Nodemon server crashing due to mongoose error

Question

Actually, i am learning Node JS, Mongodb and Express JS. so i was just trying to make a db with Mongodb compass and store some data in it. but when i am trying to run my code then my nodemon server is crashing again and again few minutes after starting the server.

So here is the code of main files -

app.js -

var createError = require('http-errors');
var express = require('express');
var path = require('path');
var cookieParser = require('cookie-parser');
var logger = require('morgan');
const expressession = require('express-session');
const flash = require('connect-flash');

var indexRouter = require('./routes/index');
var usersRouter = require('./routes/users');

var app = express();

// view engine setup
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'ejs');

app.use(expressession({
  resave:false,
  saveUninitialized: false,
  secret: 'secretcode671'
}));

app.use(flash());


// is code ne meri gaand maar li hai 

app.use(logger('dev'));
app.use(express.json());
app.use(express.urlencoded({ extended: false }));
app.use(cookieParser());
app.use(express.static(path.join(__dirname, 'public')));

app.use('/', indexRouter);
app.use('/users', usersRouter);

// catch 404 and forward to error handler
app.use(function(req, res, next) {
  next(createError(404));
});

// error handler
app.use(function(err, req, res, next) {
  // set locals, only providing error in development
  res.locals.message = err.message;
  res.locals.error = req.app.get('env') === 'development' ? err : {};

  // render the error page
  res.status(err.status || 500);
  res.render('error');
});

module.exports = app;

user.js -

const mongoose = require('mongoose');

mongoose.connect("mongodb://127.0.0.1:27017/testing2");

const userschema =  mongoose.Schema({
  username: String,
  nickname: String,
  description: String,

  categories: {
    type: Array,
    default: []
  },
  datecreated: {
    type: Date,
    default: Date.now()
  }
})

module.exports = mongoose.model("user", userschema)

index.js -

const { name } = require('ejs');
var express = require('express');
var router = express.Router();
const usermodel = require('./users')

/* GET home page. */
router.get('/', function(req, res, next) {
  res.render('index', { title: 'Express' });
});

 router.get('/create', async function(res,req){
  let userdata = await usermodel.create({
    username: "shadow",
    nickname: "Teju",
    description: "Hello i am a guy who is learning programming",
  
    categories: ['js','nodejs','react','gsap','express', 'mongodb'],
   
  })
  res.send(userdata);
 })
module.exports = router;

I have wrote this code in order to make a db and store some data in it for my learning and practice purpose. When i run this on localhost:3000 with the "npx nodemon" command so the server gets started and i come on the index file of this website, everything works fine til here. But when i try to go to /create route by this url - "localhost:3000/create" so it keeps loading for a few seconds and then server gets crashed. after server crash i get the following error in my terminal - C:\Users\user\Desktop\Tejashv\Programming files\Practice\myapp\node_modules\mongoose\lib\connection.js:875 err = new ServerSelectionError(); ^

MongooseServerSelectionError: connect ECONNREFUSED 127.0.0.1:27017 at _handleConnectionErrors (C:\Users\user\Desktop\Tejashv\Programming files\Practice\myapp\node_modules\mongoose\lib\connection.js:875:11) at NativeConnection.openUri (C:\Users\user\Desktop\Tejashv\Programming files\Practice\myapp\node_modules\mongoose\lib\connection.js:826:11) { reason: TopologyDescription { type: 'Unknown', servers: Map(1) { '127.0.0.1:27017' => ServerDescription { address: '127.0.0.1:27017', type: 'Unknown', hosts: [], passives: [], arbiters: [], tags: {}, minWireVersion: 0, maxWireVersion: 0, roundTripTime: -1, lastUpdateTime: 56995928, lastWriteDate: 0, error: MongoNetworkError: connect ECONNREFUSED 127.0.0.1:27017 at connectionFailureError (C:\Users\user\Desktop\Tejashv\Programming files\Practice\myapp\node_modules\mongodb\lib\cmap\connect.js:379:20) at Socket. (C:\Users\user\Desktop\Tejashv\Programming files\Practice\myapp\node_modules\mongodb\lib\cmap\connect.js:285:22) at Object.onceWrapper (node:events:629:26) at Socket.emit (node:events:514:28) at emitErrorNT (node:internal/streams/destroy:151:8) at emitErrorCloseNT (node:internal/streams/destroy:116:3) at process.processTicksAndRejections (node:internal/process/task_queues:82:21) { [Symbol(errorLabels)]: Set(1) { 'ResetPool' }, [cause]: Error: connect ECONNREFUSED 127.0.0.1:27017 at TCPConnectWrap.afterConnect [as oncomplete] (node:net:1595:16) { errno: -4078, code: 'ECONNREFUSED', syscall: 'connect', address: '127.0.0.1', port: 27017 } }, topologyVersion: null, setName: null, setVersion: null, electionId: null, logicalSessionTimeoutMinutes: null, primary: null, me: null, '$clusterTime': null } }, stale: false, compatible: true, heartbeatFrequencyMS: 10000, localThresholdMS: 15, setName: null, maxElectionId: null, maxSetVersion: null, commonWireVersion: 0, logicalSessionTimeoutMinutes: null }, code: undefined }

Node.js v20.5.1 [nodemon] app crashed - waiting for file changes before starting...

I even tried to go to Mongodb Compass in order to see if i can do something in this and when i try to connect the database i get the follow error there - connect ECONNREFUSED 127.0.0.1:27017

Can someone please help me by telling what is the cause of this problem and how to solve it. I would be really thankful to you if you can help me

Answer 1

The ECONNREFUSED 127.0.0.1:27017 error indicates that there is no application currently listening on that port and IP.

You are trying to connect to a MongoDB database. Make sure it is installed and running at port 27017