server.js

const path = require('path');
const express = require('express');
const dotenv = require('dotenv');
const morgan = require('morgan');
const colors = require('colors');
const fileUpload = require('express-fileupload');
const mongoSanitize = require('express-mongo-sanitize');
const helmet = require('helmet');
const xss = require('xss-clean');
const rateLimit = require('express-rate-limit');
const hpp = require('hpp');
const cors = require('cors');
const cookieParser = require('cookie-parser');
const connectDB = require('./config/db');
const errorHandler = require('./middleware/error');

//Load env vars
dotenv.config({ path: './config/config.env' });

//Connect to the database
connectDB();

//Router files
const bootcamps = require('./routes/bootcamps');
const courses = require('./routes/courses');
const auth = require('./routes/auth');
const users = require('./routes/users');
const reviews = require('./routes/reviews');

const app = express();

//body parser
app.use(express.json());

//cookie parser
app.use(cookieParser());

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

//file uploading
app.use(fileUpload());

//sanitize data
app.use(mongoSanitize());

//set security headers
app.use(helmet());

//prevent xss attacks
app.use(xss());

//rate limit for api request
const limiter = rateLimit({
  windowMs: 10 * 60 * 1000, //10 min
  max: 100, //limit each ip to 100 request per windowMs
});

//apply to all request
app.use(limiter);

//prevent http params pollution
app.use(hpp());

//enable cross-origin resource sharing
app.use(cors());

//set static folder
app.use(express.static(path.join(__dirname, 'public')));

//Mount Routers
app.use('/api/v1/bootcamps', bootcamps);
app.use('/api/v1/courses', courses);
app.use('/api/v1/auth', auth);
app.use('/api/v1/users', users);
app.use('/api/v1/reviews', reviews);

app.use(errorHandler);

const PORT = process.env.PORT || 5000;

const server = app.listen(
  PORT,
  console.log(
    `Server running in ${process.env.NODE_ENV} mode on port ${PORT}`.yellow.bold
  )
);

//handle unhandled promise rejections
process.on('unhandledRejection', (err, promise) => {
  console.log(`Error: ${err.message}`.red);

  //close server and exit process
  server.close(() => process.exit(1));
});