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 session = require('express-session');
const redis = require('redis');
let RedisStore = require('connect-redis')(session);
const config = require('./config/globalConfig');

const AppError = require('./utils/appError');
const globalErrorHandler = require('./controllers/errorController');
const userRouter = require('./routes/userRoutes');
const rbacRouter = require('./routes/policyRoutes');

// Start express app
const app = express();

app.set('trust proxy', ip => {
  if (ip === '127.0.0.1' || ip === '::ffff:172.24.0.5') return true;
  else return false;
});

// 1) GLOBAL MIDDLEWARES
// Implement CORS
app.use(cors());
// Access-Control-Allow-Origin *
// api.yourDomain.com, front-end yourDomain.com
// app.use(cors({
//   origin: 'https://www.yourDomain.com'
// }))

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

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

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

// 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 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 parameter pollution
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();
});

//REDIS
let redisClient = redis.createClient({
  host: config.REDIS_URL,
  port: config.REDIS_PORT,
});
app.use(
  session({
    store: new RedisStore({ client: redisClient }),
    secret: config.SESSION_SECRET,
    resave: false,
    saveUninitialized: false,
    cookie: {
      secure: false,
      httpOnly: true,
      maxAge: 1000 * 60,
    },
  })
);

// 3) ROUTES
app.use('/api/v1/users', userRouter);
app.use('/api/v1/rbac', rbacRouter);

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

app.use(globalErrorHandler);

module.exports = app;