true,
    watchOptions: {
      ignored: new RegExp(
        `^(?!${path
          .normalize(paths.appSrc + '/')
          .replace(/[\\]+/g, '\\\\')}).+[\\\\/]node_modules[\\\\/]`,
        'g'
      ),
    },
    // Enable HTTPS if the HTTPS environment variable is set to 'true'
    https: protocol === 'https',
    host: host,
    overlay: false,
    historyApiFallback: {
      // Paths with dots should still use the history fallback.
      // See https://github.com/facebookincubator/create-react-app/issues/387.
      disableDotRule: true,
    },
    public: allowedHost,
    proxy,
    before(app) {
      // This lets us open files from the runtime error overlay.
      app.use(errorOverlayMiddleware());
      // This service worker file is effectively a 'no-op' that will reset any
      // previous service worker registered for the same host:port combination.
      // We do this in development to avoid hitting the production cache if
      // it used the same host and port.
      // https://github.com/facebookincubator/create-react-app/issues/2272#issuecomment-302832432
      app.use(noopServiceWorkerMiddleware());
    },
  };
};