未经许可的参数：作者

Question

我的要求 基本上我将书籍添加到数据库，并且我想将作者存储在单独的表格中。所以我有一个表格，这个表格叫做作者，这个表格被桌子所引用。

我想创建一个用于添加书籍的Rails表单，并且我希望它只是作者，标题，出版商等的简单表单，并且如果它发现作者已经在authors表中，那么它应该只需引用该记录，并且如果它不在authors表中，那么它应该添加一条新记录并引用它。

同时存储值我得到的日志文件 不允许的参数：作者

Processing by BooksController#create as HTML 
    Parameters: {"utf8"=>"✓", "authenticity_token"=>"8sxeOVMVJucl5nN+kMpSaT1cB1yDPnk5gfKElWPiT5k=", "book"=>{"book_name"=>"life ", "price"=>"20", "author"=>{"author_name"=>"swamy", "title"=>"LIFE", "publisher"=>"cta"}}, "commit"=>"Submit"} 

swamy 
LIFE 
cta 
    Author Load (1.6ms) SELECT "authors".* FROM "authors" WHERE "authors"."author_name" = 'swamy' AND "authors"."title" = 'LIFE' AND "authors"."publisher" = 'cta' LIMIT 1 
    (0.6ms) BEGIN 
    SQL (25.2ms) INSERT INTO "authors" ("author_name", "created_at", "publisher", "title", "updated_at") VALUES ($1, $2, $3, $4, $5) RETURNING "id" [["author_name", "swamy"], ["created_at", "2015-07-01 03:53:22.712401"], ["publisher", "cta"], ["title", "LIFE"], ["updated_at", "2015-07-01 03:53:22.712401"]] 
    (16.8ms) COMMIT 
Unpermitted parameters: author 
    (0.7ms) BEGIN 
    SQL (1.0ms) INSERT INTO "books" ("Author_id", "book_name", "created_at", "price", "updated_at") VALUES ($1, $2, $3, $4, $5) RETURNING "id" [["Author_id", 8], ["book_name", "life "], ["created_at", "2015-07-01 03:53:22.865106"], ["price", 20], ["updated_at", "2015-07-01 03:53:22.865106"]] 
    (22.4ms) COMMIT 

我的代码 books_Controller

class BooksController < ApplicationController 
    def new 

    end 
def create 

    @a=params[:author_name] 
    puts @a 
    b=params[:book][:author][:author_name] 
    puts b 
# @c = @b.authors 
# @d = @c.author_name 
    c=params[:book][:author][:title] 
     d=params[:book][:author][:publisher] 

    puts c 
    puts d 
    @author = Author.find_or_create_by(author_name: b,title: c, publisher: d) 
    @book = Book.new(books_params) 
    @book.Author = @author 
    @book.save 
    redirect_to root_url 

end 
private 

    def books_params 
    params.require(:book).permit(:book_name, :price,:author_attributes => [:author_name, :title, :publisher]) 
end 
end 

模型

class Author < ActiveRecord::Base 

end 

class Book < ActiveRecord::Base 
    belongs_to :Author 
    accepts_nested_attributes_for :Author 
# def author_name=(author_name) 
    # self.author = Author.find_or_create_by_name author_name 
    #end 
end 

视图 books.html。 erb

<%= form_for Book.new do |f| %> 

    <p> 
    <%= f.label :book_name %><br /> 
    <%= f.text_field :book_name %> 
    </p> 
    <p> 
    <%= f.label :price %><br /> 
    <%= f.text_field :price %> 
    </p> 

    <%= f.fields_for :author do |b| %> 
    <p> 
    <%= b.label :author_name%><br /> 
    <%= b.text_field :author_name %> 
    </p> 
<p> 
    <%= b.label :title%><br /> 
    <%= b.text_field :title %> 
    </p> 
<p> 
    <%= b.label :publisher%><br /> 
    <%= b.text_field :publisher%> 
    </p> 

    <% end %> 
    <p><%= f.submit "Submit" %></p> 
<% end %> 
~   

喜先生，我是新来的轨道，我知道这看起来简单，但我无法找到它的解决方案

〜
〜

Answer 1

你的代码是完全错误的。按照我的更改。

#book.rb 
class Book < ActiveRecord::Base 
    belongs_to :author 
    accepts_nested_attributes_for :author 
end 

#books_controller.rb 
def new 
@book = Book.new 
@book.build_author 
end 

def create 
@book = Book.new(books_params) 
if @book.save 
    redirect_to root_url 
end 
end 

最后，在你的形式变化<%= form_for Book.new do |f| %>到<%= form_for @book do |f| %>

Answer 2

那是因为你books_params有author_attributes何时应该基于author在你的参数上。

这应该工作：

def books_params 
    params.require(:book).permit(:book_name, :price, :author => [:author_name, :title, :publisher]) 
end 

Answer 3

变化authore到author_attributes在视图文件，像这样。

<%= f.fields_for :author_attributes do |b| %> 
    <p> 
    <%= b.label :author_name%><br /> 
    <%= b.text_field :author_name %> 
    </p> 

也分别在控制器中进行更改。我认为，这已经足够了。

def create 
    @book = Book.new(books_params) 
    @book.save 
    redirect_to root_url 
end 

Answer 4

我会建议你只debug代码

def books_params 
byebug 
    params.require(:book).permit(:book_name, :price, :author => [:author_name, :title, :publisher]) 
end 

1：检查要求PARAMS

2：查收params.require(:book)

[R equested参数会像

Parameters: {"utf8"=>"✓", "authenticity_token"=>"8sxeOVMVJucl5nN+kMpSaT1cB1yDPnk5gfKElWPiT5k=", "book"=>{"book_name"=>"life ", "price"=>"20", "author_"=>{"author_name"=>"swamy", "title"=>"LIFE", "publisher"=>"cta"}}, "commit"=>"Submit"} 

check with this link NestedAttributes

你的控制器会是这样

class BooksController < ApplicationController 
    def new 
    end 

    def create 
    @author = Author.create(params[:book]) 
    redirect_to root_url 
    end 

    private 

    def books_params 
    params.require(:book).permit(:book_name, :price,:author_attributes => [:author_name, :title, :publisher]) 
    end 
end