require 'action_controller/mime_type'
require 'action_controller/request'
require 'action_controller/response'
require 'action_controller/routing'
require 'action_controller/resources'
require 'action_controller/url_rewriter'
require 'action_controller/status_codes'
require 'action_view'
require 'drb'
require 'set'
module ActionController #:nodoc:
class ActionControllerError < StandardError #:nodoc:
end
class SessionRestoreError < ActionControllerError #:nodoc:
end
class RenderError < ActionControllerError #:nodoc:
end
class RoutingError < ActionControllerError #:nodoc:
attr_reader :failures
def initialize(message, failures=[])
super(message)
@failures = failures
end
end
class MethodNotAllowed < ActionControllerError #:nodoc:
attr_reader :allowed_methods
def initialize(*allowed_methods)
super("Only #{allowed_methods.to_sentence} requests are allowed.")
@allowed_methods = allowed_methods
end
def allowed_methods_header
allowed_methods.map { |method_symbol| method_symbol.to_s.upcase } * ', '
end
def handle_response!(response)
response.headers['Allow'] ||= allowed_methods_header
end
end
class NotImplemented < MethodNotAllowed #:nodoc:
end
class UnknownController < ActionControllerError #:nodoc:
end
class UnknownAction < ActionControllerError #:nodoc:
end
class MissingFile < ActionControllerError #:nodoc:
end
class RenderError < ActionControllerError #:nodoc:
end
class SessionOverflowError < ActionControllerError #:nodoc:
DEFAULT_MESSAGE = 'Your session data is larger than the data column in which it is to be stored. You must increase the size of your data column if you intend to store large data.'
def initialize(message = nil)
super(message || DEFAULT_MESSAGE)
end
end
class DoubleRenderError < ActionControllerError #:nodoc:
DEFAULT_MESSAGE = "Render and/or redirect were called multiple times in this action. Please note that you may only call render OR redirect, and at most once per action. Also note that neither redirect nor render terminate execution of the action, so if you want to exit an action after redirecting, you need to do something like \"redirect_to(...) and return\"."
def initialize(message = nil)
super(message || DEFAULT_MESSAGE)
end
end
class RedirectBackError < ActionControllerError #:nodoc:
DEFAULT_MESSAGE = 'No HTTP_REFERER was set in the request to this action, so redirect_to :back could not be called successfully. If this is a test, make sure to specify request.env["HTTP_REFERER"].'
def initialize(message = nil)
super(message || DEFAULT_MESSAGE)
end
end
class UnknownHttpMethod < ActionControllerError #:nodoc:
end
# Action Controllers are the core of a web request in Rails. They are made up of one or more actions that are executed
# on request and then either render a template or redirect to another action. An action is defined as a public method
# on the controller, which will automatically be made accessible to the web-server through Rails Routes.
#
# A sample controller could look like this:
#
# class GuestBookController < ActionController::Base
# def index
# @entries = Entry.find(:all)
# end
#
# def sign
# Entry.create(params[:entry])
# redirect_to :action => "index"
# end
# end
#
# Actions, by default, render a template in the app/views directory corresponding to the name of the controller and action
# after executing code in the action. For example, the +index+ action of the GuestBookController would render the
# template app/views/guestbook/index.erb by default after populating the @entries instance variable.
#
# Unlike index, the sign action will not render a template. After performing its main purpose (creating a
# new entry in the guest book), it initiates a redirect instead. This redirect works by returning an external
# "302 Moved" HTTP response that takes the user to the index action.
#
# The index and sign represent the two basic action archetypes used in Action Controllers. Get-and-show and do-and-redirect.
# Most actions are variations of these themes.
#
# == Requests
#
# Requests are processed by the Action Controller framework by extracting the value of the "action" key in the request parameters.
# This value should hold the name of the action to be performed. Once the action has been identified, the remaining
# request parameters, the session (if one is available), and the full request with all the HTTP headers are made available to
# the action through instance variables. Then the action is performed.
#
# The full request object is available with the request accessor and is primarily used to query for HTTP headers. These queries
# are made by accessing the environment hash, like this:
#
# def server_ip
# location = request.env["SERVER_ADDR"]
# render :text => "This server hosted at #{location}"
# end
#
# == Parameters
#
# All request parameters, whether they come from a GET or POST request, or from the URL, are available through the params method
# which returns a hash. For example, an action that was performed through /weblog/list?category=All&limit=5 will include
# { "category" => "All", "limit" => 5 } in params.
#
# It's also possible to construct multi-dimensional parameter hashes by specifying keys using brackets, such as:
#
#
#
#
# A request stemming from a form holding these inputs will include { "post" => { "name" => "david", "address" => "hyacintvej" } }.
