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PORuby on Rails Class Variable not being referenced by controller
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I have a small web app in Ruby on Rails which lists antique documents and the locations that are referenced by the documents. I can update locations that are already attached to documents, but when trying to create a new document, I get the following error <pre><code>undefined method `locations' for nil:NilClass </code></pre> The NilClass occurs in LocationController#new: <pre><code>def new @location = @document.locations.new end </code></pre> This is called from the view as such <pre><code><%= form_for(@location,:url=>new_document_location_path(@document)) do |f| %> <%= render :partial => "document_locations/form", :locals =>{:f=>f} %> <%= f.submit "Save",:class=>"span2 btn" %> <%end%> </code></pre> So for some reason, the @document class isn't being referenced by the controller. I know the class is accessible to the view and in scope as I am able to view document attributes within the form (eg <%= @document.id %> So, why is the Controller not able to reference the @document variable? I'm assuming this is down to how I am passing the class variable. Eitherway, I'd be very grateful for some pointers. This is how the models are defined <pre><code>class Document < ActiveRecord::Base has_many :locations, :dependent => :destroy end class Location < ActiveRecord::Base belongs_to :document end </code></pre> Here's my routes <pre><code>Pastpaper::Application.routes.draw do # added in to test match '/documents/:id/locations/create' => 'locations#create' resources :documents do collection do match 'permanent_delete/:id' => 'documents#permanently_delete',:as => :permanent_delete end match '/authorinfo' => 'documents#authorinfo',:as => :authorinfo match '/publicationinfo' => 'documents#publicationinfo',:as => :publicationinfo match '/images' => 'documents#itemimages' ,:as => :itemimages match '/locations' => 'documents#locations',:as => :locations match '/itempeople' => 'documents#itempeople' ,:as => :itempeople match '/people_facts_locations' => 'documents#people_facts_locations',:as => :people_facts_loc resources :locations, :controller=>"locations" resources :people ,:controller => "document_people" resources :document_facts resource :facts resources :document_photos end resources :home do collection do get 'document_search','simple_location_search','date_search','simple_people_search','simple_organisation_search','document_filter' get 'search_results' post 'search_results' end end match 'documents/publicationinfo/:id' => 'documents#publicationinfo',:as => :publicationinfo match 'documents/update/publishinginfo/:id' => 'documents#publishinginfo',:as => :publishinginfo match 'documents/document_image_remove/:id' => 'documents#remove_image',:as=>"remove_image" match 'documents/make_primary_image/:id' => 'documents#make_primary_image',:as => :make_primary_image match 'person_detail/:id' => 'documents#person_detail',:as=>'person_detail' match 'about', :to=> 'pages#about' match 'contact', :to => 'pages#contact' match 'privacy', :to => 'pages#privacy' match 'terms', :to => 'pages#terms' match 'help', :to => 'pages#help' namespace :admin do resources :document_types resources :statuses resources :attribute_types resources :event_types resources :users resources :orders resources :documents match 'restore_document/:id' => 'Documents#restore_document', :as => 'restore_document' match 'report' => 'report#index' ,:as=>:report match 'report/surname_report' => 'report#surname_report',:as=>:surname_report match 'report/location_report' => 'report#location_report',:as=>:location_report end root :to => 'home#index' end </code></pre> And here's the relevant Controllers: DocumentController <pre><code>class DocumentsController < ApplicationController before_filter :prepare_document ,:only => [:locations] def locations @locations = @document.locations.order("id asc") @location = @document.locations.new end private def prepare_document if params[:id] @document = Document.find(params[:id], :include => [:document_attributes]) elsif params[:document_id] @document = Document.find(params[:document_id], :include => [:document_attributes]) end end end </code></pre> LocationsController <pre><code>class LocationsController < ApplicationController before_filter :prepare_document def new @location = @document.locations.new end def create @location = @document.locations.build if @location.save redirect_to document_locations_url(@document) else render "new" end end def update @location = @document.locations.find(params[:id]) if @location.update_attributes(params[:location]) redirect_to document_locations_url(@document) else render "edit" end end def prepare_document if params[:document_id] if current_user.is_admin? @document = Document.find(params[:document_id], :include => [:document_attributes]) else @document = current_user.documents.find(params[:document_id], :include => [:document_attributes]) end end end end </code></pre> This is how my routes rake out <pre><code> logout GET /logout(.:format) {:action=>"destroy", :controller=>"sessions"} login POST /login(.:format) {:action=>"create", :controller=>"sessions"} forgot_password /forgot_password(.:format) {:action=>"new", :controller=>"password_resets"} user_home GET /profile(.:format) {:action=>"index", :controller=>"users"} deactivateaccount /account/deactivate(.:format) {:controller=>"users", :action=>"accountdeactivate"} changepassword /account/changepassword(.:format) {:controller=>"users", :action=>"changepassword"} register /user/registration(.:format) {:controller=>"users", :action=>"new"} users GET /users(.:format) {:action=>"index", :controller=>"users"} POST /users(.:format) {:action=>"create", :controller=>"users"} new_user GET /users/new(.:format) {:action=>"new", :controller=>"users"} edit_user GET /users/:id/edit(.:format) {:action=>"edit", :controller=>"users"} user GET /users/:id(.:format) {:action=>"show", :controller=>"users"} PUT /users/:id(.:format) {:action=>"update", :controller=>"users"} DELETE /users/:id(.:format) {:action=>"destroy", :controller=>"users"} password_resets GET /password_resets(.:format) {:action=>"index", :controller=>"password_resets"} POST /password_resets(.:format) {:action=>"create", :controller=>"password_resets"} new_password_reset GET /password_resets/new(.:format) {:action=>"new", :controller=>"password_resets"} edit_password_reset GET /password_resets/:id/edit(.:format) {:action=>"edit", :controller=>"password_resets"} password_reset GET /password_resets/:id(.:format) {:action=>"show", :controller=>"password_resets"} PUT /password_resets/:id(.:format) {:action=>"update", :controller=>"password_resets"} DELETE /password_resets/:id(.:format) {:action=>"destroy", :controller=>"password_resets"} password_reset_path /password_resets/:id/edit(.:format) {:controller=>"password_resets", :action=>"edit"} /documents/:id/locations/create(.:format) {:controller=>"locations", :action=>"create"} permanent_delete_documents /documents/permanent_delete/:id(.:format) {:controller=>"documents", :action=>"permanently_delete"} document_authorinfo /documents/:document_id/authorinfo(.:format) {:controller=>"documents", :action=>"authorinfo"} document_publicationinfo /documents/:document_id/publicationinfo(.:format) {:controller=>"documents", :action=>"publicationinfo"} document_itemimages /documents/:document_id/images(.:format) {:controller=>"documents", :action=>"itemimages"} document_locations /documents/:document_id/locations(.:format) {:controller=>"documents", :action=>"locations"} document_itempeople /documents/:document_id/itempeople(.:format) {:controller=>"documents", :action=>"itempeople"} document_people_facts_loc /documents/:document_id/people_facts_locations(.:format) {:controller=>"documents", :action=>"people_facts_locations"} GET /documents/:document_id/locations(.:format) {:action=>"index", :controller=>"locations"} POST /documents/:document_id/locations(.:format) {:action=>"create", :controller=>"locations"} new_document_location GET /documents/:document_id/locations/new(.:format) {:action=>"new", :controller=>"locations"} edit_document_location GET /documents/:document_id/locations/:id/edit(.:format) {:action=>"edit", :controller=>"locations"} document_location GET /documents/:document_id/locations/:id(.:format) {:action=>"show", :controller=>"locations"} PUT /documents/:document_id/locations/:id(.:format) {:action=>"update", :controller=>"locations"} DELETE /documents/:document_id/locations/:id(.:format) {:action=>"destroy", :controller=>"locations"} document_people GET /documents/:document_id/people(.:format) {:action=>"index", :controller=>"document_people"} POST /documents/:document_id/people(.:format) {:action=>"create", :controller=>"document_people"} new_document_person GET /documents/:document_id/people/new(.:format) {:action=>"new", :controller=>"document_people"} edit_document_person GET /documents/:document_id/people/:id/edit(.:format) {:action=>"edit", :controller=>"document_people"} document_person GET /documents/:document_id/people/:id(.:format) {:action=>"show", :controller=>"document_people"} PUT /documents/:document_id/people/:id(.:format) {:action=>"update", :controller=>"document_people"} DELETE /documents/:document_id/people/:id(.:format) {:action=>"destroy", :controller=>"document_people"} document_document_facts GET /documents/:document_id/document_facts(.:format) {:action=>"index", :controller=>"document_facts"} POST /documents/:document_id/document_facts(.:format) {:action=>"create", :controller=>"document_facts"} new_document_document_fact GET /documents/:document_id/document_facts/new(.:format) {:action=>"new", :controller=>"document_facts"} edit_document_document_fact GET /documents/:document_id/document_facts/:id/edit(.:format) {:action=>"edit", :controller=>"document_facts"} document_document_fact