Develop Reference

jquery load to hide content

There is javascript on my webpage, but I need to hide it from my users (I don't want them to be able to see it because it contains some answers to the game.)
So I tried using Jquery .load in order to hide the content (I load the content from an external js file with that call). But it failed to load. So I tried ajax and it failed too.
Maybe the problem comes from the fact that I'm trying to load a file located in my root directory, while the original page is located in "root/public_html/main/pages":
<script type="text/javascript">
$(document).ready(function() {
$.ajax({
url : "../../../secret_code.js",
dataType: "text",
success : function (data) {
$("#ajaxcontent").html(data);
}
});
});
</script>
1) Why can't I load a file from the root directory with ajax or load method?
2) Is there another way around?
PS: I'm putting the file in the root directory so people can't access it directly from their browsers...

1) if the file isn't accessible via web browsers, than it's not accessible via ajax (ajax is part of the web browsers
2) try /secret_code instead of ../../../secret_code.js

What is your system setup? Are you using a CMS?
Even if you add the javascript to the page after page load a user with a tool like firebug can go and view it. I don't think what you are doing is really going to secure it. An alternate solution is that you could minify and obfuscate the javascript that you use in your production environment. This will produce near unreadable but functioning javascript code. There are a number of tools that you can run your code through to minify and obfuscate it. Here is one tool you could use: http://www.refresh-sf.com/yui/
If that isn't enough then maybe you could put the answers to the game on your serverside and pull them via ajax. I don't know your setup so I don't know if that is viable for you.

Navigate to the URL, not the directory. Like
$.ajax({
url : "http://domain.com/js/secret_code.js",
..

Even if you load your content dynamicly, it's quite easy to see content of the file using firebug, fiddler or any kind of proxy. I suggest you to use obfuscator. It will be harder for user to find answer

Take a look at the jQuery.getScript() function, it's designed for loading Javascript files over AJAX and should do what you need.

Try jQuery's $.getScript() method for loading external
Script files, however, you can easily see the contents of the script file using Firebug or the developer toolbar!

Security first
You can't access your root directory with JavaScript because people would read out your database passwords, ftp password aso. if that would be possible.

You can only load files that are accessible directly from browsers, for example, http://www.mydomain.com/secret_code.js
If it can't be accessed directly by the browser, it can't be accessed by the browser via ajax. You can however use .htaccess to prevent users from opening up a js file directly, though that doesn't keep them from looking at it in the google chrome or firebug consoles.
If you want to keep it secret, don't let it get to the browser.

How to capture a complete webpage using javascript

I inject javascript code into a page user is currently viewing, on users command this script make DOM changes. At the end of this interaction user might want to save the page so that s/he can view/edit it later. I could remember the DOM changes that user made, But if the original page(at its source) is changed, I will not be able to restore this page for user. That is why I want to send the changed page to my server. I should be able to restore it completely and the page should behave exactly the way it did(including scripts and media).
Additionally I can not store media of users page at my end(resource limitation), so I guess I have to parse and modify all addresses/references/links of media to global URL/URI in various scripts(HTML/CSS/JavaScript).
Now the question is, Is there a library/framework/jquery extension that can help me achieve this objective ?
else, What is the right/professional way to do it ?

Since you are using jQuery you could try $("html").html(); just make sure to add the appropriate <html> tags when you output it again.

$('body').html()
$('head').html()
$('html').html()
Download firebug, and try it in the console window on this page. I am getting what looks like the correct data back.

Have I got It right that you are building some kind of CMS that let's the user edit entire pages (Not just seperate content blocks) in Contenteditable mode?
I would definatly advise looking at a solution like ckeditor/tinymce etc... Because doing it all yourself will be a terrible pain.

The answer from #Sydenam should work fine to save the whole HTML page.
Meanwhile, and this is IMPORTANT, I would recommend you to consider a potential SECURITY ISSUE here. Indeed the user can inject whatever he wants in the DOM and have you saving it, like nasty Javascript functions sending confidential information on a remote server for example.
So, in my perspective, a professional way of doing this would be to dedicate a PART of the DOM only to that usage, let say a <div id='editable_div'> that you can load using a $('#editable_div').load('your_url',parameters, etc...), and save afterward using another AJAX call.
When saving it you can parse this chunk of HTML and make sure nothing nasty is inside with some regexp (like tags).
Hope it helps,
Regards,

How do I protect JavaScript files?

I know it's impossible to hide source code but, for example, if I have to link a JavaScript file from my CDN to a web page and I don't want the people to know the location and/or content of this script, is this possible?
For example, to link a script from a website, we use:
<script type="text/javascript" src="http://somedomain.example/scriptxyz.js">
</script>
Now, is possible to hide from the user where the script comes from, or hide the script content and still use it on a web page?
For example, by saving it in my private CDN that needs password to access files, would that work? If not, what would work to get what I want?

