server.js

// Import NPM/Node Packages
const path = require("path");
const express = require("express");
const dotenv = require("dotenv");
const fileupload = require("express-fileupload");
const cookieParser = require("cookie-parser");
const mongoSanitize = require("express-mongo-sanitize");
const helmet = require("helmet");
const xssClean = require("xss-clean");
const rateLimit = require("express-rate-limit");
const hpp = require("hpp");
const cors = require("cors");

// Import Local Files
const connectDB = require("./config/connectdb");
const errorHandler = require("./middleware/errorhandler");

// Load dotenv variables
dotenv.config({ path: "./config/config.env" });

// Express config
const app = express();
const PORT = process.env.PORT || 3000;

app.use(express.json());

// Cors config
const corsoptions = {
  origin: 'http://localhost:3000',
  credentials: true,
  'Access-Control-Allow-Headers': ['Content-Type', 'Authorization']
}
// Allow Cors
app.use(cors(corsoptions));

// Cookie Parser
app.use(cookieParser());

// connect to db
connectDB();

// File Uploading
app.use(fileupload());

// Sanitize input
app.use(mongoSanitize());

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

// Prevent XSS attacks
app.use(xssClean());

// Rate Limiter
const limiter = rateLimit({
  windowMs: process.env.RATE_LIMIT_MINUTES * 60 * 1000,
  max: process.env.RATE_LIMIT_REQUESTS,
  message: `Too many requests. You are only allowed ${process.env.RATE_LIMIT_REQUESTS} requests per ${process.env.RATE_LIMIT_MINUTES} minutes`,
});
app.use(limiter);

// Prevent http param pollution
app.use(hpp());

// Set Static folder
app.use(express.static(path.join(__dirname, "public")));

// Import Routes
const artistsRoutes = require("./routes/artist");
const songRoutes = require("./routes/songs");
const authRoutes = require("./routes/auth");
const userRoutes = require("./routes/users");
const reviewRoutes = require("./routes/reviews");

// Use Routes
app.use("/api/v1/artists", artistsRoutes);
app.use("/api/v1/songs", songRoutes);
app.use("/api/v1/auth", authRoutes);
app.use("/api/v1/users", userRoutes);
app.use("/api/v1/reviews", reviewRoutes);

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

// Error Handler Usage - LAST ONLY
app.use(errorHandler);

// Handle unhandled promise rejections
process.on("unhandledRejection", (err, promise) => {
  //  Log problem to console
  console.log(`Unhandled Promise Rejection: ${err.message}`);
  // Stop Server and the process
  server.close(() => {
    process.exit(1);
  });
});