require 'action_controller/mime_type'
require 'action_controller/request'
require 'action_controller/response'
require 'action_controller/routing'
require 'action_controller/code_generation'
require 'action_controller/url_rewriter'
require 'drb'
require 'set'
module ActionController #:nodoc:
class ActionControllerError < StandardError #:nodoc:
end
class SessionRestoreError < ActionControllerError #:nodoc:
end
class MissingTemplate < ActionControllerError #:nodoc:
end
class RoutingError < ActionControllerError #:nodoc:
attr_reader :failures
def initialize(message, failures=[])
super(message)
@failures = failures
end
end
class UnknownController < ActionControllerError #:nodoc:
end
class UnknownAction < ActionControllerError #:nodoc:
end
class MissingFile < 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 only 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\". Finally, note that to cause a before filter to halt execution of the rest of the filter chain, the filter must return false, explicitly, so \"render(...) and return false\"."
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
# Action Controllers are made up of one or more actions that performs its purpose and then either renders a template or
# redirects 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 a mod_rewrite mapping. 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
#
# GuestBookController.template_root = "templates/"
# GuestBookController.process_cgi
#
# All actions assume that you want to render a template matching the name of the action at the end of the performance
# unless you tell it otherwise. The index action complies with this assumption, so after populating the @entries instance
# variable, the GuestBookController will render "templates/guestbook/index.rhtml".
#
# Unlike index, the sign action isn't interested in rendering a template. So after performing its main purpose (creating a
# new entry in the guest book), it sheds the rendering assumption and 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.
#
# Also note that it's the final call to process_cgi that actually initiates the action performance. It will extract
# request and response objects from the CGI
#
# When Action Pack is used inside of Rails, the template_root is automatically configured and you don't need to call process_cgi
# yourself.
#
# == 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 hello_ip
# location = request.env["REMOTE_IP"]
# render :text => "Hello stranger from #{location}"
# end
#
# == Parameters
#
# All request parameters, whether they come from a GET or POST request, or from the URL, are available through the params hash.
# So 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 memory 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 hash accessor:
#
# session[:person] = Person.authenticate(user_name, password)
#
# And retrieved again through the same hash:
#
# Hello #{session[:person]}
#
# Any object can be placed in the session (as long as it can be Marshalled). But remember that 1000 active sessions each storing a
# 50kb object could lead to a 50MB memory overhead. In other words, think carefully about size and caching before resorting to the use
# of the session.
#
# For removing objects from the session, you can either assign a single key to nil, like session[:person] = nil, or you can
# remove the entire session with reset_session.
#
# == 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, so it's normally nothing you'll need to be concerned about.
#
# == 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
#
# Redirecting is what actions that update the model do when they're done. The save_post method shouldn't be responsible for also
# showing the post once it's saved -- that's the job for show_post. So once save_post has completed its business, it'll
# redirect to show_post. All redirects are external, which means that when the user refreshes his browser, it's not going to save
# the post again, but rather just show it one more time.
#
# This sounds fairly simple, but the redirection is complicated by the quest for a phenomenon known as "pretty urls". Instead of accepting
# the dreadful being that is "weblog_controller?action=show&post_id=5", Action Controller goes out of its way to represent the former as
# "/weblog/show/5". And this is even the simple case. As an example of a more advanced pretty url consider
# "/library/books/ISBN/0743536703/show", which can be mapped to books_controller?action=show&type=ISBN&id=0743536703.
#
# Redirects work by rewriting the URL of the current action. So if the show action was called by "/library/books/ISBN/0743536703/show",
# we can redirect to an edit action simply by doing redirect_to(:action => "edit"), which could throw the user to
# "/library/books/ISBN/0743536703/edit". Naturally, you'll need to setup the routes configuration file to point to the proper controller
