server.js

(function() {
  'use strict';

  var express = require('express');
  var app = express();
  var http = require('http');
  var server = http.createServer(app);
  var enableSsl = process.env.SIS_ENABLE_SSL || false;
  var shell = require('shelljs');
  var chalk = require('chalk');
  var serveIndex = require('serve-index');
  var Admzip = require('adm-zip');

  /**
   * Make sure we only pass data over https
   */
  var forceSSL = function(req, res, next) {
    if (req.headers['x-forwarded-proto'] !== 'https') {
      return res.redirect(['https://', req.get('Host'), req.url].join(''));
    }
    return next();
  };

  // Force SSL when the option is enabled
  if (enableSsl) {
    app.use(forceSSL);
  }

  // List public for the static assets
  app.use('/dist', serveIndex(__dirname + '/dist', {'icons': true}));

  /**
   * Echo console.log messages in a unified way
   */
  var echo = function(message) {
    shell.echo(chalk.green('Build: ') + message);
  };

  /**
   * Creating the zip file
   * @return {[type]} [description]
   */
  var createZip = function() {
    echo('Creating the zip file');

    var zip = new Admzip();
    zip.addLocalFolder('dist');
    zip.writeZip('dist/files_latest.zip');
  };

  /**
   * The build command
   *   - Fetch the latest code
   *   - Run a gulp build
   *   - Copy the build dir to the public directory
   */
  var build = function() {
    echo('Start ...');

    if (shell.test('-d', 'x-sis-custom')) {
      echo('Repo update');
      shell.cd('x-sis-custom');
      shell.exec('git pull');

      echo('Repo update dependencies');
      shell.exec('npm install');

      echo('Gulp build - Start');
      shell.exec('npm run build');

      echo('Copy dist directory');
      shell.cd('..');
      shell.exec('rm -rf dist');
      shell.exec('cp -Rv x-sis-custom/dist dist');

      createZip();

      app.use('/dist', express.static(__dirname + '/dist'));
    } else {
      echo(chalk.red('Initial fetch step is still happening'));
    }
  };

  var buildResponse = function(req, res) {
    res.json({
      'status': 'building'
    });
    build();
  };

  // Will fire the build command
  app.get('/api/build', buildResponse);
  app.post('/api/build', buildResponse);

  // Listen to a ping request
  // We use this for uptimerobot
  app.get('/api/ping', function(req, res) {
    res.json({
      'status': 'ok'
    });
  });

  var fetch = function() {
    if (!shell.test('-d', 'x-sis-custom') && !shell.test('-d', 'z-sis-custom')) {
      echo('Fetch - Repo clone - Start');
      shell.exec('git clone --depth 1 https://github.com/ucberkeley/sis-custom.git z-sis-custom');

      echo('Fetch - Install packages');
      shell.cd('z-sis-custom');
      shell.exec('npm install');
      echo('Fetch - Packages installed');
      shell.cd('..');
      shell.mv('z-sis-custom', 'x-sis-custom');
      build();
    }
  };

  var port = process.env.PORT || 5000;
  server.listen(port);
  server.on('listening', function() {
    console.log('Express server started on port %s at %s', server.address().port, server.address().address);

    // Clean up previous directories
    shell.exec('rm -r dist x-sis-custom z-sis-custom');

    // Initial Fetch
    fetch();
  });
})();