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I can't access to mySQL with node js anymore

I have updated my node version, and now I can't access to my DB with my app. I tried many things:
-Change rout to 127.0.0.1.
-add my port number 3306
-add socketPath: '/Applications/MAMP/tmp/mysql/mysql.sock'
-kill node running
And probably others, but I always have an error. Actually, I have this one while running this code.
Error:
disconnected
error: connect ECONNREFUSED ::1:3306
My code who was working before:
const mysql = require('mysql');
const db = mysql.createConnection({
host: "localhost",
user: "root",
password: "",
database: "discord"
});
if (db.state === 'disconnected') {
db.connect(function (err) {
if (err) { return console.error('error: ' + err.message); }
console.log('Connected to the MySQL server.');
});
}
console.log(db.state);
module.exports = db

My issue was the version of discord.js because I have updated it as well. I've changed it in my package.json for the one I used before and everything is working well. It will be hard to update all my app to the new version. If you have any recommendation to update it easily without running into multiple issues, I'm here !

Error: read ECONNRESET when connected to a mysql server with Node.js

I'm trying to establish a simple connection to my database with the mysql npm package. At first glance, everything works fine and I can get the information I need, however, if I leave the server running for some time I get the following error:
Error: read ECONNRESET
at TCP.onStreamRead
const express = require('express');
const app = express();`
const mysql = require('mysql');
const db = mysql.createConnection({
host: 'XXXX.mysql.database.azure.com',
user: 'XXXXX',
password: 'XXXXX',
database: 'XXXXX'
})
db.connect((err)=>{
if(err){
console.log(err.message);
} else {
console.log('Connected to the database');
}
})
As far as I understand the problem stems from the database connection being in idle mode. Do I need to configure the Azure server or is there something else I need to do?

Couple of things to try:
You can try creating connection pool instead of **createConnection**
mysql.createPool({});
Modify your package.json like below:
"dependencies": {
"mysql": "git://github.com/mysqljs/mysql#e3e123e9af7c0829a6c1417d911572a75b4a5f95"
},
It is described in detail here:
Bad handshake or ECONNRESET Azure Mysql Nodejs
https://social.msdn.microsoft.com/Forums/en-US/c8fedbcc-909d-41ce-8c72-0374f76fdf82/cannot-connect-from-nodejs?forum=AzureDatabaseforMySQL
Hope it helps.

SequelizeConnectionError in Node.js application

I have strange problem and don't know in what place is the problem. I will be grateful for any help.
I have Node.js application which works fine in local windows 10 computer. I run this application successfully in Docker which is in CentOS server. This application works with remote MySQL and PostgreSQL databases. It worked correctly several days but yestoday I notice that I have error. Application can't connect to remote MySQL database anymore. In the same time I can connect to that remote MySQL database without any problem if I run application in my local computer or connect by DBeaver/dbForge tool.
MySQL.js:
const Sequelize = require('sequelize');
const sequelize = new Sequelize('database_name', 'username', 'password', {
host: 'host',
dialect: 'mysql'
});
sequelize.authenticate().then(() => {
console.log('Connection to database has been established successfully.');
}).catch(err => {
console.error('Unable to connect to database:', err);
});
module.exports = sequelize;
routes.js:
const express = require('express');
const router = express.Router();
const sequelize = require('../configurations/MySQL');
const Sequelize = require('sequelize');
const passport = require('passport');
require('../configurations/password')(passport);
router.post('/search_by_name', passport.authenticate('jwt', {session: false}, null), function(req, res) {
const token = getToken(req.headers);
if (token) {
sequelize.query("LONG SQL QUERY", {
replacements: {
name: req.body.name,
},
type: Sequelize.QueryTypes.SELECT
}).then((locations) => {
res.status(200).send(locations)
}).catch((error) => {
res.status(400).send(error);
});
} else {
return res.status(401).send({
status: false,
description: "Unauthorized"
});
}
});
As you can see I use sequelize library to connect application to remote MySQL database. The same library I use to connect to remote PostgreSQL database. As I said before error happens only when I try to connect to remote MySQL database in Docker. There is no error with PostgreSQL connection in Docker. Is it possible that problem inside Docker/network?
Dependencies:
"sequelize": "^4.42.0"
"mysql2": "^1.6.4"
I also thought that the reason of the problem can be because of much pools/connections and sequelize library don't close them automatically. For thats why I restarted docker сontainer several times hoping to confirm the theory. Unfortunately the error do not disappear.
How do you think, what happens?
Error:
Unable to connect to the database: { SequelizeConnectionError: connect ETIMEDOUT
at Utils.Promise.tap.then.catch.err (/node_modules/sequelize/lib/dialects/mysql/connection-manager.js:149:19)
at tryCatcher (/node_modules/bluebird/js/release/util.js:16:23)
at Promise._settlePromiseFromHandler (/node_modules/bluebird/js/release/promise.js:512:31)
at Promise._settlePromise (/node_modules/bluebird/js/release/promise.js:569:18)
at Promise._settlePromise0 (/node_modules/bluebird/js/release/promise.js:614:10)
at Promise._settlePromises (/node_modules/bluebird/js/release/promise.js:690:18)
at _drainQueueStep (/node_modules/bluebird/js/release/async.js:138:12)
at _drainQueue (/node_modules/bluebird/js/release/async.js:131:9)
at Async._drainQueues (/node_modules/bluebird/js/release/async.js:147:5)
at Immediate.Async.drainQueues [as _onImmediate] (/node_modules/bluebird/js/release/async.js:17:14)
at processImmediate (timers.js:632:19)
name: 'SequelizeConnectionError',
parent:
{ Error: connect ETIMEDOUT
at Connection._handleTimeoutError (/node_modules/mysql2/lib/connection.js:173:17)
at listOnTimeout (timers.js:324:15)
at processTimers (timers.js:268:5)
errorno: 'ETIMEDOUT',
code: 'ETIMEDOUT',
syscall: 'connect',
fatal: true },
original:
{ Error: connect ETIMEDOUT
at Connection._handleTimeoutError (/node_modules/mysql2/lib/connection.js:173:17)
at listOnTimeout (timers.js:324:15)
at processTimers (timers.js:268:5)
errorno: 'ETIMEDOUT',
code: 'ETIMEDOUT',
syscall: 'connect',
fatal: true }}

