Securely importing contents of a protected js-file by using AJAX - php

Question

To import a js-file is simple... just use >script src='file.js' type='text/javascript'>>/script>.
But then the source code will show a direct url to the contents of the file.
The content should be executable, but not directly viewable by using source url.
What is the best way to load the content of file.js to memory using AJAX.
I've come to the following initial way of working (just and idea, totally flawed?):
function get_contents() {
-> ajax execute PHP {copy 'file.js' to 'token.js' in tmp-directory}
-> ajax get contents of 'tmp/token.js' and load to memory
-> ajax execute PHP {delete 'tmp/token.js' in tmp-directory}
return(true); // content (ie. functions) should now be usable
}
But I'm not sure if the second ajax excute is enough to now be able to succesfully call the functions.
PHP returns content, but javascript 'ajax success' may see it (and stores it) as an variable... doh!
Is this ajax success idea going to work ??
Can someone suggest a better idea ?
Edit:
According to initial responses this way of working is virtually and humanly impossible.
Will solve it by loading common functions the 'normal' unprotected way, and using Jerry's suggestion (see comment) for calculations that happen less often.
Edit #2:
Below mentioned (time consuming) problem can be solved by following next template.
Still making use of the suggested 'hidden PHP code' method.
I am making use of a buffer (or sumthing), like a Youtube video... except 'video data' is 'results from AJAX-PHP functions'.
AJAX request "30 cycle", "60 cycle", "300 cycle", "600 cycle"
store result to buffer
initiate "start cycle"
function cycle() // run every second !!
{
//do stuff... no AJAX needed
//do some more stuff... like animations and small calculations
//per 30 cycle (30 seconds)
if ($cycle==30)
{
perform last "30 cycle" AJAX result [PHP-function set "A"]
... when finished: AJAX request "30 cycle"
store result to buffer in 'background'
}
//per 60 cycle (1 minute)
if ($cycle==60)
{
perform last "60 cycle" AJAX result [PHP-function set "B"]
... when finished: AJAX request "60 cycle"
store result to buffer in 'background'
}
//and so on....
}
Initial question 99% solved (-1 because of developer tools).
Thanks for commenting and suggestions.

Answer 1

Even if you split up your JavaScript files into lots of individual functions it would take very little work to put it all back together again.
With modern browsers even a file is "loaded into memory" you can see exactly what was loaded.
Try using the developer tools that come with browsers, you can use them to see when an Ajax call is made, exactly what was loaded in text format.
If you are mixing PHP and JavaScript then you should put anything that is sensitive in your PHP code whilst using JavaScript for your presentation of the results PHP provides.
EDIT: as per your update, instead of doing "cycles" could you not do this?
function pollAjax()
{
$.ajax({
-- ajax settings --
}).success(function(data) {
// do something with our results
doSomething(data);
// Fire again to get the next set of results.
setTimeout(function() {pollAjax()}, 10);
});
}
This means you're less likely to hang the browser with 1000's of pending ajax requests It will ask for the results, when it gets them, it will ask for the next set of results.