How to config subdirectory with Rails + Nginx + Unicorn?

This article mainly focuses on how to run the rails app in a subdirectory using NGINX. You will learn the reverse proxy of Nginx to serve your rails app.

It was needed because I came to meet a problem in which I want to run a specific part of a website in Ruby on Rails for a specific subdirectory.  For example, my website is in PHP www.myphpwebsite.com/ and I want to run Ruby on rails site on the same url with different subdirectories like www.myphpwebsite.com/runthisinrubyonrails/. Whenever /runthisinrubyonrails/ detected, It should run on a different servers which is running   ROR.

Configuration in a rails app.

Rails give us a simple configuration for this purpose.

In config/application.rb file, add the following code:

module YourAPPName
 class Application < Rails::Application
   config.relative_url_root = '/runthisinrubyonrails'
   # some other configuration code
 end
end

In config.ru file:

map Rails::Application.config.relative_url_root || "/" do
 run Rails.Application
end

Test everything works fine

we can check everything works fine with click route with /runthisinrubyonrails/ and simple by /.

for example, first asset was getting by www.myphpwebiste.com/assets/favicon.ico now you can try with www.myphpwebsite.com/runthisinrubyonrails/assets/favicon.ico. Both should work because when we have defined that in our config.ru file

Rails::Application.config.relative_url_root || "/"

if relative_url_root found then try with that if not then try with “/”

Nginx Configuration

So we have the following configuration:

upstream unicorn_sock {
 server your_sock_path;
}

server {
root <path_to_your_rails_app>/public;
location @proxy_rails_app {
 proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
 proxy_set_header Host $http_host;
 proxy_redirect off;
 proxy_pass http://unicorn_sock;
}
location /runthisinrubyonrails/ {
 alias <path_to_your_rails_app>/public/;
 try_files $uri @proxy_rails_app;
}
try_files $uri @proxy_rails_app;
# some other configuration code
}