请教个关于 NODE JS MYSQL 的初级问题

var mysql      = require('mysql');
var connection = mysql.createConnection({
  host     : 'localhost',
  user     : 'dbuser',
  port     : '3306',
  password : 'pwd',
  database : 'dbname'
});

connection.connect();

connection.query('select * from tablename', function(err, rows, fields) {
  if (err) {
    console.log(err.message);
}

  console.log('The solution is: ', rows);
});

connection.end();

{ [Error: connect ETIMEDOUT]
  errorno: 'ETIMEDOUT',
  code: 'ETIMEDOUT',
  syscall: 'connect',
  fatal: true }