index.js

"use strict";
const express = require('express');
const app = express();
const path = require('path');
const compression = require('compression');


// Production middlewares
const publicPath = '/';
const outputPath = path.resolve(process.cwd(), 'build');

  // compression middleware compresses your server responses which makes them
  // smaller (applies also to assets). You can read more about that technique
  // and other good practices on official Express.js docs http://mxs.is/googmy

  app.use(function(req, res, next) {
    res.header("Access-Control-Allow-Origin", "*");
    res.header("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, Accept");
    next();
  });

  app.use(compression());

  app.use(publicPath, express.static(outputPath));

  app.get('/', (req, res) => res.sendFile(path.resolve(outputPath, 'index.html')));
  app.get('/appcache/manifest.html', (req, res) => {res.sendFile(path.resolve(outputPath, 'appcache/manifest.html'))});
  app.get('/appcache/manifest.appcache', (req, res) => {res.sendFile(path.resolve(outputPath, 'appcache/manifest.appcache/'))});

  app.get('/build/:file', (req, res, next) => {
    let file = req.params.file;
    let filePath = path.resolve(outputPath, file);
    res.sendFile(path.resolve(outputPath, filePath));
  });

  app.get('/:file', (req, res, next) =>  {
    console.log(file);
    let file = req.params.file;
    let filePath = path.resolve(outputPath, file);
    if (file === '/login') {
      res.sendFile(path.resolve(outputPath, 'index.html'));
    }

    res.sendFile(path.resolve(outputPath, 'index.html'));
    return;
  });



  const port = process.env.PORT || 3000;;

  app.listen(port, (err) => {
    if (err) {
      console.log(err);
    }
    console.log(`listening on port ${port}`);
    console.log(outputPath);
  });