存儲在數據庫，導軌中的權限和角色3.1

Question

在我的應用程序中，我希望以這種方式實現角色和權限，即用戶管理員可以在其瀏覽器中創建新角色。所以我需要權限表和角色表，其中每個角色都是權限的組合。現在我使用了CanCan gem，但這種行爲並不是這個gem的默認行爲，最終我得到了非常複雜的角色結構和權限檢查。任何人都可以告訴我什麼寶石提供這種行爲，或者我應該沒有任何寶石？

Answer 1

見Abilities in Database和Ability for Other Users從康康舞維基：

class Ability 
    include CanCan::Ability 

    def initialize(user) 
    can do |action, subject_class, subject| 
     user.permissions.find_all_by_action(aliases_for_action(action)).any? do |permission| 
     permission.subject_class == subject_class.to_s && 
      (subject.nil? || permission.subject_id.nil? || permission.subject_id == subject.id) 
     end 
    end 
    end 
end 

編輯
一些負載優化：

class Ability 
    include CanCan::Ability 

    def initialize(user, context = nil) 
    if context.nil? 
     can do |action, subject_class, subject| 
     user.permissions.find_all_by_action(aliases_for_action(action)).any? do |permission| 
      permission.subject_class == subject_class.to_s && 
      (subject.nil? || permission.subject_id.nil? || permission.subject_id == subject.id) 
     end 
    elsif context == :post 
     can :manage, Post, :id => y 
    elsif context == :users 
     can :manage, User, :id => x 
    end 
    ... 

並在控制器：

class UsersController 
    protected 
    def current_ability 
    Ability.new(current_user, :users) 

class PostsController 
    protected 
    def current_ability 
    Ability.new(current_user, :posts)