# Best practice for Ember data adding ids to embedded records?

**URL:** <https://discuss.emberjs.com/t/best-practice-for-ember-data-adding-ids-to-embedded-records/7712>\
**Category:** Ember Data\
**Created:** [April 4, 2015, 7:34am UTC](https://discuss.emberjs.com/t/best-practice-for-ember-data-adding-ids-to-embedded-records/7712 "2015-04-04T07:34:57Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![bengarnett](https://avatars.discourse-cdn.com/v4/letter/b/2acd7d/32.png) [@bengarnett](https://discuss.emberjs.com/u/bengarnett)\
**Post date:** [April 4, 2015, 7:34am UTC](https://discuss.emberjs.com/t/best-practice-for-ember-data-adding-ids-to-embedded-records/7712/1 "2015-04-04T07:34:57Z")

</div>

I have data from the server that looks like this:

```
var items = [
    { id: 1, details: [{a:1},{b:2},{c:3}] },
    { id: 2, details: [{x:1},{y:2}] }
];

```

and a data model

```
//models/item.js
export default DS.Model.extend({
 details: DS.hasMany('detail'), ...
});
//models/detail.js
export default DS.Model.extend({
 details: DS.belongsTo('item'), ...
});

```

The items have id’s but the details do not resulting in

> Error while processing route: items.index Assertion Failed: You must include an `id` for app@model:detail: in an object passed to `push`

I solved this by adding ids in the serializer in a loop

import DS from ‘ember-data’;

```
export default DS.RESTSerializer.extend(DS.EmbeddedRecordsMixin,{
  attrs: {
    items: { serialize: 'ids', deserialize: 'records'}
  },
  extractArray: function(store, type, payload, id, requestType) {
     var idx = 1;
     payload.items.forEach(function(item) {
       item.details.forEach(function(detail) {
         detail.id = idx++;
       })
     })
   return this._super.apply(this, arguments);
}
});

```

**Is there a better way?**