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Unable to return result from promise

I am trying to read some data from 2 different tables and parse a CSV file before rendering an ejs file.
I can get the data from both tables and from the CSV file but I seem to be unable to return the result.
Pretty sure this is a problem with the way I handle async execution but I fail to see what I am doing wrong.
I've spent the last 2 days reading about this (including the threads around here) and browsing but somehow the answer still escapes me.
First file - usercms.js
app.get('/userscms', function(req, res)
{
existingUsers.getExistingUsers()
.then(function(appUsers)
{
//global users array
//I can display these in my ejs file
globalAppUsers = appUsers;
})
.then(existingUsersAttributesQlik.getExistingUsersAttributesQlik())
.then(function(usersQlikAttributes)
{
//global user attributes array
//undefined data
globalUsersQlikAttributes = usersQlikAttributes;
})
.then(existingSuppliers.parseSuppliersCSV())
.then(function(supplierData)
{
//the result I am expecting
//this prints undefined
console.log(supplierData);
}).then(function()
{
res.render('userscms.ejs',
{
users: globalAppUsers,
attributes: globalUsersQlikAttributes
});
});
});
Second function - getxistingUsers.js (identical to the getExistingUsersAttributesQlik, except for the query)
var userData = [];
var appUsers = [];
(function (exports)
{
exports.getExistingUsers = function ()
{
return promisemysql.createConnection(dbconfig.development).then(function(conn)
{
var result = conn.query("SELECT id, username, firstName, lastName, email, phone, lastLogin, isAdmin, isValid, isPhoneValid, accountCreationDateTime FROM Users");
conn.end();
return result;
}).then(function(rows)
{
return rows;
}).then(function(rows)
{
if (rows.length)
{
userData = [];
appUsers = [];
rows.forEach(function (elem)
{
userData.push(_.toArray(elem));
});
for (i = 0; i < userData.length; i++)
{
var appUser = new appUserModel.AppUser(
userData[i][0],
userData[i][1],
userData[i][2],
userData[i][3],
userData[i][4],
userData[i][5],
userData[i][6],
userData[i][7],
userData[i][8],
userData[i][9],
userData[i][10]);
appUsers.push(_.toArray(appUser));
}
return appUsers;
}
else
{
console.log("NOPE");
return null;
}
}).then(function(appUsers)
{
console.log(appUsers);
return appUsers;
});
};
})(typeof exports === 'undefined' ? this['getExistingUsers'] = {} : exports);
Third file - parseSuppliersCSV.js
var supplierData = [];
var suppliersData = [];
var csvCount = 0;
(function (exports)
{
exports.parseSuppliersCSV = function ()
{
return new Promise(function(resolve, reject)
{
var fileStream = fs.createReadStream("myCSV.csv");
var parser = fastCsv();
csvCount = 0;
supplierData = [];
suppliersData = [];
fileStream
.on("readable", function ()
{
var data;
while ((data = fileStream.read()) !== null)
{
parser.write(data);
}
})
.on("end", function ()
{
parser.end();
});
parser
.on("readable", function ()
{
var data;
while ((data = parser.read()) !== null)
{
if(csvCount >= 1)
{
csvCount++;
var arrayOfStrings = data[0].split(';');
var supplier = new supplierModel.Supplier(arrayOfStrings[0],arrayOfStrings[1]);
suppliersData.push(_.toArray(supplier));
}
else
{
csvCount++;
}
}
})
.on("end", function ()
{
console.log("done");
//all OK here
console.log(suppliersData);
//this doesn't seem to return anything
return suppliersData;
});
});
};
})(typeof exports === 'undefined' ? this['parseSuppliersCSV'] = {} : exports);
Any ideas what I am doing wrong? Am I approaching this the wrong way?

