heroku error - NoMethodError (undefined method `updated?' - ruby-on-rails

Question

I've a rails 3.1 app on Heroku, I keep getting an 500 error in production which I can't recreate in dev.
When I try to perform an update action in one of my controllers I get a 500. I get the following from heroku logs -
2011-12-05T13:52:35+00:00 app[web.1]: Completed 500 Internal Server Error in 15ms
2011-12-05T13:52:35+00:00 app[web.1]:
2011-12-05T13:52:35+00:00 app[web.1]: NoMethodError (undefined method `updated?' for #<ActiveRecord::Associations::HasOneAssociation:0x00000004058800>):
2011-12-05T13:52:35+00:00 app[web.1]: app/controllers/cars_controller.rb:81:in `block in update'
2011-12-05T13:52:35+00:00 app[web.1]: app/controllers/cars_controller.rb:80:in `update'
The update action on my cars controller is -
def update
#car = Car.find_by_url_identifier(params[:id])
respond_to do |format| #**line 80**
if #car.update_attributes(params[:car]) #**line 81**
CarMailer.gift_confirmation(#car).deliver
format.html { redirect_to(thanks_path(#car.url_identifier)) }
else
format.html { render action: "edit" }
end
end
end
The parameters being posted are -
{"utf8"=>"✓",
"_method"=>"put",
"authenticity_token"=>"RTXCVvdsKQHc8CxHLeYS9WuztcrI1b4H8SHsdfsKWu+Iz4=",
"car"=>{"name"=>"dgdfsdfsd",
"email"=>"test#test.com",
"recipient_attributes"=>{"name"=>"fdsfsd",
"address1"=>"sdfsdfdsf",
"address2"=>"dsfdsfsdf",
"city"=>"sdfdsf",
"postcode"=>"sdfds"},
"gift_id"=>"2",
"message"=>"fsdfsdfdsf",
"terms"=>"1"},
"commit"=>"submit",
"id"=>"test5"}
My car model looks like this -
class Car < ActiveRecord::Base
validates :name, :presence =>true, :on => :update
validates :url_identifier, :presence =>true, :on => :create
has_one :recipient
belongs_to :gift
accepts_nested_attributes_for :recipient
accepts_nested_attributes_for :gift
def to_param
self.url_identifier
end
end
Any idea how I can fix this? Apart from looking at herokus logs, how else can I debug this?
Oddly the app work for a while if I do a 'heroku restart'

Answer 1

I can't see anything wrong in the code. Since it works on your development machine, I am guessing it is something else. Some difference. Did you run your migrations on heroku?
After deploying on heroku, you have to run your migrations in a separate step. I am not sure if that would give this kind of error. Just guessing here.

Answer 2

I googled the error message. Have you had a look at this thread: http://ruby-forum.com/topic/81719 They had a similar problem and have posted their solution/hack. Might be worth a try.

Answer 3

It looks like you are trying to call the method update to an ActiveRecord::Associations object instead of (probably) the Car model, which is strange because you would think it would be fetched and called on the model if it isn't a method found in Arel.
You could try to debug this by using the production environment settings in your development environment by looking in config/enviroments/production.rb and using those settings for development.
You could also try and recreate the problem on heroku using heroku console