module ActionController
# == Overview
#
# ActionController::Resources are a way of defining RESTful resources. A RESTful resource, in basic terms,
# is something that can be pointed at and it will respond with a representation of the data requested.
# In real terms this could mean a user with a browser requests an HTML page, or that a desktop application
# requests XML data.
#
# RESTful design is based on the assumption that there are four generic verbs that a user of an
# application can request from a resource (the noun).
#
# Resources can be requested using four basic HTTP verbs (GET, POST, PUT, DELETE), the method used
# denotes the type of action that should take place.
#
# === The Different Methods and their Usage
#
# +GET+ Requests for a resource, no saving or editing of a resource should occur in a GET request
# +POST+ Creation of resources
# +PUT+ Editing of attributes on a resource
# +DELETE+ Deletion of a resource
#
# === Examples
#
# # A GET request on the Posts resource is asking for all Posts
# GET /posts
# # A GET request on a single Post resource is asking for that particular Post
# GET /posts/1
# # A POST request on the Posts resource is asking for a Post to be created with the supplied details
# POST /posts # with => { :title => "My Whizzy New Post", :body => "I've got a brand new combine harvester" }
# # A PUT request on a single Post resource is asking for a Post to be updated
# POST /posts # with => { :id => 1, :title => "Changed Whizzy Title" }
# # A DELETE request on a single Post resource is asking for it to be deleted
# DELETE /posts # with => { :id => 1 }
#
# By using the REST convention, users of our application can assume certain things about how the data
# is requested and how it is returned. Rails simplifies the routing part of RESTful design by
# supplying you with methods to create them in your routes.rb file.
#
# Read more about REST at http://en.wikipedia.org/wiki/Representational_State_Transfer
module Resources
class Resource #:nodoc:
attr_reader :collection_methods, :member_methods, :new_methods
attr_reader :path_prefix, :name_prefix
attr_reader :plural, :singular
attr_reader :options
def initialize(entities, options)
@plural = entities
@singular = options[:singular] || plural.to_s.singularize
@options = options
arrange_actions
add_default_actions
set_prefixes
end
def controller
@controller ||= "#{options[:namespace]}#{(options[:controller] || plural).to_s}"
end
def requirements(with_id = false)
@requirements ||= @options[:requirements] || {}
@id_requirement ||= { :id => @requirements.delete(:id) || /[^#{Routing::SEPARATORS.join}]+/ }
with_id ? @requirements.merge(@id_requirement) : @requirements
end
def path
@path ||= "#{path_prefix}/#{plural}"
end
def new_path
@new_path ||= "#{path}/new"
end
def member_path
@member_path ||= "#{path}/:id"
end
def nesting_path_prefix
@nesting_path_prefix ||= "#{path}/:#{singular}_id"
end
def nesting_name_prefix
"#{name_prefix}#{singular}_"
end
protected
def arrange_actions
@collection_methods = arrange_actions_by_methods(options.delete(:collection))
@member_methods = arrange_actions_by_methods(options.delete(:member))
@new_methods = arrange_actions_by_methods(options.delete(:new))
end
def add_default_actions
add_default_action(member_methods, :get, :edit)
add_default_action(new_methods, :get, :new)
end
def set_prefixes
@path_prefix = options.delete(:path_prefix)
@name_prefix = options.delete(:name_prefix)
end
def arrange_actions_by_methods(actions)
(actions || {}).inject({}) do |flipped_hash, (key, value)|
(flipped_hash[value] ||= []) << key
flipped_hash
end
end
def add_default_action(collection, method, action)
(collection[method] ||= []).unshift(action)
end
end
class SingletonResource < Resource #:nodoc:
def initialize(entity, options)
