db.js

var db = (function(){

  var mysql = require('mysql');

  var host     = 'localhost';
  var database = 'me';
  var password = '';
  var user     = 'root';

  return {

    get_dbh: function () {

      var connection = mysql.createConnection({
        host     : host,
        database : database,
        password : password,
        user     : user
      });

      return connection;
    }

  };

})();
~
~
"db.js" 26L, 410C written

run.js

var db = require('./db.js');
console.log(db);
process.kill();

STDOUT

Andy-MacBook:twitter-stream andy$ node run.js start
{}