# If the address input had been named "post[address][street]", the params would have included
# { "post" => { "address" => { "street" => "hyacintvej" } } }. There's no limit to the depth of the nesting.
#
# == Sessions
#
# Sessions allows you to store objects in between requests. This is useful for objects that are not yet ready to be persisted,
# such as a Signup object constructed in a multi-paged process, or objects that don't change much and are needed all the time, such
# as a User object for a system that requires login. The session should not be used, however, as a cache for objects where it's likely
# they could be changed unknowingly. It's usually too much work to keep it all synchronized -- something databases already excel at.
#
# You can place objects in the session by using the session method, which accesses a hash:
#
# session[:person] = Person.authenticate(user_name, password)
#
# And retrieved again through the same hash:
#
# Hello #{session[:person]}
#
# For removing objects from the session, you can either assign a single key to +nil+:
#
# # removes :person from session
# session[:person] = nil
#
# or you can remove the entire session with +reset_session+.
#
# Sessions are stored by default in a browser cookie that's cryptographically signed, but unencrypted.
# This prevents the user from tampering with the session but also allows him to see its contents.
#
# Do not put secret information in cookie-based sessions!
#
# Other options for session storage are:
#
# * ActiveRecordStore - Sessions are stored in your database, which works better than PStore with multiple app servers and,
# unlike CookieStore, hides your session contents from the user. To use ActiveRecordStore, set
#
# config.action_controller.session_store = :active_record_store
#
# in your config/environment.rb and run rake db:sessions:create.
#
# * MemCacheStore - Sessions are stored as entries in your memcached cache.
# Set the session store type in config/environment.rb:
#
# config.action_controller.session_store = :mem_cache_store
#
# This assumes that memcached has been installed and configured properly.
# See the MemCacheStore docs for more information.
#
# == Responses
#
# Each action results in a response, which holds the headers and document to be sent to the user's browser. The actual response
# object is generated automatically through the use of renders and redirects and requires no user intervention.
#
# == Renders
#
# Action Controller sends content to the user by using one of five rendering methods. The most versatile and common is the rendering
# of a template. Included in the Action Pack is the Action View, which enables rendering of ERb templates. It's automatically configured.
# The controller passes objects to the view by assigning instance variables:
#
# def show
# @post = Post.find(params[:id])
# end
#
# Which are then automatically available to the view:
#
# Title: <%= @post.title %>
#
# You don't have to rely on the automated rendering. Especially actions that could result in the rendering of different templates will use
# the manual rendering methods:
#
# def search
# @results = Search.find(params[:query])
# case @results
# when 0 then render :action => "no_results"
# when 1 then render :action => "show"
# when 2..10 then render :action => "show_many"
# end
# end
#
# Read more about writing ERb and Builder templates in link:classes/ActionView/Base.html.
#
# == Redirects
#
# Redirects are used to move from one action to another. For example, after a create action, which stores a blog entry to a database,
# we might like to show the user the new entry. Because we're following good DRY principles (Don't Repeat Yourself), we're going to reuse (and redirect to)
# a show action that we'll assume has already been created. The code might look like this:
#
# def create
# @entry = Entry.new(params[:entry])
# if @entry.save
# # The entry was saved correctly, redirect to show
# redirect_to :action => 'show', :id => @entry.id
# else
# # things didn't go so well, do something else
# end
# end
#
# In this case, after saving our new entry to the database, the user is redirected to the show method which is then executed.
#
# == Calling multiple redirects or renders
#
# An action may contain only a single render or a single redirect. Attempting to try to do either again will result in a DoubleRenderError:
#
# def do_something
# redirect_to :action => "elsewhere"
# render :action => "overthere" # raises DoubleRenderError
# end
#
# If you need to redirect on the condition of something, then be sure to add "and return" to halt execution.
#
# def do_something
# redirect_to(:action => "elsewhere") and return if monkeys.nil?
# render :action => "overthere" # won't be called unless monkeys is nil
# end
#
class Base
DEFAULT_RENDER_STATUS_CODE = "200 OK"