@plural = @singular = entity
@options = options
arrange_actions
add_default_actions
set_prefixes
end
alias_method :member_path, :path
alias_method :nesting_path_prefix, :path
end
# Creates named routes for implementing verb-oriented controllers. This is
# useful for implementing REST API's, where a single resource has different
# behavior based on the HTTP verb (method) used to access it.
#
# Example:
#
# map.resources :messages
#
# class MessagesController < ActionController::Base
# # GET messages_url
# def index
# # return all messages
# end
#
# # GET new_message_url
# def new
# # return an HTML form for describing a new message
# end
#
# # POST messages_url
# def create
# # create a new message
# end
#
# # GET message_url(:id => 1)
# def show
# # find and return a specific message
# end
#
# # GET edit_message_url(:id => 1)
# def edit
# # return an HTML form for editing a specific message
# end
#
# # PUT message_url(:id => 1)
# def update
# # find and update a specific message
# end
#
# # DELETE message_url(:id => 1)
# def destroy
# # delete a specific message
# end
# end
#
# The #resources method sets HTTP method restrictions on the routes it generates. For example, making an
# HTTP POST on <tt>new_message_url</tt> will raise a RoutingError exception. The default route in
# <tt>config/routes.rb</tt> overrides this and allows invalid HTTP methods for resource routes.
#
# Along with the routes themselves, #resources generates named routes for use in
# controllers and views. <tt>map.resources :messages</tt> produces the following named routes and helpers:
#
# Named Route Helpers
# messages messages_url, hash_for_messages_url,
# messages_path, hash_for_messages_path
# message message_url(id), hash_for_message_url(id),
# message_path(id), hash_for_message_path(id)
# new_message new_message_url, hash_for_new_message_url,
# new_message_path, hash_for_new_message_path
# edit_message edit_message_url(id), hash_for_edit_message_url(id),
# edit_message_path(id), hash_for_edit_message_path(id)
#
# You can use these helpers instead of #url_for or methods that take #url_for parameters:
#
# redirect_to :controller => 'messages', :action => 'index'
# # becomes
# redirect_to messages_url
#
# <%= link_to "edit this message", :controller => 'messages', :action => 'edit', :id => @message.id %>
# # becomes
# <%= link_to "edit this message", edit_message_url(@message) # calls @message.id automatically
#
# Since web browsers don't support the PUT and DELETE verbs, you will need to add a parameter '_method' to your
# form tags. The form helpers make this a little easier. For an update form with a <tt>@message</tt> object:
#
# <%= form_tag message_path(@message), :method => :put %>
#
# or
#
# <% form_for :message, @message, :url => message_path(@message), :html => {:method => :put} do |f| %>
#
# The #resources method accepts various options, too, to customize the resulting
# routes:
# * <tt>:controller</tt> -- specify the controller name for the routes.
# * <tt>:singular</tt> -- specify the singular name used in the member routes.
# * <tt>:path_prefix</tt> -- set a prefix to the routes with required route variables.
# Weblog comments usually belong to a post, so you might use resources like:
#
# map.resources :articles
# map.resources :comments, :path_prefix => '/articles/:article_id'
#
# You can nest resources calls to set this automatically:
#
# map.resources :articles do |article|
# article.resources :comments
# end
#
# The comment resources work the same, but must now include a value for :article_id.
#
# comments_url(@article)
# comment_url(@article, @comment)
#
# comments_url(:article_id => @article)
# comment_url(:article_id => @article, :id => @comment)
#
# * <tt>:name_prefix</tt> -- define a prefix for all generated routes, usually ending in an underscore.
# Use this if you have named routes that may clash.
#
# map.resources :tags, :path_prefix => '/books/:book_id', :name_prefix => 'book_'
# map.resources :tags, :path_prefix => '/toys/:toy_id', :name_prefix => 'toy_'
#
# * <tt>:collection</tt> -- add named routes for other actions that operate on the collection.
# Takes a hash of <tt>#{action} => #{method}</tt>, where method is <tt>:get</tt>/<tt>:post</tt>/<tt>:put</tt>/<tt>:delete</tt>
# or <tt>:any</tt> if the method does not matter. These routes map to a URL like /messages/rss, with a route of rss_messages_url.
