Ember belongsTo relationship passing as nil to server on saving

Question

Ember CLI 0.2.5 + Rails 4.2 using ember-cli-rails gem, active_model_serializer (0.9.3)

I am currently trying to pass user into createRecord and it won't save or bind the user_id when passing to rails. Parameters come back as:

{"course"=>{"subject"=>"CSE", "number"=>110, "credit_hours"=>3, "grading_scale"=>"Regular", "user_id"=>nil}}

Ember Controller (Finding the user returns correct value)

import Ember from 'ember';

export default Ember.Controller.extend({
  scales: ['Regular', 'Plus/Minus', 'Plus', 'Minus'],
  weights: [],

  actions: {
    createCourse: function() {
      var self = this;
      var course = this.get('model');
      this.store.find('user', this.get('session.content.secure.id')).then(function(user) {
        course.set('user', user);
      })
      course.save().then(function(course){
        $.growl.notice({title: 'Course', message: 'Sucessfully created course.'})
      })
    }
  }
});

Rails Controller

    class CoursesController < ApplicationController

  def index
    @courses = User.find(params[:user_id]).courses
    render json: @courses
  end

  def show
    @course = Course.find(params[:id])
    render json: @course
  end

  def update
    @course = Course.find(params[:id])
    if @course.update_attributes(params[:course])
      render json: @course
    else
      render json: @course.errors, status: 500
    end
  end

  def create
    @course = Course.new(course_params)

    if @course.save
      render json: @course, status: :created
    else
      render json: @course.errors, status: 500
    end
  end

  private

  def course_params
    params.require(:course).permit(:subject, :number, :credit_hours, :grading_scale, :user_id)
  end

end

Serializer (I had a stack level too deep error here so i used user_id which i have seen done before, I even downgraded to 0.8.3 to fix that error and still no luck)

class CourseSerializer < ActiveModel::Serializer
  embed :ids, include: false

  attributes :id, :subject, :number, :credit_hours, :grading_scale, :user_id
  #has_one :user
  has_many :weights
  has_many :grades
end

Route (Pretty straight forward here)

import Ember from 'ember';
import AuthenticatedRouteMixin from 'simple-auth/mixins/authenticated-route-mixin';

export default Ember.Route.extend(AuthenticatedRouteMixin, {
  model: function() {
    var store = this.store;
    return store.createRecord('course');
  },
  setupController: function(controller, model) {
    controller.set('model', model);
  },
  actions: {
    willTransition: function() {
      var course = this.controller.get('model');
      course.rollback();
    }
  }
});

Snippet of Course Model

export default DS.Model.extend({
  user: DS.belongsTo('user'),
  weights: DS.hasMany('weight',{ async: true }),
  grades: DS.hasMany('grade',{ async: true }),
  subject: DS.attr('string'),
  number: DS.attr('number'),
  creditHours: DS.attr('number'),
  gradingScale: DS.attr('string')

Snippet of User Model

export default DS.Model.extend({
  courses: DS.hasMany('course'),
  grades: DS.hasMany('grade'),
  email: DS.attr('string'),
  name: DS.attr('string'),
  gradePoints: DS.attr('number'),
  gradeUnits: DS.attr('number'),
  password: DS.attr('string'),
  password_confirmation: DS.attr('string')

Let me know if i need to supply anything else. This has been frustrating me for awhile.

artych artych · Accepted Answer · 2015-06-11T16:25:37

In createCourse method course.save() runs before user promise becomes resolved, that's why you see user_id: nil. This would work:

createCourse: function() {
   var self = this;
   var course = this.get('model');
   this.store.find('user', this.get('session.content.secure.id')).then(function(user) {
      course.set('user', user);
      return course.save();
   }).then(function(course) {
       $.growl.notice({title: 'Course', message: 'Sucessfully created course.'});
   });
}

Ember belongsTo relationship passing as nil to server on saving

1 Answers