Want to create a new author using "Author" field in the form in books/new, if it doesn't exist yet. The code provided in _form is not working. Routes autor/new, author/create are available.

_form.rb

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

      <ul>
      <% @book.errors.full_messages.each do |msg| %>
        <li><%= msg %></li>
      <% end %>
      </ul>
    </div>
  <% end %>
<ul>
  <li>Title <br>      <%= f.text_field :title   %></li>
  <li>Author<br>      <%= f.text_field :name  %></li>
  <li>Text  <br>      <%= f.text_area  :text    %></li>
</ul>


  <div class="actions">


    <%= f.submit %>
  </div>
<% end %>

author.rb

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

book.rb

class Book < ActiveRecord::Base
  # set_root_path Rails.root.join('config')
  # set_filename 'books'
  validates :title,     :presence => true
  validates :author_id, :presence => true
  validates :text,      :presence => true

  before_create :fix_title
  belongs_to :author

  def fix_title
    self.title = self.title.titleize
  end
end

books_bontroller

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

  def index
    @books = Book.all

    respond_to do |format|
      format.html
      format.yaml { render text:@books.to_yaml }
      format.json { render text:@books.to_json }
    end
  end

  def show
    @book  = Book.find(params[:id])

    respond_to do |format|
      format.html
      format.yaml { render text:@book.to_yaml }
    end
  end

  def new
    @book = Book.new
  end

  def create
    @book = Book.new(book_params)
    if @book.save
      redirect_to book_path(@book)
    else
      render :new
    end
  end

  def edit
    @book  = Book.find(params[:id])
  end

  def update
    @book  = Book.find(params[:id])
  end

  private

  def book_params
    params.require(:book).permit(:title, :text, :author_id)
  end
end

Bookstore::Application.routes.draw do

The priority is based upon order of creation: first created -> highest priority.

See how all your routes lay out with "rake routes".

resources :books
resources :authors, :only => [:index, :create]

You can have the root of your site routed with "root"

root 'books#index'

Example of regular route:

get 'products/:id' => 'catalog#view'

Example of named route that can be invoked with purchase_url(id: product.id)

get 'products/:id/purchase' => 'catalog#purchase', as: :purchase

Example resource route (maps HTTP verbs to controller actions automatically):

resources :products

Example resource route with options:

resources :products do

member do

get 'short'

post 'toggle'

end

collection do

get 'sold'

end

end

Example resource route with sub-resources:

resources :products do

resources :comments, :sales

resource :seller

end

Example resource route with more complex sub-resources:

resources :products do

resources :comments

resources :sales do

get 'recent', on: :collection

end

end

Example resource route with concerns:

concern :toggleable do

post 'toggle'

end

resources :posts, concerns: :toggleable

resources :photos, concerns: :toggleable

Example resource route within a namespace:

namespace :admin do

# Directs /admin/products/* to Admin::ProductsController

# (app/controllers/admin/products_controller.rb)

resources :products

end

end