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Node.JS won't connect to MariaDB

I can't seem to get the example program to work from MariaDB's documentation.
Here's the code I am using which is a minimally modified version from the example in the docs.
const mariadb = require('mariadb');
const pool = mariadb.createPool({
host: 'localhost',
user: 'admin',
password: 'adminpassword',
database: 'userdb',
port: 3306,
connectionLimit: 5
});
async function f() {
console.log(pool);
let connection;
try {
console.log('Connection start');
connection = await pool.getConnection();
console.log('Connected');
const rows = await connection.query('select * from users');
console.log(rows);
const res = await connection.query('insert into users value (?, ?)', [1, 'testuser']);
console.log(res);
await connection.release();
}
catch(exception) {
console.log(exception);
}
if(connection) {
return connection.end();
}
}
f();
This is the output that I obtain if I run this code.
ode index.js
PoolPromise {
_events: [Object: null prototype] {},
_eventsCount: 0,
_maxListeners: undefined,
[Symbol(kCapture)]: false
}
Connection start
SqlError: (conn=-1, no: 45028, SQLState: HY000) retrieve connection from pool timeout after 10001ms
(pool connections: active=0 idle=0 limit=5)
at module.exports.createError (.../node_modules/mariadb/lib/misc/errors.js:57:10)
at Pool._requestTimeoutHandler (.../node_modules/mariadb/lib/pool.js:345:26)
at listOnTimeout (node:internal/timers:564:17)
at process.processTimers (node:internal/timers:507:7) {
text: 'retrieve connection from pool timeout after 10001ms\n' +
' (pool connections: active=0 idle=0 limit=5)',
sql: null,
fatal: false,
errno: 45028,
sqlState: 'HY000',
code: 'ER_GET_CONNECTION_TIMEOUT'
}
node:internal/process/promises:289
triggerUncaughtException(err, true /* fromPromise */);
^
Error: connect ECONNREFUSED ::1:3306
at TCPConnectWrap.afterConnect [as oncomplete] (node:net:1471:16)
From event:
at .../node_modules/mariadb/lib/connection.js:115:13
at new Promise (<anonymous>)
at Connection.connect (.../node_modules/mariadb/lib/connection.js:103:12)
at Pool._createConnection (.../node_modules/mariadb/lib/pool.js:402:16)
at Pool._doCreateConnection (.../node_modules/mariadb/lib/pool.js:40:10)
at listOnTimeout (node:internal/timers:564:17)
at process.processTimers (node:internal/timers:507:7)
Emitted 'error' event on PoolPromise instance at:
at Pool.emit (node:events:513:28)
at .../node_modules/mariadb/lib/pool.js:258:22
at process.processTicksAndRejections (node:internal/process/task_queues:95:5) {
errno: -111,
code: 'ECONNREFUSED',
syscall: 'connect',
address: '::1',
port: 3306,
fatal: true,
sqlState: 'HY000'
}
Node.js v19.3.0
My questions are any one of the following:
Why does this happen?
Where can I find the logs to obtain more information?
Do I have to enable the logs, if so, how?
How can I debug this issue?
I can connect perfectly fine using the CLI and Beekeeper Studio.

There doesn't seem to be a mariadb connection option to make non IP hostname lookup favor IPv4. The general resolve order fix shown in https://github.com/nodejs/node/issues/40537#issuecomment-1237194449:
import dns from 'node:dns';
dns.setDefaultResultOrder('ipv4first');
may fix this, but would affect things other than the database connection.
Other than that, it seems your choices are to specify 127.0.0.1 instead of localhost, or to configure your server to also listen on ::1.

It seems to be trying to connect over ipv6 (::1). I suspect that your MariaDb instance only bound to an ipv4 address, and hence host: '127.0.0.1' might work.
You can try that or use ss -atnl | grep 3306 to see what addresses MariaDB is bound to.

