Rails::LocalSubdomain

Rails localhost subdomain support.

Rails::LocalSubdomain enables the developer access to routes within a Rails subdomain (e.g. testing, Q.A.). It should work out of the box.

Almost all of the work was completed by https://github.com/manuelvanrijn (https://github.com/manuelvanrijn/local-subdomain). I only wanted to add the ability to configure which environments will have Rails subdomain support. Specifically, I was trying to test a Rails application via Capybara and had to modify the original gem source to let us access subdomains during tests.

1. Add the gem to your Gemfile, preferably outside of any group.

gem 'rails-local_subdomain', group: :test # bad

gem 'rails-local_subdomain' # good

2. Run bundle install
3. Include the Rails::LocalSubdomain module into a controller (usually ApplicationController)

require 'rails/local_subdomain'

class ApplicationController < ActionController::Base
  include Rails::LocalSubdomain
  ....
end

Subdomains should now be accessible in all Rails environments white listed in Rails::LocalSubdomain.enabled_environments.

Configuration can be easily done via Rails initializers, simply monkey-patch in whatever values you wish to customize:

# ./config/initializers/rails/local_subdomain.rb

module Rails
  module LocalSubdomain
    def self.enabled_environments
      %w(develop test)
    end
  end
end

Rails::LocalSubdomain monkey-patches Rack::Handler to bind to 0.0.0.0 rather than localhost.

By default, this gem uses the domain http://lvh.me to handle our requests for our subdomain(s). Request to the domain lvh.me redirects all requests to 127.0.0.1.

This give's us the ability to browse to http://subdomain.lvh.me:3000 and handle request.subdomain from our controllers.

Because we're going to use the external domain http://lvh.me which redirects to 127.0.0.1 we have to make our server not to bind to localhost only.

This module includes a before_action which will check if the request is served by http://lvh.me. If not it will redirect to the domain.

So when we browse to http://localhost:3000 it will redirect you to http://lvh.me:3000

I've tested the gem with:

• WEBrick
• Puma
• Thin

Thanks to https://github.com/manuelvanrijn/local-subdomain for coming up with the original gem. It's helped my development a lot!