Ruby On Rails: CanCan with Devise error 'undefined method `find_by_name' for #<Role:0x304ad18>-Collection of common programming errors

I’m very confused of cancan, I tried to get roles for cancan out of my mysql database. I’m using a controller which got no actions like show/edit/destroy (it’s called a Non RESTful Controller I think?). I got a Role_id column in my user table and id and rolename in my roles table.

All I get is this error:

undefined method `find_by_name’ for #

Ability.rb:
 class Ability
      include CanCan::Ability
      def initialize(user)
        can :manage, :all if user.role? :admin
    end
    end

And here is my User.rb:

User.rb:
class User < ActiveRecord::Base
  # Include default devise modules. Others available are:
  # :token_authenticatable,
  # :lockable, :timeoutable and :omniauthable
  devise :database_authenticatable, :registerable, :confirmable,
         :recoverable, :rememberable, :trackable, :validatable

  # Setup accessible (or protected) attributes for your model
  attr_accessible :email, :password, :password_confirmation, :remember_me, :username, :firstname, :lastname, :birthday
  # attr_accessible :title, :body

  validates_uniqueness_of :username
  belongs_to :role

def role?(role)
    return !!self.role.find_by_name(role.to_s.camelize)
end
end

Role.rb:

class Role < ActiveRecord::Base
  has_many :users
  attr_accessible :users, :name 
end

And here the controller I’m working in:

class WsdlController < ApplicationController
 authorize_resource :class => false
    $liga_id = 456
    $liga_short = "bl1"
    $saison = 2012

    def connect
        @client = Savon::Client.new("http://www.openligadb.de/Webservices/Sportsdata.asmx?WSDL")
        @output = ""
    end

    def get_all_for_new_saison
        if @client.nil?
            connect
        end
        #get_teams_by_league_saison
        #get_matchdata_by_league_saison
    end 
end

1. find_by_name is an ActiveRecord class method. (See the Active Record Query Interface Guide) You are invoking it like an instance method.

   Try changing this:

   def role?(role)
       return !!self.role.find_by_name(role.to_s.camelize)
   end
   

   to something like this:

   def role?(role_name)
       return self.role.present? && self.role.name == role_name.to_s
   end
   

   Of course, in ruby, both return and self are optional.

Originally posted 2013-11-09 22:47:57.