# * <tt>:member</tt> -- same as :collection, but for actions that operate on a specific member.
# * <tt>:new</tt> -- same as :collection, but for actions that operate on the new resource action.
#
# If <tt>map.resources</tt> is called with multiple resources, they all get the same options applied.
#
# Examples:
#
# map.resources :messages, :path_prefix => "/thread/:thread_id"
# # --> GET /thread/7/messages/1
#
# map.resources :messages, :collection => { :rss => :get }
# # --> GET /messages/rss (maps to the #rss action)
# # also adds a named route called "rss_messages"
#
# map.resources :messages, :member => { :mark => :post }
# # --> POST /messages/1/mark (maps to the #mark action)
# # also adds a named route called "mark_message"
#
# map.resources :messages, :new => { :preview => :post }
# # --> POST /messages/new/preview (maps to the #preview action)
# # also adds a named route called "preview_new_message"
#
# map.resources :messages, :new => { :new => :any, :preview => :post }
# # --> POST /messages/new/preview (maps to the #preview action)
# # also adds a named route called "preview_new_message"
# # --> /messages/new can be invoked via any request method
#
# map.resources :messages, :controller => "categories",
# :path_prefix => "/category/:category_id",
# :name_prefix => "category_"
# # --> GET /categories/7/messages/1
# # has named route "category_message"
def resources(*entities, &block)
options = entities.last.is_a?(Hash) ? entities.pop : { }
entities.each { |entity| map_resource(entity, options.dup, &block) }
end
# Creates named routes for implementing verb-oriented controllers for a singleton resource.
# A singleton resource is global to the current user visiting the application, such as a user's
# /account profile.
#
# See map.resources for general conventions. These are the main differences:
# - a singular name is given to map.resource. The default controller name is taken from the singular name.
# - To specify a custom plural name, use the :plural option. There is no :singular option
# - No default index, new, or create routes are created for the singleton resource controller.
# - When nesting singleton resources, only the singular name is used as the path prefix (example: 'account/messages/1')
#
# Example:
#
# map.resource :account
#
# class AccountController < ActionController::Base
# # POST account_url
# def create
# # create an account
# end
#
# # GET new_account_url
# def new
# # return an HTML form for describing the new account
# end
#
# # GET account_url
# def show
# # find and return the account
# end
#
# # GET edit_account_url
# def edit
# # return an HTML form for editing the account
# end
#
# # PUT account_url
# def update
# # find and update the account
# end
#
# # DELETE account_url
# def destroy
# # delete the account
# end
# end
#
# Along with the routes themselves, #resource generates named routes for use in
# controllers and views. <tt>map.resource :account</tt> produces the following named routes and helpers:
#
# Named Route Helpers
# account account_url, hash_for_account_url,
# account_path, hash_for_account_path
# edit_account edit_account_url, hash_for_edit_account_url,
# edit_account_path, hash_for_edit_account_path
def resource(*entities, &block)
options = entities.last.is_a?(Hash) ? entities.pop : { }
entities.each { |entity| map_singleton_resource(entity, options.dup, &block) }
end
# Enables the use of resources in a module by setting the name_prefix, path_prefix, and namespace for the model.
# Example:
#
# map.namespace(:admin) do |admin|
# admin.resources :products,
# :has_many => [ :tags, :images, :variants ]
# end
#
# This will create admin_products_url pointing to "admin/products", which will look for an Admin::ProductsController.
# It'll also create admin_product_tags_url pointing to "admin/products/#{product_id}/tags", which will look for
# Admin::TagsController.
def namespace(name, options = {}, &block)
with_options({ :path_prefix => name, :name_prefix => "#{name}_", :namespace => "#{name}/" }.merge(options), &block)
end
private
def map_resource(entities, options = {}, &block)
resource = Resource.new(entities, options)
with_options :controller => resource.controller do |map|
map_collection_actions(map, resource)
map_default_collection_actions(map, resource)
map_new_actions(map, resource)
map_member_actions(map, resource)
map_associations(resource, options)
if block_given?
with_options(:path_prefix => resource.nesting_path_prefix, :name_prefix => resource.nesting_name_prefix, &block)
end
end
end
def map_singleton_resource(entities, options = {}, &block)
resource = SingletonResource.new(entities, options)
with_options :controller => resource.controller do |map|
map_collection_actions(map, resource)
map_default_singleton_actions(map, resource)
map_new_actions(map, resource)
map_member_actions(map, resource)
map_associations(resource, options)
if block_given?
