docs: function createDb(config, dbUser, dbUserPass, dbName, cb) {
    log.logger.trace({user: dbUser, pwd: dbUserPass, name: dbName}, 'creating new datatbase');
    var url = config.mongoUrl;
    var admin = config.mongo.admin_auth.user;
    var admin_pass = config.mongo.admin_auth.pass;
  
    MongoClient.connect(url, function(err, db){
      if (err) return handleError(null, err, 'cannot open mongodb connection', cb);
  
      var targetDb = db.db(dbName);
      targetDb.authenticate(admin, admin_pass, {'authSource': 'admin'}, function(err) {
        if (err) return handleError(db, err, 'can not authenticate admin user', cb);
  
        // update for mongodb3.2 - need to remove user first
        targetDb.removeUser(dbUser, function(err) {
          if(err){
            log.logger.error(err, 'failed to remove user');
          }
          // add user to database
          targetDb.addUser(dbUser, dbUserPass, function(err, user) {
            if (err) return handleError(db, err, 'can not add user', cb);
            log.logger.trace({user: user, database: dbName}, 'mongo added new user');
            db.close();
            return cb();
          });
        });
      });
    });
  }