require 'active_support/core_ext/class/attribute'
require 'active_support/core_ext/string/inflections'
require 'active_support/core_ext/array/wrap'
require 'active_model/mass_assignment_security/permission_set'
require 'active_model/mass_assignment_security/sanitizer'
module ActiveModel
# = Active Model Mass-Assignment Security
module MassAssignmentSecurity
extend ActiveSupport::Concern
included do
class_attribute :_accessible_attributes
class_attribute :_protected_attributes
class_attribute :_active_authorizer
class_attribute :_mass_assignment_sanitizer
self.mass_assignment_sanitizer = :logger
end
# Mass assignment security provides an interface for protecting attributes
# from end-user assignment. For more complex permissions, mass assignment security
# may be handled outside the model by extending a non-ActiveRecord class,
# such as a controller, with this behavior.
#
# For example, a logged in user may need to assign additional attributes depending
# on their role:
#
# class AccountsController < ApplicationController
# include ActiveModel::MassAssignmentSecurity
#
# attr_accessible :first_name, :last_name
# attr_accessible :first_name, :last_name, :plan_id, :as => :admin
#
# def update
# ...
# @account.update_attributes(account_params)
# ...
# end
#
# protected
#
# def account_params
# role = admin ? :admin : :default
# sanitize_for_mass_assignment(params[:account], role)
# end
#
# end
#
# = Configuration options
#
# * <tt>mass_assignment_sanitizer</tt> - Defines sanitize method. Possible values are:
# * <tt>:logger</tt> (default) - writes filtered attributes to logger
# * <tt>:strict</tt> - raise <tt>ActiveModel::MassAssignmentSecurity::Error</tt> on any protected attribute update
#
# You can specify your own sanitizer object eg. MySanitizer.new.
# See <tt>ActiveModel::MassAssignmentSecurity::LoggerSanitizer</tt> for example implementation.
#
#
module ClassMethods
# Attributes named in this macro are protected from mass-assignment
# whenever attributes are sanitized before assignment. A role for the
# attributes is optional, if no role is provided then :default is used.
# A role can be defined by using the :as option.
#
# Mass-assignment to these attributes will simply be ignored, to assign
# to them you can use direct writer methods. This is meant to protect
# sensitive attributes from being overwritten by malicious users
# tampering with URLs or forms. Example:
#
# class Customer
# include ActiveModel::MassAssignmentSecurity
#
# attr_accessor :name, :credit_rating
#
# attr_protected :credit_rating, :last_login
# attr_protected :last_login, :as => :admin
#
# def assign_attributes(values, options = {})
# sanitize_for_mass_assignment(values, options[:as]).each do |k, v|
# send("#{k}=", v)
# end
# end
# end
#
# When using the :default role:
#
# customer = Customer.new
# customer.assign_attributes({ "name" => "David", "credit_rating" => "Excellent", :last_login => 1.day.ago }, :as => :default)
# customer.name # => "David"
# customer.credit_rating # => nil
# customer.last_login # => nil
#
# customer.credit_rating = "Average"
# customer.credit_rating # => "Average"
#
# And using the :admin role:
#
# customer = Customer.new
# customer.assign_attributes({ "name" => "David", "credit_rating" => "Excellent", :last_login => 1.day.ago }, :as => :admin)
# customer.name # => "David"
# customer.credit_rating # => "Excellent"
# customer.last_login # => nil
#
# To start from an all-closed default and enable attributes as needed,
# have a look at +attr_accessible+.
#
# Note that using <tt>Hash#except</tt> or <tt>Hash#slice</tt> in place of
# +attr_protected+ to sanitize attributes provides basically the same
# functionality, but it makes a bit tricky to deal with nested attributes.
def attr_protected(*args)
options = args.extract_options!
role = options[:as] || :default
self._protected_attributes = protected_attributes_configs.dup
Array.wrap(role).each do |name|
self._protected_attributes[name] = self.protected_attributes(name) + args
end
self._active_authorizer = self._protected_attributes
end
# Specifies a white list of model attributes that can be set via
# mass-assignment.
#
# Like +attr_protected+, a role for the attributes is optional,
# if no role is provided then :default is used. A role can be defined by
# using the :as option.
#
# This is the opposite of the +attr_protected+ macro: Mass-assignment
# will only set attributes in this list, to assign to the rest of
# attributes you can use direct writer methods. This is meant to protect
# sensitive attributes from being overwritten by malicious users
# tampering with URLs or forms. If you'd rather start from an all-open
# default and restrict attributes as needed, have a look at
# +attr_protected+.
#
# class Customer
# include ActiveModel::MassAssignmentSecurity
#
# attr_accessor :name, :credit_rating
#
# attr_accessible :name
# attr_accessible :name, :credit_rating, :as => :admin
#
# def assign_attributes(values, options = {})
# sanitize_for_mass_assignment(values, options[:as]).each do |k, v|
# send("#{k}=", v)
# end
# end
# end
#
# When using the :default role:
#
# customer = Customer.new
# customer.assign_attributes({ "name" => "David", "credit_rating" => "Excellent", :last_login => 1.day.ago }, :as => :default)
# customer.name # => "David"
# customer.credit_rating # => nil
#
# customer.credit_rating = "Average"
# customer.credit_rating # => "Average"
#
# And using the :admin role:
#
# customer = Customer.new
# customer.assign_attributes({ "name" => "David", "credit_rating" => "Excellent", :last_login => 1.day.ago }, :as => :admin)
# customer.name # => "David"
# customer.credit_rating # => "Excellent"
#
# Note that using <tt>Hash#except</tt> or <tt>Hash#slice</tt> in place of
# +attr_accessible+ to sanitize attributes provides basically the same
# functionality, but it makes a bit tricky to deal with nested attributes.
def attr_accessible(*args)
options = args.extract_options!
role = options[:as] || :default
self._accessible_attributes = accessible_attributes_configs.dup
Array.wrap(role).each do |name|
self._accessible_attributes[name] = self.accessible_attributes(name) + args
end
self._active_authorizer = self._accessible_attributes
end
def protected_attributes(role = :default)
protected_attributes_configs[role]
end
def accessible_attributes(role = :default)
accessible_attributes_configs[role]
end
def active_authorizers
self._active_authorizer ||= protected_attributes_configs
end
alias active_authorizer active_authorizers
def attributes_protected_by_default
[]
end
def mass_assignment_sanitizer=(value)
self._mass_assignment_sanitizer = if value.is_a?(Symbol)
const_get(:"#{value.to_s.camelize}Sanitizer").new(self)
else
value
end
end
private
def protected_attributes_configs
self._protected_attributes ||= begin
Hash.new { |h,k| h[k] = BlackList.new(attributes_protected_by_default) }
end
end
def accessible_attributes_configs
self._accessible_attributes ||= begin
Hash.new { |h,k| h[k] = WhiteList.new }
end
end
end
protected
def sanitize_for_mass_assignment(attributes, role = nil)
_mass_assignment_sanitizer.sanitize(attributes, mass_assignment_authorizer(role))
end
def mass_assignment_authorizer(role)
self.class.active_authorizer[role || :default]
end
end
end
