Cancan :创造能力

Question

我有以下代码：

#/app/models/users/user.rb
class Users::User < ActiveRecord::Base
  has_many :phones, class_name: "Users::Phone"
end

#/app/models/users/phone.rb
class Users::Phone < ActiveRecord::Base
  belongs_to :user, class_name: "Users::User"
  attr_accessible :phone
end


#/app/models/ability.rb
class Ability
  include CanCan::Ability

  def initialize(user)

    can :read, :all

    unless user.nil? #logged_in
      if user.is? :admin
        can :manage, :all
      else
        can :create, Users::Phone, user_id: user.id
      end
    end

  end
end

我想检查只为用户创建自己的手机的能力

#/app/views/users/users/show.html.slim
- if can? :create, Users::Phone.new
  a[href="#{new_user_phone_path(@user)}"] Add phone

这不起作用，因为我应该将user_id传递给phone模型(如Users::Phone.new user_id: user.id)，但由于Phone的批量赋值，我不能这样做。

那么，我如何才能检查用户的:create手机功能？

Answer 1

我在我的应用程序中做了类似的事情，让Ability知道底层的参数结构。根据您的需求，您有几个选项。所以在你的控制器中，你大概会有：

def create
  @phone = Users::Phone.new(params[:users_phone])

  # Optional - this just forces the current user to only make phones 
  # for themselves.  If you want to let users make phones for 
  # *certain* others, omit this.
  @phone.user = current_user

  authorize! :create, @phone
  ...
end

然后在你的ability.rb中：

unless user.nil? #logged_in
  if user.is? :admin
    can :manage, :all
  else
    can :create, Users::Phone do |phone|
      # This again forces the user to only make phones for themselves.
      # If you had group-membership logic, it would go here.
      if phone.user == user
        true
      else
        false
      end
    end
  end
end