Node.js MySQL – Error: connect ECONNREFUSED

You need to add the value of socket path to the config object:

socketPath: '/var/run/mysqld/mysqld.sock'

In MAMP, you go to http://localhost:8888/MAMP, and you find:

/Applications/MAMP/tmp/mysql/mysql.sock

At the end you have:

var connection = mysql.createConnection({
  host     : config.host,
  user     : config.user,
  password : config.pass,
  database : config.db,
  socketPath: '/Applications/MAMP/tmp/mysql/mysql.sock'
});