Rails4模型忽略'create'动作的parent_id

Question

我有属于类别的子类别.我的应用程序在子类别下保存(构建)我的所有子类别,id = 1,即使我的代码似乎没问题,也不应该这样做:

子类别控制器:

    def create
      @category = Category.find_by(params[:id])
      @subcategory = @category.subcategories.build(subcategory_params)
      if @subcategory.save
        flash[:success] = "added subcategory"
        redirect_to admin_categories_url
      else
        render :new
      end
    end

...

    private

      def subcategory_params
        params.require(:subcategory).permit(:name, :category_id)
      end  

Subcategory.rb

class Subcategory < ActiveRecord::Base
  belongs_to :category
  has_many :products

  validates :name, presence: true
  validates :category_id, presence: true
end

形成:

<h3>Add a subcategory</h3>

<%= form_for [@category, @subcategory] do |f| %>
  <%= f.text_field :name, placeholder: "Name" %>
  <%= f.submit "Add a subcategory" %>
<% end %>

路由器:

resources :categories do
    resources :subcategories
  end

网址:

将新子类别添加到id = 3的类别

http://localhost:3000/categories/3/subcategories/new

日志:

Started POST "/categories/1/subcategories" for 127.0.0.1 at 2014-04-16 16:04:47 +0400
Processing by SubcategoriesController#create as HTML
  Parameters: {"utf8"=>"?", authenticity_token"=>"74U3VyAN6NqEjhkuHGNHnPda/yzpc+dIcn2xBJ6Zi2A=", "subcategory"=>{"name"=>"A name"}, "commit"=>"Add subcategory", "category_id"=>"1"}
  User Load (0.2ms)  SELECT  "users".* FROM "users"  WHERE "users"."id" = $1 LIMIT 1  [["id", 1]]
  Category Load (0.2ms)  SELECT  "categories".* FROM "categories"  WHERE "categories"."id" = $1 LIMIT 1  [["id", 1]]
   (0.1ms)  BEGIN
  SQL (0.2ms)  INSERT INTO "subcategories" ("category_id", "created_at", "name", "updated_at") VALUES ($1, $2, $3, $4) RETURNING "id"  [["category_id", 1], ["created_at", "2014-04-16 12:04:47.151729"], ["name", "A name"], ["updated_at", "2014-04-16 12:04:47.151729"]]
   (0.8ms)  COMMIT

Id是1

这可能是什么问题？

更新

做的时候

@category = Category.find_by(params[:category_id])

出现此错误:

ERROR:  argument of WHERE must be type boolean, not type integer
LINE 1: SELECT  "categories".* FROM "categories"  WHERE (1) LIMIT 1

如果做的话

@category = Category.find(params[:category_id])

问题的主义者

Answer 1

在您的create操作中,您将获取子类别的ID,而不是类别.将其更改为:

def create
  @category = Category.find(params[:category_id])
  ...

同样@category需要在new方法中进行相同的设置更改,以便category_id从视图中的参数中返回3.当然,这种复制也可以使用控制器中的辅助方法进行干扰.

要查看id的差异,您可以使用rake routes,您应该看到类似的内容:

new_category_subcategory   GET   /categories/:category_id/subcategories/new   subcategories#new

这表明它需要参数category_id作为类别的id.