app.js

const path = require('path');
const express = require('express');
//const fs = require('fs');

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 bookingController = require('./controllers/bookingController');

const app = express();

// helps with Heroku deployment - sets a header that we can check when we send a
// secure cookie in Heroku.
app.enable('set proxy');

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

// 1) GLOBAL MIDDLEWARE
// Implement CORS
app.use(cors());
// This sets the header 'Access-Control-Allow-Origin' to '*'

// We could also restrict cors to only selected domains, e.g.
// API served on api.natours.com, front-end on natours.com
// app.use(cors({
//   origin: 'https://www.natours.com'
// }))

// For non-simple http requests (patch, put and delete), the browser issues a
// pre-flight phase and sends an options request (another method like get or
// patch) and if it receives the 'Access-Control-Allow-Origin' header, then it
// knows it is safe to continue the request.
app.options('*', cors());

// We could also only allow to access a certain route from other domains.
// app.options('/api/v1/tours/:id', cors());

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

// Set security HTTP headers
app.use(helmet());

// Fixes content security policy that prevented Mapbox CDN from loading.
app.use(
  helmet.contentSecurityPolicy({
    directives: {
      defaultSrc: ["'self'", 'https:', 'http:', 'data:', 'ws:'],
      baseUri: ["'self'"],
      fontSrc: ["'self'", 'https:', 'http:', 'data:'],
      scriptSrc: ["'self'", 'https:', 'http:', 'blob:'],
      styleSrc: ["'self'", "'unsafe-inline'", 'https:', 'http:'],
    },
  })
);

// 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, // one hour
  message: 'Too many requests from this IP, please try again in an hour',
});
app.use('/api', limiter);

// Before using the body parser, the body is a stream and not json yet. This is
// what Stripe excepts, so we need to call it now.
app.post(
  '/webhook-checkout',
  express.raw({ type: 'application/json' }),
  bookingController.webhookCheckout
);

// Body parser, reading data from body into req.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 against XSS

app.use(xss());

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

app.use(compression());

// app.use((req, res, next) => {
//   console.log('Hello from the middleware ⏳');
//   next();
// });

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

// 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);

// Special route to handle all pages not found on the server
app.all('*', (req, res, next) => {
  // res.status(404).json({
  //   status: 'fail',
  //   message: `Can't find ${req.originalUrl} on this server`,
  // });

  // const err = new Error(`Can't find ${req.originalUrl} on this server`);
  // err.status = 'fail';
  // err.statusCode = 404;

  // next(err);
  next(new AppError(`Can't find ${req.originalUrl} on this server`, 404));
});

// Here we define the error handling middleware function that is called whenever
// we write next(newAppError()) - it is defined after all functions preceding it
// in the middleware path.
app.use(globalErrorHandler);

// 4) START SERVER

module.exports = app;