ruby on rails - How to handle nested resources/routes correctly? -

i trying build rails app modded michael hartl's railstutorial. code located on github.

i using following nested resources:

resources :users   resources :scaffolds end 

but getting following error:

actionview::template::error (undefined method `scaffolds_path' #<#    <class:0x007f87848019d0>:0x007f8782651948>): 4:  5: <div class="row"> 6:   <div class="span6 offset3"> 7:     <%= form_for(@scaffold) |f| %> 8:       <%= render 'shared/error_messages', object: f.object %> 9:       <%= f.text_field :name,        placeholder: "scaffold name" %> 10:       <%= f.text_area  :description, placeholder: "description" %>  app/views/scaffolds/new.html.erb:7:in `_app_views_scaffolds_new_html_erb___1119296061714080468_70109999031900' 

i puzzled why looking scaffolds_path , not user_scaffolds_path?

the @scaffold created in app/controller/scaffolds_controller.rb:

def new   @scaffold = current_user.scaffolds.build end 

inspecting @scaffold object created shows:

'#<scaffold id: nil, name: nil, description: nil, tax_id: nil, user_id: 36, created_at: nil, updated_at: nil>' 

dumping methods of @scaffold don't reveal scaffolds_path or user_scaffolds_path methods suggest additional problems?

the users model has_many :scaffolds , scaffold model belongs_to :user.

it has form helper. if you're using nested resources , never want perform controller actions on scaffold objects directly, need following in form view , model. like:

# app/models/user.rb class user < activerecord::base   ...    accepts_nested_attributes_for :scaffolds end 

...and in view...

<%= form_for(@user) |f| %>   ...   <%= fields_for @user.scaffold |scaffold_fields| %> 

...this result in path fields_for giving expected users_scaffolds_path

note specifics of how use fields_for helper changes depending on whether it's has_one or has_many relationship , such. first time through may tear hair out - fair warning.

if, on other hand...

...you want use scaffold objects on own and part of nested route, can declare route twice - once when want use nested resource, , once when want use on own.

# config/routes.rb resources :users   resources :scaffolds end  resources :scaffolds 

with this, when run rake routes you'll see both users_scaffolds_path , scaffolds_path standard actions.