Can't connect to a MongoDB using Node.js - node.js

Can't connect to a MongoDB using Node.js.
This is my code (mdb.js):
var MongoClient = require('mongodb').MongoClient, format = require('util').format;
MongoClient.connect('mongodb://localhost:3000', function(err,db){
if(err){
throw err;
} else {
console.log("Connected");
}
db.close();
});
node mdb.js prints MongoError:
enter image description here

it worked for me when i changed 'localhost' to 127.0.0.1

First make sure your MongoDB server is running by running mongod in the directory that MongoDB is installed.
Then see what port it is running on ( usually it's 27017 ) . Then update your URL in your code and you're good to go .

Your error explaining itself.
Mongo cant find default db path B:/data/db.
Create this folder or on start up choose another DB directory
mongod --dbpath yourPath(C:\myDb)
Also default mongo port is 27017 so you need to change connection string like this "mongodb://#localhost:27017/dbYouWant"
Hope this helps.

Use this URL mongodb://0.0.0.0:3000

First of all please verify that have you changed your default database port from 27017 to 3000 or not.
If not changed then please try the below code it's working for me
const { MongoClient } = require("MongoDB");
// Connection URL
const url = "mongodb://localhost:27017";
const client = new MongoClient(URL);
// Database Name
const dbName = "myProject";
async function main() {
// Use connect method to connect to the server
await client.connect();
console.log("Connected successfully to server");
const db = client.db(dbName);
const collection = db.collection("documents");
// return "done.";
}
main()
.then(console.log)
.catch(console.error)
.finally(() => client.close());
Also here is I attached a my screenshot with the output
Sample output example

Related

MongodbClient.connect() not working with mongodb locally

I am trying to connect to mongodb server locally at this ip mongodb://127.0.0.1:27017/ yet still no connection to the mongodb server
I have tried using localhost instead of 127.0.0.1 but not change .
const MongoClient = require('mongodb').MongoClient;
const url = 'mongodb://127.0.0.1:27017/';
const dbname = 'conFusion';
console.log("before connect");
MongoClient.connect(url, (err, client) => {
console.log('Connected SuccessFully');
});
I have also run this command Mongod --dbpath=data --bind-ip 127.0.0.1:27017 but no change
Occasionally I would get the timeout error

Can't connect to MongoDB Server

My nodejs app can't connect to MondoDB Server.
I have already allowed all ip addresses (0.0.0.0/0) to connect.
const mongoose = require('mongoose');
const URL = '' //database url
mongoose.connect(URL, {useNewUrlParser: true}).then(db => {
console.log("Connected")
}).catch(err => {
console.log(err)
})
Above code throws "MongooseServerSelectionError: connection timed out" error
U have to provide URL in mongoose something like this
const url = 'mongodb://localhost:27017/myapp'
But before that please verify whether the mongo is running in your system or not.

Cannot connect to mongoDB Atlas using mongoose : { MongoNetworkError: failed to connect to server }

