How to add a new many relationship to parent model?

Question

Disclaimer: I tried to make a jsfiddle of this, but without a public source for the RESTAdapter, I couldn't really make it work.

I have a model with a hasMany array of child models. I need to add a new model to this child array and save to the server:

App.FooModel = DS.Model.extend({
  'name': DS.attr('string'),
  'bars': DS.hasMany('App.BarModel')
});

App.BarModel = DS.Model.extend({
  'name': DS.attr('string'),
});

App.ApplicationController = Ember.Controller.extend({
  init: function() {
    var foo    = App.FooModel.find(101); // -- currently has bars[201, 202, 203]
    var newBar = loadFixture( App.BarModel, 204 );

    var self = this;
    setTimeout( function() { // -- just to be sure our models are loaded before we try this
      // foo.currentState: saved
      foo.get('bars').addObject(newBar);
      // foo.currentState: saved

      foo.store.commit(); // -- nothing happens
    }, 1000);
  }
});

App = Ember.Application.create({
  store: DS.Store.create({
    revision: 11
  })
});

But nothing happens. My parent model doesn't get marked as dirty, so the store never attempts a commit. Is there a different way I should be adding this relationship to the parent? Is this a bug?

Current Workaround:

foo.get('bars').addObject(newBar);

var save = foo.get('name');    
foo.set('name', (save + '!'));
foo.set('name', save); // -- this marks our record as dirty, so a save will actually happen

foo.store.commit();

Edit 1: I'm aware that ember-data will only serialize this data if it was embedded to begin with (https://stackoverflow.com/a/15145803/84762), but I have overridden my serializer to handle this. The issue I'm having is that the store never even attempts to save this change so we never even get to the serializer.

Edit 2: I suspect this might have something to do with this bug, but at the same that would mean this wouldn't work for anyone and I have a hard time believing no one else has run into this, yet.

score 1 · Accepted Answer · answered Mar 06 '13 at 14:52

1

It looks like you're Modeling a one to many relationship yet you didn't include the belongsTo option on App.BarModel. Check this link out:

http://emberjs.com/guides/models/defining-models/#toc_one-to-many

App.Post = DS.Model.extend({
    comments: DS.hasMany('App.Comment')
});

App.Comment = DS.Model.extend({
    post: DS.belongsTo('App.Post')
});

answered Mar 06 '13 at 14:52

commadelimited

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Adding a `belongsTo` on the child didn't work, but `hasMany` on the child, did. Seems odd that they didn't both work; maybe I was doing something wrong with the `belongsTo`. In any case, thank you -- adding the relationship to the child seems to be what did the trick. I seem to remember somewhere that having a hasMany/null relationship/inverse was supported now? If not, are there plans for it? In my particular case, the child `bar` objects are used *everywhere* in the app, and I really don't want to have 25 different relationships added to the child object in order to make the parent save. – KOGI Mar 06 '13 at 16:14
There is an inverse-null branch on Github. Perhaps they're working towards that? https://github.com/emberjs/data/tree/inverse-null – commadelimited Mar 06 '13 at 16:37
I also left a comment about the linked SO question in the OP. If you could check it out, that would be great! – KOGI Mar 06 '13 at 19:03

score 0 · Answer 2 · answered Mar 06 '13 at 10:02

For what I understand, you did not use the embedded feature of relationship but overrided your serializer to handle the serialization of bars objects into foo object.

I think your bug probably came from here : if your relation is not embedded there is no reason to mark the foo object dirty as when you add an object to his bars association what should change is usually a key foo_id of the bar object you added, then there is no changes of the foo object to send to the API.

How to add a new many relationship to parent model?

2 Answers2