Good question with a simple answer: you can't!
JavaScript is a client-side programming language, therefore it works on the client's machine, so you can't actually hide anything from the client.
Obfuscating your code is a good solution, but it's not enough, because, although it is hard, someone could decipher your code and "steal" your script.
There are a few ways of making your code hard to be stolen, but as I said nothing is bullet-proof.
Off the top of my head, one idea is to restrict access to your external js files from outside the page you embed your code in. In that case, if you have
<script type="text/javascript" src="myJs.js"></script>
and someone tries to access the myJs.js file in browser, he shouldn't be granted any access to the script source.
For example, if your page is written in PHP, you can include the script via the include function and let the script decide if it's safe" to return it's source.
In this example, you'll need the external "js" (written in PHP) file myJs.php:
<?php
$URL = $_SERVER['SERVER_NAME'].$_SERVER['REQUEST_URI'];
if ($URL != "my-domain.example/my-page.php")
die("/\*sry, no acces rights\*/");
?>
// your obfuscated script goes here
that would be included in your main page my-page.php:
<script type="text/javascript">
<?php include "myJs.php"; ?>;
</script>
This way, only the browser could see the js file contents.
Another interesting idea is that at the end of your script, you delete the contents of your dom script element, so that after the browser evaluates your code, the code disappears:
<script id="erasable" type="text/javascript">
//your code goes here
document.getElementById('erasable').innerHTML = "";
</script>
These are all just simple hacks that cannot, and I can't stress this enough: cannot, fully protect your js code, but they can sure piss off someone who is trying to "steal" your code.
Update:
I recently came across a very interesting article written by Patrick Weid on how to hide your js code, and he reveals a different approach: you can encode your source code into an image! Sure, that's not bullet proof either, but it's another fence that you could build around your code.
The idea behind this approach is that most browsers can use the canvas element to do pixel manipulation on images. And since the canvas pixel is represented by 4 values (rgba), each pixel can have a value in the range of 0-255. That means that you can store a character (actual it's ascii code) in every pixel. The rest of the encoding/decoding is trivial.

The only thing you can do is obfuscate your code to make it more difficult to read. No matter what you do, if you want the javascript to execute in their browser they'll have to have the code.

Just off the top of my head, you could do something like this (if you can create server-side scripts, which it sounds like you can):
Instead of loading the script like normal, send an AJAX request to a PHP page (it could be anything; I just use it myself). Have the PHP locate the file (maybe on a non-public part of the server), open it with file_get_contents, and return (read: echo) the contents as a string.
When this string returns to the JavaScript, have it create a new script tag, populate its innerHTML with the code you just received, and attach the tag to the page. (You might have trouble with this; innerHTML may not be what you need, but you can experiment.)
If you do this a lot, you might even want to set up a PHP page that accepts a GET variable with the script's name, so that you can dynamically grab different scripts using the same PHP. (Maybe you could use POST instead, to make it just a little harder for other people to see what you're doing. I don't know.)
EDIT: I thought you were only trying to hide the location of the script. This obviously wouldn't help much if you're trying to hide the script itself.

Google Closure Compiler, YUI compressor, Minify, /Packer/... etc, are options for compressing/obfuscating your JS codes. But none of them can help you from hiding your code from the users.
Anyone with decent knowledge can easily decode/de-obfuscate your code using tools like JS Beautifier. You name it.
So the answer is, you can always make your code harder to read/decode, but for sure there is no way to hide.

Forget it, this is not doable.
No matter what you try it will not work. All a user needs to do to discover your code and it's location is to look in the net tab in firebug or use fiddler to see what requests are being made.

From my knowledge, this is not possible.
Your browser has to have access to JS files to be able to execute them. If the browser has access, then browser's user also has access.
If you password protect your JS files, then the browser won't be able to access them, defeating the purpose of having JS in the first place.

