通过 CanCan 中的多态关联定义能力

Question

我有以下型号：

class Post < ActiveRecord::Base
   has_many :responses, as: :responseable, dependent: :destroy
end

class Call < ActiveRecord::Base
   has_many :responses, as: :responseable, dependent: :destroy
end

class Meeting < ActiveRecord::Base
   has_many :responses, as: :responseable, dependent: :destroy
end

class Response < ActiveRecord::Base
   belongs_to :responseable, polymorphic: true # Tested
end

在 CanCan 中，我试图通过多态关联中的属性来定义特定自定义响应操作的能力。动作如下所示：

class ResponsesController < ApplicationController

  before_filter :authenticate_user!
  load_and_authorize_resource

  respond_to :html, :xml, :js, :json, :pdf


  # GET /responses/polling
  # GET /responses/polling.json
  def polling
    responseable_type = params[:responseable_type]
    klass = [Post, Call, Meeting].detect { |c| responseable_type}
    @responseable = klass.find(params[:responseable_id])
    undivided_millisecond_epoch_time_in_integer = params[:after]
    undivided_millisecond_epoch_time_in_decimal = (undivided_millisecond_epoch_time_in_integer).to_d
    divided_millisecond_epoch_time_in_decimal = (undivided_millisecond_epoch_time_in_decimal / 1000000).to_d
    @responses = @responseable.responses.where("created_at > ?", Time.at(divided_millisecond_epoch_time_in_decimal))
  end
...

此操作通过一个 javascript 函数运行，该函数每 5 秒轮询一次新响应。但是，当它运行时，我在日志中收到以下错误：

A NameError occurred in responses#polling:

  uninitialized constant Responseable
  activesupport (3.2.8) lib/active_support/inflector/methods.rb:230:in `block in constantize'

知道定义这些能力类型的正确方法吗？

Answer 1

你把那个控制器弄得一团糟，试着遵循 REST（或 CRUD）。

无论如何，Cancan 无法检测到您尝试授权的资源。试试这样的：

load_resource :post
load_resource :call
load_resource :meeting
load_and_authorize_resource :response, :through => [:post, :call, :meeting]