gistfile1.js

var pg = require('pg');
var async = require('async');
var _ = require('underscore');
var when = require('when');



var conString = "tcp://erp:erp@localhost/poc";

var authenFn = function(user, password) {
    var deferred = when.defer();

    pg.connect(conString, function(err, client, done) {
        if(err) {
            deferred.reject('connection error');
            return;
        }
        fetchUserFromDB(client, user).then(function(result) {
            if (password === result.password) {
                console.log('match')
                deferred.resolve(true);
            } else {
                console.log('mismatch')
                deferred.reject('password mismatch');
            }
        }, function(reason) {
            // user not found in db
            deferred.reject(reason);
        }).ensure(function() {
            done();
        });

    });

    return deferred.promise;
};

function fetchUserFromDB(client, user) {
    var deferred = when.defer();

    client.query('select username, password from users where username = $1', [user], function(err, result) {
        if (result.rows.length > 0) {
            console.log(result.rows[0])
            deferred.resolve({
                username: user,
                password: result.rows[0].password
            });
        } else {
            deferred.reject('no user found');
        }
    });

    return deferred.promise;
}


authenFn('pok', 'bunny').then(function() {
    console.log('login success');
}, function(reason) {
    console.log('fail with' + reason)
}).ensure(function() {
    pg.end();
})