You computer is assigned IPs from IPV4 and IPV6 and by default dns resolve to localhost for IPV6 which is incorrectly assigned.
To fix this error either configure your DHCP to assign proper IPV6 or change host:127.0.0.1 (simple and quick fix)

Not able to connect MongoDB Atlas with Node.js trough Mongoose

I'm trying to connect a Node.js application with MongoDB Atlas trough Mongoose and I'm getting the following error:
MongooseServerSelectionError: Could not connect to any servers in your MongoDB Atlas cluster. One common reason is that you're trying to access the
database from an IP that isn't whitelisted. Make sure your current IP address is on your Atlas cluster's IP whitelist: https://docs.atlas.mongodb.com/security-whitelist/
at NativeConnection.Connection.openUri (C:\Users\marin\Downloads\Project part2\Project part2\docker_app\node_modules\mongoose\lib\connection.js:797:32)
at C:\Users\marin\Downloads\Project part2\Project part2\docker_app\node_modules\mongoose\lib\index.js:332:10
at C:\Users\marin\Downloads\Project part2\Project part2\docker_app\node_modules\mongoose\lib\helpers\promiseOrCallback.js:32:5
at new Promise (<anonymous>)
at promiseOrCallback (C:\Users\marin\Downloads\Project part2\Project part2\docker_app\node_modules\mongoose\lib\helpers\promiseOrCallback.js:31:10)
at Mongoose._promiseOrCallback (C:\Users\marin\Downloads\Project part2\Project part2\docker_app\node_modules\mongoose\lib\index.js:1153:10)
at Mongoose.connect (C:\Users\marin\Downloads\Project part2\Project part2\docker_app\node_modules\mongoose\lib\index.js:331:20)
at connectDb (C:\Users\marin\Downloads\Project part2\Project part2\docker_app\src\connection.js:9:6)
at Server.<anonymous> (C:\Users\marin\Downloads\Project part2\Project part2\docker_app\server.js:27:3)
at Object.onceWrapper (events.js:519:28) {
reason: TopologyDescription {
type: 'Unknown',
servers: Map(1) {
'cluster0.huaic.mongodb.net:27017' => [ServerDescription]
},
stale: false,
compatible: true,
heartbeatFrequencyMS: 10000,
localThresholdMS: 15,
logicalSessionTimeoutMinutes: undefined
}
}
My code is:
const mongoose = require("mongoose");
const User = require("./User.model");
const connection = '"mongodb://cluster0.huaic.mongodb.net/myFirstDatabase"';
const connectDb = () => {
return mongoose
.connect(connection)
.then((res) => {
return res;
})
.catch((error) => {
console.log(error);
});
};
module.exports = connectDb;
I've allowed access from every IP on mongodb atlas and when I try to connect directly to atlas everything works fine.

For first, you have double quotes in the connection variable. Secondly: it seems to me that mongoUri should include the username and password in the query string, right?

Make sure your connection string is like below. It should include your username and password:
"mongodb+srv://username:password#cluster0.huaic.mongodb.net/yourdatabasename?retryWrites=true&w=majority"
Set up a user that has that password and that username by going to Database Access in your atlas account.

