RAL will give you the ability to search for asset paths in plain javascript.
Add rails-assets.org source to your Gemfile
:
source 'http://rails-assets.org'
And then behave like normal:
gem 'rails-assets-localization'
$.localization('/assets/<YOUR_APP>/locales/en/translation.json');
// or
$.localization('<YOUR_APP>/locales/en/translation.json');
You can enable debugging by passing a boolean parameter:
$.localization('<YOUR_APP>/locales/en/translation.json', true);