with_options(:path_prefix => resource.nesting_path_prefix, :name_prefix => resource.nesting_name_prefix, &block)
end
end
end
def map_associations(resource, options)
Array(options[:has_many]).each do |association|
resources(association, :path_prefix => resource.nesting_path_prefix, :name_prefix => resource.nesting_name_prefix)
end
Array(options[:has_one]).each do |association|
resource(association, :path_prefix => resource.nesting_path_prefix, :name_prefix => resource.nesting_name_prefix)
end
end
def map_collection_actions(map, resource)
resource.collection_methods.each do |method, actions|
actions.each do |action|
action_options = action_options_for(action, resource, method)
map.named_route("#{resource.name_prefix}#{action}_#{resource.plural}", "#{resource.path}/#{action}", action_options)
map.named_route("formatted_#{resource.name_prefix}#{action}_#{resource.plural}", "#{resource.path}/#{action}.:format", action_options)
end
end
end
def map_default_collection_actions(map, resource)
index_action_options = action_options_for("index", resource)
map.named_route("#{resource.name_prefix}#{resource.plural}", resource.path, index_action_options)
map.named_route("formatted_#{resource.name_prefix}#{resource.plural}", "#{resource.path}.:format", index_action_options)
create_action_options = action_options_for("create", resource)
map.connect(resource.path, create_action_options)
map.connect("#{resource.path}.:format", create_action_options)
end
def map_default_singleton_actions(map, resource)
create_action_options = action_options_for("create", resource)
map.connect(resource.path, create_action_options)
map.connect("#{resource.path}.:format", create_action_options)
end
def map_new_actions(map, resource)
resource.new_methods.each do |method, actions|
actions.each do |action|
action_options = action_options_for(action, resource, method)
if action == :new
map.named_route("#{resource.name_prefix}new_#{resource.singular}", resource.new_path, action_options)
map.named_route("formatted_#{resource.name_prefix}new_#{resource.singular}", "#{resource.new_path}.:format", action_options)
else
map.named_route("#{resource.name_prefix}#{action}_new_#{resource.singular}", "#{resource.new_path}/#{action}", action_options)
map.named_route("formatted_#{resource.name_prefix}#{action}_new_#{resource.singular}", "#{resource.new_path}/#{action}.:format", action_options)
end
end
end
end
def map_member_actions(map, resource)
resource.member_methods.each do |method, actions|
actions.each do |action|
action_options = action_options_for(action, resource, method)
map.named_route("#{resource.name_prefix}#{action}_#{resource.singular}", "#{resource.member_path}/#{action}", action_options)
map.named_route("formatted_#{resource.name_prefix}#{action}_#{resource.singular}", "#{resource.member_path}/#{action}.:format",action_options)
end
end
show_action_options = action_options_for("show", resource)
map.named_route("#{resource.name_prefix}#{resource.singular}", resource.member_path, show_action_options)
map.named_route("formatted_#{resource.name_prefix}#{resource.singular}", "#{resource.member_path}.:format", show_action_options)
update_action_options = action_options_for("update", resource)
map.connect(resource.member_path, update_action_options)
map.connect("#{resource.member_path}.:format", update_action_options)
destroy_action_options = action_options_for("destroy", resource)
map.connect(resource.member_path, destroy_action_options)
map.connect("#{resource.member_path}.:format", destroy_action_options)
end
def conditions_for(method)
{ :conditions => method == :any ? {} : { :method => method } }
end
def action_options_for(action, resource, method = nil)
default_options = { :action => action.to_s }
require_id = !resource.kind_of?(SingletonResource)
case default_options[:action]
when "index", "new" : default_options.merge(conditions_for(method || :get)).merge(resource.requirements)
when "create" : default_options.merge(conditions_for(method || :post)).merge(resource.requirements)
when "show", "edit" : default_options.merge(conditions_for(method || :get)).merge(resource.requirements(require_id))
when "update" : default_options.merge(conditions_for(method || :put)).merge(resource.requirements(require_id))
when "destroy" : default_options.merge(conditions_for(method || :delete)).merge(resource.requirements(require_id))
else default_options.merge(conditions_for(method)).merge(resource.requirements)
end
end
end
end
ActionController::Routing::RouteSet::Mapper.send :include, ActionController::Resources