Where does RAILS_ROOT (Rails.root) come from? - ruby

Question

I have a ruby on rails application that is located at /home/user/application. I have a Apache webserver whose DocumentRoot is /var/www. And I have a symlink /var/www/application -> /home/user/application.
My apache configuration section that concerns the ruby on rails is the following:
RailsBaseURI /application
<Directory /home/user/application>
Order Allow,Deny
Allow from all
Options -MultiViews
</Directory>
I modified the Passenger code so in the very beginning of it spawning it would print (to a file) the option app_root. If it matters, I modified the file phusion_passenger/spawn_manager.rb in the method handle_spawn_application.
The value that I get is /home/user and this is wrong, I needed /home/user/application. So my question is, how does Passenger figures out the option['app_root'] (which becomes RAILS_ROOT|Rails.Root)?
Observation: I modified the Passenger code to hardcode app_root to /home/user/application and everything worked fine.

Answer 1

Change the symlink so that /var/www/application points to /home/user/application/public
Then just change RailsBaseURI to RackBaseURI and undo your changes to spawn_manager.rb
Previous discussion assumed single application.
<Directory /var/www/application/public>
Order Allow,Deny
Allow from all
Options -MultiViews
</Directory>
See the Apache Phusion documentation.
You need to add DocumentRoot and append /public to your Directory config and undo your changes to spawn_manager.rb.
As you noticed, the app_root is one directory up from what is specified.. The parent directory of /home/user/application/public is /home/user/application which is the Rails root.
You want RackBaseURI instead of RailsBaseURI for Rails > 3
The reasoning behind this is so that Apache serves the static assets (which are in the public directory) and then if that isn't present Passenger routes the request to the Rails app.