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 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 viewRouter = require('./routes/viewRoutes');
const bookingRouter = require('./routes/bookingRoutes');

const app = express();

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

// GLOBAL MIDDLEWARES

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

// Set security HTTP headers
app.use(
  helmet({
    crossOriginEmbedderPolicy: false,
  })
);

// Further HELMET configuration for Security Policy (CSP)
const scriptSrcUrls = [
  'https://unpkg.com/',
  'https://tile.openstreetmap.org',
  'https://js.stripe.com/',
];
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/',
];
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],
      frameSrc: [
        'self',
        'unsafe-inline',
        'data:',
        'blob:',
        'https://*.stripe.com',
        'https://*.cloudflare.com/',
        'https://bundle.js:*',
        'ws://localhost:*/',
      ],
    },
  })
);

// Development logging
if (process.env.NODE_ENV === 'development') {
  app.use(morgan('dev')); // display the info about the request in the console
}

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

// Body parser, reading data from body into req.body
app.use(
  express.json({
    limit: '10kb', // limit the req body
  })
); // a middleware used to modify body of request
app.use(express.urlencoded({ extended: true, limit: '10kb' }));
app.use(cookieParser());

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

// Data sanitization against XSS
app.use(xss());

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

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

// app.get('/api/v1/tours', getAllTours);
// app.get('/api/v1/tours/:id', getTour);
// app.post('/api/v1/tours', createTour);
// app.patch('/api/v1/tours/:id', updateTour);
// app.delete('/api/v1/tours/:id', deleteTour);

// 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);

// HANDLING UNHANDLED ROUTES
app.all('*', (req, res, next) => {
  next(new AppError(`Can't find ${req.originalUrl} on this server!`, 404)); // this next(err) will skip all the middleware in the stack, then send error to the error handling middleware
});

// GLOBAL ERROR HANDLING MIDDLEWARE
app.use(globalErrorHandler);

module.exports = app;