I'll take a guess here and assume the promise you created should resolve to something...instead of returning a value.
.on("end", function ()
{
console.log("done");
//all OK here
console.log(suppliersData);
//this doesn't seem to return anything
return resolve(suppliersData);
});

JavaScript: Prevent Array.push()

I have a sealed object with an array member on which I want to prevent direct pushes.
var myModule = (function () {
"use strict";
var a = (function () {
var _b = {},
_c = _c = "",
_d = [];
Object.defineProperty(_b, "c", {
get: function () { return _c; }
});
Object.defineProperty(_b, "d", {
get { return _d; }
});
_b.addD = function (newD) {
_d.push(newD);
};
Object.seal(_b);
return _b;
}());
var _something = { B: _b };
return {
Something: _something,
AddD: _b.addD
};
}());
myModule.Something.c = "blah"; // doesn't update = WIN!!
myModule.AddD({}); // pushed = WIN!
myModule.Something.d.push({}); // pushed = sadness
How can I prevent the push?
UPDATE:
Thanks for all the thoughts. I eventually need the JSON to send to the server. It looks like I might need to use an object for the array then figure out a way to generate and return the JSON needed, or change _something to use .slice(). Will play and report.

you could override the push method:
var _d = [];
_d.__proto__.push = function() { return this.length; }
and when you need to use it in your module, call Array.prototype.push:
_b.addD = function (newD) {
Array.prototype.push.call(_d, newD);
};

I haven't done any performance tests on this, but this certainly helps to protect your array.
(function(undefined) {
var protectedArrays = [];
protectArray = function protectArray(arr) {
protectedArrays.push(arr);
return getPrivateUpdater(arr);
}
var isProtected = function(arr) {
return protectedArrays.indexOf(arr)>-1;
}
var getPrivateUpdater = function(arr) {
var ret = {};
Object.keys(funcBackups).forEach(function(funcName) {
ret[funcName] = funcBackups[funcName].bind(arr);
});
return ret;
}
var returnsNewArray = ['Array.prototype.splice'];
var returnsOriginalArray = ['Array.prototype.fill','Array.prototype.reverse','Array.prototype.copyWithin','Array.prototype.sort'];
var returnsLength = ['Array.prototype.push','Array.prototype.unshift'];
var returnsValue = ['Array.prototype.shift','Array.prototype.pop'];
var funcBackups = {};
overwriteFuncs(returnsNewArray, function() { return []; });
overwriteFuncs(returnsOriginalArray, function() { return this; });
overwriteFuncs(returnsLength, function() { return this.length; });
overwriteFuncs(returnsValue, function() { return undefined; });
function overwriteFuncs(funcs, ret) {
for(var i=0,c=funcs.length;i<c;i++)
{
var func = funcs[i];
var funcParts = func.split('.');
var obj = window;
for(var j=0,l=funcParts.length;j<l;j++)
{
(function() {
var part = funcParts[j];
if(j!=l-1) obj = obj[part];
else if(typeof obj[part] === "function")
{
var funcBk = obj[part];
funcBackups[funcBk.name] = funcBk;
obj[part] = renameFunction(funcBk.name, function() {
if(isProtected(this)) return ret.apply(this, arguments);
else return funcBk.apply(this,arguments);
});
}
})();
}
}
}
function renameFunction(name, fn) {
return (new Function("return function (call) { return function " + name +
" () { return call(this, arguments) }; };")())(Function.apply.bind(fn));
};
})();
You would use it like so:
var myArr = [];
var myArrInterface = protectArray(myArr);
myArr.push(5); //Doesn't work, but returns length as expected
myArrInterface.push(5); //Works as normal
This way, you can internally keep a copy of the interface that isn't made global to allow your helper funcs to modify the array as normal, but any attempt to use .push .splice etc will fail, either directly, or using the .bind(myArr,arg) method.
It's still not completely watertight, but a pretty good protector. You could potentially use the Object.defineProperty method to generate protected properties for the first 900 indexes, but I'm not sure of the implications of this. There is also the method Object.preventExtensions() but I'm unaware of a way to undo this effect when you need to change it yourself

Thank you, dandavis!
I used the slice method:
var myModule = (function () {
"use strict";
var a = (function () {
var _b = {},
_c = _c = "",
_d = [];
Object.defineProperty(_b, "c", {
get: function () { return _c; }
});
Object.defineProperty(_b, "d", {
get { return _d.slice(); } // UPDATED
});
_b.updateC = function (newValue) {
_c = newValue;
};
_b.addD = function (newD) {
_d.push(newD);
};
Object.seal(_b);
return _b;
}());
var _something = { B: _b };
return {
Something: _something,
AddD: _b.addD
};
}());
myModule.Something.c = "blah"; // doesn't update = WIN!!
myModule.AddD({}); // pushed = WIN!
myModule.Something.d.push({}); // no more update = happiness
This allows me to protect from direct push calls enforcing some logic.