include StatusCodes
# Controller specific instance variables which will not be accessible inside views.
@@protected_view_variables = %w(@assigns @performed_redirect @performed_render @variables_added @request_origin @url @parent_controller
@action_name @before_filter_chain_aborted @action_cache_path @_session @_cookies @_headers @_params
@_flash @_response)
# Prepends all the URL-generating helpers from AssetHelper. This makes it possible to easily move javascripts, stylesheets,
# and images to a dedicated asset server away from the main web server. Example:
# ActionController::Base.asset_host = "http://assets.example.com"
@@asset_host = ""
cattr_accessor :asset_host
# All requests are considered local by default, so everyone will be exposed to detailed debugging screens on errors.
# When the application is ready to go public, this should be set to false, and the protected method local_request?
# should instead be implemented in the controller to determine when debugging screens should be shown.
@@consider_all_requests_local = true
cattr_accessor :consider_all_requests_local
# Enable or disable the collection of failure information for RoutingErrors.
# This information can be extremely useful when tweaking custom routes, but is
# pointless once routes have been tested and verified.
@@debug_routes = true
cattr_accessor :debug_routes
# Modern REST web services often need to submit complex data to the web application.
# The @@param_parsers hash lets you register handlers which will process the HTTP body and add parameters to the
# params hash. These handlers are invoked for POST and PUT requests.
#
# By default application/xml is enabled. A XmlSimple class with the same param name as the root will be instantiated
# in the params. This allows XML requests to mask themselves as regular form submissions, so you can have one
# action serve both regular forms and web service requests.
#
# Example of doing your own parser for a custom content type:
#
# ActionController::Base.param_parsers[Mime::Type.lookup('application/atom+xml')] = Proc.new do |data|
# node = REXML::Document.new(post)
# { node.root.name => node.root }
# end
#
# Note: Up until release 1.1 of Rails, Action Controller would default to using XmlSimple configured to discard the
# root node for such requests. The new default is to keep the root, such that "
Good seeing you!
" using Builder # render :inline => "xml.p { 'Good seeing you!' }", :type => :builder # # # Renders "hello david" # render :inline => "<%= 'hello ' + name %>", :locals => { :name => "david" } # # === Rendering inline JavaScriptGenerator page updates # # In addition to rendering JavaScriptGenerator page updates with Ajax in RJS templates (see ActionView::Base for details), # you can also pass the :update parameter to +render+, along with a block, to render page updates inline. # # render :update do |page| # page.replace_html 'user_list', :partial => 'user', :collection => @users # page.visual_effect :highlight, 'user_list' # end # # === Rendering with status and location headers # # All renders take the :status and :location options and turn them into headers. They can even be used together: # # render :xml => post.to_xml, :status => :created, :location => post_url(post) def render(options = nil, extra_options = {}, &block) #:doc: raise DoubleRenderError, "Can only render or redirect once per action" if performed? if options.nil? return render_for_file(default_template_name, nil, true) elsif !extra_options.is_a?(Hash) raise RenderError, "You called render with invalid options : #{options.inspect}, #{extra_options.inspect}" else if options == :update options = extra_options.merge({ :update => true }) elsif !options.is_a?(Hash) raise RenderError, "You called render with invalid options : #{options.inspect}" end end if content_type = options[:content_type] response.content_type = content_type.to_s end if location = options[:location] response.headers["Location"] = url_for(location) end if options.has_key?(:text) render_for_text(options[:text], options[:status]) else if file = options[:file] render_for_file(file, options[:status], nil, options[:locals] || {}) elsif template = options[:template] render_for_file(template, options[:status], true, options[:locals] || {}) elsif inline = options[:inline] add_variables_to_assigns render_for_text(@template.render(options), options[:status]) elsif action_name = options[:action] template = default_template_name(action_name.to_s) if options[:layout] && !template_exempt_from_layout?(template) render_with_a_layout(:file => template, :status => options[:status], :layout => true) else render_with_no_layout(:file => template, :status => options[:status]) end elsif xml = options[:xml] response.content_type ||= Mime::XML render_for_text(xml.respond_to?(:to_xml) ? xml.to_xml : xml, options[:status]) elsif json = options[:json] json = json.to_json unless json.is_a?(String) json = "#{options[:callback]}(#{json})" unless options[:callback].blank? response.content_type ||= Mime::JSON render_for_text(json, options[:status]) elsif partial = options[:partial] partial = default_template_name if partial == true add_variables_to_assigns if collection = options[:collection] render_for_text( @template.send!(:render_partial_collection, partial, collection, options[:spacer_template], options[:locals], options[:as]), options[:status] ) else render_for_text( @template.send!