Rails4中的多态关联

Question

我正在按照本教程http://blog.endpoint.com/2012/01/ruby-on-rails-rights-attributes.html设置我的rails4应用程序的授权机制。

我已经创建了数据模型，但是不管理（从控制台）（通过all_rights方法）获取用户的权限。

在用户模型中，由于权限是通过RightAssignment而不是直接从User获得的，因此User对象如何调用“ self.rights”？

我的模特：

class User < ActiveRecord::Base
  has_many :right_assignments, as: :subject
  has_and_belongs_to_many :groups
  has_and_belongs_to_many :roles

  def all_rights
    rights = [self.rights +
          self.groups.collect { |g| g.allowed_rights } +
          self.roles.collect { |r| r.rights }]
     rights = rights.flatten.uniq.collect { |r| r.action }
     rights
  end
end

class Group < ActiveRecord::Base
  has_many :right_assignments, as: :subject
  has_and_belongs_to_many :users

  def allowed_rights
    self.assignable_rights ? self.rights : []
  end
end

class Role < ActiveRecord::Base
  has_many :right_assignments, as: :subject
  has_and_belongs_to_many :users
end

class RightAssignment < ActiveRecord::Base
  belongs_to :right
  belongs_to :subject, polymorphic: true
end

class Right < ActiveRecord::Base
  has_many :right_assignments
end

任何想法 ？

Answer 1

您可以使用:through

class User < ActiveRecord::Base
  has_many :right_assignments, as: :subject
  has_many :rights, :through => :right_assignments
  has_and_belongs_to_many :groups
  has_and_belongs_to_many :roles