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('trust proxy', 3);

app.set('view engine', 'pug');
app.set('views', path.join(__dirname, 'views'));

// 1. Global Middlewares
// Implement CORS
app.use(cors());

app.options('*', cors());

// Serving static files
app.use(express.static(path.join(__dirname, 'public')));

// Set security Http Headers
app.use(
  helmet({
    contentSecurityPolicy: {
      directives: {
        // ... other directives

        'script-src': [
          "'self'", // allow scripts from your own domain
          "'unsafe-inline'", // allow inline scripts (you may want to remove this depending on your needs)
          '*', // allow scripts from anywhere
        ],
        'worker-src': [
          "'self'", // allow web workers from your own domain
          '*', // allow web workers from anywhere
          'blob:', // allow web workers from blob URLs
        ],
        'connect-src': [
          "'self'", // allow connections to your own domain
          '*', // allow connections to anywhere
        ],
      },
    },
  }),
);

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

// Limit requests from same API
const limiter = rateLimit({
  max: 100,
  windowMs: 60 * 60 * 1000,
  message: 'Too many requests from this IP, please try again in an hour',
});
app.use('/api', limiter);

// Body Parser, reading data from the body
app.use(express.json({ limit: '10kb' }));
app.use(express.urlencoded({ extended: true, limit: '10kb' }));
app.use(cookieParser());

// Data sanitization against NOSQL query injection
app.use(mongoSanitize());

// Data sanitization again XSS attacks
app.use(xss());

// Prevent parameter polution
app.use(
  hpp({
    whitelist: [
      'duration',
      'ratingsQuantity',
      'ratingsAverage',
      'maxGroupSize',
      'difficulty',
      'price',
    ],
  }),
);

app.use(compression());

// Test middleware
app.use((req, res, next) => {
  req.requestTime = new Date().toISOString();
  // console.log(req.cookies);
  next();
});

// 2. Route handlers
// Exported to router files
// app.get('/api/v1/tours', getAllTours);
// app.post('/api/v1/tours', createTour);
// app.get('/api/v1/tours/:id', getTour);
// app.patch('/api/v1/tours/:id', updateTour);
// app.delete('/api/v1/tours/:id', deleteTour);

// 3. 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);

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

app.use(globalErrorHandler);

// 4. Start the server
module.exports = app;