我有一个正常运行的 Rails 3 应用程序，它使用 has_many :through 关联，但我将其重新制作为 Rails 4 应用程序，让我可以在 Rails 4 版本中保存关联模型的 ID。
这些是三个相关模型对于两个版本是相同的。
分类.rb
class Categorization < ActiveRecord::Base
belongs_to :question
belongs_to :category
end
问题.rb
has_many :categorizations
has_many :categories, through: :categorizations
类别.rb
has_many :categorizations
has_many :questions, through: :categorizations
在这两个应用程序中，类别 ID 都像这样传递到创建操作中
"question"=>{"question_content"=>"How do you spell car?", "question_details"=>"blah ", "category_ids"=>["", "2"],
在 Rails 3 应用程序中，当我创建一个新问题时，它会插入到问题表中，然后插入到分类表中
SQL (82.1ms) INSERT INTO "questions" ("accepted_answer_id", "city", "created_at", "details", "province", "province_id", "question", "updated_at", "user_id") VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?) [["accepted_answer_id", nil], ["city", "dd"], ["created_at", Tue, 14 May 2013 17:10:25 UTC +00:00], ["details", "greyound?"], ["province", nil], ["province_id", 2], ["question", "Whos' the biggest dog in the world"], ["updated_at", Tue, 14 May 2013 17:10:25 UTC +00:00], ["user_id", 53]]
SQL (0.4ms) INSERT INTO "categorizations" ("category_id", "created_at", "question_id", "updated_at") VALUES (?, ?, ?, ?) [["category_id", 2], ["created_at", Tue, 14 May 2013 17:10:25 UTC +00:00], ["question_id", 66], ["updated_at", Tue, 14 May 2013 17:10:25 UTC +00:00]]
在 rails 4 应用程序中，在处理 QuestionController#create 中的参数后，我在服务器日志中收到此错误
Unpermitted parameters: category_ids
并且问题只是被插入到问题表中
(0.2ms) BEGIN
SQL (67.6ms) INSERT INTO "questions" ("city", "created_at", "province_id", "question_content", "question_details", "updated_at", "user_id") VALUES ($1, $2, $3, $4, $5, $6, $7) RETURNING "id" [["city", "dd"], ["created_at", Tue, 14 May 2013 17:17:53 UTC +00:00], ["province_id", 3], ["question_content", "How's your car?"], ["question_details", "is it runnign"], ["updated_at", Tue, 14 May 2013 17:17:53 UTC +00:00], ["user_id", 12]]
(31.9ms) COMMIT
虽然我没有将 category_ids 存储在 Questions 模型中，但我将 category_ids 设置为 questions_controller 中的允许参数
def question_params
params.require(:question).permit(:question_details, :question_content, :user_id, :accepted_answer_id, :province_id, :city, :category_ids)
end
谁能解释我应该如何保存 category_ids？请注意，任何一个应用程序的 categories_controller.rb 中都没有创建操作。
这些是两个应用程序中相同的三个表
create_table "questions", force: true do |t|
t.text "question_details"
t.string "question_content"
t.integer "user_id"
t.integer "accepted_answer_id"
t.datetime "created_at"
t.datetime "updated_at"
t.integer "province_id"
t.string "city"
end
create_table "categories", force: true do |t|
t.string "name"
t.datetime "created_at"
t.datetime "updated_at"
end
create_table "categorizations", force: true do |t|
t.integer "category_id"
t.integer "question_id"
t.datetime "created_at"
t.datetime "updated_at"
end
更新
这是 Rails 3 应用程序的创建操作
def create
@question = Question.new(params[:question])
respond_to do |format|
if @question.save
format.html { redirect_to @question, notice: 'Question was successfully created.' }
format.json { render json: @question, status: :created, location: @question }
else
format.html { render action: "new" }
format.json { render json: @question.errors, status: :unprocessable_entity }
end
end
end
这是 Rails 4 应用程序的创建操作
def create
@question = Question.new(question_params)
respond_to do |format|
if @question.save
format.html { redirect_to @question, notice: 'Question was successfully created.' }
format.json { render json: @question, status: :created, location: @question }
else
format.html { render action: "new" }
format.json { render json: @question.errors, status: :unprocessable_entity }
end
end
end
这是 question_params 方法
private
def question_params
params.require(:question).permit(:question_details, :question_content, :user_id, :accepted_answer_id, :province_id, :city, :category_ids)
end