Easy Roles

Simple rails gem for basic role authorization with ruby on rails.

Changelog

Please read the CHANGELOG.rdoc file.

Install

gem install gemcutter
gem tumble
gem install easy_roles

or it can be installed as a rails plugin.

script/plugin install git://github.com/platform45/easy_roles.git

Basic Setup

Serialize Method

Add the following to your enviroment.rb in the rails initializer block

config.gem 'easy_roles', :source => 'http://gemcutter.org'

(from version 0.3.0) use the migration generator

script/generate easy_roles user roles

Or add a “roles” column to your users model, and set the default value to “— []”. Please note you can call this column anything you like, I like to use the name “roles”.

t.string :roles, :default => "--- []"

Then you need to add “easy_roles :column_name” to your model.

class User < ActiveRecord::Base
  easy_roles :roles
end

Bitmask Method

WARNING: If you plan on using the column name ‘roles’ for the bitmask method your getter and setter actions will be ‘easy_roles’ and ‘easy_roles=’, instead of ‘roles’ and ‘roles=’. I would suggest using ‘roles_mask’ as your roles column for this method.

Add the following to your enviroment.rb in the rails initializer block

config.gem 'easy_roles', :source => 'http://gemcutter.org'

(from version 0.4.1) use the migration generator to generate the roles column for your users table

E.G. script/generate easy_bitmask_roles user roles_mask

Or add a “roles_mask” column to your users model of type ‘integer’, and set the default value to 0. Please note you can call this column anything you like, I like to use the name “roles_mask”.

t.integer :roles_mask, :default => 0

Add “easy_roles :column_name, :method => :bitmask” to your model.

class User < ActiveRecord::Base
  easy_roles :roles_mask, :method => :bitmask
end

And lastly you need to add a constant variable which stores an array of the different roles for your system. The name of the constant must be the name of your column in full caps.

WARNING: Bitmask storage relies that you DO NOT change the order of your array of roles, if you need to add a new role, just append it to the end of the array.

class User < ActiveRecord::Base
  easy_roles :roles_mask, :method => :bitmask

  # Constant variable storing roles in the system
  ROLES_MASK = %w[admin moderator user]
end

Usage

Easy roles extends your model, and adds a few methods needed for basic role authorization.

adding a role to a user

add_role 'role'

removing a role from a user

remove_role 'role'

check to see if a user has a certain role

has_role? 'role'
# or
is_role? # role being anything you like, for example 'is_admin?' or 'is_awesome?'

For every method above there is a bang method too.

add_role! 'role'
remove_role! 'role'

Examples

@user = User.first

@user.add_role 'admin'

@user.is_admin?
=> true

@user.has_role? 'admin'
=> true

@user.is_awesome?
=> false

@user.add_role 'awesome'

@user.is_awesome?
=> true

@user.remove_role 'admin'

@user.is_admin?
=> false

etc etc

Protecting controllers

There are many ways to implement views for specific roles, so I did not specifically supply one. Here’s an example on what you could do:

class ApplicationController < ActionController::Base

   def admin_required
     unless current_user && current_user.is_admin?
       flash[:error] = "Sorry, you don't have access to that."
       redirect_to root_url and return false
     end
   end

end

Then in your AdminsController or any controller that you only want admins to view:

class AdminsController < ApplicationController
   before_filter :admin_required
end

class MarksController < ApplicationController
   before_filter :admin_required, :only => :create, :update
end

Check out blog.platform45.com/2009/10/05/howto-basic-roles-for-users for implementation, and blog.platform45.com/2009/10/07/easy-roles-gem-released for usage.

Follow me on twitter: twitter.com/ryan_za

Email: ryan at platform45.com

License

Copyright © 2009 Platform45

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the “Software”), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.