how to catch Sequelize connection error - node.js

Question

How to catch a sequelize connection error in case there is one?
I tried to do
var connection = new Sequelize("db://uri");
connection.on("error", function() { /* perhaps reconnect here */ });
but apparently this is not supported.
I wanted to do this because I think sequelize might be throwing an occasional unhandled ETIMEOUT and crashing my node process.
Currently I am using sequelize to connect a mysql instance. I only need it for like 2-3 hours and during that time I will be doing a many read queries. The mysql server will not be connected to anything else during that time.

Answer 1

Using sync() for this is considerably dangerous when using external migrations or when database integrity is paramount (when isn't it!)
The more up-to-date way of doing this is to use authenticate()
sequelize
.authenticate()
.then(() => {
console.log('Connection has been established successfully.');
})
.catch(err => {
console.error('Unable to connect to the database:', err);
});

Answer 2

Using sequelize sync method provides an easy way to catch the error.
The then block handles a Successful connection and the catch handles the rejection.To get a detailed reason for a failure access the error object.
example: error.message e.t.c
Hope this helps.
sequelize.sync().
then(function() {
console.log('DB connection sucessful.');
}).catch(err=> console.log('error has occured'));

Answer 3

Use sequelize sync for that
var Sequelize = require('sequelize');
sequelize = new Sequelize(config.database, config.username, config.password, {
'host' : config.host,
'dialect' : config.dialect,
'port' : config.port,
'logging' : false
})
sequelize.sync().then(function(){
console.log('DB connection sucessful.');
}, function(err){
// catch error here
console.log(err);
});