I'm running MongoDB Atlas on node express and I got this error when I tested with postman.
const express = require('express');
const cors = require('cors');
const mongoose = require('mongoose');
require('dotenv').config();
const app = express();
const port = process.env.PORT || 5000;
app.use(cors());
app.use(express.json());
const uri = process.env.ATLAS_URI;
mongoose.connect(uri, { useNewUrlParser: true, useCreateIndex: true }
);
const connection = mongoose.connection;
connection.once('open', () => {
console.log("MongoDB database connection established successfully");
})
const exercisesRouter = require('./routes/exercises');
const usersRouter = require('./routes/users');
app.use('/exercises', exercisesRouter);
app.use('/users', usersRouter);
app.listen(port, () => {
console.log(`Server is running on port: ${port}`);
});
This is my .env, I'm guessing the problem might be here too, Kindly help:
ATLAS_URI=mongodb+srv://userone:useronepassword1234@cluster0.swye5.mongodb.net/<dbname>?retryWrites=true&w=majority
First replace <dbname> with your actual DB name, if not created,
create one.
Then create collection as required on the Atlas UI itself.
In the Network Access, click on ADD IP ADDRESS and select "allow access from anywhere".
Rewrite your code this way:
mongoose
.connect(process.env.MONGO_PROD_URI, {
useNewUrlParser: true,
useUnifiedTopology: true,
useCreateIndex: true, })
.then(() => console.log("Database connected!"))
.catch(err => console.log(err));
If still not resolved, check this link.
I was facing the same issue. It is resolved. I think you might have not allowed network access to everyone in Atlas: MongoDB. Do it will resolve the issue.
In my case, I had to go to Atlas, and reset my whitelisted IP to the correct address.
Then I restarted my local server and tried posting again on postman... And it worked!
If you are seeing this using Typescript ensure you are importing the connect function from mongoose and use that to connect.
import { connect } from "mongoose";
connect(...).then()
Check your Network Access IP list in MongoDB Cloud.You will only be able to connect to your cluster from the list of IP Addresses
Ensure that your IP Address Setting is Active
Check if you didn't forgot to set password in connection string.
It's kind of late but probably because of this line useCreateIndex: true it's not working. It seems in mongoDB version 5. this is not supported anymore. Rewrite like the answer of manoj_mi5
mongoose
.connect(process.env.MONGODB_URL, {
useNewUrlParser: true,
useUnifiedTopology: true})
.then(() => console.log("Database connected!"))
.catch(err => console.log(err));
to check if there are more errors.
Change your MongoDB database-user password. It should be alphanumeric with no special characters. Nothing worked out for me, but, changing the password did.
Go to your Atlas account and open your project.
In the left menu, navigate to Network Access section:
Add your IP Address so only you would be able to connect to your cluster. You can also add 0.0.0.0/0 and it will allow access from everywhere.
I also faced the same error. In my case, the error was coming up because useFindAndModify was set to false in mongoose connection
Code with error
mongoose.connect(dbUrl, {
useNewUrlParser: true,
useUnifiedTopology: true,
useFindAndModify: false
}, () => {
console.log('connected to database myDb ;)')
})
Working Code
mongoose.connect(dbUrl, {
useNewUrlParser: true,
useUnifiedTopology: true
}, () => {
console.log('connected to database myDb ;)')
})
"error:MongooseError: Operation users.insertOne() buffering timed out after 10000ms"
mongoose.connect(process.env.MONGO_URL, {
useNewURLParser: true,
useUnifiedTopology: true,
useCreateIndex: true,
},6000000)
.then(console.log("connected to server"))
.catch((err) => console.log(err));
add time like 6000000 after options
In Mongoose version 6 and above don't require those
{ useNewUrlParser: true,
useUnifiedTopology: true,
useCreateIndex: true,
useFindAndModify: false
}
so just delete it.
And if you still see app crashed - waiting for file changes before starting...
just save it one more time and it will work
In Latest version of mongoose.
we don't require this object.
{ useNewUrlParser: true, useUnifiedTopology: true, useCreateIndex: true, useFindAndModify: false }
But if you are dealing with older versions of mongoose then definetly you need it. Also in your mongodb network address add this address 0.0.0.0/0 in place of your ip address.
in this line of code, ATLAS_URI=mongodb+srv://userone:useronepassword1234@cluster0.swye5.mongodb.net/?retryWrites=true&w=majority
make sure you write actual database name without < > symbols. You have to create your database first in Mongo Atlas.

To solve this, I created a function in index.js, where I asynchronically connecting to my Database and then starting the server, because mongoose doesn't wait for db connection it executes everything on spot, form that was the problem.
async function start() {
try {
//Database Connect
await mongoose.connect(
process.env.DB_CONNECTION,
{
useNewUrlParser: true,
useUnifiedTopology: true,
},
() => {
console.log("Database Connected");
}
);
app.listen(3000, () => {
console.log("Server is running on port 3000 ...");
});
} catch (error) {
console.error(error);
}
}