# and action in the first place, but once you have, it can be rewritten with ease.
#
# Let's consider a bunch of examples on how to go from "/clients/37signals/basecamp/project/dash" to somewhere else:
#
# redirect_to(:action => "edit") =>
# /clients/37signals/basecamp/project/dash
#
# redirect_to(:client_name => "nextangle", :project_name => "rails") =>
# /clients/nextangle/rails/project/dash
#
# Those redirects happen under the configuration of:
#
# map.connect 'clients/:client_name/:project_name/:controller/:action'
#
# == Calling multiple redirects or renders
#
# An action should conclude with a single render or 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
#
# == Environments
#
# Action Controller works out of the box with CGI, FastCGI, and mod_ruby. CGI and mod_ruby controllers are triggered just the same using:
#
# WeblogController.process_cgi
#
# FastCGI controllers are triggered using:
#
# FCGI.each_cgi{ |cgi| WeblogController.process_cgi(cgi) }
class Base
DEFAULT_RENDER_STATUS_CODE = "200 OK"
include Reloadable::Subclasses
# Determines whether the view has access to controller internals @request, @response, @session, and @template.
# By default, it does.
@@view_controller_internals = true
cattr_accessor :view_controller_internals
# Protected instance variable cache
@@protected_variables_cache = nil
cattr_accessor :protected_variables_cache
# 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
# Controls whether the application is thread-safe, so multi-threaded servers like WEBrick know whether to apply a mutex
# around the performance of each action. Action Pack and Active Record are by default thread-safe, but many applications
# may not be. Turned off by default.
@@allow_concurrency = false
cattr_accessor :allow_concurrency
# Modern REST web services often need to submit complex data to the web application.
# The param_parsers hash lets you register handlers wich 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 instanciated
# 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 => :rxml # # # Renders "hello david" # render :inline => "<%= 'hello ' + name %>", :locals => { :name => "david" } # # _Deprecation_ _notice_: This used to have the signature render_template(template, status = 200, type = :rhtml) # # === 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 nothing # # Rendering nothing is often convenient in combination with Ajax calls that perform their effect client-side or # when you just want to communicate a status code. Due to a bug in Safari, nothing actually means a single space. # # # Renders an empty response with status code 200 # render :nothing => true # # # Renders an empty response with status code 401 (access denied) # render :nothing => true, :status => 401 def render(options = nil, deprecated_status = nil, &block) #:doc: raise DoubleRenderError, "Can only render or redirect once per action" if performed? # Backwards compatibility unless options.is_a?(Hash) if options == :update options = {:update => true} else return render_file(options || default_template_name, deprecated_status, true) end end if content_type = options[:content_type] headers["Content-Type"] = content_type end if text = options[:text] render_text(text, options[:status]) else if file = options[:file] render_file(file, options[:status], options[:use_full_path], options[:locals] || {}) elsif template = options[:template] render_file(template, options[:status], true) elsif inline = options[:inline] render_template(inline, options[:status], options[:type], options[:locals] || {}) elsif action_name = options[:action] render_action(action_name, options[:status], options[:layout]) elsif xml = options[:xml] render_xml(xml, options[:status]) elsif partial = options[:partial] partial = default_template_name if partial == true if collection = options[:collection] render_partial_collection(partial, collection, options[:spacer_template], options[:locals], options[:status]) else 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) render_javascript(generator.to_s) elsif options[:nothing] # Safari doesn't pass the headers of the return if the response is zero length render_text(" ", options[:status]) else render_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: result = render(options, &block) erase_render_results forget_variables_added_to_assigns reset_variables_added_to_assigns result end def render_action(action_name, status = nil, with_layout = true) #:nodoc: template = default_template_name(action_name.to_s) if with_layout && !template_exempt_from_layout?