How to create a class which has a property and a function with same name

I want to be able to call simultaneously something like this in javascript:
classInstance.room.get('criteria');
classInstance.room('criteria').remove('criteria');
classInstance.room().update('criteria');
I have seen implemented something similar at shouldjs
should(10).be.a.Number();
(10).should.be.a.Number();
Updated
I have the following code:
function connectToDatabase() {
var server = orientDB(dbConfig.server);
var db = server.use(dbConfig.database);
db.on("endQuery", function onDbEndQuery() {
db.server.close();
});
return db;
}
var DbSet = function DbSet(name) {
return {
list: function list(where, select, order) {
where = where || true;
select = _.isString(select) || _.isArray(select) ? select : '*';
order = _.isString(order) || _.isArray(order) ? order : 'rid';
return connectToDatabase()
.select(select)
.from(name)
.where(where)
.order(order)
.all();
},
get: function get(where, select) {
where = where || true;
select = _.isString(select) || _.isArray(select) ? select : '*';
return connectToDatabase()
.select(select)
.from(name)
.where(where)
.all()
.then(function onResults(results) {
if (results.length > 1) {
throw new Error('multiple results');
}
return results[0];
});
},
create: function create(record) {
return connectToDatabase()
.insert()
.into(name)
.set(record)
.one();
},
update: function update(where, changes) {
where = where || true;
return connectToDatabase()
.update(name)
.set(changes)
.where(where)
.scalar();
},
remove: function remove(where) {
where = where || true;
return connectToDatabase()
.delete('VERTEX', name)
.where(where)
.scalar();
}
};
};
var db = function getDb() {
return {
room: new DbSet('Room'),
invitation: new DbSet('Invitation'),
participant: new DbSet('Participant'),
};
};
module.exports = db();
And I want to change the code be able to execute the following code:
var db=require('path/to/database');
var room = db.room.get({name:'room 1'});
var sameRoom = db.room({name:'room 1'}).get();
db.room.create({name:'second room'});
db.room({name:'second room'}).create();
//same for methods list and delete
var room = db.room.list({status:'active'});
var sameRooms = db.room({status:'active'}).list();
db.room.update({name:'second room'},{status:'inactive'});
db.room({name:'second room'}).update({status:'inactive'});
I want to be able to execute the same code for Invitation and Participant too.

We need more information as to what those functions do, but this code presents those features.
Klass = function () {};
Klass.prototype.room = function () {
....
return {
get: function () {...},
remove: function () {...},
update: function () {...}
}
};
Klass.prototype.room.get = function () {...};
classInstance = new Klass();

