Rails3 Associations and nested attributes - ruby-on-rails-3

Question

I am having trouble when it comes to saving/creating 2 objects at once and associating them to one another. Currently I am doing it in a 'hackish' sort of way by not using nested forms and just passing the parameters for both objects separately (from the view.) Then I connect them in the controller here is my code:
Models
class Post < ActiveRecord::Base
belongs_to :user
has_one :product
accepts_nested_attributes_for :product, :allow_destroy => true
end
class Product < ActiveRecord::Base
belongs_to :user
belongs_to :post
end
View
<%= form_for(#post) do |f| %>
<div id="post_field">
<%= f.text_area :content %>
</div>
<div id="post_link_previewer" class="clearfix">
<%= fields_for :product do |prod| %>
<%= prod.text_field :name %><br />
<%= prod.text_area :description, :rows => 2 %><br />
<%= prod.text_field :image_url %><br />
<%= prod.text_field :original_url %>
<% end %>
</div>
<div id="submit" class="clearfix">
<%= f.submit "Post" %>
</div>
<% end %>
PostsController
def create
#user = current_user
#post = #user.posts.create(params[:post])
#product = Product.create(params[:product])
#post.product_id = #product.id
respond_to do |format|
if #post.save
format.html { redirect_to(root_path, :notice => 'Post was successfully created.') }
format.xml { render :xml => #post, :status => :created, :location => #post }
else
format.html { render :action => "new" }
format.xml { render :xml => #post.errors, :status => :unprocessable_entity }
end
end
end
So when a user makes a post, they can attach a 'product' to that post if they want. The current way I am doing it makes a lot of sense. When I looked at nested form tutorials and see them using build methods I start to get a little confused as to what is going on. Can you help me understand the best way of linking these 2 objects upon create? Is it best to use nested form fields? I feel the current way I am doing it isn't as efficient as it should be.

Answer 1

Yes, you should use nested forms. There is a reason as to why they were built. They ease the process of managing associations and creating nested objects in a single go.
The build method builds an object (it calls the .new() method for the object) and then you can use it.
I advise you to start with a simple example of nested forms and play around with it for an hour or two. This way, you'll have a better understanding of what's happening underneath.
I think, in this case, self-learning by playing would help you a lot, instead of someone just telling you why nested forms are better.
To get you started, refer to nested-attributes-in-rails.