Rails 3 - nested model - jquery file upload

I have a Post model which has_many :photos. While User creating a new
user should be also able to select photos (multiple) for given post.

I am using RAILS 3.2.9, nested_form, carrierwave and
jquery-fileupload-rails gem and ryan bates
railscastshttp://railscasts.com/episodes/381-jquery-file-upload as
a guide.

All seems to be set up correctly, but problem is, when User choose a
(a fileupload() function is triggered), new Post and new Photo record
created. Once I press “create post” another post record is again
created. Any
help/idea how to get rid off with the first Post record once user select
the photo?

Thank you very much.


class Post < ActiveRecord::Base
has_many :photos, as: :attachable, :dependent => :destroy
accepts_nested_attributes_for :photos, :allow_destroy => trueend
class Photo < ActiveRecord::Base
belongs_to :attachable, polymorphic: true
attr_accessible :image, :description, :post_id, :attachable_id,
mount_uploader :image, PhotoUploaderend

Post Controllerdef create

@post = Post.new(params[:post])

_form.html.erb<%= nested_form_for @post, :html => { :multipart => true

} do |f| %>
<%= f.fields_for :photos do |photo| %>
<% if photo.object.new_record? %>
<%= photo.file_field :image, id: “fileupload” %>
<%= photo.hidden_field :id %>
<%= photo.hidden_field :attachable_id %>
<%= photo.hidden_field :attachable_type %>
<% else %>
<%= image_tag(photo.object.image.url(:thumb)) %>
<%= photo.check_box :_destroy %>
<% end %>
<% end %><% end %>