role = {
  'pages' => {
    'index'   => true,
    'show'    => true,
    'new'     => false,
    'edit'    => false,
    'update'  => false,
    'destroy' => false
  },
  'articles' => {
    'index'  => true,
    'show'   => true
  },
  'twitter'  => {
    'button' => true,
    'follow' => false
  }
}

current_user.has_role?(:pages, :show)

current_user.has_role?(:twitter, :button)
current_user.has_role?(:facebook, :like)

  gem 'the_role'

  bundle

def self.up
  create_table :users do |t|
    t.string :login,            :null    => false
    t.string :email,            :default => nil
    t.string :crypted_password, :default => nil
    t.string :salt,             :default => nil

    t.integer :role_id,         :default => nil

    t.timestamps
  end
end

rails g model role --migration=false

rake the_role_engine:install:migrations

rake db:create && rake db:migrate

rake db:roles:test

class ApplicationController < ActionController::Base
  include TheRole::Requires

  protect_from_forgery

  def access_denied
    render :text => 'access_denied: requires an role' and return
  end

  alias_method :login_required,     :YOUR_AUTH_SYSTEM_LOGIN_REQUIRE_METHOD
  alias_method :role_access_denied, :access_denied
end

class PagesController < ApplicationController
  before_filter :login_required, :except => [:index, :show]
  before_filter :role_required,  :except => [:index, :show]

  before_filter :find_page,      :only   => [:edit, :update, :destroy]
  before_filter :owner_required, :only   => [:edit, :update, :destroy]

  private

  def find_page
    @page = Page.find params[:id]
    @ownership_checking_object = @page
  end
end

<% if @user.has_role?(:twitter, :button) %>
  Twitter Button is Here
<% else %>
  Access Denied
<% end %>

class User
  before_create :set_default_role

  private

  def set_default_role
    self.role = Role.where(:name => :user).first
  end
end

admin_role_fragment = {
  :system => {
    :administrator => true
  }
}

moderator_role_fragment = {
  :moderator => {
    :pages   => true,
    :blogs   => false,
    :twitter => true
  }
}

current_user.has_role?(:pages,    :show)  => true | false
current_user.has_role?(:blogs,    :new)   => true | false
current_user.has_role?(:articles, :edit)  => true | false

current_user.moderator?(:pages)           => true | false
current_user.moderator?(:blogs)           => true | false
current_user.moderator?(:articles)        => true | false

current_user.admin?                       => true | false

current_user.owner?(@page)                => true | false
current_user.owner?(@blog)                => true | false
current_user.owner?(@article)             => true | false

# User's role
@role = current_user.role

# Find a Role by name
@role = Role.find_by_name(:user)

@role.has?(:pages, :show)       => true | false
@role.moderator?(:pages)        => true | false
@role.admin?                    => true | false

# Create a section of rules
@role.create_section(:pages)

# Create rule in section (false value by default)
@role.create_rule(:pages, :index)

@role.to_hash => Hash

# JSON string
@role.to_json => String

# JSON string
@role.to_s => String

# check method
@role.has_section?(:pages) => true | false

# check method
@role.has_rule?(:pages, :index) => true | false

# Incoming hash is true-mask-hash
# All rules of Role will be reset to false
# Only rules from true-mask-hash will be set on true
new_role_hash = {
  :pages => {
    :index => true,
    :show => true
  }
}

@role.update_role(new_role_hash)

# set this rule on true
@role.rule_on(:pages, :index)

# set this rule on false
@role.rule_off(:pages, :index)

# delete a section
@role.delete_section(:pages)

# delete rule in section
@role.delete_rule(:pages, :show)