require "active_support/core_ext/hash/slice" require "active_support/core_ext/hash/except" require "active_support/core_ext/module/anonymous" require "action_dispatch/http/mime_type" module ActionController # Wraps the parameters hash into a nested hash. This will allow clients to # submit requests without having to specify any root elements. # # This functionality is enabled in +config/initializers/wrap_parameters.rb+ # and can be customized. # # You could also turn it on per controller by setting the format array to # a non-empty array: # # class UsersController < ApplicationController # wrap_parameters format: [:json, :xml, :url_encoded_form, :multipart_form] # end # # If you enable +ParamsWrapper+ for +:json+ format, instead of having to # send JSON parameters like this: # # {"user": {"name": "Konata"}} # # You can send parameters like this: # # {"name": "Konata"} # # And it will be wrapped into a nested hash with the key name matching the # controller's name. For example, if you're posting to +UsersController+, # your new +params+ hash will look like this: # # {"name" => "Konata", "user" => {"name" => "Konata"}} # # You can also specify the key in which the parameters should be wrapped to, # and also the list of attributes it should wrap by using either +:include+ or # +:exclude+ options like this: # # class UsersController < ApplicationController # wrap_parameters :person, include: [:username, :password] # end # # On Active Record models with no +:include+ or +:exclude+ option set, # it will only wrap the parameters returned by the class method # attribute_names. # # If you're going to pass the parameters to an +ActiveModel+ object (such as # User.new(params[:user])), you might consider passing the model class to # the method instead. The +ParamsWrapper+ will actually try to determine the # list of attribute names from the model and only wrap those attributes: # # class UsersController < ApplicationController # wrap_parameters Person # end # # You still could pass +:include+ and +:exclude+ to set the list of attributes # you want to wrap. # # By default, if you don't specify the key in which the parameters would be # wrapped to, +ParamsWrapper+ will actually try to determine if there's # a model related to it or not. This controller, for example: # # class Admin::UsersController < ApplicationController # end # # will try to check if Admin::User or +User+ model exists, and use it to # determine the wrapper key respectively. If both models don't exist, # it will then fallback to use +user+ as the key. module ParamsWrapper extend ActiveSupport::Concern EXCLUDE_PARAMETERS = %w(authenticity_token _method utf8) require "mutex_m" class Options < Struct.new(:name, :format, :include, :exclude, :klass, :model) # :nodoc: include Mutex_m def self.from_hash(hash) name = hash[:name] format = Array(hash[:format]) include = hash[:include] && Array(hash[:include]).collect(&:to_s) exclude = hash[:exclude] && Array(hash[:exclude]).collect(&:to_s) new name, format, include, exclude, nil, nil end def initialize(name, format, include, exclude, klass, model) # :nodoc: super @include_set = include @name_set = name end def model super || synchronize { super || self.model = _default_wrap_model } end def include return super if @include_set m = model synchronize do return super if @include_set @include_set = true unless super || exclude if m.respond_to?(:attribute_names) && m.attribute_names.any? if m.respond_to?(:stored_attributes) && !m.stored_attributes.empty? self.include = m.attribute_names + m.stored_attributes.values.flatten.map(&:to_s) else self.include = m.attribute_names end end end end end def name return super if @name_set m = model synchronize do return super if @name_set @name_set = true unless super || klass.anonymous? self.name = m ? m.to_s.demodulize.underscore : klass.controller_name.singularize end end end private # Determine the wrapper model from the controller's name. By convention, # this could be done by trying to find the defined model that has the # same singular name as the controller. For example, +UsersController+ # will try to find if the +User+ model exists. # # This method also does namespace lookup. Foo::Bar::UsersController will # try to find Foo::Bar::User, Foo::User and finally User. def _default_wrap_model return nil if klass.anonymous? model_name = klass.name.sub(/Controller$/, "").classify begin if model_klass = model_name.safe_constantize model_klass else namespaces = model_name.split("::") namespaces.delete_at(-2) break if namespaces.last == model_name model_name = namespaces.join("::") end end until model_klass model_klass end end included do class_attribute :_wrapper_options, default: Options.from_hash(format: []) end module ClassMethods def _set_wrapper_options(options) self._wrapper_options = Options.from_hash(options) end # Sets the name of the wrapper key, or the model which +ParamsWrapper+ # would use to determine the attribute names from. # # ==== Examples # wrap_parameters format: :xml # # enables the parameter wrapper for XML format # # wrap_parameters :person # # wraps parameters into +params[:person]+ hash # # wrap_parameters Person # # wraps parameters by determining the wrapper key from Person class # (+person+, in this case) and the list of attribute names # # wrap_parameters include: [:username, :title] # # wraps only +:username+ and +:title+ attributes from parameters. # # wrap_parameters false # # disables parameters wrapping for this controller altogether. # # ==== Options # * :format - The list of formats in which the parameters wrapper # will be enabled. # * :include - The list of attribute names which parameters wrapper # will wrap into a nested hash. # * :exclude - The list of attribute names which parameters wrapper # will exclude from a nested hash. def wrap_parameters(name_or_model_or_options, options = {}) model = nil case name_or_model_or_options when Hash options = name_or_model_or_options when false options = options.merge(format: []) when Symbol, String options = options.merge(name: name_or_model_or_options) else model = name_or_model_or_options end opts = Options.from_hash _wrapper_options.to_h.slice(:format).merge(options) opts.model = model opts.klass = self self._wrapper_options = opts end # Sets the default wrapper key or model which will be used to determine # wrapper key and attribute names. Called automatically when the # module is inherited. def inherited(klass) if klass._wrapper_options.format.any? params = klass._wrapper_options.dup params.klass = klass klass._wrapper_options = params end super end end # Performs parameters wrapping upon the request. Called automatically # by the metal call stack. def process_action(*args) if _wrapper_enabled? wrapped_hash = _wrap_parameters request.request_parameters wrapped_keys = request.request_parameters.keys wrapped_filtered_hash = _wrap_parameters request.filtered_parameters.slice(*wrapped_keys) # This will make the wrapped hash accessible from controller and view. request.parameters.merge! wrapped_hash request.request_parameters.merge! wrapped_hash # This will display the wrapped hash in the log file. request.filtered_parameters.merge! wrapped_filtered_hash end super end private # Returns the wrapper key which will be used to store wrapped parameters. def _wrapper_key _wrapper_options.name end # Returns the list of enabled formats. def _wrapper_formats _wrapper_options.format end # Returns the list of parameters which will be selected for wrapped. def _wrap_parameters(parameters) { _wrapper_key => _extract_parameters(parameters) } end def _extract_parameters(parameters) if include_only = _wrapper_options.include parameters.slice(*include_only) else exclude = _wrapper_options.exclude || [] parameters.except(*(exclude + EXCLUDE_PARAMETERS)) end end # Checks if we should perform parameters wrapping. def _wrapper_enabled? return false unless request.has_content_type? ref = request.content_mime_type.ref _wrapper_formats.include?(ref) && _wrapper_key && !request.parameters.key?(_wrapper_key) end end end