(:render_partial, partial, ActionView::Base::ObjectWrapper.new(options[:object]), options[:locals]), options[:status] ) end elsif options[:update] add_variables_to_assigns @template.send! :evaluate_assigns generator = ActionView::Helpers::PrototypeHelper::JavaScriptGenerator.new(@template, &block) response.content_type = Mime::JS render_for_text(generator.to_s, options[:status]) elsif options[:nothing] # Safari doesn't pass the headers of the return if the response is zero length render_for_text(" ", options[:status]) else render_for_file(default_template_name, options[:status], true) end end end # Renders according to the same rules as render, but returns the result in a string instead # of sending it as the response body to the browser. def render_to_string(options = nil, &block) #:doc: render(options, &block) ensure erase_render_results forget_variables_added_to_assigns reset_variables_added_to_assigns end # Return a response that has no content (merely headers). The options # argument is interpreted to be a hash of header names and values. # This allows you to easily return a response that consists only of # significant headers: # # head :created, :location => person_path(@person) # # It can also be used to return exceptional conditions: # # return head(:method_not_allowed) unless request.post? # return head(:bad_request) unless valid_request? # render def head(*args) if args.length > 2 raise ArgumentError, "too many arguments to head" elsif args.empty? raise ArgumentError, "too few arguments to head" end options = args.extract_options! status = interpret_status(args.shift || options.delete(:status) || :ok) options.each do |key, value| headers[key.to_s.dasherize.split(/-/).map { |v| v.capitalize }.join("-")] = value.to_s end render :nothing => true, :status => status end # Clears the rendered results, allowing for another render to be performed. def erase_render_results #:nodoc: response.body = nil @performed_render = false end # Clears the redirected results from the headers, resets the status to 200 and returns # the URL that was used to redirect or nil if there was no redirected URL # Note that +redirect_to+ will change the body of the response to indicate a redirection. # The response body is not reset here, see +erase_render_results+ def erase_redirect_results #:nodoc: @performed_redirect = false response.redirected_to = nil response.redirected_to_method_params = nil response.headers['Status'] = DEFAULT_RENDER_STATUS_CODE response.headers.delete('Location') end # Erase both render and redirect results def erase_results #:nodoc: erase_render_results erase_redirect_results end def rewrite_options(options) #:nodoc: if defaults = default_url_options(options) defaults.merge(options) else options end 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) end # Redirects the browser to the target specified in +options+. This parameter can take one of three forms: # # * Hash - The URL will be generated by calling url_for with the +options+. # * Record - The URL will be generated by calling url_for with the +options+, which will reference a named URL for that record. # * String starting with protocol:// (like http://) - Is passed straight through as the target for redirection. # * String not containing a protocol - The current protocol and host is prepended to the string. # * :back - Back to the page that issued the request. Useful for forms that are triggered from multiple places. # Short-hand for redirect_to(request.env["HTTP_REFERER"]) # # Examples: # redirect_to :action => "show", :id => 5 # redirect_to post # redirect_to "http://www.rubyonrails.org" # redirect_to "/images/screenshot.jpg" # redirect_to articles_url # redirect_to :back # # The redirection happens as a "302 Moved" header unless otherwise specified. # # Examples: # redirect_to post_url(@post), :status=>:found # redirect_to :action=>'atom', :status=>:moved_permanently # redirect_to post_url(@post), :status=>301 # redirect_to :action=>'atom', :status=>302 # # When using redirect_to :back, if there is no referrer, # RedirectBackError will be raised. You may specify some fallback # behavior for this case by rescuing RedirectBackError. def redirect_to(options = {}, response_status = {}) #:doc: raise ActionControllerError.new("Cannot redirect to nil!") if options.nil? if options.is_a?(Hash) && options[:status] status = options.delete(:status) elsif response_status[:status] status = response_status[:status] else status = 302 end case options when %r{^\w+://.*} raise DoubleRenderError if performed? logger.info("Redirected to #{options}") if logger && logger.info? response.redirect(options, interpret_status(status)) response.redirected_to = options @performed_redirect = true when String redirect_to(request.protocol + request.host_with_port + options, :status=>status) when :back request.env["HTTP_REFERER"] ? redirect_to(request.env["HTTP_REFERER"], :status=>status) : raise(RedirectBackError) when Hash redirect_to(url_for(options), :status=>status) response.redirected_to = options else redirect_to(url_for(options), :status=>status) end end # Sets a HTTP 1.1 Cache-Control header. Defaults to issuing a "private" instruction, so that # intermediate caches shouldn't cache the response. # # Examples: # expires_in 20.minutes # expires_in 3.hours, :private => false # expires in 3.hours, 'max-stale' => 5.hours, :private => nil, :public => true # # This method will overwrite an existing Cache-Control header. # See http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html for more possibilities. def expires_in(seconds, options = {}) #:doc: cache_options = { 'max-age' => seconds, 'private' => true }.symbolize_keys.merge!