Advanced Rails - Building Industrial-Strength Web Apps in Record Time

86 | Chapter 3: Rails Plugins

class ApplicationController < ActionController::Base

include AccountLocation

end

puts ApplicationController.instance_methods.grep /^account/

=> ["account_domain", "account_subdomain", "account_host", "account_url"]

Including theAccountLocationmodule in the controller allows you to access various
URL options from the controller and the view. For example, to set the@accountvari-
able from the subdomain on each request:

class ApplicationController < ActionController::Base

include AccountLocation

before_filter :find_account

protected

def find_account

@account = Account.find_by_username(account_subdomain)

end

end

Theaccount_locationplugin has noinit.rb; nothing needs to be set up on load, as all
functionality is encapsulated in theAccountLocationmodule. Here is the implemen-
tation, inlib/account_location.rb (minus some license text):

module AccountLocation

def self.included(controller)

controller.helper_method(:account_domain, :account_subdomain,

:account_host, :account_url)

end

protected

def default_account_subdomain

@account.username if @account && @account.respond_to?(:username)

end

def account_url(account_subdomain = default_account_subdomain,

use_ssl = request.ssl?)

(use_ssl? "https://" : "http://") + account_host(account_subdomain)

end

def account_host(account_subdomain = default_account_subdomain)

account_host = ""

account_host << account_subdomain + "."

account_host << account_domain

end

def account_domain

account_domain = ""

account_domain << request.subdomains[1..-1].join(".") +

"." if request.subdomains.size > 1

account_domain << request.domain + request.port_string

end