Question

我有一个用户模型和一个问题模型。

在用户模型中：

has_many :questions

问题模型：

belongs_to

在我的问题/ show.html.erb

中

<% if @question.user == current_user %>
  <%= link_to 'Edit', edit_question_path(@question) %> | <%= link_to 'Destroy', @question, method: :delete, data: { confirm: 'Are you sure you want to delete this job?' } %>
  <%= link_to 'Back', questions_path %>
<% else %>
  <%= link_to 'Back', questions_path %>
<% end %>

如何只能创建问题的用户编辑并删除它？

Answer 1

查看CanCan的授权宝石Railscasts。{{3}}的Ryan Bates。这对Rails授权需求非常有用。

首先，您将创建一个Ability类，用于定义应用程序中的所有功能。

class Ability
  include CanCan::Ability

  def initialize(user)
    can :manage, Question, user_id: user.id
  end
end

然后，您将能够轻松地将授权集成到您的控制器中。

class QuestionsController < ApplicationController
  def update
    authorize! :manage, @question
    ...
  end
  def destroy
    authorize! :manage, @question
    ...
  end
end

并定制您的观点。

<% if can? :manage, @question %>
  <%= link_to 'Edit', edit_question_path(@question) %> | <%= link_to 'Destroy', @question, method: :delete, data: { confirm: 'Are you sure you want to delete this job?' } %>
<% end %>

Answer 2

您在控制器中只需要：

def destroy
  @question = current_user.questions.find(params[:id])
  @question.destroy

  render ... #anything you want to render
end

之前的代码将确保用户只能删除自己的问题。如果问题的ID不属于用户，则不会删除任何问题，它会抛出ActiveRecord::RecordNotFound - Internal Server error。您可以添加begin - rsecue block以捕获此异常，并根据需要处理它。

def destroy
  begin
   @question = current_user.questions.find(params[:id])
   @question.destroy
   render or redirect_to ....
  rescue Exception ActiveRecord::RecordNotFound
   flash[:notice] = 'not allow to delete this question'
   redirect_to ....
  end
end

其他简单的方法是在控制器中添加一个前置过滤器

before_filter :require_authorization, only: [:delete]
...
def destroy
   @question = current_user.questions.find(params[:id])
   @question.destroy
   render or redirect_to ....
   #With the before filter this code is only going to be executed if the question belongs to the user
end
...
private
def require_authorization
  redirect_to :root unless current_user.questions.find_by_question_id(params[:id])
  #Use the find_by to avoid the ActiveRecord::RecordNotFound and get a nil instead in case the question id doesn't belong to a question of the user
end

Answer 3

您可以尝试将if更改为以下内容：

<% if current_user.questions.include?(@question) %>

您也可以查看:inverse_of

然后，在控制器的“编辑”和“删除”操作中，您可以在显示编辑表单或删除问题之前再次检查正确的用户。

如何只允许帖子的作者编辑或在Ruby on Rails中删除它？

3 个答案: