db.js

var pg = require(‘pg’), connString = ‘***’;

function DB(cb) {                                                                                                          
  var that = this;                                                                                                         
  pg.connect(connString, function(err, client, done) {                                                                     
    if (err) return cb(err);                                                                                               
    that.client = client;                                                                                                  
    cb(null, that);                                                                                                        
  });                                                                                                                      
}

DB.protoytpe.getUser = function(email, cb) { };
DB.prototype.getCompany = function(id, cb) { };