Rails root_path in application.js

Question

How can I get my hands on the project's root_path in my application.js file?

I need it for a js plugin ( codemirror ) that needs to load other JS files. It's all fine and dandy if I say "/javascripts/needed_file.js", but what if I deploy my project to "/custom".

The code needs to do its magic all over the project and I would like it to be UJS, so it needs to be in a static javascript file.

Any solutions/simple hacks?

Answer 1

There's no beautiful solution. I'd try one of these approaches:

• Inspect window.location.pathname . Determine from this whether running from root or from a prefix url.

• Add something like <script type="text/javascript" charset="utf-8">var ROOT_PATH = '<%= Rails.root_path %>';</script> somewhere to the top of your layout file.

• Use this quite hackish function (I suspect that it might break with some of the HTML5 script attributes):

   function urlOfCurrentFile() { var scripts = document.getElementsByTagName("script"); return scripts[scripts.length - 1].src; } 

Answer 2

I have this in my header file.

<script type="text/javascript">
  var BASE_URL = '<%= root_url %>';
</script>

Answer 3

Well, the best way I find is to leverage the power of JS to do so, like:

window.location.origin # http://localhost:3000/

It's gonna give you the complete hostname, with http:// , and the port number. Like in case of running Rails server locally, it will give you: http://localhost:3000

window.location.hostname # localhost

It's just gonna give you the name of host, and nothing about port or HTTP. Incase of Rails server running locally, it will give you: localhost .