ActiveAdmin with CanCan

active_admin_can_can.rb

module ActiveAdminCanCan
  def active_admin_collection
    super.accessible_by current_ability
  end

  def resource
    resource = super
    authorize! permission, resource
    resource
  end

  private

  def permission
    case action_name
    when "show"
      :read
    when "new", "create"
      :create
    when "edit"
      :update
    else
      action_name.to_sym
    end
  end
end

gistfile1.md

...

Useful links

http://blog.genuitytech.com/2012/02/26/activeadmin-and-cancan/
https://gist.github.com/1264060