(options.symbolize_keys) cache_options.delete_if { |k,v| v.nil? or v == false } cache_control = cache_options.map{ |k,v| v == true ? k.to_s : "#{k.to_s}=#{v.to_s}"} response.headers["Cache-Control"] = cache_control.join(', ') end # Sets a HTTP 1.1 Cache-Control header of "no-cache" so no caching should occur by the browser or # intermediate caches (like caching proxy servers). def expires_now #:doc: response.headers["Cache-Control"] = "no-cache" end # Resets the session by clearing out all the objects stored within and initializing a new session object. def reset_session #:doc: request.reset_session @_session = request.session response.session = @_session end private def render_for_file(template_path, status = nil, use_full_path = nil, locals = {}) #:nodoc: add_variables_to_assigns logger.info("Rendering #{template_path}" + (status ? " (#{status})" : '')) if logger render_for_text(@template.render(:file => template_path, :locals => locals), status) end def render_for_text(text = nil, status = nil, append_response = false) #:nodoc: @performed_render = true response.headers['Status'] = interpret_status(status || DEFAULT_RENDER_STATUS_CODE) if append_response response.body ||= '' response.body << text.to_s else response.body = text.is_a?(Proc) ? text : text.to_s end end def initialize_template_class(response) response.template = ActionView::Base.new(self.class.view_paths, {}, self) response.template.extend self.class.master_helper_module response.redirected_to = nil @performed_render = @performed_redirect = false end def assign_shortcuts(request, response) @_request, @_params, @_cookies = request, request.parameters, request.cookies @_response = response @_response.session = request.session @_session = @_response.session @template = @_response.template @assigns = @_response.template.assigns @_headers = @_response.headers end def initialize_current_url @url = UrlRewriter.new(request, params.clone) end def log_processing if logger && logger.info? logger.info "\n\nProcessing #{controller_class_name}\##{action_name} (for #{request_origin}) [#{request.method.to_s.upcase}]" logger.info " Session ID: #{@_session.session_id}" if @_session and @_session.respond_to?(:session_id) logger.info " Parameters: #{respond_to?(:filter_parameters) ? filter_parameters(params).inspect : params.inspect}" end end def default_render #:nodoc: render end def perform_action if self.class.action_methods.include?(action_name) send(action_name) default_render unless performed? elsif respond_to? :method_missing method_missing action_name default_render unless performed? elsif template_exists? && template_public? default_render else raise UnknownAction, "No action responded to #{action_name}", caller end end def performed? @performed_render || @performed_redirect end def assign_names @action_name = (params['action'] || 'index') end def assign_default_content_type_and_charset response.content_type ||= Mime::HTML response.charset ||= self.class.default_charset unless sending_file? end def sending_file? response.headers["Content-Transfer-Encoding"] == "binary" end def action_methods self.class.action_methods end def self.action_methods @action_methods ||= Set.new(public_instance_methods.map(&:to_s)) - hidden_actions end def add_variables_to_assigns unless @variables_added add_instance_variables_to_assigns @variables_added = true end end def forget_variables_added_to_assigns @variables_added = nil end def reset_variables_added_to_assigns @template.instance_variable_set("@assigns_added", nil) end def add_instance_variables_to_assigns (instance_variable_names - @@protected_view_variables).each do |var| @assigns[var[1..-1]] = instance_variable_get(var) end end def request_origin # this *needs* to be cached! # otherwise you'd get different results if calling it more than once @request_origin ||= "#{request.remote_ip} at #{Time.now.to_s(:db)}" end def complete_request_uri "#{request.protocol}#{request.host}#{request.request_uri}" end def close_session @_session.close if @_session && @_session.respond_to?(:close) end def template_exists?(template_name = default_template_name) @template.file_exists?(template_name) end def template_public?(template_name = default_template_name) @template.file_public?(template_name) end def template_exempt_from_layout?(template_name = default_template_name) template_name = @template.send(:template_file_from_name, template_name) if @template @@exempt_from_layout.any? { |ext| template_name.to_s =~ ext } end def default_template_name(action_name = self.action_name) if action_name action_name = action_name.to_s if action_name.include?('/') && template_path_includes_controller?(action_name) action_name = strip_out_controller(action_name) end end "#{self.class.controller_path}/#{action_name}" end def strip_out_controller(path) path.split('/', 2).last end def template_path_includes_controller?(path) self.class.controller_path.split('/')[-1] == path.split('/')[0] end def process_cleanup close_session end end end