GET /documents/:document_id/document_facts/:id(.:format) {:action=>"show", :controller=>"document_facts"} PUT /documents/:document_id/document_facts/:id(.:format) {:action=>"update", :controller=>"document_facts"} DELETE /documents/:document_id/document_facts/:id(.:format) {:action=>"destroy", :controller=>"document_facts"} document_facts POST /documents/:document_id/facts(.:format) {:action=>"create", :controller=>"facts"} new_document_facts GET /documents/:document_id/facts/new(.:format) {:action=>"new", :controller=>"facts"} edit_document_facts GET /documents/:document_id/facts/edit(.:format) {:action=>"edit", :controller=>"facts"} GET /documents/:document_id/facts(.:format) {:action=>"show", :controller=>"facts"} PUT /documents/:document_id/facts(.:format) {:action=>"update", :controller=>"facts"} DELETE /documents/:document_id/facts(.:format) {:action=>"destroy", :controller=>"facts"} document_document_photos GET /documents/:document_id/document_photos(.:format) {:action=>"index", :controller=>"document_photos"} POST /documents/:document_id/document_photos(.:format) {:action=>"create", :controller=>"document_photos"} new_document_document_photo GET /documents/:document_id/document_photos/new(.:format) {:action=>"new", :controller=>"document_photos"} edit_document_document_photo GET /documents/:document_id/document_photos/:id/edit(.:format) {:action=>"edit", :controller=>"document_photos"} document_document_photo GET /documents/:document_id/document_photos/:id(.:format) {:action=>"show", :controller=>"document_photos"} PUT /documents/:document_id/document_photos/:id(.:format) {:action=>"update", :controller=>"document_photos"} DELETE /documents/:document_id/document_photos/:id(.:format) {:action=>"destroy", :controller=>"document_photos"} documents GET /documents(.:format) {:action=>"index", :controller=>"documents"} POST /documents(.:format) {:action=>"create", :controller=>"documents"} new_document GET /documents/new(.:format) {:action=>"new", :controller=>"documents"} edit_document GET /documents/:id/edit(.:format) {:action=>"edit", :controller=>"documents"} document GET /documents/:id(.:format) {:action=>"show", :controller=>"documents"} PUT /documents/:id(.:format) {:action=>"update", :controller=>"documents"} DELETE /documents/:id(.:format) {:action=>"destroy", :controller=>"documents"} paypal_cancel /payments/cancel(.:format) {:controller=>"payments", :action=>"paypal_cancel"} paypal_return /payments/success(.:format) {:controller=>"payments", :action=>"paypal_return"} paypal_ipn /payments/ipn(.:format) {:controller=>"payments", :action=>"create"} document_search_home_index GET /home/document_search(.:format) {:action=>"document_search", :controller=>"home"} simple_location_search_home_index GET /home/simple_location_search(.:format) {:action=>"simple_location_search", :controller=>"home"} date_search_home_index GET /home/date_search(.:format) {:action=>"date_search", :controller=>"home"} simple_people_search_home_index GET /home/simple_people_search(.:format) {:action=>"simple_people_search", :controller=>"home"} simple_organisation_search_home_index GET /home/simple_organisation_search(.:format) {:action=>"simple_organisation_search", :controller=>"home"} document_filter_home_index GET /home/document_filter(.:format) {:action=>"document_filter", :controller=>"home"} search_results_home_index GET /home/search_results(.:format) {:action=>"search_results", :controller=>"home"} POST /home/search_results(.:format) {:action=>"search_results", :controller=>"home"} home_index GET /home(.:format) {:action=>"index", :controller=>"home"} POST /home(.:format) {:action=>"create", :controller=>"home"} new_home GET /home/new(.:format) {:action=>"new", :controller=>"home"} edit_home GET /home/:id/edit(.:format) {:action=>"edit", :controller=>"home"} home GET /home/:id(.:format) {:action=>"show", :controller=>"home"} PUT /home/:id(.:format) {:action=>"update", :controller=>"home"} DELETE /home/:id(.:format) {:action=>"destroy", :controller=>"home"} publicationinfo /documents/publicationinfo/:id(.:format) {:controller=>"documents", :action=>"publicationinfo"} publishinginfo /documents/update/publishinginfo/:id(.:format) {:controller=>"documents", :action=>"publishinginfo"} remove_image /documents/document_image_remove/:id(.:format) {:controller=>"documents", :action=>"remove_image"} make_primary_image /documents/make_primary_image/:id(.:format) {:controller=>"documents", :action=>"make_primary_image"} person_detail /person_detail/:id(.:format) {:controller=>"documents", :action=>"person_detail"} about /about(.:format) {:action=>"about", :controller=>"pages"} contact /contact(.:format) {:action=>"contact", :controller=>"pages"} privacy /privacy(.:format) {:action=>"privacy", :controller=>"pages"} terms /terms(.:format) {:action=>"terms", :controller=>"pages"} help /help(.:format) {:action=>"help", :controller=>"pages"} </code></pre>
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