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 => { :post => { :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 # PUT /posts # with => { :id => 1, :post => { :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 INHERITABLE_OPTIONS = :namespace, :shallow class Resource #:nodoc: DEFAULT_ACTIONS = :index, :create, :new, :edit, :show, :update, :destroy attr_reader :collection_methods, :member_methods, :new_methods attr_reader :path_prefix, :name_prefix, :path_segment attr_reader :plural, :singular attr_reader :options def initialize(entities, options) @plural ||= entities @singular ||= options[:singular] || plural.to_s.singularize @path_segment = options.delete(:as) || @plural @options = options arrange_actions add_default_actions set_allowed_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 conditions @conditions ||= @options[:conditions] || {} end def path @path ||= "#{path_prefix}/#{path_segment}" end def new_path new_action = self.options[:path_names][:new] if self.options[:path_names] new_action ||= Base.resources_path_names[:new] @new_path ||= "#{path}/#{new_action}" end def shallow_path_prefix @shallow_path_prefix ||= "#{path_prefix unless @options[:shallow]}" end def member_path @member_path ||= "#{shallow_path_prefix}/#{path_segment}/:id" end def nesting_path_prefix @nesting_path_prefix ||= "#{shallow_path_prefix}/#{path_segment}/:#{singular}_id" end def shallow_name_prefix @shallow_name_prefix ||= "#{name_prefix unless @options[:shallow]}" end def nesting_name_prefix "#{shallow_name_prefix}#{singular}_" end def action_separator @action_separator ||= Base.resource_action_separator end def uncountable? @singular.to_s == @plural.to_s end def has_action?(action) !DEFAULT_ACTIONS.include?(action) || action_allowed?(action) 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_allowed_actions only, except = @options.values_at(:only, :except) @allowed_actions ||= {} if only == :all || except == :none only = nil except = [] elsif only == :none || except == :all only = [] except = nil end if only @allowed_actions[:only] = Array(only).map(&:to_sym) elsif except @allowed_actions[:except] = Array(except).map(&:to_sym) end end def action_allowed?(action) only, except = @allowed_actions.values_at(:only, :except) (!only || only.include?(action)) && (!except || !except.include?(action)) 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) @singular = @plural = entity options[:controller] ||= @singular.to_s.pluralize super end alias_method :shallow_path_prefix, :path_prefix alias_method :shallow_name_prefix, :name_prefix alias_method :member_path, :path alias_method :nesting_path_prefix, :path end # Creates named routes for implementing verb-oriented controllers # for a collection \resource. # # For example: # # map.resources :messages # # will map the following actions in the corresponding controller: # # 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 # # Along with the routes themselves, +resources+ generates named routes for use in # controllers and views. map.resources :messages 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. For example: # # redirect_to :controller => 'messages', :action => 'index' # # and # <%= link_to "edit this message", :controller => 'messages', :action => 'edit', :id => @message.id %> # # now become: # # redirect_to messages_url # # and # <%= 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 @message object: # # <%= form_tag message_path(@message), :method => :put %> # # or # # <% form_for :message, @message, :url => message_path(@message), :html => {:method => :put} do |f| %> # # or # # <% form_for @message do |f| %> # # which takes into account whether @message is a new record or not and generates the # path and method accordingly. # # The +resources+ method accepts the following options to customize the resulting routes: # * :collection - Add named routes for other actions that operate on the collection. # Takes a hash of #{action} => #{method}, where method is :get/:post/:put/:delete, # an array of any of the previous, or :any if the method does not matter. # These routes map to a URL like /messages/rss, with a route of +rss_messages_url+. # * :member - Same as :collection, but for actions that operate on a specific member. # * :new - Same as :collection, but for actions that operate on the new \resource action. # * :controller - Specify the controller name for the routes. # * :singular - Specify the singular name used in the member routes. # * :requirements - Set custom routing parameter requirements; this is a hash of either # regular expressions (which must match for the route to match) or extra parameters. For example: # # map.resource :profile, :path_prefix => ':name', :requirements => { :name => /[a-zA-Z]+/, :extra => 'value' } # # will only match if the first part is alphabetic, and will pass the parameter :extra to the controller. # * :conditions - Specify custom routing recognition conditions. \Resources sets the :method value for the method-specific routes. # * :as - Specify a different \resource name to use in the URL path. For example: # # products_path == '/productos' # map.resources :products, :as => 'productos' do |product| # # product_reviews_path(product) == '/productos/1234/comentarios' # product.resources :product_reviews, :as => 'comentarios' # end # # * :has_one - Specify nested \resources, this is a shorthand for mapping singleton \resources beneath the current. # * :has_many - Same has :has_one, but for plural \resources. # # You may directly specify the routing association with +has_one+ and +has_many+ like: # # map.resources :notes, :has_one => :author, :has_many => [:comments, :attachments] # # This is the same as: # # map.resources :notes do |notes| # notes.resource :author # notes.resources :comments # notes.resources :attachments # end # # * :path_names - Specify different names for the 'new' and 'edit' actions. For example: # # new_products_path == '/productos/nuevo' # map.resources :products, :as => 'productos', :path_names => { :new => 'nuevo', :edit => 'editar' } # # You can also set default action names from an environment, like this: # config.action_controller.resources_path_names = { :new => 'nuevo', :edit => 'editar' } # # * :path_prefix - 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. # # article_comments_url(@article) # article_comment_url(@article, @comment) # # article_comments_url(:article_id => @article) # article_comment_url(:article_id => @article, :id => @comment) # # If you don't want to load all objects from the database you might want to use the article_id directly: # # articles_comments_url(@comment.article_id, @comment) # # * :name_prefix - 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_' # # You may also use :name_prefix to override the generic named routes in a nested \resource: # # map.resources :articles do |article| # article.resources :comments, :name_prefix => nil # end # # This will yield named \resources like so: # # comments_url(@article) # comment_url(@article, @comment) # # * :shallow - If true, paths for nested resources which reference a specific member # (ie. those with an :id parameter) will not use the parent path prefix or name prefix. # # The :shallow option is inherited by any nested resource(s). # # For example, 'users', 'posts' and 'comments' all use shallow paths with the following nested resources: # # map.resources :users, :shallow => true do |user| # user.resources :posts do |post| # post.resources :comments # end # end # # --> GET /users/1/posts (maps to the PostsController#index action as usual) # # also adds the usual named route called "user_posts" # # --> GET /posts/2 (maps to the PostsController#show action as if it were not nested) # # also adds the named route called "post" # # --> GET /posts/2/comments (maps to the CommentsController#index action) # # also adds the named route called "post_comments" # # --> GET /comments/2 (maps to the CommentsController#show action as if it were not nested) # # also adds the named route called "comment" # # You may also use :shallow in combination with the +has_one+ and +has_many+ shorthand notations like: # # map.resources :users, :has_many => { :posts => :comments }, :shallow => true # # * :only and :except - Specify which of the seven default actions should be routed to. # # :only and :except may be set to :all, :none, an action name or a # list of action names. By default, routes are generated for all seven actions. # # For example: # # map.resources :posts, :only => [:index, :show] do |post| # post.resources :comments, :except => [:update, :destroy] # end # # --> GET /posts (maps to the PostsController#index action) # # --> POST /posts (fails) # # --> GET /posts/1 (maps to the PostsController#show action) # # --> DELETE /posts/1 (fails) # # --> POST /posts/1/comments (maps to the CommentsController#create action) # # --> PUT /posts/1/comments/1 (fails) # # If map.resources 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" # # The +resources+ method sets HTTP method restrictions on the routes it generates. For example, making an # HTTP POST on new_message_url will raise a RoutingError exception. The default route in # config/routes.rb overrides this and allows invalid HTTP methods for \resource routes. def resources(*entities, &block) options = entities.extract_options! 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 its current context. For unnested singleton \resources, # the \resource is global to the current user visiting the application, such as a user's # /account profile. For nested singleton \resources, the \resource is global to its parent # \resource, such as a projects \resource that has_one :project_manager. # The project_manager should be mapped as a singleton \resource under projects: # # map.resources :projects do |project| # project.resource :project_manager # end # # See +resources+ for general conventions. These are the main differences: # * A singular name is given to map.resource. The default controller name is still taken from the plural name. # * To specify a custom plural name, use the :plural option. There is no :singular option. # * No default index route is created for the singleton \resource controller. # * When nesting singleton \resources, only the singular name is used as the path prefix (example: 'account/messages/1') # # For example: # # map.resource :account # # maps these actions in the Accounts controller: # # class AccountsController < ActionController::Base # # GET new_account_url # def new # # return an HTML form for describing the new account # end # # # POST account_url # def create # # create an 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. map.resource :account produces # these named routes and helpers: # # Named Route Helpers # ============ ============================================= # account account_url, hash_for_account_url, # account_path, hash_for_account_path # # new_account new_account_url, hash_for_new_account_url, # new_account_path, hash_for_new_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.extract_options! entities.each { |entity| map_singleton_resource(entity, options.dup, &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(options.slice(*INHERITABLE_OPTIONS).merge(: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_new_actions(map, resource) map_member_actions(map, resource) map_default_singleton_actions(map, resource) map_associations(resource, options) if block_given? with_options(options.slice(*INHERITABLE_OPTIONS).merge(:path_prefix => resource.nesting_path_prefix, :name_prefix => resource.nesting_name_prefix), &block) end end end def map_associations(resource, options) map_has_many_associations(resource, options.delete(:has_many), options) if options[:has_many] path_prefix = "#{options.delete(:path_prefix)}#{resource.nesting_path_prefix}" name_prefix = "#{options.delete(:name_prefix)}#{resource.nesting_name_prefix}" Array(options[:has_one]).each do |association| resource(association, options.slice(*INHERITABLE_OPTIONS).merge(:path_prefix => path_prefix, :name_prefix => name_prefix)) end end def map_has_many_associations(resource, associations, options) case associations when Hash associations.each do |association,has_many| map_has_many_associations(resource, association, options.merge(:has_many => has_many)) end when Array associations.each do |association| map_has_many_associations(resource, association, options) end when Symbol, String resources(associations, options.slice(*INHERITABLE_OPTIONS).merge(:path_prefix => resource.nesting_path_prefix, :name_prefix => resource.nesting_name_prefix, :has_many => options[:has_many])) else end end def map_collection_actions(map, resource) resource.collection_methods.each do |method, actions| actions.each do |action| [method].flatten.each do |m| map_resource_routes(map, resource, action, "#{resource.path}#{resource.action_separator}#{action}", "#{action}_#{resource.name_prefix}#{resource.plural}", m) end end end end def map_default_collection_actions(map, resource) index_route_name = "#{resource.name_prefix}#{resource.plural}" if resource.uncountable? index_route_name << "_index" end map_resource_routes(map, resource, :index, resource.path, index_route_name) map_resource_routes(map, resource, :create, resource.path, index_route_name) end def map_default_singleton_actions(map, resource) map_resource_routes(map, resource, :create, resource.path, "#{resource.shallow_name_prefix}#{resource.singular}") end def map_new_actions(map, resource) resource.new_methods.each do |method, actions| actions.each do |action| route_path = resource.new_path route_name = "new_#{resource.name_prefix}#{resource.singular}" unless action == :new route_path = "#{route_path}#{resource.action_separator}#{action}" route_name = "#{action}_#{route_name}" end map_resource_routes(map, resource, action, route_path, route_name, method) end end end def map_member_actions(map, resource) resource.member_methods.each do |method, actions| actions.each do |action| [method].flatten.each do |m| action_path = resource.options[:path_names][action] if resource.options[:path_names].is_a?(Hash) action_path ||= Base.resources_path_names[action] || action map_resource_routes(map, resource, action, "#{resource.member_path}#{resource.action_separator}#{action_path}", "#{action}_#{resource.shallow_name_prefix}#{resource.singular}", m) end end end route_path = "#{resource.shallow_name_prefix}#{resource.singular}" map_resource_routes(map, resource, :show, resource.member_path, route_path) map_resource_routes(map, resource, :update, resource.member_path, route_path) map_resource_routes(map, resource, :destroy, resource.member_path, route_path) end def map_resource_routes(map, resource, action, route_path, route_name = nil, method = nil) if resource.has_action?(action) action_options = action_options_for(action, resource, method) formatted_route_path = "#{route_path}.:format" if route_name && @set.named_routes[route_name.to_sym].nil? map.named_route(route_name, formatted_route_path, action_options) else map.connect(formatted_route_path, action_options) end end end def add_conditions_for(conditions, method) returning({:conditions => conditions.dup}) do |options| options[:conditions][:method] = method unless method == :any end 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(add_conditions_for(resource.conditions, method || :get)).merge(resource.requirements) when "create"; default_options.merge(add_conditions_for(resource.conditions, method || :post)).merge(resource.requirements) when "show", "edit"; default_options.merge(add_conditions_for(resource.conditions, method || :get)).merge(resource.requirements(require_id)) when "update"; default_options.merge(add_conditions_for(resource.conditions, method || :put)).merge(resource.requirements(require_id)) when "destroy"; default_options.merge(add_conditions_for(resource.conditions, method || :delete)).merge(resource.requirements(require_id)) else default_options.merge(add_conditions_for(resource.conditions, method)).merge(resource.requirements) end end end end