I think the only way is to put required data on the server and allow only logged-in user to access the data as required (you can also make some calculations server side). This wont protect your javascript code but make it unoperatable without the server side code

I agree with everyone else here: With JS on the client, the cat is out of the bag and there is nothing completely foolproof that can be done.
Having said that; in some cases I do this to put some hurdles in the way of those who want to take a look at the code. This is how the algorithm works (roughly)
The server creates 3 hashed and salted values. One for the current timestamp, and the other two for each of the next 2 seconds. These values are sent over to the client via Ajax to the client as a comma delimited string; from my PHP module. In some cases, I think you can hard-bake these values into a script section of HTML when the page is formed, and delete that script tag once the use of the hashes is over The server is CORS protected and does all the usual SERVER_NAME etc check (which is not much of a protection but at least provides some modicum of resistance to script kiddies).
Also it would be nice, if the the server checks if there was indeed an authenticated user's client doing this
The client then sends the same 3 hashed values back to the server thru an ajax call to fetch the actual JS that I need. The server checks the hashes against the current time stamp there... The three values ensure that the data is being sent within the 3 second window to account for latency between the browser and the server
The server needs to be convinced that one of the hashes is
matched correctly; and if so it would send over the crucial JS back
to the client. This is a simple, crude "One time use Password"
without the need for any database at the back end.
This means, that any hacker has only the 3 second window period since the generation of the first set of hashes to get to the actual JS code.
The entire client code can be inside an IIFE function so some of the variables inside the client are even more harder to read from the Inspector console
This is not any deep solution: A determined hacker can register, get an account and then ask the server to generate the first three hashes; by doing tricks to go around Ajax and CORS; and then make the client perform the second call to get to the actual code -- but it is a reasonable amount of work.
Moreover, if the Salt used by the server is based on the login credentials; the server may be able to detect who is that user who tried to retreive the sensitive JS (The server needs to do some more additional work regarding the behaviour of the user AFTER the sensitive JS was retreived, and block the person if the person, say for example, did not do some other activity which was expected)
An old, crude version of this was done for a hackathon here: http://planwithin.com/demo/tadr.html That wil not work in case the server detects too much latency, and it goes beyond the 3 second window period

As I said in the comment I left on gion_13 answer before (please read), you really can't. Not with javascript.
If you don't want the code to be available client-side (= stealable without great efforts),
my suggestion would be to make use of PHP (ASP,Python,Perl,Ruby,JSP + Java-Servlets) that is processed server-side and only the results of the computation/code execution are served to the user. Or, if you prefer, even Flash or a Java-Applet that let client-side computation/code execution but are compiled and thus harder to reverse-engine (not impossible thus).
Just my 2 cents.

You can also set up a mime type for application/JavaScript to run as PHP, .NET, Java, or whatever language you're using. I've done this for dynamic CSS files in the past.

I know that this is the wrong time to be answering this question but i just thought of something
i know it might be stressful but atleast it might still work
Now the trick is to create a lot of server side encoding scripts, they have to be decodable(for example a script that replaces all vowels with numbers and add the letter 'a' to every consonant so that the word 'bat' becomes ba1ta) then create a script that will randomize between the encoding scripts and create a cookie with the name of the encoding script being used (quick tip: try not to use the actual name of the encoding script for the cookie for example if our cookie is name 'encoding_script_being_used' and the randomizing script chooses an encoding script named MD10 try not to use MD10 as the value of the cookie but 'encoding_script4567656' just to prevent guessing) then after the cookie has been created another script will check for the cookie named 'encoding_script_being_used' and get the value, then it will determine what encoding script is being used.
Now the reason for randomizing between the encoding scripts was that the server side language will randomize which script to use to decode your javascript.js and then create a session or cookie to know which encoding scripts was used
then the server side language will also encode your javascript .js and put it as a cookie
so now let me summarize with an example
PHP randomizes between a list of encoding scripts and encrypts javascript.js then it create a cookie telling the client side language which encoding script was used then client side language decodes the javascript.js cookie(which is obviously encoded)
so people can't steal your code
but i would not advise this because
it is a long process
It is too stressful

use nwjs i think helpful it can compile to bin then you can use it to make win,mac and linux application

This method partially works if you do not want to expose the most sensible part of your algorithm.
Create WebAssembly modules (.wasm), import them, and expose only your JS, etc... workflow. In this way the algorithm is protected since it is extremely difficult to revert assembly code into a more human readable format.
After having produced the wasm module and imported correclty, you can use your code as you normallt do:
<body id="wasm-example">
<script type="module">
import init from "./pkg/glue_code.js";
init().then(() => {
console.log("WASM Loaded");
});
</script>
</body>

What is a "?" for in the src attribute of a html script tag?

If this has been asked before, I apologize but this is kinda of a hard question to search for. This is the first time I have come across this in all my years of web development, so I'm pretty curious.
I am editing some HTML files for a website, and I have noticed that in the src attribute of the script tags that the previous author appended a question mark followed by data.
Ex: <script src="./js/somefile.js?version=3.2"></script>
I know that this is used in some languages for value passing in GET request, such as PHP, but as I far as I ever knew, this wasn't done in javascript - at least in calling a javascript file. Does anyone know what this does, if anything?
EDIT: Wow, a lot of responses. Thanks one and all. And since a lot of people are saying similar things, I will post an global update instead of commenting everyone.
In this case the javascript files are static, hence my curiosity. I have also opened them up and did not see anything attempt to access variables on file load. I've never thought about caching or plain version control, both which seam more likely in this circumstance.

