Rails 4-複雜的模型驗證（has_many，通過）

Question

我想驗證我的成分模型中的「名稱」屬性。但是，當我在我的Ingredient模型中添加validates：name，：uniqueness => true時，它不驗證名稱（可以插入具有相同名稱的成分）。配料模型與其他模型有着複雜的關係。請參閱下面的代碼。

我的最終目標是允許用戶在成分表中不存在成分時創建成分。如果成分已經存在，則使用成分編號作爲數量。如果任何人有任何想法如何實現這一點，請提供解決方案。提前致謝。

ingredient.rb

class Ingredient < ActiveRecord::Base 
    has_many :quantities 
    has_many :recipes, through: :quantities 

    validates :name, :presence => true, :uniqueness => true 
end 

quantity.rb

class Quantity < ActiveRecord::Base 
    belongs_to :ingredient 
    belongs_to :recipe 

    accepts_nested_attributes_for :ingredient, 
           :reject_if => :all_blank 

    validates :ingredient, :uniqueness => true 
end 

recipe.rb

class Recipe < ActiveRecord::Base 
    has_many :quantities, 
       dependent: :destroy 
    has_many :ingredients, 


       :through => :quantities 

     accepts_nested_attributes_for :quantities, 
             reject_if: :all_blank, 
             allow_destroy: true 

     accepts_nested_attributes_for :ingredients 
end 

用於創建成分視圖部分：

%strong Ingredients: 
    %fieldset#recipe-ingredients 
    %br 
    = f.fields_for :quantities do |builder| 
     = render 'recipe/quantity_fields', f: builder 
    .links 
     = link_to_add_association 'add ingredient', f, :quantities, 'data-association-insertion-node' => '#recipe-ingredients', 'data-assoication-insertion-moethod' => "append", :wrap_object => Proc.new{|quantity| quantity.ingredient.build ; quantity} 
      %br 

配料控制器：

class IngredientController < ApplicationController 
    before_action :set_ingredient, only: [:show, :edit, :update, :destroy] 

    # GET /ingredients 
    # GET /ingredients.json 
    def index 
    @ingredients = Ingredient.all 
    end 

    # GET /ingredients/1 
    # GET /ingredients/1.json 
    def show 
    end 

    # GET /ingredients/new 
    def new 
    @ingredient = Ingredient.new 
    end 

    # GET /ingredients/1/edit 
    def edit 
    end 

    def create 
    @ingredient = Ingredient.new(ingredient_params) 

    respond_to do |format| 
     if @ingredient.save 
     format.html { redirect_to @ingredient, notice: 'Ingredient was successfully created.' } 
     format.json { render :show, status: :created, location: @ingredient } 
     else 
     format.html { render :new } 
     format.json { render json: @ingredient.errors, status: :unprocessable_entity } 
     end 
    end 
    end 

    # PATCH/PUT /ingredients/1 
    # PATCH/PUT /ingredients/1.json 
    def update 
    respond_to do |format| 
     if @ingredient.update(ingredient_params) 
     format.html { redirect_to @ingredient, notice: 'Ingredient was successfully updated.' } 
     format.json { render :show, status: :ok, location: @ingredient } 
     else 
     format.html { render :edit } 
     format.json { render json: @ingredient.errors, status: :unprocessable_entity } 
     end 
    end 
    end 

    # DELETE /ingredients/1 
    # DELETE /ingredients/1.json 
    def destroy 
    @ingredient.destroy 
    respond_to do |format| 
     format.html { redirect_to ingredients_url, notice: 'Ingredient was successfully destroyed.' } 
     format.json { head :no_content } 
    end 
    end 

    private 
    # Use callbacks to share common setup or constraints between actions. 
    def set_ingredient 
     @ingredient = Ingredient.find(params[:id]) 
    end 

    # Never trust parameters from the scary internet, only allow the white list through. 
    def ingredient_params 
     params.require(:ingredient).permit(:name) 
    end 
end 

Answer 1

這似乎是一個已知的問題可能是一個錯誤。選中此項：https://github.com/rails/rails/issues/20676