module AbstractController
# In <b>routes.rb</b> one defines URL-to-controller mappings, but the reverse
# is also possible: an URL can be generated from one of your routing definitions.
# URL generation functionality is centralized in this module.
#
# See AbstractController::Routing and AbstractController::Resources for general
# information about routing and routes.rb.
#
# <b>Tip:</b> If you need to generate URLs from your models or some other place,
# then AbstractController::UrlFor is what you're looking for. Read on for
# an introduction.
#
# == URL generation from parameters
#
# As you may know, some functions - such as AbstractController::Base#url_for
# and ActionView::Helpers::UrlHelper#link_to, can generate URLs given a set
# of parameters. For example, you've probably had the chance to write code
# like this in one of your views:
#
# <%= link_to('Click here', :controller => 'users',
# :action => 'new', :message => 'Welcome!') %>
#
# #=> Generates a link to: /users/new?message=Welcome%21
#
# link_to, and all other functions that require URL generation functionality,
# actually use AbstractController::UrlFor under the hood. And in particular,
# they use the AbstractController::UrlFor#url_for method. One can generate
# the same path as the above example by using the following code:
#
# include UrlFor
# url_for(:controller => 'users',
# :action => 'new',
# :message => 'Welcome!',
# :only_path => true)
# # => "/users/new?message=Welcome%21"
#
# Notice the <tt>:only_path => true</tt> part. This is because UrlFor has no
# information about the website hostname that your Rails app is serving. So if you
# want to include the hostname as well, then you must also pass the <tt>:host</tt>
# argument:
#
# include UrlFor
# url_for(:controller => 'users',
# :action => 'new',
# :message => 'Welcome!',
# :host => 'www.example.com') # Changed this.
# # => "http://www.example.com/users/new?message=Welcome%21"
#
# By default, all controllers and views have access to a special version of url_for,
# that already knows what the current hostname is. So if you use url_for in your
# controllers or your views, then you don't need to explicitly pass the <tt>:host</tt>
# argument.
#
# For convenience reasons, mailers provide a shortcut for AbstractController::UrlFor#url_for.
# So within mailers, you only have to type 'url_for' instead of 'AbstractController::UrlFor#url_for'
# in full. However, mailers don't have hostname information, and what's why you'll still
# have to specify the <tt>:host</tt> argument when generating URLs in mailers.
#
#
# == URL generation for named routes
#
# UrlFor also allows one to access methods that have been auto-generated from
# named routes. For example, suppose that you have a 'users' resource in your
# <b>routes.rb</b>:
#
# map.resources :users
#
# This generates, among other things, the method <tt>users_path</tt>. By default,
# this method is accessible from your controllers, views and mailers. If you need
# to access this auto-generated method from other places (such as a model), then
# you can do that by including AbstractController::UrlFor in your class:
#
# class User < ActiveRecord::Base
# include AbstractController::UrlFor
#
# def base_uri
# user_path(self)
# end
# end
#
# User.find(1).base_uri # => "/users/1"
#
module UrlFor
extend ActiveSupport::Concern
included do
ActionController::Routing::Routes.install_helpers(self)
extlib_inheritable_accessor :default_url_options,
:instance_writer => false, :instance_reader => false
self.default_url_options ||= {}
end
# Overwrite to implement a number of default options that all url_for-based methods will use. The default options should come in
# the form of a hash, just like the one you would use for url_for directly. Example:
#
# def default_url_options(options)
# { :project => @project.active? ? @project.url_name : "unknown" }
# end
#
# As you can infer from the example, this is mostly useful for situations where you want to centralize dynamic decisions about the
# urls as they stem from the business domain. Please note that any individual url_for call can always override the defaults set
# by this method.
def default_url_options(options = nil)
self.class.default_url_options
end
def rewrite_options(options) #:nodoc:
if options.delete(:use_defaults) != false && (defaults = default_url_options(options))
defaults.merge(options)
else
options
end
end
# Generate a url based on the options provided, default_url_options and the
# routes defined in routes.rb. The following options are supported:
#
# * <tt>:only_path</tt> - If true, the relative url is returned. Defaults to +false+.
# * <tt>:protocol</tt> - The protocol to connect to. Defaults to 'http'.
# * <tt>:host</tt> - Specifies the host the link should be targeted at.
# If <tt>:only_path</tt> is false, this option must be
# provided either explicitly, or via +default_url_options+.
# * <tt>:port</tt> - Optionally specify the port to connect to.
# * <tt>:anchor</tt> - An anchor name to be appended to the path.
# * <tt>:skip_relative_url_root</tt> - If true, the url is not constructed using the
# +relative_url_root+ set in AbstractController::Base.relative_url_root.
# * <tt>:trailing_slash</tt> - If true, adds a trailing slash, as in "/archive/2009/"
#
# Any other key (<tt>:controller</tt>, <tt>:action</tt>, etc.) given to
# +url_for+ is forwarded to the Routes module.
#
# Examples:
#
# url_for :controller => 'tasks', :action => 'testing', :host=>'somehost.org', :port=>'8080' # => 'http://somehost.org:8080/tasks/testing'
# url_for :controller => 'tasks', :action => 'testing', :host=>'somehost.org', :anchor => 'ok', :only_path => true # => '/tasks/testing#ok'
# url_for :controller => 'tasks', :action => 'testing', :trailing_slash=>true # => 'http://somehost.org/tasks/testing/'
# url_for :controller => 'tasks', :action => 'testing', :host=>'somehost.org', :number => '33' # => 'http://somehost.org/tasks/testing?number=33'
def url_for(options = {})
options ||= {}
case options
when String
options
when Hash
_url_rewriter.rewrite(rewrite_options(options))
else
polymorphic_url(options)
end
end
protected
def _url_rewriter
ActionController::UrlRewriter
end
end
end