How to get dynamic HTML and Javascript values from a page using PhantomJS

How can I get the latest page data (HTML & Javascript varaibles) from PhantomJS
e.g page.refresh() or something?
I have an Interval, than checks a variable (on the page) every 200ms. However, this variable and the page content, isn't shown to have changed over time. (even though I know it has)
So I need an efficient way to check the value of a JS variable every 200ms or so,
then once I've discovered that variable has changed value, I want to request the latest page HTML.
How can I do this?
var Error = function (description) {
this.description = description;
return this;
};
var DTO = function (status, content, error) {
this.status = status;
this.content = content;
this.error = error;
return this;
};
function outputAndExit(dto) {
console.log(JSON.stringify(dto));
phantom.exit();
}
//For any uncaught exception, just log it out for .NET to capture
window.onerror = function (errorMsg, url, lineNumber) {
var description = 'window.onerror caught an error: ' +
'errorMsg: ' + errorMsg +
'url: ' + url +
'lineNumber: ' + lineNumber;
outputAndExit(new DTO(false, null, new Error(description)));
};
var GetDynamicPageResult__ = function () {
var obj = new GetDynamicPageResult();
obj.initialize();
return obj;
};
var GetDynamicPageResult = function () {
var self = this;
this.initialize = function () {
this.error = null;
this.isContentReadyForCrawler = false;
this.ticker = null;
this.tickerInterval = 150;
this.tickerElapsed = 0;
this.url = '';
this.loadDependencies();
this.processArgs();
this.openPage();
};
this.loadDependencies = function () {
this.system = require('system'),
this.page = require('webpage').create(),
this.page.injectJs('jquery-1.10.2.min');
this.fs = require('fs');
};
this.processArgs = function () {
if (this.system.args.length == 0) {
outputAndExit(new DTO(false, null, new Error('No arguments given')));
}
//system.args[0] Was the name of this script
this.url = this.system.args[1];
};
this.updateIsContentReadyForCrawler = function () {
var updateIsContentReadyForCrawler = self.page.evaluate(function () {
self.isContentReadyForCrawler = window.isContentReadyForCrawler;
});
};
this.openPage = function () {
self.page.open(this.url, function (status) { //NB: status = 'success' || 'fail'
if (status !== 'success') {
outputAndExit(new DTO(false, null, new Error('page.open received a non-success status')));
}
self.initTicker();
});
};
this.initTicker = function () {
this.ticker = setInterval(self.handleTick, self.tickerInterval);
};
this.handleTick = function () {
self.tickerElapsed += self.tickerInterval;
self.updateIsContentReadyForCrawler();
if (self.isContentReadyForCrawler) {
clearInterval(self.ticker);
var content = self.page.content;
self.finish(true, content, null);
} else {
var tooMuchTimeElapsed = self.tickerElapsed > 7000;
if (tooMuchTimeElapsed) {
clearInterval(self.ticker);
self.finish(false, null, new Error('Too much time elapsed'));
}
}
};
this.finish = function (status, content, error) {
content = content || '';
error = error || {};
outputAndExit(new DTO(status, content, error));
};
};
/**********************************************************************************/
/***************************** Helpers *****************************/
/**********************************************************************************/
var Utility__ = function () {
var obj = new Utility();
obj.initialize();
return obj;
};
var Utility = function () {
var self = this;
this.initialize = function () {
};
this.isEmpty = function (obj) {
var isEmpty = false;
(obj == undefined || obj == null) && (isEmpty = true);
return isEmpty;
};
this.isStringEmpty = function (str) {
var isEmpty = false;
isEmpty(str) && (isEmpty = true);
(isEmpty == false && $.trim(str) == '') && (isEmpty = true);
return isEmpty;
};
};
var getDynamicPageResult = new GetDynamicPageResult__();

I think you are almost there: you need to be using page.evaluate(), but currently only use it to get window.isContentReadyForCrawler. You need to use page.evaluate() to grab the latest HTML too.
I'm going to shamelessly paste in code from another answer (https://stackoverflow.com/a/12044474/841830):
var html = page.evaluate(function () {
var root = document.getElementsByTagName("html")[0];
var html = root ? root.outerHTML : document.body.innerHTML;
return html;
});

phonegap save an order at local file system

Hi I am using phonegap to develop a shopping app. I want to give the user an option to save their order and complete wheneven he/she finds convenient. My question where do I save the order data. Local file system or local db of the mobile device? I will like to save the order
in json format in a local file. Please suggest the best option for me. Also a snippet will be highly appreciated. Thanks

