how could I hack url helper/route helper to make all paths add prefix

Question

I want to make all generated URLs can start with /sample_1/ as its prefix.

Because the server is running under subfolder,

how could I do on Rails 4.2.4 ? The following routes rules don't generate all paths with the prefix.

I couldn't find any workable solution by Google

routes.rb

Rails.application.routes.draw do

  sample_1 = Proc.new do
      root 'welcome#category'
  end

  if ENV['RAILS_RELATIVE_URL_ROOT']
    scope ENV['RAILS_RELATIVE_URL_ROOT'] do
      sample_1.call
    end
  else
    sample_1.call
  end

end

Application.rb

module Sample
  class Application < Rails::Application

    config.active_record.raise_in_transactional_callbacks = true
    config.middleware.use Rack::Deflater
    config.relative_url_root = ENV['RAILS_RELATIVE_URL_ROOT']
  end
end

nginx , the root URL runs flask web server not rails

    location /sample_1/ {
        rewrite ^/sample_1/(.*)$ /$1 break;
        proxy_set_header   X-Real-IP        $remote_addr;
        proxy_set_header   X-Forwarded-For  $proxy_add_x_forwarded_for;
        proxy_set_header   Host $http_host;
        proxy_pass http://127.0.0.1:8512;
    }

    location / {
            proxy_pass http://localhost:8006;

            proxy_set_header X-Real-IP $remote_addr;
            proxy_set_header Host $host;
            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
    }

Answer 1

did you try to prefix using :as with scope:

scope "admin", :as => "admin" do
  resources :photos, :accounts
end

resources :photos, :accounts

This will generate routes such as admin_photos_path and admin_accounts_path which map to /admin/photos and /admin/accounts respectively.

:as Prefixes the routing helpers in this scope with the specified label.

  scope :as => "sekret" do
    resources :posts
  end

Answer 2

Since the built in Rails relative_url_root option does not seem to work, you can use a workaround:

Rails.application.routes.draw do
  # Bad hack because relative_url_root does not work.
  # @fixme, @todo
  scope ENV['MYAPP_RELATIVE_URL_ROOT'] do
   root 'welcome#category'
  end
end

Calling scope nil actually does nothing to the resulting routes so you can simplify quite a bit.

$ rake routes MYAPP_RELATIVE_URL_ROOT=foo
Prefix Verb URI Pattern    Controller#Action
  root GET  /foo(.:format) welcome#category

I would not use RAILS_RELATIVE_URL_ROOT in the workaround since your app will unexpectedly break if the behavior is fixed in future Rails release. So a safe approach is to leave RAILS_RELATIVE_URL_ROOT unset until you know it is fixed and then remove the hack.

Edited.

It does work. You are most likely doing something else wrong.

1. git clone https://github.com/maxcal/sandbox/tree/33344204
2. cd sandbox
3. bundle install
4. MYAPP_RELATIVE_URL_ROOT=test rails s
5. open localhost:3000/test in your browser.

How you actually set ENV vars depends on your shell. The above works for Bash/Zsh. I'm guessing that this is where you are failing.

Answer 3

The Rails docs say you can use a scope:

#config/routes.rb
def method
   root "....."
   resources :controller_1, :controller_2
end

if .......
   scope :prefix_1 do
      method
   end
else
   method
end

---

Because the server is running under subfolder

This should not be a problem for Rails.

If you want the app in a subfolder, it's under the duress of your web server software to route it.

Here's an example with nginx:

server {
   listen 80;
   server_name your_folder.com;
   root /your/app/destination/folder;

This means if you stick to using the _path helpers (not _url), it will keep all the relative paths working properly.