How to rollback changes to HasMany in ember-data - ember.js

Question

I have following models:
App.Parent = DS.Model.extend({
foo: DS.attr('string'),
children: DS.hasMany('child', {async: true})
});
App.Child = DS.Model.extend({
bar: DS.attr('string')
});
I filled them with some fixture data:
App.ApplicationAdapter = DS.FixtureAdapter.extend();
App.Parent.FIXTURES = [
{
id:0,
foo: 'parent',
children: [0,1]
}
];
App.Child.FIXTURES = [
{
id: 0,
bar: 'child 0'
},
{
id: 1,
bar: 'child 1'
},
{
id: 2,
bar: 'child 2'
}
];
After I do some changes to the children relation, how can I rollback children relation to its latest saved state?
I push new child to manyArray in the following way:
this.store.find('child', 2).then(function(child){
model.get('children').pushObject(child);
})
This does change the relation (I see new child in my view), but parent record does not become dirty. Thus, when I try model.rollback() it does nothing. I also tried solution I found here How to rollback relationship changes in EmberData which is adding model.send('becomeDirty') before rollback, but it does not help.
Maybe I am adding children to my relation in a wrong way?
Thanks!

Answer 1

I used this to rollback related records that are dirty.
App.ParentRoute = Ember.Route.extend
model: ->
#get('store').createRecord('parent', child: #get('store').createRecord('child'))
actions:
willTransition: (transition) ->
rollbackRecords(#)
rollbackRecords = (context) ->
if context.get("controller.content.isDirty")
relationships = Ember.get(App[context.get('controller').resourceName], "relationshipsByName")
content = context.get('controller.content')
relationships.forEach (name, relationship) ->
relatedModel = content.get(name)
relatedModel.rollback() if relatedModel? and relatedModel.get('isDirty')
content.rollback()
true

Answer 2

Here is some code that will rollback a model, as well as it's relationships that I use:
var model = this.get('model');
var relatedModel, relatedModels;
model.constructor.eachRelationship(function (key, relationship) {
if (relationship.kind === 'hasMany') {
relatedModels = model.get(key);
if (relatedModels) {
relatedModels.invoke('rollback'); //since this is an array, need to call the rollback function differently
}
}
else {
relatedModel = model.get(key);
if (relatedModel) {
relatedModel.rollback();
}
}
});
model.rollback();
Hope this helps

Answer 3

I believe the other answers listed here only partially solve this problem. If you add a new related model or remove an existing one, rollback should reverse those as well and I believe the other answers don't address this. Here is a complete solution that provides proper dirty checking and a complete rollback for hasMany and belongsTo relationships:
https://stackoverflow.com/a/27184207/188740

Answer 4

I like to do the good ol' model.reload()
- it'll blow away all changes you haven't synced with your server though.