ruby-on-rails - Rails : most Quiz attributes passing to params, 除了 user_id 之外。为什么？

Question

出于测试/学习目的，我有一个具有以下属性的测验模型(来自 schema.rb 的片段):

create_table "quizzes", force: true do |t|
    t.integer  "user_id"
    t.string   "answer1"
    t.string   "answer2"
    t.string   "answer3"
    t.string   "answer4"
    t.string   "answer5"
    t.string   "answer6"
    t.string   "answer7"
    t.string   "answer8"
    t.datetime "created_at"
    t.datetime "updated_at"
  end

  add_index "quizzes", ["user_id"], name: "index_quizzes_on_user_id"

测验被发送到"new" View ，如下所示:

def new
    @quiz = Quiz.new(user_id: current_user.id)
end

当用户完成测验时，会触发 QuizzesController#create 操作:

def create
    @results = Quiz.create(post_params) #from private method
    render :show
end

(无论这呈现“显示” View 还是默认的“创建” View ，它都有效 - 在我测试和学习时，我现在将这两个 View 作为占位符)

post_params 方法如下所示:

def post_params
    params.require(:quiz).permit(:user_id, :answer1, :answer2, :answer3, :answer4, :answer5, :answer6, :answer7, :answer8) #add other attributes here
end

(我也尝试过 params.require(:quiz).permit! 但我得到了相同的结果)。

问题是，在 View 中，它看起来像这样:

<div class="container">
      <!-- Example row of columns -->
      <div class="row">
        <h1>Results</h1>
        <p><%= @results.inspect %></p>
    </div>
</div>

...@results.inspect 行显示所有 answer1、answer2 等属性，但将 user_id 属性显示为 nil - 尽管在 QuizzessController#new 操作中使用 user_id 设置了测验。我做错了什么，导致 user_id 无法正确传递？

Answer 1

如果您始终要将 user_id 设置为 current_user.id，我建议您在 create 操作中添加该属性.

这样您就不必担心用户输入。否则，用户可能会滥用此更改 ID，从而将测验添加到另一个用户。

首先，从允许的 post_params 中删除 user_id

def post_params
  params.require(:quiz).permit(:answer1, :answer2, :answer3, :answer4, :answer5, :answer6, :answer7, :answer8)
end

然后只需将您的创建操作更新为:

def create
  # as mentioned by tagCindy, this is the way to set up the association
  @quiz = current_user.build_quiz(post_params)

  # you should also re-render the new form if there are any errors
  if @quiz.save
    render :show
  else
    render :new
  end
end