Как вставить MultiSelect в соединительной таблице

Question

Нажатие кнопки отправки возвращает следующее сообщение об ошибке:

NoMethodError in AuthorsController#create 
undefined method `name' for Authorbook:0x007fe6e4284b28 

и параметры запроса:

Parameters: 

{"utf8"=>"✓", 
"authenticity_token"=>"/86GsyhAODP55TYKftsW64Lx1Quy5t/hfthlhG9bcto5+B9CwjejJGcMJyr5+IEpA8xi7FehmSv4cMNxvvadUg==", 
"author"=>{"name"=>"hector"}, 
"books"=>{"id"=>["", 
"2", 
"3"]}, 
"commit"=>"Create Author"} 

Я не знаю, что происходит, по-видимому, контроллер получает имя автора в качестве параметра и не может обрабатывать его.

Модели:

class Author < ActiveRecord::Base 
    validates :name, :presence => true 
    has_many :authorbooks 
    has_many :books, :through => :authorbooks 
end 

class Authorbook < ActiveRecord::Base 
    validates :name, :presence => true 
    belongs_to :book 
    belongs_to :author 
end 

class Book < ActiveRecord::Base 
    validates :name, :presence => true 
    has_many :authorbooks 
    has_many :authors, :through => :authorbooks 
end 

Контроллер:

class AuthorsController < ApplicationController 
    before_action :set_author, only: [:show, :edit, :update, :destroy] 

    # GET /authors 
    # GET /authors.json 
    def index 
    @authors = Author.all 
    end 

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

    # GET /authors/new 
    def new 
    @author = Author.new 

    @all_books = Book.all 

    @author_book = @author.authorbooks.build 
    end 

    # GET /authors/1/edit 
    def edit 
    end 

    # POST /authors 
    # POST /authors.json 
    def create 
    @author = Author.new(author_params) 

    params[:books][:id].each do |book| 
     if !book.empty? 
     @author.authorbooks.build(:book_id => book) 
     end 
    end 

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

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

    # DELETE /authors/1 
    # DELETE /authors/1.json 
    def destroy 
    @author.destroy 
    respond_to do |format| 
     format.html { redirect_to authors_url, notice: 'Author was successfully destroyed.' } 
     format.json { head :no_content } 
    end 
    end 

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

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

и _form:

<%= form_for(@author) do |f| %> 
    <% if @author.errors.any? %> 
    <div id="error_explanation"> 
     <h2><%= pluralize(@author.errors.count, "error") %> prohibited this author from being saved:</h2> 

     <ul> 
     <% @author.errors.full_messages.each do |message| %> 
     <li><%= message %></li> 
     <% end %> 
     </ul> 
    </div> 
    <% end %> 

    <div class="field"> 
    <%= f.label :name %><br> 
    <%= f.text_field :name %> 
    </div> 

    <%= fields_for (@author_book) do |ab| %> 
    <div class="field"> 
     <%= ab.label "All Books" %> <br> 
     <%= collection_select(:books, :id, @all_books, :id, :name, {}, {:multiple => true}) %> 
    </div> 
    <% end %> 

    <div class="actions"> 
    <%= f.submit %> 
    </div> 
<% end %> 

Answer 1

Просто снимите

validates :name, :presence => true #Authorbook  

в «Авторских книгах», потому что ваша модель не имеет этого поля, поэтому в основном вы просто просите Rails проверить поле, которое не существует.