Try to add pool option when new Sequelize. Reference document
Sequelize will setup a connection pool on initialization so you should
ideally only ever create one instance per database if you're
connecting to the DB from a single process. If you're connecting to
the DB from multiple processes, you'll have to create one instance per
process, but each instance should have a maximum connection pool size
of "max connection pool size divided by number of instances". So, if
you wanted a max connection pool size of 90 and you had 3 worker
processes, each process's instance should have a max connection pool
size of 30.
const Sequelize = require('sequelize');
const sequelize = new Sequelize('database_name', 'username', 'password', {
host: 'host',
dialect: 'mysql',
pool: {
max: 15,
min: 5,
idle: 20000,
evict: 15000,
acquire: 30000
},
});
module.exports = sequelize;
Also, you can check more option at here
options.pool sequelize connection pool configuration
options.pool.max default: 5 Maximum number of connection in pool
options.pool.min default: 0 Minimum number of connection in pool
options.pool.idle default: 10000 The maximum time, in milliseconds,
that a connection can be idle before being released. Use with
combination of evict for proper working, for more details read
https://github.com/coopernurse/node-pool/issues/178#issuecomment-327110870
options.pool.acquire default: 10000 The maximum time, in milliseconds,
that pool will try to get connection before throwing error
options.pool.evict default: 10000 The time interval, in milliseconds,
for evicting stale connections. Set it to 0 to disable this feature.
options.pool.handleDisconnects default: true Controls if pool should
handle connection disconnect automatically without throwing errors
options.pool.validate A function that validates a connection. Called
with client. The default function checks that client is an object, and
that its state is not disconnected

In the simple terms i want to say that these type of error comes when your some configuration wrong entered. these are :
DB Name
Username
Password
so please cross verify your these things in your congif.json file

I would recommend to check the Database Hostname. Please try to resolve the hostname, if it is given IP address instead of domain. This would resolve the issue.

node.js - Can't connect to MYSQL database with Sequelize

I'm starting at Node.js and i'm trying to make a simple connection with Sequelize based on its documentation (http://docs.sequelizejs.com/manual/installation/getting-started.html#installation).
Here my db.js file :
const Sequelize = require('sequelize')
const db = new Sequelize('chat','root','root',{
host: 'localhost',
port: 3306,
dialect: 'mysql'
});
db
.authenticate()
.then(() => {
console.log('Connection has been established successfully.');
})
.catch(err => {
console.error('Unable to connect to the database:', err);
});
When executing this code, I have no success nor error message, just a message indicating 'String base operators deprecated' but nothing important i think.
I tried changing localhost to 127.0.0.1, remove port number and multiples thread but i'm stucked here...

Tested your code and all seemed to work fine, it connected successfully to the database instance I have running.
You might want to ensure mysql2 package is installed. Also check that the database chat has been created in MySQL workbench, and ensure the password is correct.

Node.js with mySQL -> Connection refused to 127.0.0.1 : 3306

First, I have this code here for the server, which works perfectly
var app = require('express')();
var mysql = require('mysql');
app.get('/', function (req, res) {
res.sendFile(__dirname + "/start.html");
});
app.listen(3000);
But, if I try to create a connection to a database, it says that the connection is refused to 127.0.0.1 : 3036
var db = mysql.createConnection({
host: 'localhost',
user: 'root',
password: '',
database: 'user_data'
});
db.connect();
I am using XAMMP :
Click here -> MySQL / Apache
So what is the problem? I don't understand. I also get this error when I try to access phpMyAdmin :
Link to the error

You need to specify a port as your database is listening on a non standard port
var db = mysql.createConnection({
host: 'localhost',
user: 'root',
password: '',
database: 'user_data',
port: 3036
});
db.connect();
For phpMyAdmin, you need to find config.inc.php in phpMyAdmin's top level directory and edit the line where it says
$cfg['Servers'][$i]['port']
to the port you are using. And you need to change
$cfg['Servers'][$i]['host']
to 127.0.0.1 instead of localhost, because:
If you use localhost as the hostname, MySQL ignores this port number and connects with the socket, so if you want to connect to a port different from the default port, use 127.0.0.1 or the real hostname in $cfg['Servers'][$i]['host'].
Documentation on phpMyAdmin