I believe what the author was doing was ensuring that if he creates version 3.3 of his script he can change the version= in the url of the script to ensure that users download the new file instead of running off of the old script cached in their browser.
So in this case it is part of the caching strategy.

My guess is it's so if he publishes a new version of the JavaScript file, he can bump the version in the HTML documents. This will not do anything server-side when requested, but it causes the browser to treat it as a different file, effectively forcing the browser to re-fetch the script and bypass the local cache of the file.
This way, you can set a really high cache time (like a week or a month!) but not sacrifice the ability to update scripts frequently if necessary.

What you have to remember is that this ./js/somefile.js?version=3.2 doesn't have to be a physical file. It can be a page which creates the file on the fly. So you could have it where the request says, "Hey give me version 3 of this js file," and the server side code creates it and writes it to the output stream.
The other option is to force the browser to not cache the file and pull down the new one when it makes the request. Since the URI changed, it will think the file is completely new.

A (well-configured) web server will send static files like JavaScript source code once and tell the web browser to cache that file locally for a certain period of time (could be a day, a week, a month, or longer). When the browser sees another request for that same file, it will just use that version instead of getting new code from the server.
If the URL changes -- for example by adding a query string -- then the browser suspects that its cached version is no good and gets a new one. As such, the ? helps developers say "Oops, I changed this file, make sure the browser gets a new copy."

In this case it's probably being used to ensure the source file isn't cached between versions.
Of course, it could also be used server side to generate the javascript file, without knowing what you have on the other end of the request, it's difficult to be definitive.
BTW, the ?... portion of the url is called the query string.

this is used to guarantee that the browser downloads a new version of the script when available. The version number in the url is incremented each time a new version is deployed so that the browser see it as a different file.

Just because the file extension is .js doesn't mean that the target is an actual .js file. They could set up their web server to pass the requested URL to a script (or literally have a script named somefile.js) and have that interpret the filename and version.

The query string has nothing to do with the javascript. Some server side code is hosting up a different version depending on that querystring it appears.
You should never assume anything about paths in a URL. The extension on a path in a URL doesn't really tell you anything. URLs can be completely dynamic and served by some server side code or can rewritten in web servers dynamically.
Now it is common to add a querystring to urls when loading javascript files to prevent client side caching. If the page updates and references a new version of the script then the page can bust through and cause the client to refresh it's script.

Ajax Parsing Local XML

I'm building a local html file to show dynamically some data from an XML file and by using Chrome's Inspector I figured my XML file is not being parsed because it is "not hosted on a webserver"
XMLHttpRequest cannot load data.xml. Cross origin requests are only supported for HTTP.
I know that there are a few flags I could pass to Chrome/web browser to workaround this limitation but I'm looking into some alternative method. I will probably have to distribute this files to a few people and teaching them how to pass flags to the browser is not an option for me. Hosting them on a web server is not an option either.
Thanks a lot in advance.

No ghost unless you set up a local server or host the XML file locally. Ajax has to follow the same origin policy.

If you're willing to use a library you can use jQuery's AJAX method to perform a cross-domain request (i'm not entirely certain that jQuery will support what you're trying to do). JSONP works, but you have XML data...
You could try loading it in a script tag anyway and see if you can get the innerHTML value without breaking the script; once you're done getting the text from it, remove the script from the page. You may be able to get at the data before the browser tries to parse the script by attaching onload and onreadystatechange events to the script element.
var s = document.createElement('script');
s.src = '/path/to/file.xml';
s.onload = s.onreadystatechange = getData;
function getData(e)
{
//get the text out of the script element
//remove the event handler from the script element
//remove the script from the page
}
document.getElementsByTagName('body')[0].appendChild(s);
I didn't test it, but it might work.

How about setting up a local webserver? XAMPP should be easy to install even for novice. Just tell them to put your files in the htdocs folder, run xampp and start the apache server.

Unless there's a compelling reason to have a separate html and xml file, you could just put the data directly in the html file.

I'm afraid if chrome only provides options that you don't like to apply, your application and chrome will not come together. Access via iframe & object does'nt work too, load()-method of createDocument is not supported by chrome(if it does I guess you got the same error).
Whatever you try will be a sideway to pass chrome's restrictions, what cannot be good, because I think they have good reasons to setup these restrictions.