You could also use HTML5 localStorage as an easier alternative to file storage. I have been using an encapsulated version of localStorage to facilitate get/set operations and decrease namespace pollution. Please see code base below:
/**
* The class is designed to facilitate flexible permanent storage of key value
* pairs utilzing HTML5 localStorage.
*
* #class LocalMap
* #author Zorayr Khalapyan
* #version 10/25/2012
*/
var LocalMap = function ( name ) {
var that = {};
//Prevent compatability issues in different execution environments.
if ( !localStorage ) {
localStorage = {};
}
if ( !localStorage[name] ) {
localStorage[name] = "{}";
}
var setMap = function ( map ) {
localStorage[name] = JSON.stringify( map );
};
that.getMap = function () {
return JSON.parse( localStorage[name] );
};
/**
* Stores the specified (key, value) pair in the localStorage
* under the map's namespace.
*/
that.set = function ( name, object ) {
var map = that.getMap();
map[ name ] = object;
setMap( map );
};
that.get = function ( name ) {
var map = that.getMap();
return typeof( map[ name ] ) !== "undefined" ? map[name] : null;
};
that.importMap = function ( object ) {
var map = that.getMap();
var key;
for ( key in object ) {
if (object.hasOwnProperty(key)) {
map[key] = object[key];
}
}
setMap(map);
};
that.length = function () {
var map = that.getMap();
var size = 0, key;
for (key in map) {
if (map.hasOwnProperty(key)) size++;
}
return size;
};
that.erase = function () {
localStorage[name] = JSON.stringify({});
};
that.isSet = function (name) {
return that.get(name) != null;
};
that.release = function (name) {
var map = that.getMap();
if (map[name]) {
delete map[name];
}
setMap(map);
};
that.deleteNamespace = function(){
if (localStorage.hasOwnProperty(name)) {
delete localStorage[name];
}
};
return that;
};
LocalMap.destroy = function () {
for ( var item in localStorage ) {
if ( localStorage.hasOwnProperty( item ) ) {
delete localStorage[ item ];
}
}
};
LocalMap.exists = function (name) {
return (localStorage[name]) ? true : false;
};
Below are the unit tests for get and set functions:
test( "Test set()", function() {
var map = LocalMap('test-namespace');
///
map.set("var-1", "val-1");
map.set("var-2", "val-2");
map.set("var-3", "val-3");
//
ok(map.isSet("var-1"), "A variable should be successful set.");
ok(map.isSet("var-2"), "A variable should be successful set.");
ok(map.isSet("var-3"), "A variable should be successful set.");
});
test( "Test get()", function() {
var map = LocalMap('test-namespace');
map.set("var-1", "val-1");
map.set("var-2", "val-2");
map.set("var-3", "val-3");
///
var var1 = map.get("var-1");
var var2 = map.get("var-2");
var var3 = map.get("var-3");
var var4 = map.get("var-4");
//
equal(var1, "val-1", "A set variable should be succesfully retreived.");
equal(var2, "val-2", "A set variable should be succesfully retreived.");
equal(var3, "val-3", "A set variable should be succesfully retreived.");
equal(var4, null, "A variable that was not set should not be retreived.");
});
Hope this helps, and let me know if you have any questions.

How about the below code? I copied it from here. Actually I like its code.
// define dbContext & entities------------------------------------
var DemoDataContext = function () {
nova.data.DbContext.call(this, "Demo", "1.0", "Demo DB", 1000000);
this.users = new nova.data.Repository(this, User, "users");
this.roles = new nova.data.Repository(this, Role, "roles");
};
DemoDataContext.prototype = new nova.data.DbContext();
DemoDataContext.constructor = DemoDataContext;
var User = function () {
nova.data.Entity.call(this);
this.name = "";
this.password = "";
this.birthYear = 1980;
this.createdDate = new Date();
this.deleted = false;
};
User.prototype = new nova.data.Entity();
User.constructor = User;
var Role = function () {
nova.data.Entity.call(this);
this.name = "";
this.createdDate = new Date();
};
Role.prototype = new nova.data.Entity();
Role.constructor = Role;
// end define dbContext & entities------------------------------------
// service methods----------------------------------------------------
function getAllUsers(callback) {
new DemoDataContext().users.toArray(function (users) {
alert(users.length);
callback(users);
});
}
function getUserByName(name, callback) {
new DemoDataContext().users.where("name='" + name + "'").toArray(function (users) {
callback(users.firstOrDefault());
});
}
function addRole(roleName, callback) {
var role = new Role();
role.name = roleName;
var db = new DemoDataContext();
db.roles.add(role);
db.saveChanges(callback);
}
function updateUserPassword(username, password, callback) {
getUserByName(username, function (user) {
if (user == null) {
throw "no user found.";
}
user.password = password;
var db = new DemoDataContext();
db.users.update(user);
db.saveChanges(callback);
});
}
function deleteUserByName(name, callback) {
getUserByName(name, function (user) {
if (user == null) {
throw "no user found.";
}
var db = new DemoDataContext();
db.users.remove(user);
db.saveChanges(callback);
});
}
// end service methods----------------------------------------------------