(template) render_with_layout(template, status) else render_without_layout(template, status) end end def render_file(template_path, status = nil, use_full_path = false, locals = {}) #:nodoc: add_variables_to_assigns assert_existence_of_template_file(template_path) if use_full_path logger.info("Rendering #{template_path}" + (status ? " (#{status})" : '')) if logger render_text(@template.render_file(template_path, use_full_path, locals), status) end def render_template(template, status = nil, type = :rhtml, local_assigns = {}) #:nodoc: add_variables_to_assigns render_text(@template.render_template(type, template, nil, local_assigns), status) end def render_text(text = nil, status = nil) #:nodoc: @performed_render = true @response.headers['Status'] = (status || DEFAULT_RENDER_STATUS_CODE).to_s @response.body = text end def render_javascript(javascript, status = nil) #:nodoc: @response.headers['Content-Type'] = 'text/javascript; charset=UTF-8' render_text(javascript, status) end def render_xml(xml, status = nil) #:nodoc: @response.headers['Content-Type'] = 'application/xml' render_text(xml, status) end def render_nothing(status = nil) #:nodoc: render_text(' ', status) end def render_partial(partial_path = default_template_name, object = nil, local_assigns = nil, status = nil) #:nodoc: add_variables_to_assigns render_text(@template.render_partial(partial_path, object, local_assigns), status) end def render_partial_collection(partial_name, collection, partial_spacer_template = nil, local_assigns = nil, status = nil) #:nodoc: add_variables_to_assigns render_text(@template.render_partial_collection(partial_name, collection, partial_spacer_template, local_assigns), status) end def render_with_layout(template_name = default_template_name, status = nil, layout = nil) #:nodoc: render_with_a_layout(template_name, status, layout) end def render_without_layout(template_name = default_template_name, status = nil) #:nodoc: render_with_no_layout(template_name, 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) #:doc: 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+. # * 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 "http://www.rubyonrails.org" # redirect_to "/images/screenshot.jpg" # redirect_to :back # # The redirection happens as a "302 Moved" header. # # When using redirect_to :back, if there is no referrer, # RedirectBackError will be raised. You may specify some fallback # behavior for this case by rescueing RedirectBackError. def redirect_to(options = {}, *parameters_for_method_reference) #:doc: case options when %r{^\w+://.*} raise DoubleRenderError if performed? logger.info("Redirected to #{options}") if logger response.redirect(options) response.redirected_to = options @performed_redirect = true when String redirect_to(request.protocol + request.host_with_port + options) when :back request.env["HTTP_REFERER"] ? redirect_to(request.env["HTTP_REFERER"]) : raise(RedirectBackError) else if parameters_for_method_reference.empty? redirect_to(url_for(options)) response.redirected_to = options else redirect_to(url_for(options, *parameters_for_method_reference)) response.redirected_to, response.redirected_to_method_params = options, parameters_for_method_reference end 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 self.view_class @view_class ||= # create a new class based on the default template class and include helper methods returning Class.new(ActionView::Base) do |view_class| view_class.send(:include, master_helper_module) end end def self.view_root @view_root ||= template_root end def initialize_template_class(response) raise "You must assign a template class through ActionController.template_class= before processing a request" unless @@template_class response.template = self.class.view_class.new(self.class.view_root, {}, self) 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 "\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 perform_action if self.class.action_methods.include?(action_name) || self.class.action_methods.include?('method_missing') send(action_name) render unless performed? elsif template_exists? && template_public? 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 action_methods self.class.action_methods end def self.action_methods @action_methods ||= Set.new(public_instance_methods - hidden_actions) end def add_variables_to_assigns unless @variables_added add_instance_variables_to_assigns add_class_variables_to_assigns if view_controller_internals @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 @@protected_variables_cache ||= protected_instance_variables.inject({}) { |h, k| h[k] = true; h } instance_variables.each do |var| next if @@protected_variables_cache.include?(var) @assigns[var[1..-1]] = instance_variable_get(var) end end def add_class_variables_to_assigns %w( template_root logger template_class ignore_missing_templates ).each do |cvar| @assigns[cvar] = self.send(cvar) end end def protected_instance_variables if view_controller_internals [ "@assigns", "@performed_redirect", "@performed_render" ] else [ "@assigns", "@performed_redirect", "@performed_render", "@request", "@response", "@session", "@cookies", "@template", "@request_origin", "@parent_controller" ] 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 unless @session.nil? || Hash === @session 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 =~ /\.rjs$/ || (@template.pick_template_extension(template_name) == :rjs rescue false) end def assert_existence_of_template_file(template_name) unless template_exists?(template_name) || ignore_missing_templates full_template_path = @template.send(:full_template_path, template_name, 'rhtml') template_type = (template_name =~ /layouts/i) ? 'layout' : 'template' raise(MissingTemplate, "Missing #{template_type} #{full_template_path}") end 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