Question

I am using Rails 3.2.2 and am getting the following error. The form below uses a nested model and I am unable to locate the source of the error which I have been trying to locate for days now.

---

ActiveModel::MassAssignmentSecurity::Error in UsersController#create

Can't mass-assign protected attributes: blog

app/controllers/users_controller.rb:17:in `new'
app/controllers/users_controller.rb:17:in `create'

Variables for form

class HomeController < ApplicationController

  def index
    @user = User.new
    @blog = @user.blogs.build
  end
end

User form

<%= form_for @user do |f| %>
 <%= f.text_field :email, :class => 'textbox', :value => 'Email' %><br/><br/>
 <%= f.password_field :password, :class => 'textbox', :value => 'Password' %><br/><br/>
   <%= f.fields_for :blog do |b|%>
     <%= b.text_field :url, :class => 'textbox', :value => 'Blog URL' %></br></br>
   <% end %>

 <%= image_submit_tag("signup.png") %> <br/>
<% end %>

User Controller

class UsersController < ApplicationController

  def create
     @user = User.new(params[:user])   ############## << RUNTIME ERROR #############

     if @user.save 
       flash[:success] = "Welcome!"
       render 'user/success'             
     else
       render 'home/index'
     end
   end

Blog Model

class Blog < ActiveRecord::Base

   belongs_to :user
   attr_accessible :url, :type, :blog_id
   validates :url, :presence => true 

end

User Model

class User < ActiveRecord::Base

  has_many :blogs
  has_many :posts

  accepts_nested_attributes_for :blogs, :allow_destroy => true
  attr_accessible :email, :password, :user_id, :blogs_attributes 
end

Schemas

  create_table "blogs", :force => true do |t|
    t.integer  "user_id"
    t.string   "url"
    t.string   "type"
    t.datetime "created_at", :null => false
    t.datetime "updated_at", :null => false
  end


  create_table "users", :force => true do |t|
    t.string   "email"
    t.datetime "created_at",      :null => false
    t.datetime "updated_at",      :null => false
    t.string   "password_digest"
    t.string   "remember_token"
  end

Answer 1

Try to add an s on blogs like so. Should be blogs.

<%= f.fields_for :blogs do |b|%>
     <%= b.text_field :url, :class => 'textbox', :value => 'Blog URL' %></br></br>
<% end %>