Although I am not the first on Stackoverflow not to be able to connect to mongoDB atlas using mongoose, no one seems to have my specific error:
{ MongoNetworkError: failed to connect to server
[cluster0-shard-00-00-shqnc.mongodb.net:27017] on first connect
[MongoNetworkError: connection 5 to
cluster0-shard-00-00-shqnc.mongodb.net:27017 closed]
Here's how my server is set-up:
Keys.js
module.exports = {
mongoURI:
"mongodb+srv://Ahmed:<MyMongoDBAtlasPWD>#cluster0-shqnc.mongodb.net/test?retryWrites=true&w=majority"
};
Server.js
const express = require("express");
const mongoose = require("mongoose");
const app = express();
// DB Config
const db = require("./config/keys").mongoURI;
// Connect to MongoDB
mongoose
.connect(db, {
useNewUrlParser: true
})
.then(() => {
console.log("MongoDB connected!");
})
.catch(err => {
console.log(err);
});
app.get("/", (req, res) => {
res.send("Hello");
});
//process.env.Port is for Heroku
const port = process.env.Port || 5000;
// `` ES6 Template literal is used so that we can put a variable inside the String
app.listen(port, () => {
console.log(`Server running on port ${port}`);
});
And this is the code suggested by the MongoDB atlas website to be used:
const MongoClient = require('mongodb').MongoClient;
const uri = "mongodb+srv://Ahmed:<password>#cluster0-shqnc.mongodb.net/test?retryWrites=true&w=majority";
const client = new MongoClient(uri, { useNewUrlParser: true });
client.connect(err => {
const collection = client.db("test").collection("devices");
// perform actions on the collection object
client.close();
});
But, since I don't want to use mongoClient but rather mongoose, I am having some trouble and I cannot see why the code doesn't work;
EDIT 1: I have managed to connect using the Shell command(Check-out my answer). However, connecting through the app doesn't work and gives a different error:
{ MongoNetworkError: failed to connect to server
[cluster0-shard-00-01-shqnc.mongodb.net:27017] on first connect
[MongoError: bad auth Authentication failed.]
EDIT 2: I made a stupid mistake. I've forgotten to remove <> from the . All is good now.
The problem is that I was trying to connect using my MongoDB Atlas account password instead of the user password. Yes, those are 2 different things.
1. Click on Database Access
2. Edit the current user and modify the password
3. Use that password to connect to MongoDB Atlas
Make sure you have whitelisted your public IP. You can find that by googling "what is my ip".

connect mongoDb to nodejs on localhost

I'm trying to use mongoDB for my app.
I have 2 databases and use next code to connect:
var express = require("express");
var router = express.Router();
var mongojs = require("mongojs");
//var mongo_db =
//mongojs("mongodb://xxxxx:xxxxx#some_adress/cat_mean_db", ["tasks"]);
var mongo_db = mongojs("mongodb://xxxxx:xxxxx#localhost:3000/cat_db",
["tasks"]);
//get all docs(pages)
router.get("/tasks", function (req, res, next ) {
mongo_db.tasks.find(function (error, tasks) {
if(error)
res.send(error);
res.json(tasks);
});
});
if I use this db
var mongo_db =
mongojs("mongodb://xxxxx:xxxxx#some_adress/cat_mean_db",
["tasks"]);
everything is working well, but when I try to use db on localhost I got an exeption: connection 0 to localhost:3000 closed
the local db is exist and has user for shure.
From mongoose documentation on NPM :
Note: If the local connection fails then try using 127.0.0.1 instead of localhost. Sometimes issues may arise when the local hostname has been changed.
You should try using 127.0.0.1 instead of localhost.

Mongoose never returns its promise when I try to connect to the same db using a working URL

I have a locally hosted mongodb that I can connect to using mongodb.MongoClient.
Working code:
var mongoClient = require("mongodb").MongoClient;
...
var startApp = function(db) {
// Get our collections in an easy to use format
var database = {
chats: db.collection('chats'),
messages: db.collection('messages')
};
// Configure our routes
require('./app/routes')(app, database);
// START APP
// Start app on port
app.listen(port);
// Tell user the app is running
console.log("App running on port " + port);
// Expose app
exports = module.exports = app;
}
// DATABASE
var database = null;
mongoClient.connect(config.url, function(err, returnDB) {
if(err) {
console.log(err);
} else {
console.log("DB connected");
startApp(returnDB);
}
});
Legacy code that no longer works:
var mongoose = require('mongoose');
...
// Connect to DB
console.log('Connect to database (' + db.url + ')');
mongoose.connect(db.url);
I have added a callback to this connect method but it never gets called (error or no error, this connect function never gets to my callback).
This entire legacy app relies on the API using mongoose to talk to the database so I do not want to redo it all using mongodb. How can I fix this?
*config.url and db.url are loaded from the same file and it is a valid and running mongodb.
It was really easy to fix. Thanks #Bhavik for asking me what version I was using.
I updated mongoose to 4.8.1 by specifying the newest version in packages.json and the issue is resolved.

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