How do I hide javascript code in a webpage?
I'm not sure anyone else actually addressed your question directly which is code being viewed from the browser's View Source command.
As other have said, there is no way to protect JavaScript intended to run in a browser from a determined viewer. If the browser can run it, then any determined person can view/run it also.
But, if you put your JavaScript in an external JavaScript file that is included with:
<script type="text/javascript" src="http://mydomain.example/xxxx.js"></script>
tags, then the JavaScript code won't be immediately visible with the View Source command - only the script tag itself will be visible that way. That doesn't mean that someone can't just load that external JavaScript file to see it, but you did ask how to keep it out of the browser's View Source command and this will do it.
If you wanted to really make it more work to view the source, you would do all of the following:
- Put it in an external .js file.
- Obfuscate the file so that most native variable names are replaced with short versions, so that all unneeded whitespace is removed, so it can't be read without further processing, etc...
- Dynamically include the .js file by programmatically adding script tags (like Google Analytics does). This will make it even more difficult to get to the source code from the View Source command as there will be no easy link to click on there.
- Put as much interesting logic that you want to protect on the server that you retrieve via AJAX calls rather than do local processing.
With all that said, I think you should focus on performance, reliability and making your app great. If you absolutely have to protect some algorithm, put it on the server, but other than that, compete on being the best at what you do, not by having secrets. That's ultimately how success works on the web anyway.
No, it isn't possible.
If you don't give it to the browser, then the browser doesn't have it.
If you do, then it (or an easily followed reference to it) forms part of the source.
My solution is inspired from the last comment. This is the code of invisible.html
<script src="http://code.jquery.com/jquery-1.8.2.js"></script>
<script type="text/javascript" src="invisible_debut.js" ></script>
<body>
</body>
The clear code of invisible_debut.js is:
$(document).ready(function () {
var ga = document.createElement("script"); //ga is to remember Google Analytics ;-)
ga.type = 'text/javascript';
ga.src = 'invisible.js';
ga.id = 'invisible';
document.body.appendChild(ga);
$('#invisible').remove();});
Notice that at the end I'm removing the created script. invisible.js is:
$(document).ready(function(){
alert('try to find in the source the js script which did this alert!');
document.write('It disappeared, my dear!');});
invisible.js doesn't appear in the console, because it has been removed and never in the source code because created by javascript.
Concerning invisible_debut.js, I obfuscated it, which means that it is very complicated to find the url of invisible.js. Not perfect, but enought hard for a normal hacker.