Are external javascript libraries hidden?

Question

So I realize that anyone can view the javascript in-line with HTML running in their browser, so if I use an external js library on my server will its contents be completely hidden?

Another question is are there any cases where it's better to use in-line javascript, like with jQuery or something, or is there really no down side to just using a js library for all of it?

Answer 1

No, there is no way that your javascript will ever be "hidden". Anything that can be run in a browser can be trivially saved and inspected. The best you can do is use an obfuscator.

The downside to using an external file is that it's another request. The upside is that it can be cached independently. For best performance, code that will be used from more than one page should be stored in its own file, and code that is page-specific is better off being stored within the page that uses it.

Answer 2

JavaScript operates on the Browser level, that means that the browser at some point read your JS (external or internal same s.). You can easily conclude from this that if at some point the JS is now registered by the browser, and it's accessible by anyone with a bit more knowledge in web stuff. you'll not be able to hide your JS trickery.
Pus inside your JS a Copyright notice and pray.

Never send sensitive data through the yellow wire .
If you have some extra sensitive strings, encode and compare them on server side - sending them like MD5 or in some SHA model to the server.

Answer 3

Javascript, with the exception of something like node, operates client-side so you can't really use an "external js library" on your server, whatever that means.

Best practices dictate that you should almost always reference your javascript using <script> tags and link to your javascript file using the src attribute.