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Protect attributes from mass-assignment in ActiveRecord models.

This plugin adds attr_accessible and attr_protected in your models.


Add this line to your application's Gemfile:

gem 'protected_attributes'

And then execute:

$ bundle

Or install it yourself as:

$ gem install protected_attributes


Mass assignment security provides an interface for protecting attributes from end-user assignment. This plugin provides two class methods in your Active Record class to control access to your attributes. The attr_protected method takes a list of attributes that will not be accessible for mass-assignment.

For example: ruby attr_protected :admin attr_protected also optionally takes a role option using :as which allows you to define multiple mass-assignment groupings. If no role is defined then attributes will be added to the :default role.

attr_protected :last_login, :as => :admin

A much better way, because it follows the whitelist-principle, is the attr_accessible method. It is the exact opposite of attr_protected, because it takes a list of attributes that will be accessible. All other attributes will be protected. This way you won’t forget to protect attributes when adding new ones in the course of development. Here is an example: ruby attr_accessible :name attr_accessible :name, :is_admin, :as => :admin If you want to set a protected attribute, you will to have to assign it individually: ruby params[:user] # => {:name => "owned", :is_admin => true} @user =[:user]) @user.is_admin # => false, not mass-assigned @user.is_admin = true @user.is_admin # => true When assigning attributes in Active Record using attributes= the :default role will be used. To assign attributes using different roles you should use assign_attributes which accepts an optional :as options parameter. If no :as option is provided then the :default role will be used. You can also bypass mass-assignment security by using the :without_protection option. Here is an example: ```ruby @user =

@user.assign_attributes({ :name => 'Josh', :is_admin => true }) # => Josh @user.is_admin # => false

@user.assign_attributes({ :name => 'Josh', :is_admin => true }, :as => :admin) # => Josh @user.is_admin # => true

@user.assign_attributes({ :name => 'Josh', :is_admin => true }, :without_protection => true) # => Josh @user.is_admin # => true In a similar way, `new`, `create`, `create!`, `update_attributes` and `update_attributes!` methods all respect mass-assignment security and accept either `:as` or `:without_protection` options. For example: ruby @user ={ :name => 'Sebastian', :is_admin => true }, :as => :admin) # => Sebastian @user.is_admin # => true

@user = User.create({ :name => 'Sebastian', :is_admin => true }, :without_protection => true) # => Sebastian @user.is_admin # => true A more paranoid technique to protect your whole project would be to enforce that all models define their accessible attributes. This can be easily achieved with a very simple application config option of: ruby config.active_record.whitelist_attributes = true `` This will create an empty whitelist of attributes available for mass-assignment for all models in your app. As such, your models will need to explicitly whitelist or blacklist accessible parameters by using anattr_accessibleorattr_protecteddeclaration. This technique is best applied at the start of a new project. However, for an existing project with a thorough set of functional tests, it should be straightforward and relatively quick to use this application config option; run your tests, and expose each attribute (viaattr_accessibleorattr_protected`), as dictated by your failing test.

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: ```ruby 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


def account_params role = admin ? :admin : :default sanitize_for_mass_assignment(params[:account], role) end end ```


  1. Fork it
  2. Create your feature branch (git checkout -b my-new-feature)
  3. Commit your changes (git commit -am 'Add some feature')
  4. Push to the branch (git push origin my-new-feature)
  5. Create new Pull Request