How to reconnect when the database is disconnected?

Question

MySQL

I'm using the 'mysql' module for node.js . The server connects to mysql remotely. When the database is turned off, the server constantly crashes and you have to turn it on manually via "systemctl" (for some reason, systemctl makes about 10 turns on after 1 second and stops). I found a code on github that does reconnect until the connection is restored.

function handleDisconnect(myconnection) {
    myconnection.on('error', function (err) {
        console.log('\nRe-connecting lost connection: ' + new Date());
        con.destroy();
        con = mysql.createConnection(options);
        handleDisconnect(con);
        con.connect();
    });
}
handleDisconnect(con);

The function works as it should.
However, when queries are started in the database ( query("SELECT ..." ), then when the database is disabled, the if(err) throw err; error handler is triggered and the server crashes.
What are the standard means to avoid server crashes?

Answer 1

design:

try { 
... 
} catch(err) {
...
}

thus the server will not fall more details here