MongooseServerSelectionError: connect ECONNREFUSED ::1:27017

I have a problem when I try to connect my app with my database with Mongoose. Already tried following solutions that I found on google:
restarting MongoDB service on windows
manually open db with cmd located on bin file of mongodb
But I can't solve it. Can anyone help me ?
//my connection
const mongoose = require('mongoose');
mongoose.connect('mongodb://localhost/notes-db-app',{
useNewUrlParser: true,
useUnifiedTopology: true
})
.then(db => console.log('DB is connected'))
.catch(err => console.log(err));
And throw's me , this error
MongooseServerSelectionError: connect ECONNREFUSED ::1:27017
at NativeConnection.Connection.openUri (C:\Users\ivan\Desktop\NodeJS\notes-app\node_modules\mongoose\lib\connection.js:797:32)
at C:\Users\ivan\Desktop\NodeJS\notes-app\node_modules\mongoose\lib\index.js:330:10 at C:\Users\ivan\Desktop\NodeJS\notes-app\node_modules\mongoose\lib\helpers\promiseOrCallback.js:32:5
at new Promise ()
at promiseOrCallback (C:\Users\ivan\Desktop\NodeJS\notes-app\node_modules\mongoose\lib\helpers\promiseOrCallback.js:31:10)
at Mongoose._promiseOrCallback (C:\Users\ivan\Desktop\NodeJS\notes-app\node_modules\mongoose\lib\index.js:1151:10)
at Mongoose.connect (C:\Users\ivan\Desktop\NodeJS\notes-app\node_modules\mongoose\lib\index.js:329:20)
at Object. (C:\Users\ivan\Desktop\NodeJS\notes-app\src\db.js:3:10)
at Module._compile (node:internal/modules/cjs/loader:1095:14)
at Object.Module._extensions..js (node:internal/modules/cjs/loader:1147:10) {
reason: TopologyDescription {
type: 'Unknown',
servers: Map(1) { 'localhost:27017' => [ServerDescription] },
stale: false,
compatible: true,
heartbeatFrequencyMS: 10000,
localThresholdMS: 15,
logicalSessionTimeoutMinutes: undefined
}
}
I try to put the port on my connection code like this
//my connection
const mongoose = require('mongoose');
mongoose.connect('mongodb://localhost:27017/notes-db-app',{
useNewUrlParser: true,
useUnifiedTopology: true
})
.then(db => console.log('DB is connected'))
.catch(err => console.log(err));
and it throw's me another error
MongooseServerSelectionError: Invalid message size: 1347703880, max allowed: 67108864
at NativeConnection.Connection.openUri (C:\Users\ivan\Desktop\NodeJS\notes-app\node_modules\mongoose\lib\connection.js:797:32)
at C:\Users\ivan\Desktop\NodeJS\notes-app\node_modules\mongoose\lib\index.js:330:10 at C:\Users\ivan\Desktop\NodeJS\notes-app\node_modules\mongoose\lib\helpers\promiseOrCallback.js:32:5
at new Promise ()
at promiseOrCallback (C:\Users\ivan\Desktop\NodeJS\notes-app\node_modules\mongoose\lib\helpers\promiseOrCallback.js:31:10)
at Mongoose._promiseOrCallback (C:\Users\ivan\Desktop\NodeJS\notes-app\node_modules\mongoose\lib\index.js:1151:10)
at Mongoose.connect (C:\Users\ivan\Desktop\NodeJS\notes-app\node_modules\mongoose\lib\index.js:329:20)
at Object. (C:\Users\ivan\Desktop\NodeJS\notes-app\src\db.js:3:10)
at Module._compile (node:internal/modules/cjs/loader:1095:14)
at Object.Module._extensions..js (node:internal/modules/cjs/loader:1147:10) {
reason: TopologyDescription {
type: 'Unknown',
servers: Map(1) { 'localhost:3000' => [ServerDescription] },
stale: false,
compatible: true,
heartbeatFrequencyMS: 10000,
localThresholdMS: 15,
logicalSessionTimeoutMinutes: undefined
}
}

If the Error states:
connect() Error :MongooseServerSelectionError: connect ECONNREFUSED ::1:27017
Then the connection to localhost is refused on the IPv6 address ::1 .
Mongoose per default uses IPv6 ..
For a quick check you can set the IPv4 address explicit:
mongoose.connect('mongodb://127.0.0.1/test')

Simply pass third parameter family:4 ie.
mongoose.connect('mongodb://localhost/notes-db-app',{
useNewUrlParser: true,
useUnifiedTopology: true,
family: 4,
})

