Submarine

Submarine was built upon DHH's Account Location plugin. It gives you a set of protected methods that use the subdomain as a way of identifying the current scope. These methods allow you to easily produce URLs that match this style and to get the current subdomain from a request. Submarine includes support for subdomains in a development environment running on localhost.

• Edit /etc/hosts by adding your aliases after the localhost (on the same line):

127.0.0.1     localhost foo.localhost bar.localhost

• Then you must clear the cached DNS entries:

sudo dscacheutil -flushcache

• Include Submarine in one of your controllers or just once in the application controller:

class ApplicationController < ActionController::Base
   include Submarine
end

• Submarine will generate the following helper methods (using the default settings): user_url, user_host, user_domain. It will also provide you a method to retrieve the current request's subdomain: current_subdomain

• By default, all helper methods will query @user.login (hi restufl_authentication) when generating the subdomain part. You can set these attributes by overwriting the subdomain_model and subdomain_column methods in your controller after including the module:

class ApplicationController < ActionController::Base
   include Submarine
   
   def subdomain_model
      'account'
   end
   
   def subdomain_column
      'name'
   end
end

• Doing so will grant you a new set of helper methods, prepending the subdomain_model instead of 'user' (using the example above): account_url, account_host, account_domain

• If you pass along a string as a parameter to the helper methods, these will use it for the subdomain part of the URL's.

@account.name
=> 'quack'

account_url
=> 'http://quack.domain.com'

account_url('moo')
=> 'http://moo.domain.com'

You have a domain that hosts several blogs and you wish to shorten their URL from http://www.domain.com/blogs/fooblog/posts to http://fooblog.domain.com/

class ApplicationController < ActionController::Base
   include Submarine
end

def PostsController < ApplicationController	
	before_filter :load_blog
	
	def subdomain_model; 'blog' end
	def subdomain_column; 'name' end
	
	def index
		@posts = @blog.posts
	end
	
protected

	def load_blog
		@blog = Blog.find_by_name(current_subdomain)
	end
end

If you want to link to each of your blogs when the users visit your domain, you can use the helper methods in your views

<div class="sidebar">
    <ul>
    <% @blogs.each do |blog| %>
		<li><%= blog_url(blog.name) %></li>
	<% end %>
    </ul>
</div>

• Use method_missing instead of method_alias for the model name based helpers.
• Helper method tests
• Add subdomain based routing support

Copyright (c) 2008 Norbauer Inc, released under the MIT license
Written by Jose Fernandez with support from Norbauer Inc.