JavaScript for date string

date_string.js

// produce a data string in this format: 2015-12-17 01:31:39

function getDate() {
    var date = new Date();
    timestamp = date.getUTCFullYear() + '-' +
        ('00' + (date.getUTCMonth() + 1)).slice(-2) + '-' +
        ('00' + date.getUTCDate()).slice(-2) + ' ' +
        ('00' + date.getUTCHours()).slice(-2) + ':' +
        ('00' + date.getUTCMinutes()).slice(-2) + ':' +
        ('00' + date.getUTCSeconds()).slice(-2);
    return timestamp;
}