index.js

const express = require('express');
const app = express();
const mongoose = require('mongoose');
const Schema = mongoose.Schema;
const url =
  process.env.MONGODB ||
  'mongodb://localhost:27017/apiDB';
const port = process.env.PORT || 8080;

const noteSchema = new Schema({
  text: String,
  priority: String,
  createdAt: Date,
  updatedAt: Date,
});

noteSchema.virtual('id').get(function () {
  return this._id.toHexString();
});

noteSchema.set('toJSON', {
  virtuals: true,
});

const Note = mongoose.model('Note', noteSchema);

mongoose.connect(url, { useNewUrlParser: true, useUnifiedTopology: true });
var db = mongoose.connection;
db.on('error', console.error.bind(console, 'connection error:'));
db.once('open', function () {
  console.log('MONGODB CONNECTED');
});

app.use(express.static('build'));
app.use(express.json());

app.post('/notes', function (req, res) {
  const note = new Note(req.body);
  note.save().then((doc) => {
    res.json(doc);
  });
});

app.get('/notes', function (req, res) {
  Note.find({})
    .sort({ updatedAt: 'desc' })
    .then((docs) => {
      res.json(docs);
    });
});

app.put('/notes/:id', function (req, res) {
  Note.findOneAndReplace({ _id: req.params.id }, req.body, {
    returnDocument: 'after',
  }).then((doc) => {
    res.json(doc);
  });
});

app.delete('/notes/:id', function (req, res) {
  Note.findByIdAndDelete({ _id: req.params.id }).then((doc) => {
    res.json(doc);
  });
});

app.listen(port, function () {
  console.log('server started at :', port);
//   console.log('mongo URL',url);
});