Rails: Undefined method 'to_sym'

Question

I'm getting the following error in my deployed Rails 2.3.5 application:

NoMethodError (undefined method `to_sym' for nil:NilClass):

My local testing install of the application, which uses Sqlite, doesn't get the error, but my deployed app running Mysql does. The only other difference between the two is I'm running Ruby 1.8.7 on my local machine and 1.8.6 on my deployment server.

I've included the code from User.rb and the error log below. I set this up following the Declarative Authorization and Embedded Authorization Railscasts.

---

EDIT: Here's the code for the application_controller, where I set current_user using before_filter:

class ApplicationController < ActionController::Base
  helper :all
  helper_method :current_user_session, :current_user 
  before_filter :set_current_user

  protected 

  def set_current_user
    Authorization.current_user = current_user
  end

  def current_user_session  
    return @current_user_session if defined?(@current_user_session)  
    @current_user_session = UserSession.find  
  end  

  def current_user  
    @current_user = current_user_session && current_user_session.record  
  end
end

--

User.rb:

class User < ActiveRecord::Base
  acts_as_authentic 

  has_many :products
  has_many :transactions

  ROLES = %w[admin dmstaff staff faculty]

  def role_symbols
    [role.to_sym]
  end  

end

The error log:

NoMethodError (undefined method `to_sym' for nil:NilClass):
  app/models/user.rb:10:in `role_symbols'
  /usr/lib/ruby/gems/1.8/gems/declarative_authorization 0.4/lib/declarative_authorization/authorization.rb:242:in `roles_for'
  /usr/lib/ruby/gems/1.8/gems/declarative_authorization-0.4/lib/declarative_authorization/authorization.rb:296:in  `user_roles_privleges_from_options'
  /usr/lib/ruby/gems/1.8/gems/declarative_authorization-0.4/lib/declarative_authorization/authorization.rb:161:in `permit!'
  /usr/lib/ruby/gems/1.8/gems/declarative_authorization-0.4/lib/declarative_authorization/in_controller.rb:580:in `permit!'
  /usr/lib/ruby/gems/1.8/gems/declarative_authorization-0.4/lib/declarative_authorization/in_controller.rb:109:in `filter_access_filter'
  /usr/lib/ruby/gems/1.8/gems/declarative_authorization-0.4/lib/declarative_authorization/in_controller.rb:109:in `each'
  /usr/lib/ruby/gems/1.8/gems/declarative_authorization-0.4/lib/declarative_authorization/in_controller.rb:109:in `all?'
  /usr/lib/ruby/gems/1.8/gems/declarative_authorization-0.4/lib/declarative_authorization/in_controller.rb:109:in `filter_access_filter'
  passenger (2.2.5) lib/phusion_passenger/rack/request_handler.rb:95:in `process_request'
  passenger (2.2.5) lib/phusion_passenger/abstract_request_handler.rb:207:in `main_loop'
  passenger (2.2.5) lib/phusion_passenger/railz/application_spawner.rb:378:in `start_request_handler'
  passenger (2.2.5) lib/phusion_passenger/railz/application_spawner.rb:336:in `handle_spawn_application'
  passenger (2.2.5) lib/phusion_passenger/utils.rb:183:in `safe_fork'
  passenger (2.2.5) lib/phusion_passenger/railz/application_spawner.rb:334:in `handle_spawn_application'
  passenger (2.2.5) lib/phusion_passenger/abstract_server.rb:352:in `__send__'
  passenger (2.2.5) lib/phusion_passenger/abstract_server.rb:352:in `main_loop'
  passenger (2.2.5) lib/phusion_passenger/abstract_server.rb:196:in `start_synchronously'
  passenger (2.2.5) lib/phusion_passenger/abstract_server.rb:163:in `start'
  passenger (2.2.5) lib/phusion_passenger/railz/application_spawner.rb:213:in `start'
  passenger (2.2.5) lib/phusion_passenger/spawn_manager.rb:262:in `spawn_rails_application'
  passenger (2.2.5) lib/phusion_passenger/abstract_server_collection.rb:126:in `lookup_or_add'
  passenger (2.2.5) lib/phusion_passenger/spawn_manager.rb:256:in `spawn_rails_application'
  passenger (2.2.5) lib/phusion_passenger/abstract_server_collection.rb:80:in `synchronize'
  passenger (2.2.5) lib/phusion_passenger/abstract_server_collection.rb:79:in `synchronize'
  passenger (2.2.5) lib/phusion_passenger/spawn_manager.rb:255:in `spawn_rails_application'
  passenger (2.2.5) lib/phusion_passenger/spawn_manager.rb:154:in `spawn_application'
  passenger (2.2.5) lib/phusion_passenger/spawn_manager.rb:287:in `handle_spawn_application'
  passenger (2.2.5) lib/phusion_passenger/abstract_server.rb:352:in `__send__'
  passenger (2.2.5) lib/phusion_passenger/abstract_server.rb:352:in `main_loop'
  passenger (2.2.5) lib/phusion_passenger/abstract_server.rb:196:in `start_synchronously'

Rendering /var/data/app/current/public/500.html (500 Internal Server Error)

Answer 1

  def role_symbols
    [role.to_sym]
  end

-> role is Nil. Do you define role somewhere?