铁轨 +康康 +多态关联未按预期工作

Question

我正在尝试让 cancan 与多态关联一起工作，我已阅读文档和 wiki，但无法使其工作...

我有以下模型：

class User < ActiveRecord::Base
  has_many :areas, :as => :owner, :dependent => :destroy            
end 

class Account < ActiveRecord::Base  
  has_many :areas, :as => :owner, :dependent => :destroy
end

class Area < ActiveRecord::Base   
  belongs_to :owner, :polymorphic => true
end

在控制器中：

class AreasController < ApplicationController  

  load_resource :user, :instance_name => :owner
  load_resource :account, :instance_name => :owner
  load_and_authorize_resource :area, :through => :owner

  before_filter :authorize_parent

  respond_to :html

  def authorize_parent
    authorize! :manage, @owner
  end    

  def index   
  end          

  def show
    @events = @area.events.page(params[:page]).per(5)
    respond_with @area
  end

  def new 
    respond_with @area
  end               

  def create                                
    @area = @owner.areas.new(params[:area])   
    if @area.save
      flash[:notice] = "Your new area has been created..."
    end  
    respond_with @area
  end

end      

以及以下功能：

  can :manage, Area, :owner => { :memberships => { :user => { :id => user.id } } } # Accounts through Membership     
  can :manage, Area, :owner => { :id => user.id } # User

新的并创建操作对于 user_areas 和 account_areas 都很有效，但是当我尝试转到区域的索引操作时，我收到以下错误：

NameError in AreasController#index

uninitialized constant Owner

有什么想法吗？非常感谢

Answer 1

它认为您的类名为 Owner，也许您可​​以尝试：

load_resource :user, :instance_name => :owner, :class=>'User'
load_resource :account, :instance_name => :owner, :class=>'Account'
load_and_authorize_resource :area, :through => :owner

如果不起作用，请查看此问题是否解决您的问题：https://github.com/ryanb/cancan/issues/73

根据票证，如果您使用的是 1.3 或更高版本，那么您可以执行以下操作：

load_resource :user
load_resource :account
load_and_authorize_resource :area, :through => [:user, :account]

但是在这种情况下你的authorize_parent 方法更改如下：

def authorize_parent
  authorize! :manage, (@user||@account)
end    

有关详细文档，请参阅标题多态关联：https://github.com/ryanb/cancan/wiki/Nested-Resources

让我知道是否适合您。干杯安迪;)