I finally solved it.
Enabling the IPV6 that MongoDB has disabled by default. Using the following command line on CMD:
mongod --ipv6
And then try again the connection and it works!
const mongoose = require('mongoose');
mongoose.connect('mongodb://localhost/notes-db-app',{
useNewUrlParser: true,
useUnifiedTopology: true
})
.then(db => console.log('DB is connected'))
.catch(err => console.log(err));
Posted on behalf of the question asker

const uri = 'mongodb://localhost:27017/test';
const options = {
useNewUrlParser: true,
useUnifiedTopology: true,
serverSelectionTimeoutMS: 5000,
autoIndex: false, // Don't build indexes
maxPoolSize: 10, // Maintain up to 10 socket connections
serverSelectionTimeoutMS: 5000, // Keep trying to send operations for 5 seconds
socketTimeoutMS: 45000, // Close sockets after 45 seconds of inactivity
family: 4 // Use IPv4, skip trying IPv6
}
const connectWithDB = () => {
mongoose.connect(uri, options, (err, db) => {
if (err) console.error(err);
else console.log("database connection")
})
}
connectWithDB()

Probably the hostname/IP of the server to which you want to connect is not correctly set.
I'm used to see that error as:
MongooseServerSelectionError: connect ECONNREFUSED <hostname/hostIP>:<port>
and in the console log you've posted, the <hostname/hostIP> part is malformed/missing.
Example - for a mongodb server running locally on port 27017 this is the error when server is down:
MongooseServerSelectionError: connect ECONNREFUSED 127.0.0.1:27017
If you're using mongodb URI to connect to the db make sure that it looks like this
"mongodb://<hostname/hostIP>:<port>"

Problem is, the localhost alias resolves to IPv6 address ::1 instead of 127.0.0.1
However, net.ipv6 defaults to false.
The best option would be to start the MongoDB with this configuration:
net:
ipv6: true
bindIpAll: true
or
net:
ipv6: true
bindIp: localhost
Then all variants should work:
C:\>mongosh "mongodb://localhost:27017" --quiet --eval "db.getMongo()"
mongodb://localhost:27017/?directConnection=true&serverSelectionTimeoutMS=2000&appName=mongosh+1.6.0
C:\>mongosh "mongodb://127.0.0.1:27017" --quiet --eval "db.getMongo()"
mongodb://127.0.0.1:27017/?directConnection=true&serverSelectionTimeoutMS=2000&appName=mongosh+1.6.0
C:\>mongosh "mongodb://[::1]:27017" --quiet --eval "db.getMongo()"
mongodb://[::1]:27017/?directConnection=true&appName=mongosh+1.6.0
If you don't run MongoDB as a service then it would be
mongod --bind_ip_all --ipv6 <other options>
NB, I don't like configuration
net:
bindIp: <ip_address>
in my opinion this makes only sense on a computer with multiple network interfaces. Use bindIp: localhost if you need to prevent any connections from remote computer (e.g. while maintenance or when used as backend database for a web-service), otherwise use bindIpAll: true

Open your terminal and type this command: mongod
Then use your app.js to establish a connection by writing this code :
const mongoose=require("mongoose");
mongoose.connect('mongodb://localhost/notes-db-app',{
useNewUrlParser: true,
useUnifiedTopology: true,
family: 4,
})
It's done now. Simply open your mongo shell or your mongodb compass and look for whatever you have added.

