No route matches with Nested Resources - ruby-on-rails

Question

I have two associated tables. Venues and Specials. A venue can have many specials. Once a user has created a venue I wish to allow them to create a special on the venues#index page. By using nested resources I have achieved the desired URL: /venues/5/specials/new.
However, my current code results with: No route matches {:controller=>"specials", :format=>nil}
I'm guessing the error is with my SpecialsController and the def new and def create functions.
I would like the URL to take me to a form page where I can enter new data for the specials
<%= link_to 'Add Special', new_venue_special_path(venue) %>
App1::Application.routes.draw do
resources :venues do
resources :specials
end
def new
#venue = Venue.find(params[:venue_id])
#special = #venue.specials.build
respond_to do |format|
format.html # new.html.erb
format.json { render json: #special }
end
end
def create
#venue = Venue.find(params[:venue_id])
#special = #venue.specials.build(params[:special])
respond_to do |format|
if #special.save
format.html { redirect_to #special, notice: 'Special was successfully created.' }
format.json { render json: #special, status: :created, location: #special }
else
format.html { render action: "new" }
format.json { render json: #special.errors, status: :unprocessable_entity }
end
end
end
Backtrace
Started GET "/venues/4/specials/new" for 127.0.0.1 at 2011-12-06 23:36:01 +0200
Processing by SpecialsController#new as HTML
Parameters: {"venue_id"=>"4"}
[1m[36mVenue Load (0.2ms)[0m [1mSELECT "venues".* FROM "venues" WHERE "venues"."id" = $1 LIMIT 1[0m [["id", "4"]]
Rendered specials/_form.html.erb (1.9ms)
Rendered specials/new.html.erb within layouts/application (2.6ms)
Completed 500 Internal Server Error in 97ms
ActionView::Template::Error (No route matches {:controller=>"specials", :format=>nil}):
1: <%= form_for(#special) do |f| %>
2: <% if #special.errors.any? %>
3: <div id="error_explanation">
4: <h2><%= pluralize(#special.errors.count, "error") %> prohibited this special from being saved:</h2>
app/views/specials/_form.html.erb:1:in `_app_views_specials__form_html_erb__2784079234875518470_70162904892440'
app/views/specials/new.html.erb:7:in `_app_views_specials_new_html_erb__115378566176177893_70162906293160'
app/controllers/specials_controller.rb:30:in `new'
Rendered /Users/andrewlynch/.rvm/gems/ruby-1.9.2-p290/gems/actionpack-3.1.3/lib/action_dispatch/middleware/templates/rescues/routing_error.erb within rescues/layout (0.7ms)

Answer 1

redirect_to #special
this will default to "specials_path", but you're using venue_special_path
you probably want:
redirect_to [#venue, #special]
and in the form you will need the same:
<%= form_for([#venue, #special]) do |f| %>
basically - the issue is that you have a nested resource... which means that every place where you are declaring a url path (including implicit places like form_for) has to be replaced with both the #venue and the #special, instead of just the #special.
you may come across this same "bug" elsewhere in your generated scaffold code... just do the same thing and you should be good.