app.js

require("dotenv").config();

const mongoose = require('mongoose');
const createError = require('http-errors');
const logger = require('morgan');
const express = require('express');
const jwt = require('jsonwebtoken');
const cors = require('cors');

require('./config/db.config');

const app = express();

// Middlewares

app.use(cors());
app.use(express.json());
app.use(logger('dev'));

// Routes

const routes = require('./config/routes');
app.use('/', routes);

// Errors

app.use((req, res, next) => {
  next(createError(404, "Route not found"));
});

app.use((error, req, res, next) => {
  if (error instanceof mongoose.Error.ValidationError) {
    error = createError(400, error);
  } else if (error instanceof mongoose.Error.CastError) {
    error = createError(404, "Sorry, not found");
  } else if (error.message.includes("E11000")) {
    error = createError(400, "Already exists");
  } else if (error instanceof jwt.JsonWebTokenError) {
    error = createError(401, error);
  } else if (!error.status) {
    error = createError(500, error);
  }
  if (error.status >= 500) {
    console.log(error);
  }

  const data = {};
  data.message = error.message;
  data.errors = error.errors
    ? Object.keys(error.errors).reduce(
        (errors, key) => ({
          ...errors,
          [key]: error.errors[key].message || error.errors[key],
        }),
        {}
      )
    : undefined;

  res.status(error.status).json(data);
});

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

app.listen(port, () => {
  console.log(`Yeah! Listening on port ${port}`);
});