I also faced the same problem those commands worked for me(Ubuntu machine)
sudo chown -R mongodb:mongodb /var/lib/mongodb
sudo chown mongodb:mongodb /tmp/mongodb-27017.sock
Then
sudo service mongod restart

Got the Error "MongooseServerSelectionError: Server selection timed out after 30000 ms"

I got the Error MongooseServerSelectionError: Server selection timed out after 30000 ms.
I am using MongoDB Atlas.
I've tried changing useUnifiedTopologyto false and my application doesn't crash, but I get the Error DeprecationWarning: current Server Discovery and Monitoring engine is deprecated, and will be removed in a future version. To use the new Server Discover and Monitoring engine, pass option { useUnifiedTopology: true } to the MongoClient constructor.
The whole error message:
MongooseServerSelectionError: Server selection timed out after 30000 ms
{
reason: TopologyDescription {
type: 'ReplicaSetWithPrimary',
setName: 'atlas-lhb3t7-shard-0',
maxSetVersion: 1,
maxElectionId: 7fffffff0000000000000005,
servers: Map {
'wolfgangtest-shard-00-02.q8jpm.mongodb.net:27017' => [ServerDescription],
'wolfgangtest-shard-00-00.q8jpm.mongodb.net:27017' => [ServerDescription],
'wolfgangtest-shard-00-01.q8jpm.mongodb.net:27017' => [ServerDescription]
},
stale: false,
compatible: true,
compatibilityError: null,
logicalSessionTimeoutMinutes: null,
heartbeatFrequencyMS: 10000,
localThresholdMS: 15,
commonWireVersion: 8
}
}
My Mongoose code:
const dbOptions = {
useNewUrlParser: true,
autoIndex: false,
poolSize: 5,
connectTimeoutMS: 10000,
family: 4,
useUnifiedTopology: true
};
mongoose.connect('mongodb+srv://Wolfgang:christian13561z#wolfgangtest.q8jpm.mongodb.net/Wolfgang?retryWrites=true&w=majority', dbOptions);
mongoose.set('useFindAndModify', false);
mongoose.Promise = global.Promise;
How do i fix / bypass this?

I think that there is a problem with your the connection URL from my experience with this kind of eror.Try
Try to use the same connecton URL in MongoDB compass if you use windows or robomongo.
You can also try to check :
MongoDB connection error: MongoTimeoutError: Server selection timed out after 30000 ms
MongoTimeoutError: Server selection timed out after 30000 ms while connecting to mongoDB
Server selection timed out after 10000 ms - Cannot connect Compass to mongoDB on localhost

i could'nt connect to mongodb anymore?

in the first try i could connect to my mongodb account at it worked correctly but after 24h hours i couldnt connect anymore at it show me this problem :
>
npm run start
> devconnector#1.0.0 start C:\Users\DELL\Desktop\devconnector
> node server.js
Server running on port 5000
MongoTimeoutError: Server selection timed out after 30000 ms
at Timeout._onTimeout (C:\Users\DELL\Desktop\devconnector\node_modules\mongodb\lib\core\sdam\topology.js:897:9)
at listOnTimeout (internal/timers.js:531:17)
at processTimers (internal/timers.js:475:7) {
name: 'MongoTimeoutError',
reason: MongoNetworkError: connection 79 to cluster0-shard-00-00-15tsv.mongodb.net:27017
closed
at TLSSocket.<anonymous> (C:\Users\DELL\Desktop\devconnector\node_modules\mongodb\lib\core\connection\connection.js:356:9)
at Object.onceWrapper (events.js:300:26)
at TLSSocket.emit (events.js:210:5)
at net.js:659:12
at TCP.done (_tls_wrap.js:481:7) {
name: 'MongoNetworkError',
errorLabels: [ 'TransientTransactionError' ],
[Symbol(mongoErrorContextSymbol)]: {}
},
[Symbol(mongoErrorContextSymbol)]: {}
}
this is my keys.js file : module.exports = {
mongoURI : "mongodb+srv://jassem:<*******>#cluster0-15tsv.mongodb.net/test",
} ;
and this my code to connect to my Mongodb account :
//Connect To mongoDB
mongoose
const express = require ('express') ; const mongoose = require ('mongoose') ;
.connect(db, {useUnifiedTopology: true, useNewUrlParser: true, useCreateIndex: true }) .then(()=> console.log('MongoDB connected')) .catch(err => console.log(err)) ;