Rails 3.1 limit the number of child models - ruby-on-rails

Question

Hello guys I've 2 models: User(aka parent) and Profil(aka child).And I want to limit the number of profil for a user to one.
models/user.rb
class User < ActiveRecord::Base
has_one :profil
end
models/profil.rb
class Profil < ActiveRecord::Base
attr_accessible :logo
belongs_to :user
mount_uploader :logo, ImageUploader
validate :limit_profil_to_one, :on => :create
def limit_profil_to_one
if self.user.profils(:reload).count > 1
errors.add(:base, "Exceeded thing limit")
end
end
end
But when I try to create a profil I get the following error message:
NoMethodError (undefined method `profils' for nil:NilClass):
app/models/profil.rb:11:in `limit_profil_to_one'
app/controllers/profils_controller.rb:52:in `block in create'
app/controllers/profils_controller.rb:51:in `create
controllers/profils_controller.rb
# -*- encoding : utf-8 -*-
class ProfilsController < ApplicationController
# GET /factures
# GET /factures.json
def index
#profils = Profil.all
respond_to do |format|
format.html # index.html.erb
format.json { render json: #profil }
end
end
# GET /profils/1
# GET /profils/1.json
def show
#profil = Profil.find(params[:id])
respond_to do |format|
format.html # show.html.erb
format.json { render json: #profil }
end
end
# GET /profils/new
# GET /profils/new.json
def new
#profil = Profil.new
respond_to do |format|
format.html # new.html.erb
format.json { render json: #profil }
end
end
# GET /profils/1/edit
def edit
#profil = Profil.find(params[:id])
end
# POST /profils
# POST /profils.json
def create
#profil = Profil.new(params[:profil])
respond_to do |format|
if #profil.save
format.html { redirect_to #profil, notice: 'Profil was successfully created.' }
format.json { render json: #profil, status: :created, location: #profil }
else
format.html { render action: "new" }
format.json { render json: #profil.errors, status: :unprocessable_entity }
end
end
end
# PUT /profils/1
# PUT /profils/1.json
def update
#profil = Profil.find(params[:id])
respond_to do |format|
if #profil.update_attributes(params[:profil])
format.html { redirect_to #profil, notice: 'Profil was successfully updated.' }
format.json { head :ok }
else
format.html { render action: "edit" }
format.json { render json: #profil.errors, status: :unprocessable_entity }
end
end
end
# DELETE /factures/1
# DELETE /factures/1.json
def destroy
#profil = Profil.find(params[:id])
#profil.destroy
respond_to do |format|
format.html { redirect_to profils_url }
format.json { head :ok }
end
end
end
What I am doing wrong?

Answer 1

Look at line 2 in the limit_profil_to_one - self.user is nil so it is failing.
def limit_profil_to_one
if self.user.profils(:reload).count > 1 # self.user is nil
errors.add(:base, "Exceeded thing limit")
end
end
I am making some assumptions about what your app is doing, but for this post I am going to assume that your controller has a current user defined in the controller and that you are creating a Profil for that User (side: note, what is a profil? I am assuming you actually mean profile) You should set the user in the controller to the user it is supposed to be, like so.
def create
#profil = Profil.new(params[:profil])
#profil.user = current_user # however you access the currently logged in user
respond_to do |format|
if #profil.save
format.html { redirect_to #profil, notice: 'Profil was successfully created.' }
format.json { render json: #profil, status: :created, location: #profil }
else
format.html { render action: "new" }
format.json { render json: #profil.errors, status: :unprocessable_entity }
end
end
end