app.js

const path = require('path');
const express = require('express');
const morgan = require('morgan');
const rateLimit = require('express-rate-limit');
const helmet = require('helmet');
const mongoSanitize = require('express-mongo-sanitize');
const xss = require('xss-clean');
const hpp = require('hpp');
const cookieParser = require('cookie-parser');
const compression = require('compression');
const cors = require('cors');

const AppError = require('./utils/appError');
const globalErrorHandler = require('./controllers/errorController');
const tourRouter = require('./routes/tourRoutes');
const userRouter = require('./routes/userRoutes');
const reviewRouter = require('./routes/reviewRoutes');
const bookingRouter = require('./routes/bookingRoutes');
const viewRouter = require('./routes/viewRoutes');

const app = express();

app.set('view engine', 'pug');
app.set('views', path.join(__dirname, 'views'));
app.use(express.static(path.join(__dirname, 'public')));

// MIDDLEWARE
if (process.env.NODE_ENV === 'development') {
  app.use(morgan('dev'));
}

// app.use(helmet());

// Further HELMET configuration for Security Policy (CSP)
// const scriptSrcUrls = ['https://unpkg.com/', 'https://tile.openstreetmap.org'];
// const styleSrcUrls = [
//   'https://unpkg.com/',
//   'https://tile.openstreetmap.org',
//   'https://fonts.googleapis.com/',
// ];
// const connectSrcUrls = [
//   'https://unpkg.com',
//   'https://tile.openstreetmap.org',
//   'https://*.stripe.com',
//   'https://bundle.js:*',
//   'ws://127.0.0.1:*/',
// ];
// const fontSrcUrls = ['fonts.googleapis.com', 'fonts.gstatic.com'];

// app.use(
//   helmet.contentSecurityPolicy({
//     directives: {
//       defaultSrc: [],
//       connectSrc: ["'self'", ...connectSrcUrls],
//       scriptSrc: ["'self'", ...scriptSrcUrls],
//       styleSrc: ["'self'", "'unsafe-inline'", ...styleSrcUrls],
//       workerSrc: ["'self'", 'blob:'],
//       objectSrc: [],
//       imgSrc: ["'self'", 'blob:', 'data:', 'https:'],
//       fontSrc: ["'self'", ...fontSrcUrls],
//     },
//   })
// );
// ---------------
const limiter = rateLimit({
  max: 100,
  windowMs: 60 * 60 * 1000,
  message: 'Too many request from this IP, please try again in an hour!',
});
app.use('/api', limiter);

app.use(express.json({ limit: '10kb' }));
app.use(express.urlencoded({ extended: true, limit: '10kb' }));
app.use(cookieParser());
app.use(mongoSanitize());
app.use(xss());
app.use(
  hpp({
    whitelist: [
      'duration',
      'ratingsQuantity',
      'ratingsAverage',
      'maxGroupSize',
      'difficulty',
      'price',
    ],
  })
);
app.use(compression());
app.use(cors());
// Access-Control-Allow-Origin *
app.options('*', cors());

// ROUTES
app.use('/', viewRouter);
app.use('/api/v1/tours', tourRouter);
app.use('/api/v1/users', userRouter);
app.use('/api/v1/reviews', reviewRouter);
app.use('/api/v1/bookings', bookingRouter);

// Handle 404 pages
app.all('*', (req, res, next) => {
  next(new AppError(`Can't find ${req.originalUrl} on this server`, 404));
});

// Global error handler middleware
app.use(globalErrorHandler);

module.exports = app;