Question

I am currently working on a web app for social networking site but it seems as if getting my nested resources to work correctly is impossible. If you can help me out that would be great and I would be very thankful.

Here are my routes. I would like to have the url structure like mysite.com/username/photos /(new, edit, etc). The url structure is like so but I get an error when trying to access the forms or page. Down below I have posted what I have so far.

routes.rb

   resources :users do  
   resources :photos  
   end 

photo.rb

belongs_to :users

user.rb

has_many :photos, :foreign_key => "id", :dependent => :destroy

_form.html.erb
This form has an attachment using paperclip. There is a <% before statement I removed it because it would not show the entire code below on here.

 form_for(@photos,@user) :html => {:multipart => true} do |f| %>

photos_controller.rb

 def new
  @photo = Photo.new(params[:photo])
 end

Answer 1

You need to create a before_filter to get the user, and the form posts to create, not new. Your photo controller should look something like:

before_filter :get_user
...

def new
  @photo = @user.photos.build
end

def create
  @photo = @user.photos.build(params[:photo])
  respond_to do |format|
    if @photo.save
      format.html {redirect_to [@user, @photo], notice: "Photo saved!"}
    else
      format.html {render action: "new"}
    end
  end
end
...
private
def get_user
  @user = User.find(params[:user_id])
end

Here, the before_filter grabs the user. In nested routes, the parent resource ID will be in params[:parent_id] or in this case, params[:user_id]. Then inside the create controller, you want to build a photo from the @user.photos collection. This will automatically create the reference between the photo and the user.

Also, your form_for has the relations backwards. It should be form_for([@user, @photo]) ..., not the other way around.